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Linux 2.6.31.8
[linux/fpc-iii.git] / arch / ia64 / kernel / perfmon.c
blobf1782705b1f72caaf2cae0ae96ab869b84a8e0f3
1 /*
2 * This file implements the perfmon-2 subsystem which is used
3 * to program the IA-64 Performance Monitoring Unit (PMU).
4 *
5 * The initial version of perfmon.c was written by
6 * Ganesh Venkitachalam, IBM Corp.
7 *
8 * Then it was modified for perfmon-1.x by Stephane Eranian and
9 * David Mosberger, Hewlett Packard Co.
10 *
11 * Version Perfmon-2.x is a rewrite of perfmon-1.x
12 * by Stephane Eranian, Hewlett Packard Co.
13 *
14 * Copyright (C) 1999-2005 Hewlett Packard Co
15 * Stephane Eranian <eranian@hpl.hp.com>
16 * David Mosberger-Tang <davidm@hpl.hp.com>
17 *
18 * More information about perfmon available at:
19 * http://www.hpl.hp.com/research/linux/perfmon
20 */
21
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/interrupt.h>
26 #include <linux/proc_fs.h>
27 #include <linux/seq_file.h>
28 #include <linux/init.h>
29 #include <linux/vmalloc.h>
30 #include <linux/mm.h>
31 #include <linux/sysctl.h>
32 #include <linux/list.h>
33 #include <linux/file.h>
34 #include <linux/poll.h>
35 #include <linux/vfs.h>
36 #include <linux/smp.h>
37 #include <linux/pagemap.h>
38 #include <linux/mount.h>
39 #include <linux/bitops.h>
40 #include <linux/capability.h>
41 #include <linux/rcupdate.h>
42 #include <linux/completion.h>
43 #include <linux/tracehook.h>
44
45 #include <asm/errno.h>
46 #include <asm/intrinsics.h>
47 #include <asm/page.h>
48 #include <asm/perfmon.h>
49 #include <asm/processor.h>
50 #include <asm/signal.h>
51 #include <asm/system.h>
52 #include <asm/uaccess.h>
53 #include <asm/delay.h>
54
55 #ifdef CONFIG_PERFMON
56 /*
57 * perfmon context state
58 */
59 #define PFM_CTX_UNLOADED 1 /* context is not loaded onto any task */
60 #define PFM_CTX_LOADED 2 /* context is loaded onto a task */
61 #define PFM_CTX_MASKED 3 /* context is loaded but monitoring is masked due to overflow */
62 #define PFM_CTX_ZOMBIE 4 /* owner of the context is closing it */
63
64 #define PFM_INVALID_ACTIVATION (~0UL)
65
66 #define PFM_NUM_PMC_REGS 64 /* PMC save area for ctxsw */
67 #define PFM_NUM_PMD_REGS 64 /* PMD save area for ctxsw */
68
69 /*
70 * depth of message queue
71 */
72 #define PFM_MAX_MSGS 32
73 #define PFM_CTXQ_EMPTY(g) ((g)->ctx_msgq_head == (g)->ctx_msgq_tail)
74
75 /*
76 * type of a PMU register (bitmask).
77 * bitmask structure:
78 * bit0 : register implemented
79 * bit1 : end marker
80 * bit2-3 : reserved
81 * bit4 : pmc has pmc.pm
82 * bit5 : pmc controls a counter (has pmc.oi), pmd is used as counter
83 * bit6-7 : register type
84 * bit8-31: reserved
85 */
86 #define PFM_REG_NOTIMPL 0x0 /* not implemented at all */
87 #define PFM_REG_IMPL 0x1 /* register implemented */
88 #define PFM_REG_END 0x2 /* end marker */
89 #define PFM_REG_MONITOR (0x1<<4|PFM_REG_IMPL) /* a PMC with a pmc.pm field only */
90 #define PFM_REG_COUNTING (0x2<<4|PFM_REG_MONITOR) /* a monitor + pmc.oi+ PMD used as a counter */
91 #define PFM_REG_CONTROL (0x4<<4|PFM_REG_IMPL) /* PMU control register */
92 #define PFM_REG_CONFIG (0x8<<4|PFM_REG_IMPL) /* configuration register */
93 #define PFM_REG_BUFFER (0xc<<4|PFM_REG_IMPL) /* PMD used as buffer */
94
95 #define PMC_IS_LAST(i) (pmu_conf->pmc_desc[i].type & PFM_REG_END)
96 #define PMD_IS_LAST(i) (pmu_conf->pmd_desc[i].type & PFM_REG_END)
97
98 #define PMC_OVFL_NOTIFY(ctx, i) ((ctx)->ctx_pmds[i].flags & PFM_REGFL_OVFL_NOTIFY)
99
100 /* i assumed unsigned */
101 #define PMC_IS_IMPL(i) (i< PMU_MAX_PMCS && (pmu_conf->pmc_desc[i].type & PFM_REG_IMPL))
102 #define PMD_IS_IMPL(i) (i< PMU_MAX_PMDS && (pmu_conf->pmd_desc[i].type & PFM_REG_IMPL))
103
104 /* XXX: these assume that register i is implemented */
105 #define PMD_IS_COUNTING(i) ((pmu_conf->pmd_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING)
106 #define PMC_IS_COUNTING(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING)
107 #define PMC_IS_MONITOR(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_MONITOR) == PFM_REG_MONITOR)
108 #define PMC_IS_CONTROL(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_CONTROL) == PFM_REG_CONTROL)
109
110 #define PMC_DFL_VAL(i) pmu_conf->pmc_desc[i].default_value
111 #define PMC_RSVD_MASK(i) pmu_conf->pmc_desc[i].reserved_mask
112 #define PMD_PMD_DEP(i) pmu_conf->pmd_desc[i].dep_pmd[0]
113 #define PMC_PMD_DEP(i) pmu_conf->pmc_desc[i].dep_pmd[0]
114
115 #define PFM_NUM_IBRS IA64_NUM_DBG_REGS
116 #define PFM_NUM_DBRS IA64_NUM_DBG_REGS
117
118 #define CTX_OVFL_NOBLOCK(c) ((c)->ctx_fl_block == 0)
119 #define CTX_HAS_SMPL(c) ((c)->ctx_fl_is_sampling)
120 #define PFM_CTX_TASK(h) (h)->ctx_task
121
122 #define PMU_PMC_OI 5 /* position of pmc.oi bit */
123
124 /* XXX: does not support more than 64 PMDs */
125 #define CTX_USED_PMD(ctx, mask) (ctx)->ctx_used_pmds[0] |= (mask)
126 #define CTX_IS_USED_PMD(ctx, c) (((ctx)->ctx_used_pmds[0] & (1UL << (c))) != 0UL)
127
128 #define CTX_USED_MONITOR(ctx, mask) (ctx)->ctx_used_monitors[0] |= (mask)
129
130 #define CTX_USED_IBR(ctx,n) (ctx)->ctx_used_ibrs[(n)>>6] |= 1UL<< ((n) % 64)
131 #define CTX_USED_DBR(ctx,n) (ctx)->ctx_used_dbrs[(n)>>6] |= 1UL<< ((n) % 64)
132 #define CTX_USES_DBREGS(ctx) (((pfm_context_t *)(ctx))->ctx_fl_using_dbreg==1)
133 #define PFM_CODE_RR 0 /* requesting code range restriction */
134 #define PFM_DATA_RR 1 /* requestion data range restriction */
135
136 #define PFM_CPUINFO_CLEAR(v) pfm_get_cpu_var(pfm_syst_info) &= ~(v)
137 #define PFM_CPUINFO_SET(v) pfm_get_cpu_var(pfm_syst_info) |= (v)
138 #define PFM_CPUINFO_GET() pfm_get_cpu_var(pfm_syst_info)
139
140 #define RDEP(x) (1UL<<(x))
141
142 /*
143 * context protection macros
144 * in SMP:
145 * - we need to protect against CPU concurrency (spin_lock)
146 * - we need to protect against PMU overflow interrupts (local_irq_disable)
147 * in UP:
148 * - we need to protect against PMU overflow interrupts (local_irq_disable)
149 *
150 * spin_lock_irqsave()/spin_unlock_irqrestore():
151 * in SMP: local_irq_disable + spin_lock
152 * in UP : local_irq_disable
153 *
154 * spin_lock()/spin_lock():
155 * in UP : removed automatically
156 * in SMP: protect against context accesses from other CPU. interrupts
157 * are not masked. This is useful for the PMU interrupt handler
158 * because we know we will not get PMU concurrency in that code.
159 */
160 #define PROTECT_CTX(c, f) \
161 do { \
162 DPRINT(("spinlock_irq_save ctx %p by [%d]\n", c, task_pid_nr(current))); \
163 spin_lock_irqsave(&(c)->ctx_lock, f); \
164 DPRINT(("spinlocked ctx %p by [%d]\n", c, task_pid_nr(current))); \
165 } while(0)
166
167 #define UNPROTECT_CTX(c, f) \
168 do { \
169 DPRINT(("spinlock_irq_restore ctx %p by [%d]\n", c, task_pid_nr(current))); \
170 spin_unlock_irqrestore(&(c)->ctx_lock, f); \
171 } while(0)
172
173 #define PROTECT_CTX_NOPRINT(c, f) \
174 do { \
175 spin_lock_irqsave(&(c)->ctx_lock, f); \
176 } while(0)
177
178
179 #define UNPROTECT_CTX_NOPRINT(c, f) \
180 do { \
181 spin_unlock_irqrestore(&(c)->ctx_lock, f); \
182 } while(0)
183
184
185 #define PROTECT_CTX_NOIRQ(c) \
186 do { \
187 spin_lock(&(c)->ctx_lock); \
188 } while(0)
189
190 #define UNPROTECT_CTX_NOIRQ(c) \
191 do { \
192 spin_unlock(&(c)->ctx_lock); \
193 } while(0)
194
195
196 #ifdef CONFIG_SMP
197
198 #define GET_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)
199 #define INC_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)++
200 #define SET_ACTIVATION(c) (c)->ctx_last_activation = GET_ACTIVATION()
201
202 #else /* !CONFIG_SMP */
203 #define SET_ACTIVATION(t) do {} while(0)
204 #define GET_ACTIVATION(t) do {} while(0)
205 #define INC_ACTIVATION(t) do {} while(0)
206 #endif /* CONFIG_SMP */
207
208 #define SET_PMU_OWNER(t, c) do { pfm_get_cpu_var(pmu_owner) = (t); pfm_get_cpu_var(pmu_ctx) = (c); } while(0)
209 #define GET_PMU_OWNER() pfm_get_cpu_var(pmu_owner)
210 #define GET_PMU_CTX() pfm_get_cpu_var(pmu_ctx)
211
212 #define LOCK_PFS(g) spin_lock_irqsave(&pfm_sessions.pfs_lock, g)
213 #define UNLOCK_PFS(g) spin_unlock_irqrestore(&pfm_sessions.pfs_lock, g)
214
215 #define PFM_REG_RETFLAG_SET(flags, val) do { flags &= ~PFM_REG_RETFL_MASK; flags |= (val); } while(0)
216
217 /*
218 * cmp0 must be the value of pmc0
219 */
220 #define PMC0_HAS_OVFL(cmp0) (cmp0 & ~0x1UL)
221
222 #define PFMFS_MAGIC 0xa0b4d889
223
224 /*
225 * debugging
226 */
227 #define PFM_DEBUGGING 1
228 #ifdef PFM_DEBUGGING
229 #define DPRINT(a) \
230 do { \
231 if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d [%d] ", __func__, __LINE__, smp_processor_id(), task_pid_nr(current)); printk a; } \
232 } while (0)
233
234 #define DPRINT_ovfl(a) \
235 do { \
236 if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d [%d] ", __func__, __LINE__, smp_processor_id(), task_pid_nr(current)); printk a; } \
237 } while (0)
238 #endif
239
240 /*
241 * 64-bit software counter structure
242 *
243 * the next_reset_type is applied to the next call to pfm_reset_regs()
244 */
245 typedef struct {
246 unsigned long val; /* virtual 64bit counter value */
247 unsigned long lval; /* last reset value */
248 unsigned long long_reset; /* reset value on sampling overflow */
249 unsigned long short_reset; /* reset value on overflow */
250 unsigned long reset_pmds[4]; /* which other pmds to reset when this counter overflows */
251 unsigned long smpl_pmds[4]; /* which pmds are accessed when counter overflow */
252 unsigned long seed; /* seed for random-number generator */
253 unsigned long mask; /* mask for random-number generator */
254 unsigned int flags; /* notify/do not notify */
255 unsigned long eventid; /* overflow event identifier */
256 } pfm_counter_t;
257
258 /*
259 * context flags
260 */
261 typedef struct {
262 unsigned int block:1; /* when 1, task will blocked on user notifications */
263 unsigned int system:1; /* do system wide monitoring */
264 unsigned int using_dbreg:1; /* using range restrictions (debug registers) */
265 unsigned int is_sampling:1; /* true if using a custom format */
266 unsigned int excl_idle:1; /* exclude idle task in system wide session */
267 unsigned int going_zombie:1; /* context is zombie (MASKED+blocking) */
268 unsigned int trap_reason:2; /* reason for going into pfm_handle_work() */
269 unsigned int no_msg:1; /* no message sent on overflow */
270 unsigned int can_restart:1; /* allowed to issue a PFM_RESTART */
271 unsigned int reserved:22;
272 } pfm_context_flags_t;
273
274 #define PFM_TRAP_REASON_NONE 0x0 /* default value */
275 #define PFM_TRAP_REASON_BLOCK 0x1 /* we need to block on overflow */
276 #define PFM_TRAP_REASON_RESET 0x2 /* we need to reset PMDs */
277
278
279 /*
280 * perfmon context: encapsulates all the state of a monitoring session
281 */
282
283 typedef struct pfm_context {
284 spinlock_t ctx_lock; /* context protection */
285
286 pfm_context_flags_t ctx_flags; /* bitmask of flags (block reason incl.) */
287 unsigned int ctx_state; /* state: active/inactive (no bitfield) */
288
289 struct task_struct *ctx_task; /* task to which context is attached */
290
291 unsigned long ctx_ovfl_regs[4]; /* which registers overflowed (notification) */
292
293 struct completion ctx_restart_done; /* use for blocking notification mode */
294
295 unsigned long ctx_used_pmds[4]; /* bitmask of PMD used */
296 unsigned long ctx_all_pmds[4]; /* bitmask of all accessible PMDs */
297 unsigned long ctx_reload_pmds[4]; /* bitmask of force reload PMD on ctxsw in */
298
299 unsigned long ctx_all_pmcs[4]; /* bitmask of all accessible PMCs */
300 unsigned long ctx_reload_pmcs[4]; /* bitmask of force reload PMC on ctxsw in */
301 unsigned long ctx_used_monitors[4]; /* bitmask of monitor PMC being used */
302
303 unsigned long ctx_pmcs[PFM_NUM_PMC_REGS]; /* saved copies of PMC values */
304
305 unsigned int ctx_used_ibrs[1]; /* bitmask of used IBR (speedup ctxsw in) */
306 unsigned int ctx_used_dbrs[1]; /* bitmask of used DBR (speedup ctxsw in) */
307 unsigned long ctx_dbrs[IA64_NUM_DBG_REGS]; /* DBR values (cache) when not loaded */
308 unsigned long ctx_ibrs[IA64_NUM_DBG_REGS]; /* IBR values (cache) when not loaded */
309
310 pfm_counter_t ctx_pmds[PFM_NUM_PMD_REGS]; /* software state for PMDS */
311
312 unsigned long th_pmcs[PFM_NUM_PMC_REGS]; /* PMC thread save state */
313 unsigned long th_pmds[PFM_NUM_PMD_REGS]; /* PMD thread save state */
314
315 unsigned long ctx_saved_psr_up; /* only contains psr.up value */
316
317 unsigned long ctx_last_activation; /* context last activation number for last_cpu */
318 unsigned int ctx_last_cpu; /* CPU id of current or last CPU used (SMP only) */
319 unsigned int ctx_cpu; /* cpu to which perfmon is applied (system wide) */
320
321 int ctx_fd; /* file descriptor used my this context */
322 pfm_ovfl_arg_t ctx_ovfl_arg; /* argument to custom buffer format handler */
323
324 pfm_buffer_fmt_t *ctx_buf_fmt; /* buffer format callbacks */
325 void *ctx_smpl_hdr; /* points to sampling buffer header kernel vaddr */
326 unsigned long ctx_smpl_size; /* size of sampling buffer */
327 void *ctx_smpl_vaddr; /* user level virtual address of smpl buffer */
328
329 wait_queue_head_t ctx_msgq_wait;
330 pfm_msg_t ctx_msgq[PFM_MAX_MSGS];
331 int ctx_msgq_head;
332 int ctx_msgq_tail;
333 struct fasync_struct *ctx_async_queue;
334
335 wait_queue_head_t ctx_zombieq; /* termination cleanup wait queue */
336 } pfm_context_t;
337
338 /*
339 * magic number used to verify that structure is really
340 * a perfmon context
341 */
342 #define PFM_IS_FILE(f) ((f)->f_op == &pfm_file_ops)
343
344 #define PFM_GET_CTX(t) ((pfm_context_t *)(t)->thread.pfm_context)
345
346 #ifdef CONFIG_SMP
347 #define SET_LAST_CPU(ctx, v) (ctx)->ctx_last_cpu = (v)
348 #define GET_LAST_CPU(ctx) (ctx)->ctx_last_cpu
349 #else
350 #define SET_LAST_CPU(ctx, v) do {} while(0)
351 #define GET_LAST_CPU(ctx) do {} while(0)
352 #endif
353
354
355 #define ctx_fl_block ctx_flags.block
356 #define ctx_fl_system ctx_flags.system
357 #define ctx_fl_using_dbreg ctx_flags.using_dbreg
358 #define ctx_fl_is_sampling ctx_flags.is_sampling
359 #define ctx_fl_excl_idle ctx_flags.excl_idle
360 #define ctx_fl_going_zombie ctx_flags.going_zombie
361 #define ctx_fl_trap_reason ctx_flags.trap_reason
362 #define ctx_fl_no_msg ctx_flags.no_msg
363 #define ctx_fl_can_restart ctx_flags.can_restart
364
365 #define PFM_SET_WORK_PENDING(t, v) do { (t)->thread.pfm_needs_checking = v; } while(0);
366 #define PFM_GET_WORK_PENDING(t) (t)->thread.pfm_needs_checking
367
368 /*
369 * global information about all sessions
370 * mostly used to synchronize between system wide and per-process
371 */
372 typedef struct {
373 spinlock_t pfs_lock; /* lock the structure */
374
375 unsigned int pfs_task_sessions; /* number of per task sessions */
376 unsigned int pfs_sys_sessions; /* number of per system wide sessions */
377 unsigned int pfs_sys_use_dbregs; /* incremented when a system wide session uses debug regs */
378 unsigned int pfs_ptrace_use_dbregs; /* incremented when a process uses debug regs */
379 struct task_struct *pfs_sys_session[NR_CPUS]; /* point to task owning a system-wide session */
380 } pfm_session_t;
381
382 /*
383 * information about a PMC or PMD.
384 * dep_pmd[]: a bitmask of dependent PMD registers
385 * dep_pmc[]: a bitmask of dependent PMC registers
386 */
387 typedef int (*pfm_reg_check_t)(struct task_struct *task, pfm_context_t *ctx, unsigned int cnum, unsigned long *val, struct pt_regs *regs);
388 typedef struct {
389 unsigned int type;
390 int pm_pos;
391 unsigned long default_value; /* power-on default value */
392 unsigned long reserved_mask; /* bitmask of reserved bits */
393 pfm_reg_check_t read_check;
394 pfm_reg_check_t write_check;
395 unsigned long dep_pmd[4];
396 unsigned long dep_pmc[4];
397 } pfm_reg_desc_t;
398
399 /* assume cnum is a valid monitor */
400 #define PMC_PM(cnum, val) (((val) >> (pmu_conf->pmc_desc[cnum].pm_pos)) & 0x1)
401
402 /*
403 * This structure is initialized at boot time and contains
404 * a description of the PMU main characteristics.
405 *
406 * If the probe function is defined, detection is based
407 * on its return value:
408 * - 0 means recognized PMU
409 * - anything else means not supported
410 * When the probe function is not defined, then the pmu_family field
411 * is used and it must match the host CPU family such that:
412 * - cpu->family & config->pmu_family != 0
413 */
414 typedef struct {
415 unsigned long ovfl_val; /* overflow value for counters */
416
417 pfm_reg_desc_t *pmc_desc; /* detailed PMC register dependencies descriptions */
418 pfm_reg_desc_t *pmd_desc; /* detailed PMD register dependencies descriptions */
419
420 unsigned int num_pmcs; /* number of PMCS: computed at init time */
421 unsigned int num_pmds; /* number of PMDS: computed at init time */
422 unsigned long impl_pmcs[4]; /* bitmask of implemented PMCS */
423 unsigned long impl_pmds[4]; /* bitmask of implemented PMDS */
424
425 char *pmu_name; /* PMU family name */
426 unsigned int pmu_family; /* cpuid family pattern used to identify pmu */
427 unsigned int flags; /* pmu specific flags */
428 unsigned int num_ibrs; /* number of IBRS: computed at init time */
429 unsigned int num_dbrs; /* number of DBRS: computed at init time */
430 unsigned int num_counters; /* PMC/PMD counting pairs : computed at init time */
431 int (*probe)(void); /* customized probe routine */
432 unsigned int use_rr_dbregs:1; /* set if debug registers used for range restriction */
433 } pmu_config_t;
434 /*
435 * PMU specific flags
436 */
437 #define PFM_PMU_IRQ_RESEND 1 /* PMU needs explicit IRQ resend */
438
439 /*
440 * debug register related type definitions
441 */
442 typedef struct {
443 unsigned long ibr_mask:56;
444 unsigned long ibr_plm:4;
445 unsigned long ibr_ig:3;
446 unsigned long ibr_x:1;
447 } ibr_mask_reg_t;
448
449 typedef struct {
450 unsigned long dbr_mask:56;
451 unsigned long dbr_plm:4;
452 unsigned long dbr_ig:2;
453 unsigned long dbr_w:1;
454 unsigned long dbr_r:1;
455 } dbr_mask_reg_t;
456
457 typedef union {
458 unsigned long val;
459 ibr_mask_reg_t ibr;
460 dbr_mask_reg_t dbr;
461 } dbreg_t;
462
463
464 /*
465 * perfmon command descriptions
466 */
467 typedef struct {
468 int (*cmd_func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
469 char *cmd_name;
470 int cmd_flags;
471 unsigned int cmd_narg;
472 size_t cmd_argsize;
473 int (*cmd_getsize)(void *arg, size_t *sz);
474 } pfm_cmd_desc_t;
475
476 #define PFM_CMD_FD 0x01 /* command requires a file descriptor */
477 #define PFM_CMD_ARG_READ 0x02 /* command must read argument(s) */
478 #define PFM_CMD_ARG_RW 0x04 /* command must read/write argument(s) */
479 #define PFM_CMD_STOP 0x08 /* command does not work on zombie context */
480
481
482 #define PFM_CMD_NAME(cmd) pfm_cmd_tab[(cmd)].cmd_name
483 #define PFM_CMD_READ_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_READ)
484 #define PFM_CMD_RW_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_RW)
485 #define PFM_CMD_USE_FD(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_FD)
486 #define PFM_CMD_STOPPED(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_STOP)
487
488 #define PFM_CMD_ARG_MANY -1 /* cannot be zero */
489
490 typedef struct {
491 unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */
492 unsigned long pfm_replay_ovfl_intr_count; /* keep track of replayed ovfl interrupts */
493 unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */
494 unsigned long pfm_ovfl_intr_cycles; /* cycles spent processing ovfl interrupts */
495 unsigned long pfm_ovfl_intr_cycles_min; /* min cycles spent processing ovfl interrupts */
496 unsigned long pfm_ovfl_intr_cycles_max; /* max cycles spent processing ovfl interrupts */
497 unsigned long pfm_smpl_handler_calls;
498 unsigned long pfm_smpl_handler_cycles;
499 char pad[SMP_CACHE_BYTES] ____cacheline_aligned;
500 } pfm_stats_t;
501
502 /*
503 * perfmon internal variables
504 */
505 static pfm_stats_t pfm_stats[NR_CPUS];
506 static pfm_session_t pfm_sessions; /* global sessions information */
507
508 static DEFINE_SPINLOCK(pfm_alt_install_check);
509 static pfm_intr_handler_desc_t *pfm_alt_intr_handler;
510
511 static struct proc_dir_entry *perfmon_dir;
512 static pfm_uuid_t pfm_null_uuid = {0,};
513
514 static spinlock_t pfm_buffer_fmt_lock;
515 static LIST_HEAD(pfm_buffer_fmt_list);
516
517 static pmu_config_t *pmu_conf;
518
519 /* sysctl() controls */
520 pfm_sysctl_t pfm_sysctl;
521 EXPORT_SYMBOL(pfm_sysctl);
522
523 static ctl_table pfm_ctl_table[]={
524 {
525 .ctl_name = CTL_UNNUMBERED,
526 .procname = "debug",
527 .data = &pfm_sysctl.debug,
528 .maxlen = sizeof(int),
529 .mode = 0666,
530 .proc_handler = &proc_dointvec,
531 },
532 {
533 .ctl_name = CTL_UNNUMBERED,
534 .procname = "debug_ovfl",
535 .data = &pfm_sysctl.debug_ovfl,
536 .maxlen = sizeof(int),
537 .mode = 0666,
538 .proc_handler = &proc_dointvec,
539 },
540 {
541 .ctl_name = CTL_UNNUMBERED,
542 .procname = "fastctxsw",
543 .data = &pfm_sysctl.fastctxsw,
544 .maxlen = sizeof(int),
545 .mode = 0600,
546 .proc_handler = &proc_dointvec,
547 },
548 {
549 .ctl_name = CTL_UNNUMBERED,
550 .procname = "expert_mode",
551 .data = &pfm_sysctl.expert_mode,
552 .maxlen = sizeof(int),
553 .mode = 0600,
554 .proc_handler = &proc_dointvec,
555 },
556 {}
557 };
558 static ctl_table pfm_sysctl_dir[] = {
559 {
560 .ctl_name = CTL_UNNUMBERED,
561 .procname = "perfmon",
562 .mode = 0555,
563 .child = pfm_ctl_table,
564 },
565 {}
566 };
567 static ctl_table pfm_sysctl_root[] = {
568 {
569 .ctl_name = CTL_KERN,
570 .procname = "kernel",
571 .mode = 0555,
572 .child = pfm_sysctl_dir,
573 },
574 {}
575 };
576 static struct ctl_table_header *pfm_sysctl_header;
577
578 static int pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
579
580 #define pfm_get_cpu_var(v) __ia64_per_cpu_var(v)
581 #define pfm_get_cpu_data(a,b) per_cpu(a, b)
582
583 static inline void
584 pfm_put_task(struct task_struct *task)
585 {
586 if (task != current) put_task_struct(task);
587 }
588
589 static inline void
590 pfm_reserve_page(unsigned long a)
591 {
592 SetPageReserved(vmalloc_to_page((void *)a));
593 }
594 static inline void
595 pfm_unreserve_page(unsigned long a)
596 {
597 ClearPageReserved(vmalloc_to_page((void*)a));
598 }
599
600 static inline unsigned long
601 pfm_protect_ctx_ctxsw(pfm_context_t *x)
602 {
603 spin_lock(&(x)->ctx_lock);
604 return 0UL;
605 }
606
607 static inline void
608 pfm_unprotect_ctx_ctxsw(pfm_context_t *x, unsigned long f)
609 {
610 spin_unlock(&(x)->ctx_lock);
611 }
612
613 static inline unsigned int
614 pfm_do_munmap(struct mm_struct *mm, unsigned long addr, size_t len, int acct)
615 {
616 return do_munmap(mm, addr, len);
617 }
618
619 static inline unsigned long
620 pfm_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, unsigned long exec)
621 {
622 return get_unmapped_area(file, addr, len, pgoff, flags);
623 }
624
625
626 static int
627 pfmfs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data,
628 struct vfsmount *mnt)
629 {
630 return get_sb_pseudo(fs_type, "pfm:", NULL, PFMFS_MAGIC, mnt);
631 }
632
633 static struct file_system_type pfm_fs_type = {
634 .name = "pfmfs",
635 .get_sb = pfmfs_get_sb,
636 .kill_sb = kill_anon_super,
637 };
638
639 DEFINE_PER_CPU(unsigned long, pfm_syst_info);
640 DEFINE_PER_CPU(struct task_struct *, pmu_owner);
641 DEFINE_PER_CPU(pfm_context_t *, pmu_ctx);
642 DEFINE_PER_CPU(unsigned long, pmu_activation_number);
643 EXPORT_PER_CPU_SYMBOL_GPL(pfm_syst_info);
644
645
646 /* forward declaration */
647 static const struct file_operations pfm_file_ops;
648
649 /*
650 * forward declarations
651 */
652 #ifndef CONFIG_SMP
653 static void pfm_lazy_save_regs (struct task_struct *ta);
654 #endif
655
656 void dump_pmu_state(const char *);
657 static int pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
658
659 #include "perfmon_itanium.h"
660 #include "perfmon_mckinley.h"
661 #include "perfmon_montecito.h"
662 #include "perfmon_generic.h"
663
664 static pmu_config_t *pmu_confs[]={
665 &pmu_conf_mont,
666 &pmu_conf_mck,
667 &pmu_conf_ita,
668 &pmu_conf_gen, /* must be last */
669 NULL
670 };
671
672
673 static int pfm_end_notify_user(pfm_context_t *ctx);
674
675 static inline void
676 pfm_clear_psr_pp(void)
677 {
678 ia64_rsm(IA64_PSR_PP);
679 ia64_srlz_i();
680 }
681
682 static inline void
683 pfm_set_psr_pp(void)
684 {
685 ia64_ssm(IA64_PSR_PP);
686 ia64_srlz_i();
687 }
688
689 static inline void
690 pfm_clear_psr_up(void)
691 {
692 ia64_rsm(IA64_PSR_UP);
693 ia64_srlz_i();
694 }
695
696 static inline void
697 pfm_set_psr_up(void)
698 {
699 ia64_ssm(IA64_PSR_UP);
700 ia64_srlz_i();
701 }
702
703 static inline unsigned long
704 pfm_get_psr(void)
705 {
706 unsigned long tmp;
707 tmp = ia64_getreg(_IA64_REG_PSR);
708 ia64_srlz_i();
709 return tmp;
710 }
711
712 static inline void
713 pfm_set_psr_l(unsigned long val)
714 {
715 ia64_setreg(_IA64_REG_PSR_L, val);
716 ia64_srlz_i();
717 }
718
719 static inline void
720 pfm_freeze_pmu(void)
721 {
722 ia64_set_pmc(0,1UL);
723 ia64_srlz_d();
724 }
725
726 static inline void
727 pfm_unfreeze_pmu(void)
728 {
729 ia64_set_pmc(0,0UL);
730 ia64_srlz_d();
731 }
732
733 static inline void
734 pfm_restore_ibrs(unsigned long *ibrs, unsigned int nibrs)
735 {
736 int i;
737
738 for (i=0; i < nibrs; i++) {
739 ia64_set_ibr(i, ibrs[i]);
740 ia64_dv_serialize_instruction();
741 }
742 ia64_srlz_i();
743 }
744
745 static inline void
746 pfm_restore_dbrs(unsigned long *dbrs, unsigned int ndbrs)
747 {
748 int i;
749
750 for (i=0; i < ndbrs; i++) {
751 ia64_set_dbr(i, dbrs[i]);
752 ia64_dv_serialize_data();
753 }
754 ia64_srlz_d();
755 }
756
757 /*
758 * PMD[i] must be a counter. no check is made
759 */
760 static inline unsigned long
761 pfm_read_soft_counter(pfm_context_t *ctx, int i)
762 {
763 return ctx->ctx_pmds[i].val + (ia64_get_pmd(i) & pmu_conf->ovfl_val);
764 }
765
766 /*
767 * PMD[i] must be a counter. no check is made
768 */
769 static inline void
770 pfm_write_soft_counter(pfm_context_t *ctx, int i, unsigned long val)
771 {
772 unsigned long ovfl_val = pmu_conf->ovfl_val;
773
774 ctx->ctx_pmds[i].val = val & ~ovfl_val;
775 /*
776 * writing to unimplemented part is ignore, so we do not need to
777 * mask off top part
778 */
779 ia64_set_pmd(i, val & ovfl_val);
780 }
781
782 static pfm_msg_t *
783 pfm_get_new_msg(pfm_context_t *ctx)
784 {
785 int idx, next;
786
787 next = (ctx->ctx_msgq_tail+1) % PFM_MAX_MSGS;
788
789 DPRINT(("ctx_fd=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
790 if (next == ctx->ctx_msgq_head) return NULL;
791
792 idx = ctx->ctx_msgq_tail;
793 ctx->ctx_msgq_tail = next;
794
795 DPRINT(("ctx=%p head=%d tail=%d msg=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, idx));
796
797 return ctx->ctx_msgq+idx;
798 }
799
800 static pfm_msg_t *
801 pfm_get_next_msg(pfm_context_t *ctx)
802 {
803 pfm_msg_t *msg;
804
805 DPRINT(("ctx=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
806
807 if (PFM_CTXQ_EMPTY(ctx)) return NULL;
808
809 /*
810 * get oldest message
811 */
812 msg = ctx->ctx_msgq+ctx->ctx_msgq_head;
813
814 /*
815 * and move forward
816 */
817 ctx->ctx_msgq_head = (ctx->ctx_msgq_head+1) % PFM_MAX_MSGS;
818
819 DPRINT(("ctx=%p head=%d tail=%d type=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, msg->pfm_gen_msg.msg_type));
820
821 return msg;
822 }
823
824 static void
825 pfm_reset_msgq(pfm_context_t *ctx)
826 {
827 ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0;
828 DPRINT(("ctx=%p msgq reset\n", ctx));
829 }
830
831 static void *
832 pfm_rvmalloc(unsigned long size)
833 {
834 void *mem;
835 unsigned long addr;
836
837 size = PAGE_ALIGN(size);
838 mem = vmalloc(size);
839 if (mem) {
840 //printk("perfmon: CPU%d pfm_rvmalloc(%ld)=%p\n", smp_processor_id(), size, mem);
841 memset(mem, 0, size);
842 addr = (unsigned long)mem;
843 while (size > 0) {
844 pfm_reserve_page(addr);
845 addr+=PAGE_SIZE;
846 size-=PAGE_SIZE;
847 }
848 }
849 return mem;
850 }
851
852 static void
853 pfm_rvfree(void *mem, unsigned long size)
854 {
855 unsigned long addr;
856
857 if (mem) {
858 DPRINT(("freeing physical buffer @%p size=%lu\n", mem, size));
859 addr = (unsigned long) mem;
860 while ((long) size > 0) {
861 pfm_unreserve_page(addr);
862 addr+=PAGE_SIZE;
863 size-=PAGE_SIZE;
864 }
865 vfree(mem);
866 }
867 return;
868 }
869
870 static pfm_context_t *
871 pfm_context_alloc(int ctx_flags)
872 {
873 pfm_context_t *ctx;
874
875 /*
876 * allocate context descriptor
877 * must be able to free with interrupts disabled
878 */
879 ctx = kzalloc(sizeof(pfm_context_t), GFP_KERNEL);
880 if (ctx) {
881 DPRINT(("alloc ctx @%p\n", ctx));
882
883 /*
884 * init context protection lock
885 */
886 spin_lock_init(&ctx->ctx_lock);
887
888 /*
889 * context is unloaded
890 */
891 ctx->ctx_state = PFM_CTX_UNLOADED;
892
893 /*
894 * initialization of context's flags
895 */
896 ctx->ctx_fl_block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0;
897 ctx->ctx_fl_system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0;
898 ctx->ctx_fl_no_msg = (ctx_flags & PFM_FL_OVFL_NO_MSG) ? 1: 0;
899 /*
900 * will move to set properties
901 * ctx->ctx_fl_excl_idle = (ctx_flags & PFM_FL_EXCL_IDLE) ? 1: 0;
902 */
903
904 /*
905 * init restart semaphore to locked
906 */
907 init_completion(&ctx->ctx_restart_done);
908
909 /*
910 * activation is used in SMP only
911 */
912 ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
913 SET_LAST_CPU(ctx, -1);
914
915 /*
916 * initialize notification message queue
917 */
918 ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0;
919 init_waitqueue_head(&ctx->ctx_msgq_wait);
920 init_waitqueue_head(&ctx->ctx_zombieq);
921
922 }
923 return ctx;
924 }
925
926 static void
927 pfm_context_free(pfm_context_t *ctx)
928 {
929 if (ctx) {
930 DPRINT(("free ctx @%p\n", ctx));
931 kfree(ctx);
932 }
933 }
934
935 static void
936 pfm_mask_monitoring(struct task_struct *task)
937 {
938 pfm_context_t *ctx = PFM_GET_CTX(task);
939 unsigned long mask, val, ovfl_mask;
940 int i;
941
942 DPRINT_ovfl(("masking monitoring for [%d]\n", task_pid_nr(task)));
943
944 ovfl_mask = pmu_conf->ovfl_val;
945 /*
946 * monitoring can only be masked as a result of a valid
947 * counter overflow. In UP, it means that the PMU still
948 * has an owner. Note that the owner can be different
949 * from the current task. However the PMU state belongs
950 * to the owner.
951 * In SMP, a valid overflow only happens when task is
952 * current. Therefore if we come here, we know that
953 * the PMU state belongs to the current task, therefore
954 * we can access the live registers.
955 *
956 * So in both cases, the live register contains the owner's
957 * state. We can ONLY touch the PMU registers and NOT the PSR.
958 *
959 * As a consequence to this call, the ctx->th_pmds[] array
960 * contains stale information which must be ignored
961 * when context is reloaded AND monitoring is active (see
962 * pfm_restart).
963 */
964 mask = ctx->ctx_used_pmds[0];
965 for (i = 0; mask; i++, mask>>=1) {
966 /* skip non used pmds */
967 if ((mask & 0x1) == 0) continue;
968 val = ia64_get_pmd(i);
969
970 if (PMD_IS_COUNTING(i)) {
971 /*
972 * we rebuild the full 64 bit value of the counter
973 */
974 ctx->ctx_pmds[i].val += (val & ovfl_mask);
975 } else {
976 ctx->ctx_pmds[i].val = val;
977 }
978 DPRINT_ovfl(("pmd[%d]=0x%lx hw_pmd=0x%lx\n",
979 i,
980 ctx->ctx_pmds[i].val,
981 val & ovfl_mask));
982 }
983 /*
984 * mask monitoring by setting the privilege level to 0
985 * we cannot use psr.pp/psr.up for this, it is controlled by
986 * the user
987 *
988 * if task is current, modify actual registers, otherwise modify
989 * thread save state, i.e., what will be restored in pfm_load_regs()
990 */
991 mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER;
992 for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) {
993 if ((mask & 0x1) == 0UL) continue;
994 ia64_set_pmc(i, ctx->th_pmcs[i] & ~0xfUL);
995 ctx->th_pmcs[i] &= ~0xfUL;
996 DPRINT_ovfl(("pmc[%d]=0x%lx\n", i, ctx->th_pmcs[i]));
997 }
998 /*
999 * make all of this visible
1000 */
1001 ia64_srlz_d();
1002 }
1003
1004 /*
1005 * must always be done with task == current
1006 *
1007 * context must be in MASKED state when calling
1008 */
1009 static void
1010 pfm_restore_monitoring(struct task_struct *task)
1011 {
1012 pfm_context_t *ctx = PFM_GET_CTX(task);
1013 unsigned long mask, ovfl_mask;
1014 unsigned long psr, val;
1015 int i, is_system;
1016
1017 is_system = ctx->ctx_fl_system;
1018 ovfl_mask = pmu_conf->ovfl_val;
1019
1020 if (task != current) {
1021 printk(KERN_ERR "perfmon.%d: invalid task[%d] current[%d]\n", __LINE__, task_pid_nr(task), task_pid_nr(current));
1022 return;
1023 }
1024 if (ctx->ctx_state != PFM_CTX_MASKED) {
1025 printk(KERN_ERR "perfmon.%d: task[%d] current[%d] invalid state=%d\n", __LINE__,
1026 task_pid_nr(task), task_pid_nr(current), ctx->ctx_state);
1027 return;
1028 }
1029 psr = pfm_get_psr();
1030 /*
1031 * monitoring is masked via the PMC.
1032 * As we restore their value, we do not want each counter to
1033 * restart right away. We stop monitoring using the PSR,
1034 * restore the PMC (and PMD) and then re-establish the psr
1035 * as it was. Note that there can be no pending overflow at
1036 * this point, because monitoring was MASKED.
1037 *
1038 * system-wide session are pinned and self-monitoring
1039 */
1040 if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) {
1041 /* disable dcr pp */
1042 ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP);
1043 pfm_clear_psr_pp();
1044 } else {
1045 pfm_clear_psr_up();
1046 }
1047 /*
1048 * first, we restore the PMD
1049 */
1050 mask = ctx->ctx_used_pmds[0];
1051 for (i = 0; mask; i++, mask>>=1) {
1052 /* skip non used pmds */
1053 if ((mask & 0x1) == 0) continue;
1054
1055 if (PMD_IS_COUNTING(i)) {
1056 /*
1057 * we split the 64bit value according to
1058 * counter width
1059 */
1060 val = ctx->ctx_pmds[i].val & ovfl_mask;
1061 ctx->ctx_pmds[i].val &= ~ovfl_mask;
1062 } else {
1063 val = ctx->ctx_pmds[i].val;
1064 }
1065 ia64_set_pmd(i, val);
1066
1067 DPRINT(("pmd[%d]=0x%lx hw_pmd=0x%lx\n",
1068 i,
1069 ctx->ctx_pmds[i].val,
1070 val));
1071 }
1072 /*
1073 * restore the PMCs
1074 */
1075 mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER;
1076 for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) {
1077 if ((mask & 0x1) == 0UL) continue;
1078 ctx->th_pmcs[i] = ctx->ctx_pmcs[i];
1079 ia64_set_pmc(i, ctx->th_pmcs[i]);
1080 DPRINT(("[%d] pmc[%d]=0x%lx\n",
1081 task_pid_nr(task), i, ctx->th_pmcs[i]));
1082 }
1083 ia64_srlz_d();
1084
1085 /*
1086 * must restore DBR/IBR because could be modified while masked
1087 * XXX: need to optimize
1088 */
1089 if (ctx->ctx_fl_using_dbreg) {
1090 pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
1091 pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
1092 }
1093
1094 /*
1095 * now restore PSR
1096 */
1097 if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) {
1098 /* enable dcr pp */
1099 ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP);
1100 ia64_srlz_i();
1101 }
1102 pfm_set_psr_l(psr);
1103 }
1104
1105 static inline void
1106 pfm_save_pmds(unsigned long *pmds, unsigned long mask)
1107 {
1108 int i;
1109
1110 ia64_srlz_d();
1111
1112 for (i=0; mask; i++, mask>>=1) {
1113 if (mask & 0x1) pmds[i] = ia64_get_pmd(i);
1114 }
1115 }
1116
1117 /*
1118 * reload from thread state (used for ctxw only)
1119 */
1120 static inline void
1121 pfm_restore_pmds(unsigned long *pmds, unsigned long mask)
1122 {
1123 int i;
1124 unsigned long val, ovfl_val = pmu_conf->ovfl_val;
1125
1126 for (i=0; mask; i++, mask>>=1) {
1127 if ((mask & 0x1) == 0) continue;
1128 val = PMD_IS_COUNTING(i) ? pmds[i] & ovfl_val : pmds[i];
1129 ia64_set_pmd(i, val);
1130 }
1131 ia64_srlz_d();
1132 }
1133
1134 /*
1135 * propagate PMD from context to thread-state
1136 */
1137 static inline void
1138 pfm_copy_pmds(struct task_struct *task, pfm_context_t *ctx)
1139 {
1140 unsigned long ovfl_val = pmu_conf->ovfl_val;
1141 unsigned long mask = ctx->ctx_all_pmds[0];
1142 unsigned long val;
1143 int i;
1144
1145 DPRINT(("mask=0x%lx\n", mask));
1146
1147 for (i=0; mask; i++, mask>>=1) {
1148
1149 val = ctx->ctx_pmds[i].val;
1150
1151 /*
1152 * We break up the 64 bit value into 2 pieces
1153 * the lower bits go to the machine state in the
1154 * thread (will be reloaded on ctxsw in).
1155 * The upper part stays in the soft-counter.
1156 */
1157 if (PMD_IS_COUNTING(i)) {
1158 ctx->ctx_pmds[i].val = val & ~ovfl_val;
1159 val &= ovfl_val;
1160 }
1161 ctx->th_pmds[i] = val;
1162
1163 DPRINT(("pmd[%d]=0x%lx soft_val=0x%lx\n",
1164 i,
1165 ctx->th_pmds[i],
1166 ctx->ctx_pmds[i].val));
1167 }
1168 }
1169
1170 /*
1171 * propagate PMC from context to thread-state
1172 */
1173 static inline void
1174 pfm_copy_pmcs(struct task_struct *task, pfm_context_t *ctx)
1175 {
1176 unsigned long mask = ctx->ctx_all_pmcs[0];
1177 int i;
1178
1179 DPRINT(("mask=0x%lx\n", mask));
1180
1181 for (i=0; mask; i++, mask>>=1) {
1182 /* masking 0 with ovfl_val yields 0 */
1183 ctx->th_pmcs[i] = ctx->ctx_pmcs[i];
1184 DPRINT(("pmc[%d]=0x%lx\n", i, ctx->th_pmcs[i]));
1185 }
1186 }
1187
1188
1189
1190 static inline void
1191 pfm_restore_pmcs(unsigned long *pmcs, unsigned long mask)
1192 {
1193 int i;
1194
1195 for (i=0; mask; i++, mask>>=1) {
1196 if ((mask & 0x1) == 0) continue;
1197 ia64_set_pmc(i, pmcs[i]);
1198 }
1199 ia64_srlz_d();
1200 }
1201
1202 static inline int
1203 pfm_uuid_cmp(pfm_uuid_t a, pfm_uuid_t b)
1204 {
1205 return memcmp(a, b, sizeof(pfm_uuid_t));
1206 }
1207
1208 static inline int
1209 pfm_buf_fmt_exit(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, struct pt_regs *regs)
1210 {
1211 int ret = 0;
1212 if (fmt->fmt_exit) ret = (*fmt->fmt_exit)(task, buf, regs);
1213 return ret;
1214 }
1215
1216 static inline int
1217 pfm_buf_fmt_getsize(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, int cpu, void *arg, unsigned long *size)
1218 {
1219 int ret = 0;
1220 if (fmt->fmt_getsize) ret = (*fmt->fmt_getsize)(task, flags, cpu, arg, size);
1221 return ret;
1222 }
1223
1224
1225 static inline int
1226 pfm_buf_fmt_validate(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags,
1227 int cpu, void *arg)
1228 {
1229 int ret = 0;
1230 if (fmt->fmt_validate) ret = (*fmt->fmt_validate)(task, flags, cpu, arg);
1231 return ret;
1232 }
1233
1234 static inline int
1235 pfm_buf_fmt_init(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, unsigned int flags,
1236 int cpu, void *arg)
1237 {
1238 int ret = 0;
1239 if (fmt->fmt_init) ret = (*fmt->fmt_init)(task, buf, flags, cpu, arg);
1240 return ret;
1241 }
1242
1243 static inline int
1244 pfm_buf_fmt_restart(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
1245 {
1246 int ret = 0;
1247 if (fmt->fmt_restart) ret = (*fmt->fmt_restart)(task, ctrl, buf, regs);
1248 return ret;
1249 }
1250
1251 static inline int
1252 pfm_buf_fmt_restart_active(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
1253 {
1254 int ret = 0;
1255 if (fmt->fmt_restart_active) ret = (*fmt->fmt_restart_active)(task, ctrl, buf, regs);
1256 return ret;
1257 }
1258
1259 static pfm_buffer_fmt_t *
1260 __pfm_find_buffer_fmt(pfm_uuid_t uuid)
1261 {
1262 struct list_head * pos;
1263 pfm_buffer_fmt_t * entry;
1264
1265 list_for_each(pos, &pfm_buffer_fmt_list) {
1266 entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list);
1267 if (pfm_uuid_cmp(uuid, entry->fmt_uuid) == 0)
1268 return entry;
1269 }
1270 return NULL;
1271 }
1272
1273 /*
1274 * find a buffer format based on its uuid
1275 */
1276 static pfm_buffer_fmt_t *
1277 pfm_find_buffer_fmt(pfm_uuid_t uuid)
1278 {
1279 pfm_buffer_fmt_t * fmt;
1280 spin_lock(&pfm_buffer_fmt_lock);
1281 fmt = __pfm_find_buffer_fmt(uuid);
1282 spin_unlock(&pfm_buffer_fmt_lock);
1283 return fmt;
1284 }
1285
1286 int
1287 pfm_register_buffer_fmt(pfm_buffer_fmt_t *fmt)
1288 {
1289 int ret = 0;
1290
1291 /* some sanity checks */
1292 if (fmt == NULL || fmt->fmt_name == NULL) return -EINVAL;
1293
1294 /* we need at least a handler */
1295 if (fmt->fmt_handler == NULL) return -EINVAL;
1296
1297 /*
1298 * XXX: need check validity of fmt_arg_size
1299 */
1300
1301 spin_lock(&pfm_buffer_fmt_lock);
1302
1303 if (__pfm_find_buffer_fmt(fmt->fmt_uuid)) {
1304 printk(KERN_ERR "perfmon: duplicate sampling format: %s\n", fmt->fmt_name);
1305 ret = -EBUSY;
1306 goto out;
1307 }
1308 list_add(&fmt->fmt_list, &pfm_buffer_fmt_list);
1309 printk(KERN_INFO "perfmon: added sampling format %s\n", fmt->fmt_name);
1310
1311 out:
1312 spin_unlock(&pfm_buffer_fmt_lock);
1313 return ret;
1314 }
1315 EXPORT_SYMBOL(pfm_register_buffer_fmt);
1316
1317 int
1318 pfm_unregister_buffer_fmt(pfm_uuid_t uuid)
1319 {
1320 pfm_buffer_fmt_t *fmt;
1321 int ret = 0;
1322
1323 spin_lock(&pfm_buffer_fmt_lock);
1324
1325 fmt = __pfm_find_buffer_fmt(uuid);
1326 if (!fmt) {
1327 printk(KERN_ERR "perfmon: cannot unregister format, not found\n");
1328 ret = -EINVAL;
1329 goto out;
1330 }
1331 list_del_init(&fmt->fmt_list);
1332 printk(KERN_INFO "perfmon: removed sampling format: %s\n", fmt->fmt_name);
1333
1334 out:
1335 spin_unlock(&pfm_buffer_fmt_lock);
1336 return ret;
1337
1338 }
1339 EXPORT_SYMBOL(pfm_unregister_buffer_fmt);
1340
1341 extern void update_pal_halt_status(int);
1342
1343 static int
1344 pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu)
1345 {
1346 unsigned long flags;
1347 /*
1348 * validity checks on cpu_mask have been done upstream
1349 */
1350 LOCK_PFS(flags);
1351
1352 DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
1353 pfm_sessions.pfs_sys_sessions,
1354 pfm_sessions.pfs_task_sessions,
1355 pfm_sessions.pfs_sys_use_dbregs,
1356 is_syswide,
1357 cpu));
1358
1359 if (is_syswide) {
1360 /*
1361 * cannot mix system wide and per-task sessions
1362 */
1363 if (pfm_sessions.pfs_task_sessions > 0UL) {
1364 DPRINT(("system wide not possible, %u conflicting task_sessions\n",
1365 pfm_sessions.pfs_task_sessions));
1366 goto abort;
1367 }
1368
1369 if (pfm_sessions.pfs_sys_session[cpu]) goto error_conflict;
1370
1371 DPRINT(("reserving system wide session on CPU%u currently on CPU%u\n", cpu, smp_processor_id()));
1372
1373 pfm_sessions.pfs_sys_session[cpu] = task;
1374
1375 pfm_sessions.pfs_sys_sessions++ ;
1376
1377 } else {
1378 if (pfm_sessions.pfs_sys_sessions) goto abort;
1379 pfm_sessions.pfs_task_sessions++;
1380 }
1381
1382 DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
1383 pfm_sessions.pfs_sys_sessions,
1384 pfm_sessions.pfs_task_sessions,
1385 pfm_sessions.pfs_sys_use_dbregs,
1386 is_syswide,
1387 cpu));
1388
1389 /*
1390 * disable default_idle() to go to PAL_HALT
1391 */
1392 update_pal_halt_status(0);
1393
1394 UNLOCK_PFS(flags);
1395
1396 return 0;
1397
1398 error_conflict:
1399 DPRINT(("system wide not possible, conflicting session [%d] on CPU%d\n",
1400 task_pid_nr(pfm_sessions.pfs_sys_session[cpu]),
1401 cpu));
1402 abort:
1403 UNLOCK_PFS(flags);
1404
1405 return -EBUSY;
1406
1407 }
1408
1409 static int
1410 pfm_unreserve_session(pfm_context_t *ctx, int is_syswide, unsigned int cpu)
1411 {
1412 unsigned long flags;
1413 /*
1414 * validity checks on cpu_mask have been done upstream
1415 */
1416 LOCK_PFS(flags);
1417
1418 DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
1419 pfm_sessions.pfs_sys_sessions,
1420 pfm_sessions.pfs_task_sessions,
1421 pfm_sessions.pfs_sys_use_dbregs,
1422 is_syswide,
1423 cpu));
1424
1425
1426 if (is_syswide) {
1427 pfm_sessions.pfs_sys_session[cpu] = NULL;
1428 /*
1429 * would not work with perfmon+more than one bit in cpu_mask
1430 */
1431 if (ctx && ctx->ctx_fl_using_dbreg) {
1432 if (pfm_sessions.pfs_sys_use_dbregs == 0) {
1433 printk(KERN_ERR "perfmon: invalid release for ctx %p sys_use_dbregs=0\n", ctx);
1434 } else {
1435 pfm_sessions.pfs_sys_use_dbregs--;
1436 }
1437 }
1438 pfm_sessions.pfs_sys_sessions--;
1439 } else {
1440 pfm_sessions.pfs_task_sessions--;
1441 }
1442 DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
1443 pfm_sessions.pfs_sys_sessions,
1444 pfm_sessions.pfs_task_sessions,
1445 pfm_sessions.pfs_sys_use_dbregs,
1446 is_syswide,
1447 cpu));
1448
1449 /*
1450 * if possible, enable default_idle() to go into PAL_HALT
1451 */
1452 if (pfm_sessions.pfs_task_sessions == 0 && pfm_sessions.pfs_sys_sessions == 0)
1453 update_pal_halt_status(1);
1454
1455 UNLOCK_PFS(flags);
1456
1457 return 0;
1458 }
1459
1460 /*
1461 * removes virtual mapping of the sampling buffer.
1462 * IMPORTANT: cannot be called with interrupts disable, e.g. inside
1463 * a PROTECT_CTX() section.
1464 */
1465 static int
1466 pfm_remove_smpl_mapping(struct task_struct *task, void *vaddr, unsigned long size)
1467 {
1468 int r;
1469
1470 /* sanity checks */
1471 if (task->mm == NULL || size == 0UL || vaddr == NULL) {
1472 printk(KERN_ERR "perfmon: pfm_remove_smpl_mapping [%d] invalid context mm=%p\n", task_pid_nr(task), task->mm);
1473 return -EINVAL;
1474 }
1475
1476 DPRINT(("smpl_vaddr=%p size=%lu\n", vaddr, size));
1477
1478 /*
1479 * does the actual unmapping
1480 */
1481 down_write(&task->mm->mmap_sem);
1482
1483 DPRINT(("down_write done smpl_vaddr=%p size=%lu\n", vaddr, size));
1484
1485 r = pfm_do_munmap(task->mm, (unsigned long)vaddr, size, 0);
1486
1487 up_write(&task->mm->mmap_sem);
1488 if (r !=0) {
1489 printk(KERN_ERR "perfmon: [%d] unable to unmap sampling buffer @%p size=%lu\n", task_pid_nr(task), vaddr, size);
1490 }
1491
1492 DPRINT(("do_unmap(%p, %lu)=%d\n", vaddr, size, r));
1493
1494 return 0;
1495 }
1496
1497 /*
1498 * free actual physical storage used by sampling buffer
1499 */
1500 #if 0
1501 static int
1502 pfm_free_smpl_buffer(pfm_context_t *ctx)
1503 {
1504 pfm_buffer_fmt_t *fmt;
1505
1506 if (ctx->ctx_smpl_hdr == NULL) goto invalid_free;
1507
1508 /*
1509 * we won't use the buffer format anymore
1510 */
1511 fmt = ctx->ctx_buf_fmt;
1512
1513 DPRINT(("sampling buffer @%p size %lu vaddr=%p\n",
1514 ctx->ctx_smpl_hdr,
1515 ctx->ctx_smpl_size,
1516 ctx->ctx_smpl_vaddr));
1517
1518 pfm_buf_fmt_exit(fmt, current, NULL, NULL);
1519
1520 /*
1521 * free the buffer
1522 */
1523 pfm_rvfree(ctx->ctx_smpl_hdr, ctx->ctx_smpl_size);
1524
1525 ctx->ctx_smpl_hdr = NULL;
1526 ctx->ctx_smpl_size = 0UL;
1527
1528 return 0;
1529
1530 invalid_free:
1531 printk(KERN_ERR "perfmon: pfm_free_smpl_buffer [%d] no buffer\n", task_pid_nr(current));
1532 return -EINVAL;
1533 }
1534 #endif
1535
1536 static inline void
1537 pfm_exit_smpl_buffer(pfm_buffer_fmt_t *fmt)
1538 {
1539 if (fmt == NULL) return;
1540
1541 pfm_buf_fmt_exit(fmt, current, NULL, NULL);
1542
1543 }
1544
1545 /*
1546 * pfmfs should _never_ be mounted by userland - too much of security hassle,
1547 * no real gain from having the whole whorehouse mounted. So we don't need
1548 * any operations on the root directory. However, we need a non-trivial
1549 * d_name - pfm: will go nicely and kill the special-casing in procfs.
1550 */
1551 static struct vfsmount *pfmfs_mnt;
1552
1553 static int __init
1554 init_pfm_fs(void)
1555 {
1556 int err = register_filesystem(&pfm_fs_type);
1557 if (!err) {
1558 pfmfs_mnt = kern_mount(&pfm_fs_type);
1559 err = PTR_ERR(pfmfs_mnt);
1560 if (IS_ERR(pfmfs_mnt))
1561 unregister_filesystem(&pfm_fs_type);
1562 else
1563 err = 0;
1564 }
1565 return err;
1566 }
1567
1568 static ssize_t
1569 pfm_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos)
1570 {
1571 pfm_context_t *ctx;
1572 pfm_msg_t *msg;
1573 ssize_t ret;
1574 unsigned long flags;
1575 DECLARE_WAITQUEUE(wait, current);
1576 if (PFM_IS_FILE(filp) == 0) {
1577 printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", task_pid_nr(current));
1578 return -EINVAL;
1579 }
1580
1581 ctx = (pfm_context_t *)filp->private_data;
1582 if (ctx == NULL) {
1583 printk(KERN_ERR "perfmon: pfm_read: NULL ctx [%d]\n", task_pid_nr(current));
1584 return -EINVAL;
1585 }
1586
1587 /*
1588 * check even when there is no message
1589 */
1590 if (size < sizeof(pfm_msg_t)) {
1591 DPRINT(("message is too small ctx=%p (>=%ld)\n", ctx, sizeof(pfm_msg_t)));
1592 return -EINVAL;
1593 }
1594
1595 PROTECT_CTX(ctx, flags);
1596
1597 /*
1598 * put ourselves on the wait queue
1599 */
1600 add_wait_queue(&ctx->ctx_msgq_wait, &wait);
1601
1602
1603 for(;;) {
1604 /*
1605 * check wait queue
1606 */
1607
1608 set_current_state(TASK_INTERRUPTIBLE);
1609
1610 DPRINT(("head=%d tail=%d\n", ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
1611
1612 ret = 0;
1613 if(PFM_CTXQ_EMPTY(ctx) == 0) break;
1614
1615 UNPROTECT_CTX(ctx, flags);
1616
1617 /*
1618 * check non-blocking read
1619 */
1620 ret = -EAGAIN;
1621 if(filp->f_flags & O_NONBLOCK) break;
1622
1623 /*
1624 * check pending signals
1625 */
1626 if(signal_pending(current)) {
1627 ret = -EINTR;
1628 break;
1629 }
1630 /*
1631 * no message, so wait
1632 */
1633 schedule();
1634
1635 PROTECT_CTX(ctx, flags);
1636 }
1637 DPRINT(("[%d] back to running ret=%ld\n", task_pid_nr(current), ret));
1638 set_current_state(TASK_RUNNING);
1639 remove_wait_queue(&ctx->ctx_msgq_wait, &wait);
1640
1641 if (ret < 0) goto abort;
1642
1643 ret = -EINVAL;
1644 msg = pfm_get_next_msg(ctx);
1645 if (msg == NULL) {
1646 printk(KERN_ERR "perfmon: pfm_read no msg for ctx=%p [%d]\n", ctx, task_pid_nr(current));
1647 goto abort_locked;
1648 }
1649
1650 DPRINT(("fd=%d type=%d\n", msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type));
1651
1652 ret = -EFAULT;
1653 if(copy_to_user(buf, msg, sizeof(pfm_msg_t)) == 0) ret = sizeof(pfm_msg_t);
1654
1655 abort_locked:
1656 UNPROTECT_CTX(ctx, flags);
1657 abort:
1658 return ret;
1659 }
1660
1661 static ssize_t
1662 pfm_write(struct file *file, const char __user *ubuf,
1663 size_t size, loff_t *ppos)
1664 {
1665 DPRINT(("pfm_write called\n"));
1666 return -EINVAL;
1667 }
1668
1669 static unsigned int
1670 pfm_poll(struct file *filp, poll_table * wait)
1671 {
1672 pfm_context_t *ctx;
1673 unsigned long flags;
1674 unsigned int mask = 0;
1675
1676 if (PFM_IS_FILE(filp) == 0) {
1677 printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", task_pid_nr(current));
1678 return 0;
1679 }
1680
1681 ctx = (pfm_context_t *)filp->private_data;
1682 if (ctx == NULL) {
1683 printk(KERN_ERR "perfmon: pfm_poll: NULL ctx [%d]\n", task_pid_nr(current));
1684 return 0;
1685 }
1686
1687
1688 DPRINT(("pfm_poll ctx_fd=%d before poll_wait\n", ctx->ctx_fd));
1689
1690 poll_wait(filp, &ctx->ctx_msgq_wait, wait);
1691
1692 PROTECT_CTX(ctx, flags);
1693
1694 if (PFM_CTXQ_EMPTY(ctx) == 0)
1695 mask = POLLIN | POLLRDNORM;
1696
1697 UNPROTECT_CTX(ctx, flags);
1698
1699 DPRINT(("pfm_poll ctx_fd=%d mask=0x%x\n", ctx->ctx_fd, mask));
1700
1701 return mask;
1702 }
1703
1704 static int
1705 pfm_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
1706 {
1707 DPRINT(("pfm_ioctl called\n"));
1708 return -EINVAL;
1709 }
1710
1711 /*
1712 * interrupt cannot be masked when coming here
1713 */
1714 static inline int
1715 pfm_do_fasync(int fd, struct file *filp, pfm_context_t *ctx, int on)
1716 {
1717 int ret;
1718
1719 ret = fasync_helper (fd, filp, on, &ctx->ctx_async_queue);
1720
1721 DPRINT(("pfm_fasync called by [%d] on ctx_fd=%d on=%d async_queue=%p ret=%d\n",
1722 task_pid_nr(current),
1723 fd,
1724 on,
1725 ctx->ctx_async_queue, ret));
1726
1727 return ret;
1728 }
1729
1730 static int
1731 pfm_fasync(int fd, struct file *filp, int on)
1732 {
1733 pfm_context_t *ctx;
1734 int ret;
1735
1736 if (PFM_IS_FILE(filp) == 0) {
1737 printk(KERN_ERR "perfmon: pfm_fasync bad magic [%d]\n", task_pid_nr(current));
1738 return -EBADF;
1739 }
1740
1741 ctx = (pfm_context_t *)filp->private_data;
1742 if (ctx == NULL) {
1743 printk(KERN_ERR "perfmon: pfm_fasync NULL ctx [%d]\n", task_pid_nr(current));
1744 return -EBADF;
1745 }
1746 /*
1747 * we cannot mask interrupts during this call because this may
1748 * may go to sleep if memory is not readily avalaible.
1749 *
1750 * We are protected from the conetxt disappearing by the get_fd()/put_fd()
1751 * done in caller. Serialization of this function is ensured by caller.
1752 */
1753 ret = pfm_do_fasync(fd, filp, ctx, on);
1754
1755
1756 DPRINT(("pfm_fasync called on ctx_fd=%d on=%d async_queue=%p ret=%d\n",
1757 fd,
1758 on,
1759 ctx->ctx_async_queue, ret));
1760
1761 return ret;
1762 }
1763
1764 #ifdef CONFIG_SMP
1765 /*
1766 * this function is exclusively called from pfm_close().
1767 * The context is not protected at that time, nor are interrupts
1768 * on the remote CPU. That's necessary to avoid deadlocks.
1769 */
1770 static void
1771 pfm_syswide_force_stop(void *info)
1772 {
1773 pfm_context_t *ctx = (pfm_context_t *)info;
1774 struct pt_regs *regs = task_pt_regs(current);
1775 struct task_struct *owner;
1776 unsigned long flags;
1777 int ret;
1778
1779 if (ctx->ctx_cpu != smp_processor_id()) {
1780 printk(KERN_ERR "perfmon: pfm_syswide_force_stop for CPU%d but on CPU%d\n",
1781 ctx->ctx_cpu,
1782 smp_processor_id());
1783 return;
1784 }
1785 owner = GET_PMU_OWNER();
1786 if (owner != ctx->ctx_task) {
1787 printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected owner [%d] instead of [%d]\n",
1788 smp_processor_id(),
1789 task_pid_nr(owner), task_pid_nr(ctx->ctx_task));
1790 return;
1791 }
1792 if (GET_PMU_CTX() != ctx) {
1793 printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected ctx %p instead of %p\n",
1794 smp_processor_id(),
1795 GET_PMU_CTX(), ctx);
1796 return;
1797 }
1798
1799 DPRINT(("on CPU%d forcing system wide stop for [%d]\n", smp_processor_id(), task_pid_nr(ctx->ctx_task)));
1800 /*
1801 * the context is already protected in pfm_close(), we simply
1802 * need to mask interrupts to avoid a PMU interrupt race on
1803 * this CPU
1804 */
1805 local_irq_save(flags);
1806
1807 ret = pfm_context_unload(ctx, NULL, 0, regs);
1808 if (ret) {
1809 DPRINT(("context_unload returned %d\n", ret));
1810 }
1811
1812 /*
1813 * unmask interrupts, PMU interrupts are now spurious here
1814 */
1815 local_irq_restore(flags);
1816 }
1817
1818 static void
1819 pfm_syswide_cleanup_other_cpu(pfm_context_t *ctx)
1820 {
1821 int ret;
1822
1823 DPRINT(("calling CPU%d for cleanup\n", ctx->ctx_cpu));
1824 ret = smp_call_function_single(ctx->ctx_cpu, pfm_syswide_force_stop, ctx, 1);
1825 DPRINT(("called CPU%d for cleanup ret=%d\n", ctx->ctx_cpu, ret));
1826 }
1827 #endif /* CONFIG_SMP */
1828
1829 /*
1830 * called for each close(). Partially free resources.
1831 * When caller is self-monitoring, the context is unloaded.
1832 */
1833 static int
1834 pfm_flush(struct file *filp, fl_owner_t id)
1835 {
1836 pfm_context_t *ctx;
1837 struct task_struct *task;
1838 struct pt_regs *regs;
1839 unsigned long flags;
1840 unsigned long smpl_buf_size = 0UL;
1841 void *smpl_buf_vaddr = NULL;
1842 int state, is_system;
1843
1844 if (PFM_IS_FILE(filp) == 0) {
1845 DPRINT(("bad magic for\n"));
1846 return -EBADF;
1847 }
1848
1849 ctx = (pfm_context_t *)filp->private_data;
1850 if (ctx == NULL) {
1851 printk(KERN_ERR "perfmon: pfm_flush: NULL ctx [%d]\n", task_pid_nr(current));
1852 return -EBADF;
1853 }
1854
1855 /*
1856 * remove our file from the async queue, if we use this mode.
1857 * This can be done without the context being protected. We come
1858 * here when the context has become unreachable by other tasks.
1859 *
1860 * We may still have active monitoring at this point and we may
1861 * end up in pfm_overflow_handler(). However, fasync_helper()
1862 * operates with interrupts disabled and it cleans up the
1863 * queue. If the PMU handler is called prior to entering
1864 * fasync_helper() then it will send a signal. If it is
1865 * invoked after, it will find an empty queue and no
1866 * signal will be sent. In both case, we are safe
1867 */
1868 PROTECT_CTX(ctx, flags);
1869
1870 state = ctx->ctx_state;
1871 is_system = ctx->ctx_fl_system;
1872
1873 task = PFM_CTX_TASK(ctx);
1874 regs = task_pt_regs(task);
1875
1876 DPRINT(("ctx_state=%d is_current=%d\n",
1877 state,
1878 task == current ? 1 : 0));
1879
1880 /*
1881 * if state == UNLOADED, then task is NULL
1882 */
1883
1884 /*
1885 * we must stop and unload because we are losing access to the context.
1886 */
1887 if (task == current) {
1888 #ifdef CONFIG_SMP
1889 /*
1890 * the task IS the owner but it migrated to another CPU: that's bad
1891 * but we must handle this cleanly. Unfortunately, the kernel does
1892 * not provide a mechanism to block migration (while the context is loaded).
1893 *
1894 * We need to release the resource on the ORIGINAL cpu.
1895 */
1896 if (is_system && ctx->ctx_cpu != smp_processor_id()) {
1897
1898 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
1899 /*
1900 * keep context protected but unmask interrupt for IPI
1901 */
1902 local_irq_restore(flags);
1903
1904 pfm_syswide_cleanup_other_cpu(ctx);
1905
1906 /*
1907 * restore interrupt masking
1908 */
1909 local_irq_save(flags);
1910
1911 /*
1912 * context is unloaded at this point
1913 */
1914 } else
1915 #endif /* CONFIG_SMP */
1916 {
1917
1918 DPRINT(("forcing unload\n"));
1919 /*
1920 * stop and unload, returning with state UNLOADED
1921 * and session unreserved.
1922 */
1923 pfm_context_unload(ctx, NULL, 0, regs);
1924
1925 DPRINT(("ctx_state=%d\n", ctx->ctx_state));
1926 }
1927 }
1928
1929 /*
1930 * remove virtual mapping, if any, for the calling task.
1931 * cannot reset ctx field until last user is calling close().
1932 *
1933 * ctx_smpl_vaddr must never be cleared because it is needed
1934 * by every task with access to the context
1935 *
1936 * When called from do_exit(), the mm context is gone already, therefore
1937 * mm is NULL, i.e., the VMA is already gone and we do not have to
1938 * do anything here
1939 */
1940 if (ctx->ctx_smpl_vaddr && current->mm) {
1941 smpl_buf_vaddr = ctx->ctx_smpl_vaddr;
1942 smpl_buf_size = ctx->ctx_smpl_size;
1943 }
1944
1945 UNPROTECT_CTX(ctx, flags);
1946
1947 /*
1948 * if there was a mapping, then we systematically remove it
1949 * at this point. Cannot be done inside critical section
1950 * because some VM function reenables interrupts.
1951 *
1952 */
1953 if (smpl_buf_vaddr) pfm_remove_smpl_mapping(current, smpl_buf_vaddr, smpl_buf_size);
1954
1955 return 0;
1956 }
1957 /*
1958 * called either on explicit close() or from exit_files().
1959 * Only the LAST user of the file gets to this point, i.e., it is
1960 * called only ONCE.
1961 *
1962 * IMPORTANT: we get called ONLY when the refcnt on the file gets to zero
1963 * (fput()),i.e, last task to access the file. Nobody else can access the
1964 * file at this point.
1965 *
1966 * When called from exit_files(), the VMA has been freed because exit_mm()
1967 * is executed before exit_files().
1968 *
1969 * When called from exit_files(), the current task is not yet ZOMBIE but we
1970 * flush the PMU state to the context.
1971 */
1972 static int
1973 pfm_close(struct inode *inode, struct file *filp)
1974 {
1975 pfm_context_t *ctx;
1976 struct task_struct *task;
1977 struct pt_regs *regs;
1978 DECLARE_WAITQUEUE(wait, current);
1979 unsigned long flags;
1980 unsigned long smpl_buf_size = 0UL;
1981 void *smpl_buf_addr = NULL;
1982 int free_possible = 1;
1983 int state, is_system;
1984
1985 DPRINT(("pfm_close called private=%p\n", filp->private_data));
1986
1987 if (PFM_IS_FILE(filp) == 0) {
1988 DPRINT(("bad magic\n"));
1989 return -EBADF;
1990 }
1991
1992 ctx = (pfm_context_t *)filp->private_data;
1993 if (ctx == NULL) {
1994 printk(KERN_ERR "perfmon: pfm_close: NULL ctx [%d]\n", task_pid_nr(current));
1995 return -EBADF;
1996 }
1997
1998 PROTECT_CTX(ctx, flags);
1999
2000 state = ctx->ctx_state;
2001 is_system = ctx->ctx_fl_system;
2002
2003 task = PFM_CTX_TASK(ctx);
2004 regs = task_pt_regs(task);
2005
2006 DPRINT(("ctx_state=%d is_current=%d\n",
2007 state,
2008 task == current ? 1 : 0));
2009
2010 /*
2011 * if task == current, then pfm_flush() unloaded the context
2012 */
2013 if (state == PFM_CTX_UNLOADED) goto doit;
2014
2015 /*
2016 * context is loaded/masked and task != current, we need to
2017 * either force an unload or go zombie
2018 */
2019
2020 /*
2021 * The task is currently blocked or will block after an overflow.
2022 * we must force it to wakeup to get out of the
2023 * MASKED state and transition to the unloaded state by itself.
2024 *
2025 * This situation is only possible for per-task mode
2026 */
2027 if (state == PFM_CTX_MASKED && CTX_OVFL_NOBLOCK(ctx) == 0) {
2028
2029 /*
2030 * set a "partial" zombie state to be checked
2031 * upon return from down() in pfm_handle_work().
2032 *
2033 * We cannot use the ZOMBIE state, because it is checked
2034 * by pfm_load_regs() which is called upon wakeup from down().
2035 * In such case, it would free the context and then we would
2036 * return to pfm_handle_work() which would access the
2037 * stale context. Instead, we set a flag invisible to pfm_load_regs()
2038 * but visible to pfm_handle_work().
2039 *
2040 * For some window of time, we have a zombie context with
2041 * ctx_state = MASKED and not ZOMBIE
2042 */
2043 ctx->ctx_fl_going_zombie = 1;
2044
2045 /*
2046 * force task to wake up from MASKED state
2047 */
2048 complete(&ctx->ctx_restart_done);
2049
2050 DPRINT(("waking up ctx_state=%d\n", state));
2051
2052 /*
2053 * put ourself to sleep waiting for the other
2054 * task to report completion
2055 *
2056 * the context is protected by mutex, therefore there
2057 * is no risk of being notified of completion before
2058 * begin actually on the waitq.
2059 */
2060 set_current_state(TASK_INTERRUPTIBLE);
2061 add_wait_queue(&ctx->ctx_zombieq, &wait);
2062
2063 UNPROTECT_CTX(ctx, flags);
2064
2065 /*
2066 * XXX: check for signals :
2067 * - ok for explicit close
2068 * - not ok when coming from exit_files()
2069 */
2070 schedule();
2071
2072
2073 PROTECT_CTX(ctx, flags);
2074
2075
2076 remove_wait_queue(&ctx->ctx_zombieq, &wait);
2077 set_current_state(TASK_RUNNING);
2078
2079 /*
2080 * context is unloaded at this point
2081 */
2082 DPRINT(("after zombie wakeup ctx_state=%d for\n", state));
2083 }
2084 else if (task != current) {
2085 #ifdef CONFIG_SMP
2086 /*
2087 * switch context to zombie state
2088 */
2089 ctx->ctx_state = PFM_CTX_ZOMBIE;
2090
2091 DPRINT(("zombie ctx for [%d]\n", task_pid_nr(task)));
2092 /*
2093 * cannot free the context on the spot. deferred until
2094 * the task notices the ZOMBIE state
2095 */
2096 free_possible = 0;
2097 #else
2098 pfm_context_unload(ctx, NULL, 0, regs);
2099 #endif
2100 }
2101
2102 doit:
2103 /* reload state, may have changed during opening of critical section */
2104 state = ctx->ctx_state;
2105
2106 /*
2107 * the context is still attached to a task (possibly current)
2108 * we cannot destroy it right now
2109 */
2110
2111 /*
2112 * we must free the sampling buffer right here because
2113 * we cannot rely on it being cleaned up later by the
2114 * monitored task. It is not possible to free vmalloc'ed
2115 * memory in pfm_load_regs(). Instead, we remove the buffer
2116 * now. should there be subsequent PMU overflow originally
2117 * meant for sampling, the will be converted to spurious
2118 * and that's fine because the monitoring tools is gone anyway.
2119 */
2120 if (ctx->ctx_smpl_hdr) {
2121 smpl_buf_addr = ctx->ctx_smpl_hdr;
2122 smpl_buf_size = ctx->ctx_smpl_size;
2123 /* no more sampling */
2124 ctx->ctx_smpl_hdr = NULL;
2125 ctx->ctx_fl_is_sampling = 0;
2126 }
2127
2128 DPRINT(("ctx_state=%d free_possible=%d addr=%p size=%lu\n",
2129 state,
2130 free_possible,
2131 smpl_buf_addr,
2132 smpl_buf_size));
2133
2134 if (smpl_buf_addr) pfm_exit_smpl_buffer(ctx->ctx_buf_fmt);
2135
2136 /*
2137 * UNLOADED that the session has already been unreserved.
2138 */
2139 if (state == PFM_CTX_ZOMBIE) {
2140 pfm_unreserve_session(ctx, ctx->ctx_fl_system , ctx->ctx_cpu);
2141 }
2142
2143 /*
2144 * disconnect file descriptor from context must be done
2145 * before we unlock.
2146 */
2147 filp->private_data = NULL;
2148
2149 /*
2150 * if we free on the spot, the context is now completely unreachable
2151 * from the callers side. The monitored task side is also cut, so we
2152 * can freely cut.
2153 *
2154 * If we have a deferred free, only the caller side is disconnected.
2155 */
2156 UNPROTECT_CTX(ctx, flags);
2157
2158 /*
2159 * All memory free operations (especially for vmalloc'ed memory)
2160 * MUST be done with interrupts ENABLED.
2161 */
2162 if (smpl_buf_addr) pfm_rvfree(smpl_buf_addr, smpl_buf_size);
2163
2164 /*
2165 * return the memory used by the context
2166 */
2167 if (free_possible) pfm_context_free(ctx);
2168
2169 return 0;
2170 }
2171
2172 static int
2173 pfm_no_open(struct inode *irrelevant, struct file *dontcare)
2174 {
2175 DPRINT(("pfm_no_open called\n"));
2176 return -ENXIO;
2177 }
2178
2179
2180
2181 static const struct file_operations pfm_file_ops = {
2182 .llseek = no_llseek,
2183 .read = pfm_read,
2184 .write = pfm_write,
2185 .poll = pfm_poll,
2186 .ioctl = pfm_ioctl,
2187 .open = pfm_no_open, /* special open code to disallow open via /proc */
2188 .fasync = pfm_fasync,
2189 .release = pfm_close,
2190 .flush = pfm_flush
2191 };
2192
2193 static int
2194 pfmfs_delete_dentry(struct dentry *dentry)
2195 {
2196 return 1;
2197 }
2198
2199 static const struct dentry_operations pfmfs_dentry_operations = {
2200 .d_delete = pfmfs_delete_dentry,
2201 };
2202
2203
2204 static struct file *
2205 pfm_alloc_file(pfm_context_t *ctx)
2206 {
2207 struct file *file;
2208 struct inode *inode;
2209 struct dentry *dentry;
2210 char name[32];
2211 struct qstr this;
2212
2213 /*
2214 * allocate a new inode
2215 */
2216 inode = new_inode(pfmfs_mnt->mnt_sb);
2217 if (!inode)
2218 return ERR_PTR(-ENOMEM);
2219
2220 DPRINT(("new inode ino=%ld @%p\n", inode->i_ino, inode));
2221
2222 inode->i_mode = S_IFCHR|S_IRUGO;
2223 inode->i_uid = current_fsuid();
2224 inode->i_gid = current_fsgid();
2225
2226 sprintf(name, "[%lu]", inode->i_ino);
2227 this.name = name;
2228 this.len = strlen(name);
2229 this.hash = inode->i_ino;
2230
2231 /*
2232 * allocate a new dcache entry
2233 */
2234 dentry = d_alloc(pfmfs_mnt->mnt_sb->s_root, &this);
2235 if (!dentry) {
2236 iput(inode);
2237 return ERR_PTR(-ENOMEM);
2238 }
2239
2240 dentry->d_op = &pfmfs_dentry_operations;
2241 d_add(dentry, inode);
2242
2243 file = alloc_file(pfmfs_mnt, dentry, FMODE_READ, &pfm_file_ops);
2244 if (!file) {
2245 dput(dentry);
2246 return ERR_PTR(-ENFILE);
2247 }
2248
2249 file->f_flags = O_RDONLY;
2250 file->private_data = ctx;
2251
2252 return file;
2253 }
2254
2255 static int
2256 pfm_remap_buffer(struct vm_area_struct *vma, unsigned long buf, unsigned long addr, unsigned long size)
2257 {
2258 DPRINT(("CPU%d buf=0x%lx addr=0x%lx size=%ld\n", smp_processor_id(), buf, addr, size));
2259
2260 while (size > 0) {
2261 unsigned long pfn = ia64_tpa(buf) >> PAGE_SHIFT;
2262
2263
2264 if (remap_pfn_range(vma, addr, pfn, PAGE_SIZE, PAGE_READONLY))
2265 return -ENOMEM;
2266
2267 addr += PAGE_SIZE;
2268 buf += PAGE_SIZE;
2269 size -= PAGE_SIZE;
2270 }
2271 return 0;
2272 }
2273
2274 /*
2275 * allocate a sampling buffer and remaps it into the user address space of the task
2276 */
2277 static int
2278 pfm_smpl_buffer_alloc(struct task_struct *task, struct file *filp, pfm_context_t *ctx, unsigned long rsize, void **user_vaddr)
2279 {
2280 struct mm_struct *mm = task->mm;
2281 struct vm_area_struct *vma = NULL;
2282 unsigned long size;
2283 void *smpl_buf;
2284
2285
2286 /*
2287 * the fixed header + requested size and align to page boundary
2288 */
2289 size = PAGE_ALIGN(rsize);
2290
2291 DPRINT(("sampling buffer rsize=%lu size=%lu bytes\n", rsize, size));
2292
2293 /*
2294 * check requested size to avoid Denial-of-service attacks
2295 * XXX: may have to refine this test
2296 * Check against address space limit.
2297 *
2298 * if ((mm->total_vm << PAGE_SHIFT) + len> task->rlim[RLIMIT_AS].rlim_cur)
2299 * return -ENOMEM;
2300 */
2301 if (size > task->signal->rlim[RLIMIT_MEMLOCK].rlim_cur)
2302 return -ENOMEM;
2303
2304 /*
2305 * We do the easy to undo allocations first.
2306 *
2307 * pfm_rvmalloc(), clears the buffer, so there is no leak
2308 */
2309 smpl_buf = pfm_rvmalloc(size);
2310 if (smpl_buf == NULL) {
2311 DPRINT(("Can't allocate sampling buffer\n"));
2312 return -ENOMEM;
2313 }
2314
2315 DPRINT(("smpl_buf @%p\n", smpl_buf));
2316
2317 /* allocate vma */
2318 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
2319 if (!vma) {
2320 DPRINT(("Cannot allocate vma\n"));
2321 goto error_kmem;
2322 }
2323
2324 /*
2325 * partially initialize the vma for the sampling buffer
2326 */
2327 vma->vm_mm = mm;
2328 vma->vm_file = filp;
2329 vma->vm_flags = VM_READ| VM_MAYREAD |VM_RESERVED;
2330 vma->vm_page_prot = PAGE_READONLY; /* XXX may need to change */
2331
2332 /*
2333 * Now we have everything we need and we can initialize
2334 * and connect all the data structures
2335 */
2336
2337 ctx->ctx_smpl_hdr = smpl_buf;
2338 ctx->ctx_smpl_size = size; /* aligned size */
2339
2340 /*
2341 * Let's do the difficult operations next.
2342 *
2343 * now we atomically find some area in the address space and
2344 * remap the buffer in it.
2345 */
2346 down_write(&task->mm->mmap_sem);
2347
2348 /* find some free area in address space, must have mmap sem held */
2349 vma->vm_start = pfm_get_unmapped_area(NULL, 0, size, 0, MAP_PRIVATE|MAP_ANONYMOUS, 0);
2350 if (vma->vm_start == 0UL) {
2351 DPRINT(("Cannot find unmapped area for size %ld\n", size));
2352 up_write(&task->mm->mmap_sem);
2353 goto error;
2354 }
2355 vma->vm_end = vma->vm_start + size;
2356 vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
2357
2358 DPRINT(("aligned size=%ld, hdr=%p mapped @0x%lx\n", size, ctx->ctx_smpl_hdr, vma->vm_start));
2359
2360 /* can only be applied to current task, need to have the mm semaphore held when called */
2361 if (pfm_remap_buffer(vma, (unsigned long)smpl_buf, vma->vm_start, size)) {
2362 DPRINT(("Can't remap buffer\n"));
2363 up_write(&task->mm->mmap_sem);
2364 goto error;
2365 }
2366
2367 get_file(filp);
2368
2369 /*
2370 * now insert the vma in the vm list for the process, must be
2371 * done with mmap lock held
2372 */
2373 insert_vm_struct(mm, vma);
2374
2375 mm->total_vm += size >> PAGE_SHIFT;
2376 vm_stat_account(vma->vm_mm, vma->vm_flags, vma->vm_file,
2377 vma_pages(vma));
2378 up_write(&task->mm->mmap_sem);
2379
2380 /*
2381 * keep track of user level virtual address
2382 */
2383 ctx->ctx_smpl_vaddr = (void *)vma->vm_start;
2384 *(unsigned long *)user_vaddr = vma->vm_start;
2385
2386 return 0;
2387
2388 error:
2389 kmem_cache_free(vm_area_cachep, vma);
2390 error_kmem:
2391 pfm_rvfree(smpl_buf, size);
2392
2393 return -ENOMEM;
2394 }
2395
2396 /*
2397 * XXX: do something better here
2398 */
2399 static int
2400 pfm_bad_permissions(struct task_struct *task)
2401 {
2402 const struct cred *tcred;
2403 uid_t uid = current_uid();
2404 gid_t gid = current_gid();
2405 int ret;
2406
2407 rcu_read_lock();
2408 tcred = __task_cred(task);
2409
2410 /* inspired by ptrace_attach() */
2411 DPRINT(("cur: uid=%d gid=%d task: euid=%d suid=%d uid=%d egid=%d sgid=%d\n",
2412 uid,
2413 gid,
2414 tcred->euid,
2415 tcred->suid,
2416 tcred->uid,
2417 tcred->egid,
2418 tcred->sgid));
2419
2420 ret = ((uid != tcred->euid)
2421 || (uid != tcred->suid)
2422 || (uid != tcred->uid)
2423 || (gid != tcred->egid)
2424 || (gid != tcred->sgid)
2425 || (gid != tcred->gid)) && !capable(CAP_SYS_PTRACE);
2426
2427 rcu_read_unlock();
2428 return ret;
2429 }
2430
2431 static int
2432 pfarg_is_sane(struct task_struct *task, pfarg_context_t *pfx)
2433 {
2434 int ctx_flags;
2435
2436 /* valid signal */
2437
2438 ctx_flags = pfx->ctx_flags;
2439
2440 if (ctx_flags & PFM_FL_SYSTEM_WIDE) {
2441
2442 /*
2443 * cannot block in this mode
2444 */
2445 if (ctx_flags & PFM_FL_NOTIFY_BLOCK) {
2446 DPRINT(("cannot use blocking mode when in system wide monitoring\n"));
2447 return -EINVAL;
2448 }
2449 } else {
2450 }
2451 /* probably more to add here */
2452
2453 return 0;
2454 }
2455
2456 static int
2457 pfm_setup_buffer_fmt(struct task_struct *task, struct file *filp, pfm_context_t *ctx, unsigned int ctx_flags,
2458 unsigned int cpu, pfarg_context_t *arg)
2459 {
2460 pfm_buffer_fmt_t *fmt = NULL;
2461 unsigned long size = 0UL;
2462 void *uaddr = NULL;
2463 void *fmt_arg = NULL;
2464 int ret = 0;
2465 #define PFM_CTXARG_BUF_ARG(a) (pfm_buffer_fmt_t *)(a+1)
2466
2467 /* invoke and lock buffer format, if found */
2468 fmt = pfm_find_buffer_fmt(arg->ctx_smpl_buf_id);
2469 if (fmt == NULL) {
2470 DPRINT(("[%d] cannot find buffer format\n", task_pid_nr(task)));
2471 return -EINVAL;
2472 }
2473
2474 /*
2475 * buffer argument MUST be contiguous to pfarg_context_t
2476 */
2477 if (fmt->fmt_arg_size) fmt_arg = PFM_CTXARG_BUF_ARG(arg);
2478
2479 ret = pfm_buf_fmt_validate(fmt, task, ctx_flags, cpu, fmt_arg);
2480
2481 DPRINT(("[%d] after validate(0x%x,%d,%p)=%d\n", task_pid_nr(task), ctx_flags, cpu, fmt_arg, ret));
2482
2483 if (ret) goto error;
2484
2485 /* link buffer format and context */
2486 ctx->ctx_buf_fmt = fmt;
2487 ctx->ctx_fl_is_sampling = 1; /* assume record() is defined */
2488
2489 /*
2490 * check if buffer format wants to use perfmon buffer allocation/mapping service
2491 */
2492 ret = pfm_buf_fmt_getsize(fmt, task, ctx_flags, cpu, fmt_arg, &size);
2493 if (ret) goto error;
2494
2495 if (size) {
2496 /*
2497 * buffer is always remapped into the caller's address space
2498 */
2499 ret = pfm_smpl_buffer_alloc(current, filp, ctx, size, &uaddr);
2500 if (ret) goto error;
2501
2502 /* keep track of user address of buffer */
2503 arg->ctx_smpl_vaddr = uaddr;
2504 }
2505 ret = pfm_buf_fmt_init(fmt, task, ctx->ctx_smpl_hdr, ctx_flags, cpu, fmt_arg);
2506
2507 error:
2508 return ret;
2509 }
2510
2511 static void
2512 pfm_reset_pmu_state(pfm_context_t *ctx)
2513 {
2514 int i;
2515
2516 /*
2517 * install reset values for PMC.
2518 */
2519 for (i=1; PMC_IS_LAST(i) == 0; i++) {
2520 if (PMC_IS_IMPL(i) == 0) continue;
2521 ctx->ctx_pmcs[i] = PMC_DFL_VAL(i);
2522 DPRINT(("pmc[%d]=0x%lx\n", i, ctx->ctx_pmcs[i]));
2523 }
2524 /*
2525 * PMD registers are set to 0UL when the context in memset()
2526 */
2527
2528 /*
2529 * On context switched restore, we must restore ALL pmc and ALL pmd even
2530 * when they are not actively used by the task. In UP, the incoming process
2531 * may otherwise pick up left over PMC, PMD state from the previous process.
2532 * As opposed to PMD, stale PMC can cause harm to the incoming
2533 * process because they may change what is being measured.
2534 * Therefore, we must systematically reinstall the entire
2535 * PMC state. In SMP, the same thing is possible on the
2536 * same CPU but also on between 2 CPUs.
2537 *
2538 * The problem with PMD is information leaking especially
2539 * to user level when psr.sp=0
2540 *
2541 * There is unfortunately no easy way to avoid this problem
2542 * on either UP or SMP. This definitively slows down the
2543 * pfm_load_regs() function.
2544 */
2545
2546 /*
2547 * bitmask of all PMCs accessible to this context
2548 *
2549 * PMC0 is treated differently.
2550 */
2551 ctx->ctx_all_pmcs[0] = pmu_conf->impl_pmcs[0] & ~0x1;
2552
2553 /*
2554 * bitmask of all PMDs that are accessible to this context
2555 */
2556 ctx->ctx_all_pmds[0] = pmu_conf->impl_pmds[0];
2557
2558 DPRINT(("<%d> all_pmcs=0x%lx all_pmds=0x%lx\n", ctx->ctx_fd, ctx->ctx_all_pmcs[0],ctx->ctx_all_pmds[0]));
2559
2560 /*
2561 * useful in case of re-enable after disable
2562 */
2563 ctx->ctx_used_ibrs[0] = 0UL;
2564 ctx->ctx_used_dbrs[0] = 0UL;
2565 }
2566
2567 static int
2568 pfm_ctx_getsize(void *arg, size_t *sz)
2569 {
2570 pfarg_context_t *req = (pfarg_context_t *)arg;
2571 pfm_buffer_fmt_t *fmt;
2572
2573 *sz = 0;
2574
2575 if (!pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) return 0;
2576
2577 fmt = pfm_find_buffer_fmt(req->ctx_smpl_buf_id);
2578 if (fmt == NULL) {
2579 DPRINT(("cannot find buffer format\n"));
2580 return -EINVAL;
2581 }
2582 /* get just enough to copy in user parameters */
2583 *sz = fmt->fmt_arg_size;
2584 DPRINT(("arg_size=%lu\n", *sz));
2585
2586 return 0;
2587 }
2588
2589
2590
2591 /*
2592 * cannot attach if :
2593 * - kernel task
2594 * - task not owned by caller
2595 * - task incompatible with context mode
2596 */
2597 static int
2598 pfm_task_incompatible(pfm_context_t *ctx, struct task_struct *task)
2599 {
2600 /*
2601 * no kernel task or task not owner by caller
2602 */
2603 if (task->mm == NULL) {
2604 DPRINT(("task [%d] has not memory context (kernel thread)\n", task_pid_nr(task)));
2605 return -EPERM;
2606 }
2607 if (pfm_bad_permissions(task)) {
2608 DPRINT(("no permission to attach to [%d]\n", task_pid_nr(task)));
2609 return -EPERM;
2610 }
2611 /*
2612 * cannot block in self-monitoring mode
2613 */
2614 if (CTX_OVFL_NOBLOCK(ctx) == 0 && task == current) {
2615 DPRINT(("cannot load a blocking context on self for [%d]\n", task_pid_nr(task)));
2616 return -EINVAL;
2617 }
2618
2619 if (task->exit_state == EXIT_ZOMBIE) {
2620 DPRINT(("cannot attach to zombie task [%d]\n", task_pid_nr(task)));
2621 return -EBUSY;
2622 }
2623
2624 /*
2625 * always ok for self
2626 */
2627 if (task == current) return 0;
2628
2629 if (!task_is_stopped_or_traced(task)) {
2630 DPRINT(("cannot attach to non-stopped task [%d] state=%ld\n", task_pid_nr(task), task->state));
2631 return -EBUSY;
2632 }
2633 /*
2634 * make sure the task is off any CPU
2635 */
2636 wait_task_inactive(task, 0);
2637
2638 /* more to come... */
2639
2640 return 0;
2641 }
2642
2643 static int
2644 pfm_get_task(pfm_context_t *ctx, pid_t pid, struct task_struct **task)
2645 {
2646 struct task_struct *p = current;
2647 int ret;
2648
2649 /* XXX: need to add more checks here */
2650 if (pid < 2) return -EPERM;
2651
2652 if (pid != task_pid_vnr(current)) {
2653
2654 read_lock(&tasklist_lock);
2655
2656 p = find_task_by_vpid(pid);
2657
2658 /* make sure task cannot go away while we operate on it */
2659 if (p) get_task_struct(p);
2660
2661 read_unlock(&tasklist_lock);
2662
2663 if (p == NULL) return -ESRCH;
2664 }
2665
2666 ret = pfm_task_incompatible(ctx, p);
2667 if (ret == 0) {
2668 *task = p;
2669 } else if (p != current) {
2670 pfm_put_task(p);
2671 }
2672 return ret;
2673 }
2674
2675
2676
2677 static int
2678 pfm_context_create(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
2679 {
2680 pfarg_context_t *req = (pfarg_context_t *)arg;
2681 struct file *filp;
2682 struct path path;
2683 int ctx_flags;
2684 int fd;
2685 int ret;
2686
2687 /* let's check the arguments first */
2688 ret = pfarg_is_sane(current, req);
2689 if (ret < 0)
2690 return ret;
2691
2692 ctx_flags = req->ctx_flags;
2693
2694 ret = -ENOMEM;
2695
2696 fd = get_unused_fd();
2697 if (fd < 0)
2698 return fd;
2699
2700 ctx = pfm_context_alloc(ctx_flags);
2701 if (!ctx)
2702 goto error;
2703
2704 filp = pfm_alloc_file(ctx);
2705 if (IS_ERR(filp)) {
2706 ret = PTR_ERR(filp);
2707 goto error_file;
2708 }
2709
2710 req->ctx_fd = ctx->ctx_fd = fd;
2711
2712 /*
2713 * does the user want to sample?
2714 */
2715 if (pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) {
2716 ret = pfm_setup_buffer_fmt(current, filp, ctx, ctx_flags, 0, req);
2717 if (ret)
2718 goto buffer_error;
2719 }
2720
2721 DPRINT(("ctx=%p flags=0x%x system=%d notify_block=%d excl_idle=%d no_msg=%d ctx_fd=%d \n",
2722 ctx,
2723 ctx_flags,
2724 ctx->ctx_fl_system,
2725 ctx->ctx_fl_block,
2726 ctx->ctx_fl_excl_idle,
2727 ctx->ctx_fl_no_msg,
2728 ctx->ctx_fd));
2729
2730 /*
2731 * initialize soft PMU state
2732 */
2733 pfm_reset_pmu_state(ctx);
2734
2735 fd_install(fd, filp);
2736
2737 return 0;
2738
2739 buffer_error:
2740 path = filp->f_path;
2741 put_filp(filp);
2742 path_put(&path);
2743
2744 if (ctx->ctx_buf_fmt) {
2745 pfm_buf_fmt_exit(ctx->ctx_buf_fmt, current, NULL, regs);
2746 }
2747 error_file:
2748 pfm_context_free(ctx);
2749
2750 error:
2751 put_unused_fd(fd);
2752 return ret;
2753 }
2754
2755 static inline unsigned long
2756 pfm_new_counter_value (pfm_counter_t *reg, int is_long_reset)
2757 {
2758 unsigned long val = is_long_reset ? reg->long_reset : reg->short_reset;
2759 unsigned long new_seed, old_seed = reg->seed, mask = reg->mask;
2760 extern unsigned long carta_random32 (unsigned long seed);
2761
2762 if (reg->flags & PFM_REGFL_RANDOM) {
2763 new_seed = carta_random32(old_seed);
2764 val -= (old_seed & mask); /* counter values are negative numbers! */
2765 if ((mask >> 32) != 0)
2766 /* construct a full 64-bit random value: */
2767 new_seed |= carta_random32(old_seed >> 32) << 32;
2768 reg->seed = new_seed;
2769 }
2770 reg->lval = val;
2771 return val;
2772 }
2773
2774 static void
2775 pfm_reset_regs_masked(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset)
2776 {
2777 unsigned long mask = ovfl_regs[0];
2778 unsigned long reset_others = 0UL;
2779 unsigned long val;
2780 int i;
2781
2782 /*
2783 * now restore reset value on sampling overflowed counters
2784 */
2785 mask >>= PMU_FIRST_COUNTER;
2786 for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) {
2787
2788 if ((mask & 0x1UL) == 0UL) continue;
2789
2790 ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset);
2791 reset_others |= ctx->ctx_pmds[i].reset_pmds[0];
2792
2793 DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val));
2794 }
2795
2796 /*
2797 * Now take care of resetting the other registers
2798 */
2799 for(i = 0; reset_others; i++, reset_others >>= 1) {
2800
2801 if ((reset_others & 0x1) == 0) continue;
2802
2803 ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset);
2804
2805 DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n",
2806 is_long_reset ? "long" : "short", i, val));
2807 }
2808 }
2809
2810 static void
2811 pfm_reset_regs(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset)
2812 {
2813 unsigned long mask = ovfl_regs[0];
2814 unsigned long reset_others = 0UL;
2815 unsigned long val;
2816 int i;
2817
2818 DPRINT_ovfl(("ovfl_regs=0x%lx is_long_reset=%d\n", ovfl_regs[0], is_long_reset));
2819
2820 if (ctx->ctx_state == PFM_CTX_MASKED) {
2821 pfm_reset_regs_masked(ctx, ovfl_regs, is_long_reset);
2822 return;
2823 }
2824
2825 /*
2826 * now restore reset value on sampling overflowed counters
2827 */
2828 mask >>= PMU_FIRST_COUNTER;
2829 for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) {
2830
2831 if ((mask & 0x1UL) == 0UL) continue;
2832
2833 val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset);
2834 reset_others |= ctx->ctx_pmds[i].reset_pmds[0];
2835
2836 DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val));
2837
2838 pfm_write_soft_counter(ctx, i, val);
2839 }
2840
2841 /*
2842 * Now take care of resetting the other registers
2843 */
2844 for(i = 0; reset_others; i++, reset_others >>= 1) {
2845
2846 if ((reset_others & 0x1) == 0) continue;
2847
2848 val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset);
2849
2850 if (PMD_IS_COUNTING(i)) {
2851 pfm_write_soft_counter(ctx, i, val);
2852 } else {
2853 ia64_set_pmd(i, val);
2854 }
2855 DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n",
2856 is_long_reset ? "long" : "short", i, val));
2857 }
2858 ia64_srlz_d();
2859 }
2860
2861 static int
2862 pfm_write_pmcs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
2863 {
2864 struct task_struct *task;
2865 pfarg_reg_t *req = (pfarg_reg_t *)arg;
2866 unsigned long value, pmc_pm;
2867 unsigned long smpl_pmds, reset_pmds, impl_pmds;
2868 unsigned int cnum, reg_flags, flags, pmc_type;
2869 int i, can_access_pmu = 0, is_loaded, is_system, expert_mode;
2870 int is_monitor, is_counting, state;
2871 int ret = -EINVAL;
2872 pfm_reg_check_t wr_func;
2873 #define PFM_CHECK_PMC_PM(x, y, z) ((x)->ctx_fl_system ^ PMC_PM(y, z))
2874
2875 state = ctx->ctx_state;
2876 is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
2877 is_system = ctx->ctx_fl_system;
2878 task = ctx->ctx_task;
2879 impl_pmds = pmu_conf->impl_pmds[0];
2880
2881 if (state == PFM_CTX_ZOMBIE) return -EINVAL;
2882
2883 if (is_loaded) {
2884 /*
2885 * In system wide and when the context is loaded, access can only happen
2886 * when the caller is running on the CPU being monitored by the session.
2887 * It does not have to be the owner (ctx_task) of the context per se.
2888 */
2889 if (is_system && ctx->ctx_cpu != smp_processor_id()) {
2890 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
2891 return -EBUSY;
2892 }
2893 can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
2894 }
2895 expert_mode = pfm_sysctl.expert_mode;
2896
2897 for (i = 0; i < count; i++, req++) {
2898
2899 cnum = req->reg_num;
2900 reg_flags = req->reg_flags;
2901 value = req->reg_value;
2902 smpl_pmds = req->reg_smpl_pmds[0];
2903 reset_pmds = req->reg_reset_pmds[0];
2904 flags = 0;
2905
2906
2907 if (cnum >= PMU_MAX_PMCS) {
2908 DPRINT(("pmc%u is invalid\n", cnum));
2909 goto error;
2910 }
2911
2912 pmc_type = pmu_conf->pmc_desc[cnum].type;
2913 pmc_pm = (value >> pmu_conf->pmc_desc[cnum].pm_pos) & 0x1;
2914 is_counting = (pmc_type & PFM_REG_COUNTING) == PFM_REG_COUNTING ? 1 : 0;
2915 is_monitor = (pmc_type & PFM_REG_MONITOR) == PFM_REG_MONITOR ? 1 : 0;
2916
2917 /*
2918 * we reject all non implemented PMC as well
2919 * as attempts to modify PMC[0-3] which are used
2920 * as status registers by the PMU
2921 */
2922 if ((pmc_type & PFM_REG_IMPL) == 0 || (pmc_type & PFM_REG_CONTROL) == PFM_REG_CONTROL) {
2923 DPRINT(("pmc%u is unimplemented or no-access pmc_type=%x\n", cnum, pmc_type));
2924 goto error;
2925 }
2926 wr_func = pmu_conf->pmc_desc[cnum].write_check;
2927 /*
2928 * If the PMC is a monitor, then if the value is not the default:
2929 * - system-wide session: PMCx.pm=1 (privileged monitor)
2930 * - per-task : PMCx.pm=0 (user monitor)
2931 */
2932 if (is_monitor && value != PMC_DFL_VAL(cnum) && is_system ^ pmc_pm) {
2933 DPRINT(("pmc%u pmc_pm=%lu is_system=%d\n",
2934 cnum,
2935 pmc_pm,
2936 is_system));
2937 goto error;
2938 }
2939
2940 if (is_counting) {
2941 /*
2942 * enforce generation of overflow interrupt. Necessary on all
2943 * CPUs.
2944 */
2945 value |= 1 << PMU_PMC_OI;
2946
2947 if (reg_flags & PFM_REGFL_OVFL_NOTIFY) {
2948 flags |= PFM_REGFL_OVFL_NOTIFY;
2949 }
2950
2951 if (reg_flags & PFM_REGFL_RANDOM) flags |= PFM_REGFL_RANDOM;
2952
2953 /* verify validity of smpl_pmds */
2954 if ((smpl_pmds & impl_pmds) != smpl_pmds) {
2955 DPRINT(("invalid smpl_pmds 0x%lx for pmc%u\n", smpl_pmds, cnum));
2956 goto error;
2957 }
2958
2959 /* verify validity of reset_pmds */
2960 if ((reset_pmds & impl_pmds) != reset_pmds) {
2961 DPRINT(("invalid reset_pmds 0x%lx for pmc%u\n", reset_pmds, cnum));
2962 goto error;
2963 }
2964 } else {
2965 if (reg_flags & (PFM_REGFL_OVFL_NOTIFY|PFM_REGFL_RANDOM)) {
2966 DPRINT(("cannot set ovfl_notify or random on pmc%u\n", cnum));
2967 goto error;
2968 }
2969 /* eventid on non-counting monitors are ignored */
2970 }
2971
2972 /*
2973 * execute write checker, if any
2974 */
2975 if (likely(expert_mode == 0 && wr_func)) {
2976 ret = (*wr_func)(task, ctx, cnum, &value, regs);
2977 if (ret) goto error;
2978 ret = -EINVAL;
2979 }
2980
2981 /*
2982 * no error on this register
2983 */
2984 PFM_REG_RETFLAG_SET(req->reg_flags, 0);
2985
2986 /*
2987 * Now we commit the changes to the software state
2988 */
2989
2990 /*
2991 * update overflow information
2992 */
2993 if (is_counting) {
2994 /*
2995 * full flag update each time a register is programmed
2996 */
2997 ctx->ctx_pmds[cnum].flags = flags;
2998
2999 ctx->ctx_pmds[cnum].reset_pmds[0] = reset_pmds;
3000 ctx->ctx_pmds[cnum].smpl_pmds[0] = smpl_pmds;
3001 ctx->ctx_pmds[cnum].eventid = req->reg_smpl_eventid;
3002
3003 /*
3004 * Mark all PMDS to be accessed as used.
3005 *
3006 * We do not keep track of PMC because we have to
3007 * systematically restore ALL of them.
3008 *
3009 * We do not update the used_monitors mask, because
3010 * if we have not programmed them, then will be in
3011 * a quiescent state, therefore we will not need to
3012 * mask/restore then when context is MASKED.
3013 */
3014 CTX_USED_PMD(ctx, reset_pmds);
3015 CTX_USED_PMD(ctx, smpl_pmds);
3016 /*
3017 * make sure we do not try to reset on
3018 * restart because we have established new values
3019 */
3020 if (state == PFM_CTX_MASKED) ctx->ctx_ovfl_regs[0] &= ~1UL << cnum;
3021 }
3022 /*
3023 * Needed in case the user does not initialize the equivalent
3024 * PMD. Clearing is done indirectly via pfm_reset_pmu_state() so there is no
3025 * possible leak here.
3026 */
3027 CTX_USED_PMD(ctx, pmu_conf->pmc_desc[cnum].dep_pmd[0]);
3028
3029 /*
3030 * keep track of the monitor PMC that we are using.
3031 * we save the value of the pmc in ctx_pmcs[] and if
3032 * the monitoring is not stopped for the context we also
3033 * place it in the saved state area so that it will be
3034 * picked up later by the context switch code.
3035 *
3036 * The value in ctx_pmcs[] can only be changed in pfm_write_pmcs().
3037 *
3038 * The value in th_pmcs[] may be modified on overflow, i.e., when
3039 * monitoring needs to be stopped.
3040 */
3041 if (is_monitor) CTX_USED_MONITOR(ctx, 1UL << cnum);
3042
3043 /*
3044 * update context state
3045 */
3046 ctx->ctx_pmcs[cnum] = value;
3047
3048 if (is_loaded) {
3049 /*
3050 * write thread state
3051 */
3052 if (is_system == 0) ctx->th_pmcs[cnum] = value;
3053
3054 /*
3055 * write hardware register if we can
3056 */
3057 if (can_access_pmu) {
3058 ia64_set_pmc(cnum, value);
3059 }
3060 #ifdef CONFIG_SMP
3061 else {
3062 /*
3063 * per-task SMP only here
3064 *
3065 * we are guaranteed that the task is not running on the other CPU,
3066 * we indicate that this PMD will need to be reloaded if the task
3067 * is rescheduled on the CPU it ran last on.
3068 */
3069 ctx->ctx_reload_pmcs[0] |= 1UL << cnum;
3070 }
3071 #endif
3072 }
3073
3074 DPRINT(("pmc[%u]=0x%lx ld=%d apmu=%d flags=0x%x all_pmcs=0x%lx used_pmds=0x%lx eventid=%ld smpl_pmds=0x%lx reset_pmds=0x%lx reloads_pmcs=0x%lx used_monitors=0x%lx ovfl_regs=0x%lx\n",
3075 cnum,
3076 value,
3077 is_loaded,
3078 can_access_pmu,
3079 flags,
3080 ctx->ctx_all_pmcs[0],
3081 ctx->ctx_used_pmds[0],
3082 ctx->ctx_pmds[cnum].eventid,
3083 smpl_pmds,
3084 reset_pmds,
3085 ctx->ctx_reload_pmcs[0],
3086 ctx->ctx_used_monitors[0],
3087 ctx->ctx_ovfl_regs[0]));
3088 }
3089
3090 /*
3091 * make sure the changes are visible
3092 */
3093 if (can_access_pmu) ia64_srlz_d();
3094
3095 return 0;
3096 error:
3097 PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
3098 return ret;
3099 }
3100
3101 static int
3102 pfm_write_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3103 {
3104 struct task_struct *task;
3105 pfarg_reg_t *req = (pfarg_reg_t *)arg;
3106 unsigned long value, hw_value, ovfl_mask;
3107 unsigned int cnum;
3108 int i, can_access_pmu = 0, state;
3109 int is_counting, is_loaded, is_system, expert_mode;
3110 int ret = -EINVAL;
3111 pfm_reg_check_t wr_func;
3112
3113
3114 state = ctx->ctx_state;
3115 is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
3116 is_system = ctx->ctx_fl_system;
3117 ovfl_mask = pmu_conf->ovfl_val;
3118 task = ctx->ctx_task;
3119
3120 if (unlikely(state == PFM_CTX_ZOMBIE)) return -EINVAL;
3121
3122 /*
3123 * on both UP and SMP, we can only write to the PMC when the task is
3124 * the owner of the local PMU.
3125 */
3126 if (likely(is_loaded)) {
3127 /*
3128 * In system wide and when the context is loaded, access can only happen
3129 * when the caller is running on the CPU being monitored by the session.
3130 * It does not have to be the owner (ctx_task) of the context per se.
3131 */
3132 if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) {
3133 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
3134 return -EBUSY;
3135 }
3136 can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
3137 }
3138 expert_mode = pfm_sysctl.expert_mode;
3139
3140 for (i = 0; i < count; i++, req++) {
3141
3142 cnum = req->reg_num;
3143 value = req->reg_value;
3144
3145 if (!PMD_IS_IMPL(cnum)) {
3146 DPRINT(("pmd[%u] is unimplemented or invalid\n", cnum));
3147 goto abort_mission;
3148 }
3149 is_counting = PMD_IS_COUNTING(cnum);
3150 wr_func = pmu_conf->pmd_desc[cnum].write_check;
3151
3152 /*
3153 * execute write checker, if any
3154 */
3155 if (unlikely(expert_mode == 0 && wr_func)) {
3156 unsigned long v = value;
3157
3158 ret = (*wr_func)(task, ctx, cnum, &v, regs);
3159 if (ret) goto abort_mission;
3160
3161 value = v;
3162 ret = -EINVAL;
3163 }
3164
3165 /*
3166 * no error on this register
3167 */
3168 PFM_REG_RETFLAG_SET(req->reg_flags, 0);
3169
3170 /*
3171 * now commit changes to software state
3172 */
3173 hw_value = value;
3174
3175 /*
3176 * update virtualized (64bits) counter
3177 */
3178 if (is_counting) {
3179 /*
3180 * write context state
3181 */
3182 ctx->ctx_pmds[cnum].lval = value;
3183
3184 /*
3185 * when context is load we use the split value
3186 */
3187 if (is_loaded) {
3188 hw_value = value & ovfl_mask;
3189 value = value & ~ovfl_mask;
3190 }
3191 }
3192 /*
3193 * update reset values (not just for counters)
3194 */
3195 ctx->ctx_pmds[cnum].long_reset = req->reg_long_reset;
3196 ctx->ctx_pmds[cnum].short_reset = req->reg_short_reset;
3197
3198 /*
3199 * update randomization parameters (not just for counters)
3200 */
3201 ctx->ctx_pmds[cnum].seed = req->reg_random_seed;
3202 ctx->ctx_pmds[cnum].mask = req->reg_random_mask;
3203
3204 /*
3205 * update context value
3206 */
3207 ctx->ctx_pmds[cnum].val = value;
3208
3209 /*
3210 * Keep track of what we use
3211 *
3212 * We do not keep track of PMC because we have to
3213 * systematically restore ALL of them.
3214 */
3215 CTX_USED_PMD(ctx, PMD_PMD_DEP(cnum));
3216
3217 /*
3218 * mark this PMD register used as well
3219 */
3220 CTX_USED_PMD(ctx, RDEP(cnum));
3221
3222 /*
3223 * make sure we do not try to reset on
3224 * restart because we have established new values
3225 */
3226 if (is_counting && state == PFM_CTX_MASKED) {
3227 ctx->ctx_ovfl_regs[0] &= ~1UL << cnum;
3228 }
3229
3230 if (is_loaded) {
3231 /*
3232 * write thread state
3233 */
3234 if (is_system == 0) ctx->th_pmds[cnum] = hw_value;
3235
3236 /*
3237 * write hardware register if we can
3238 */
3239 if (can_access_pmu) {
3240 ia64_set_pmd(cnum, hw_value);
3241 } else {
3242 #ifdef CONFIG_SMP
3243 /*
3244 * we are guaranteed that the task is not running on the other CPU,
3245 * we indicate that this PMD will need to be reloaded if the task
3246 * is rescheduled on the CPU it ran last on.
3247 */
3248 ctx->ctx_reload_pmds[0] |= 1UL << cnum;
3249 #endif
3250 }
3251 }
3252
3253 DPRINT(("pmd[%u]=0x%lx ld=%d apmu=%d, hw_value=0x%lx ctx_pmd=0x%lx short_reset=0x%lx "
3254 "long_reset=0x%lx notify=%c seed=0x%lx mask=0x%lx used_pmds=0x%lx reset_pmds=0x%lx reload_pmds=0x%lx all_pmds=0x%lx ovfl_regs=0x%lx\n",
3255 cnum,
3256 value,
3257 is_loaded,
3258 can_access_pmu,
3259 hw_value,
3260 ctx->ctx_pmds[cnum].val,
3261 ctx->ctx_pmds[cnum].short_reset,
3262 ctx->ctx_pmds[cnum].long_reset,
3263 PMC_OVFL_NOTIFY(ctx, cnum) ? 'Y':'N',
3264 ctx->ctx_pmds[cnum].seed,
3265 ctx->ctx_pmds[cnum].mask,
3266 ctx->ctx_used_pmds[0],
3267 ctx->ctx_pmds[cnum].reset_pmds[0],
3268 ctx->ctx_reload_pmds[0],
3269 ctx->ctx_all_pmds[0],
3270 ctx->ctx_ovfl_regs[0]));
3271 }
3272
3273 /*
3274 * make changes visible
3275 */
3276 if (can_access_pmu) ia64_srlz_d();
3277
3278 return 0;
3279
3280 abort_mission:
3281 /*
3282 * for now, we have only one possibility for error
3283 */
3284 PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
3285 return ret;
3286 }
3287
3288 /*
3289 * By the way of PROTECT_CONTEXT(), interrupts are masked while we are in this function.
3290 * Therefore we know, we do not have to worry about the PMU overflow interrupt. If an
3291 * interrupt is delivered during the call, it will be kept pending until we leave, making
3292 * it appears as if it had been generated at the UNPROTECT_CONTEXT(). At least we are
3293 * guaranteed to return consistent data to the user, it may simply be old. It is not
3294 * trivial to treat the overflow while inside the call because you may end up in
3295 * some module sampling buffer code causing deadlocks.
3296 */
3297 static int
3298 pfm_read_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3299 {
3300 struct task_struct *task;
3301 unsigned long val = 0UL, lval, ovfl_mask, sval;
3302 pfarg_reg_t *req = (pfarg_reg_t *)arg;
3303 unsigned int cnum, reg_flags = 0;
3304 int i, can_access_pmu = 0, state;
3305 int is_loaded, is_system, is_counting, expert_mode;
3306 int ret = -EINVAL;
3307 pfm_reg_check_t rd_func;
3308
3309 /*
3310 * access is possible when loaded only for
3311 * self-monitoring tasks or in UP mode
3312 */
3313
3314 state = ctx->ctx_state;
3315 is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
3316 is_system = ctx->ctx_fl_system;
3317 ovfl_mask = pmu_conf->ovfl_val;
3318 task = ctx->ctx_task;
3319
3320 if (state == PFM_CTX_ZOMBIE) return -EINVAL;
3321
3322 if (likely(is_loaded)) {
3323 /*
3324 * In system wide and when the context is loaded, access can only happen
3325 * when the caller is running on the CPU being monitored by the session.
3326 * It does not have to be the owner (ctx_task) of the context per se.
3327 */
3328 if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) {
3329 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
3330 return -EBUSY;
3331 }
3332 /*
3333 * this can be true when not self-monitoring only in UP
3334 */
3335 can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
3336
3337 if (can_access_pmu) ia64_srlz_d();
3338 }
3339 expert_mode = pfm_sysctl.expert_mode;
3340
3341 DPRINT(("ld=%d apmu=%d ctx_state=%d\n",
3342 is_loaded,
3343 can_access_pmu,
3344 state));
3345
3346 /*
3347 * on both UP and SMP, we can only read the PMD from the hardware register when
3348 * the task is the owner of the local PMU.
3349 */
3350
3351 for (i = 0; i < count; i++, req++) {
3352
3353 cnum = req->reg_num;
3354 reg_flags = req->reg_flags;
3355
3356 if (unlikely(!PMD_IS_IMPL(cnum))) goto error;
3357 /*
3358 * we can only read the register that we use. That includes
3359 * the one we explicitly initialize AND the one we want included
3360 * in the sampling buffer (smpl_regs).
3361 *
3362 * Having this restriction allows optimization in the ctxsw routine
3363 * without compromising security (leaks)
3364 */
3365 if (unlikely(!CTX_IS_USED_PMD(ctx, cnum))) goto error;
3366
3367 sval = ctx->ctx_pmds[cnum].val;
3368 lval = ctx->ctx_pmds[cnum].lval;
3369 is_counting = PMD_IS_COUNTING(cnum);
3370
3371 /*
3372 * If the task is not the current one, then we check if the
3373 * PMU state is still in the local live register due to lazy ctxsw.
3374 * If true, then we read directly from the registers.
3375 */
3376 if (can_access_pmu){
3377 val = ia64_get_pmd(cnum);
3378 } else {
3379 /*
3380 * context has been saved
3381 * if context is zombie, then task does not exist anymore.
3382 * In this case, we use the full value saved in the context (pfm_flush_regs()).
3383 */
3384 val = is_loaded ? ctx->th_pmds[cnum] : 0UL;
3385 }
3386 rd_func = pmu_conf->pmd_desc[cnum].read_check;
3387
3388 if (is_counting) {
3389 /*
3390 * XXX: need to check for overflow when loaded
3391 */
3392 val &= ovfl_mask;
3393 val += sval;
3394 }
3395
3396 /*
3397 * execute read checker, if any
3398 */
3399 if (unlikely(expert_mode == 0 && rd_func)) {
3400 unsigned long v = val;
3401 ret = (*rd_func)(ctx->ctx_task, ctx, cnum, &v, regs);
3402 if (ret) goto error;
3403 val = v;
3404 ret = -EINVAL;
3405 }
3406
3407 PFM_REG_RETFLAG_SET(reg_flags, 0);
3408
3409 DPRINT(("pmd[%u]=0x%lx\n", cnum, val));
3410
3411 /*
3412 * update register return value, abort all if problem during copy.
3413 * we only modify the reg_flags field. no check mode is fine because
3414 * access has been verified upfront in sys_perfmonctl().
3415 */
3416 req->reg_value = val;
3417 req->reg_flags = reg_flags;
3418 req->reg_last_reset_val = lval;
3419 }
3420
3421 return 0;
3422
3423 error:
3424 PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
3425 return ret;
3426 }
3427
3428 int
3429 pfm_mod_write_pmcs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
3430 {
3431 pfm_context_t *ctx;
3432
3433 if (req == NULL) return -EINVAL;
3434
3435 ctx = GET_PMU_CTX();
3436
3437 if (ctx == NULL) return -EINVAL;
3438
3439 /*
3440 * for now limit to current task, which is enough when calling
3441 * from overflow handler
3442 */
3443 if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
3444
3445 return pfm_write_pmcs(ctx, req, nreq, regs);
3446 }
3447 EXPORT_SYMBOL(pfm_mod_write_pmcs);
3448
3449 int
3450 pfm_mod_read_pmds(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
3451 {
3452 pfm_context_t *ctx;
3453
3454 if (req == NULL) return -EINVAL;
3455
3456 ctx = GET_PMU_CTX();
3457
3458 if (ctx == NULL) return -EINVAL;
3459
3460 /*
3461 * for now limit to current task, which is enough when calling
3462 * from overflow handler
3463 */
3464 if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
3465
3466 return pfm_read_pmds(ctx, req, nreq, regs);
3467 }
3468 EXPORT_SYMBOL(pfm_mod_read_pmds);
3469
3470 /*
3471 * Only call this function when a process it trying to
3472 * write the debug registers (reading is always allowed)
3473 */
3474 int
3475 pfm_use_debug_registers(struct task_struct *task)
3476 {
3477 pfm_context_t *ctx = task->thread.pfm_context;
3478 unsigned long flags;
3479 int ret = 0;
3480
3481 if (pmu_conf->use_rr_dbregs == 0) return 0;
3482
3483 DPRINT(("called for [%d]\n", task_pid_nr(task)));
3484
3485 /*
3486 * do it only once
3487 */
3488 if (task->thread.flags & IA64_THREAD_DBG_VALID) return 0;
3489
3490 /*
3491 * Even on SMP, we do not need to use an atomic here because
3492 * the only way in is via ptrace() and this is possible only when the
3493 * process is stopped. Even in the case where the ctxsw out is not totally
3494 * completed by the time we come here, there is no way the 'stopped' process
3495 * could be in the middle of fiddling with the pfm_write_ibr_dbr() routine.
3496 * So this is always safe.
3497 */
3498 if (ctx && ctx->ctx_fl_using_dbreg == 1) return -1;
3499
3500 LOCK_PFS(flags);
3501
3502 /*
3503 * We cannot allow setting breakpoints when system wide monitoring
3504 * sessions are using the debug registers.
3505 */
3506 if (pfm_sessions.pfs_sys_use_dbregs> 0)
3507 ret = -1;
3508 else
3509 pfm_sessions.pfs_ptrace_use_dbregs++;
3510
3511 DPRINT(("ptrace_use_dbregs=%u sys_use_dbregs=%u by [%d] ret = %d\n",
3512 pfm_sessions.pfs_ptrace_use_dbregs,
3513 pfm_sessions.pfs_sys_use_dbregs,
3514 task_pid_nr(task), ret));
3515
3516 UNLOCK_PFS(flags);
3517
3518 return ret;
3519 }
3520
3521 /*
3522 * This function is called for every task that exits with the
3523 * IA64_THREAD_DBG_VALID set. This indicates a task which was
3524 * able to use the debug registers for debugging purposes via
3525 * ptrace(). Therefore we know it was not using them for
3526 * perfmormance monitoring, so we only decrement the number
3527 * of "ptraced" debug register users to keep the count up to date
3528 */
3529 int
3530 pfm_release_debug_registers(struct task_struct *task)
3531 {
3532 unsigned long flags;
3533 int ret;
3534
3535 if (pmu_conf->use_rr_dbregs == 0) return 0;
3536
3537 LOCK_PFS(flags);
3538 if (pfm_sessions.pfs_ptrace_use_dbregs == 0) {
3539 printk(KERN_ERR "perfmon: invalid release for [%d] ptrace_use_dbregs=0\n", task_pid_nr(task));
3540 ret = -1;
3541 } else {
3542 pfm_sessions.pfs_ptrace_use_dbregs--;
3543 ret = 0;
3544 }
3545 UNLOCK_PFS(flags);
3546
3547 return ret;
3548 }
3549
3550 static int
3551 pfm_restart(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3552 {
3553 struct task_struct *task;
3554 pfm_buffer_fmt_t *fmt;
3555 pfm_ovfl_ctrl_t rst_ctrl;
3556 int state, is_system;
3557 int ret = 0;
3558
3559 state = ctx->ctx_state;
3560 fmt = ctx->ctx_buf_fmt;
3561 is_system = ctx->ctx_fl_system;
3562 task = PFM_CTX_TASK(ctx);
3563
3564 switch(state) {
3565 case PFM_CTX_MASKED:
3566 break;
3567 case PFM_CTX_LOADED:
3568 if (CTX_HAS_SMPL(ctx) && fmt->fmt_restart_active) break;
3569 /* fall through */
3570 case PFM_CTX_UNLOADED:
3571 case PFM_CTX_ZOMBIE:
3572 DPRINT(("invalid state=%d\n", state));
3573 return -EBUSY;
3574 default:
3575 DPRINT(("state=%d, cannot operate (no active_restart handler)\n", state));
3576 return -EINVAL;
3577 }
3578
3579 /*
3580 * In system wide and when the context is loaded, access can only happen
3581 * when the caller is running on the CPU being monitored by the session.
3582 * It does not have to be the owner (ctx_task) of the context per se.
3583 */
3584 if (is_system && ctx->ctx_cpu != smp_processor_id()) {
3585 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
3586 return -EBUSY;
3587 }
3588
3589 /* sanity check */
3590 if (unlikely(task == NULL)) {
3591 printk(KERN_ERR "perfmon: [%d] pfm_restart no task\n", task_pid_nr(current));
3592 return -EINVAL;
3593 }
3594
3595 if (task == current || is_system) {
3596
3597 fmt = ctx->ctx_buf_fmt;
3598
3599 DPRINT(("restarting self %d ovfl=0x%lx\n",
3600 task_pid_nr(task),
3601 ctx->ctx_ovfl_regs[0]));
3602
3603 if (CTX_HAS_SMPL(ctx)) {
3604
3605 prefetch(ctx->ctx_smpl_hdr);
3606
3607 rst_ctrl.bits.mask_monitoring = 0;
3608 rst_ctrl.bits.reset_ovfl_pmds = 0;
3609
3610 if (state == PFM_CTX_LOADED)
3611 ret = pfm_buf_fmt_restart_active(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
3612 else
3613 ret = pfm_buf_fmt_restart(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
3614 } else {
3615 rst_ctrl.bits.mask_monitoring = 0;
3616 rst_ctrl.bits.reset_ovfl_pmds = 1;
3617 }
3618
3619 if (ret == 0) {
3620 if (rst_ctrl.bits.reset_ovfl_pmds)
3621 pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET);
3622
3623 if (rst_ctrl.bits.mask_monitoring == 0) {
3624 DPRINT(("resuming monitoring for [%d]\n", task_pid_nr(task)));
3625
3626 if (state == PFM_CTX_MASKED) pfm_restore_monitoring(task);
3627 } else {
3628 DPRINT(("keeping monitoring stopped for [%d]\n", task_pid_nr(task)));
3629
3630 // cannot use pfm_stop_monitoring(task, regs);
3631 }
3632 }
3633 /*
3634 * clear overflowed PMD mask to remove any stale information
3635 */
3636 ctx->ctx_ovfl_regs[0] = 0UL;
3637
3638 /*
3639 * back to LOADED state
3640 */
3641 ctx->ctx_state = PFM_CTX_LOADED;
3642
3643 /*
3644 * XXX: not really useful for self monitoring
3645 */
3646 ctx->ctx_fl_can_restart = 0;
3647
3648 return 0;
3649 }
3650
3651 /*
3652 * restart another task
3653 */
3654
3655 /*
3656 * When PFM_CTX_MASKED, we cannot issue a restart before the previous
3657 * one is seen by the task.
3658 */
3659 if (state == PFM_CTX_MASKED) {
3660 if (ctx->ctx_fl_can_restart == 0) return -EINVAL;
3661 /*
3662 * will prevent subsequent restart before this one is
3663 * seen by other task
3664 */
3665 ctx->ctx_fl_can_restart = 0;
3666 }
3667
3668 /*
3669 * if blocking, then post the semaphore is PFM_CTX_MASKED, i.e.
3670 * the task is blocked or on its way to block. That's the normal
3671 * restart path. If the monitoring is not masked, then the task
3672 * can be actively monitoring and we cannot directly intervene.
3673 * Therefore we use the trap mechanism to catch the task and
3674 * force it to reset the buffer/reset PMDs.
3675 *
3676 * if non-blocking, then we ensure that the task will go into
3677 * pfm_handle_work() before returning to user mode.
3678 *
3679 * We cannot explicitly reset another task, it MUST always
3680 * be done by the task itself. This works for system wide because
3681 * the tool that is controlling the session is logically doing
3682 * "self-monitoring".
3683 */
3684 if (CTX_OVFL_NOBLOCK(ctx) == 0 && state == PFM_CTX_MASKED) {
3685 DPRINT(("unblocking [%d] \n", task_pid_nr(task)));
3686 complete(&ctx->ctx_restart_done);
3687 } else {
3688 DPRINT(("[%d] armed exit trap\n", task_pid_nr(task)));
3689
3690 ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_RESET;
3691
3692 PFM_SET_WORK_PENDING(task, 1);
3693
3694 set_notify_resume(task);
3695
3696 /*
3697 * XXX: send reschedule if task runs on another CPU
3698 */
3699 }
3700 return 0;
3701 }
3702
3703 static int
3704 pfm_debug(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3705 {
3706 unsigned int m = *(unsigned int *)arg;
3707
3708 pfm_sysctl.debug = m == 0 ? 0 : 1;
3709
3710 printk(KERN_INFO "perfmon debugging %s (timing reset)\n", pfm_sysctl.debug ? "on" : "off");
3711
3712 if (m == 0) {
3713 memset(pfm_stats, 0, sizeof(pfm_stats));
3714 for(m=0; m < NR_CPUS; m++) pfm_stats[m].pfm_ovfl_intr_cycles_min = ~0UL;
3715 }
3716 return 0;
3717 }
3718
3719 /*
3720 * arg can be NULL and count can be zero for this function
3721 */
3722 static int
3723 pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3724 {
3725 struct thread_struct *thread = NULL;
3726 struct task_struct *task;
3727 pfarg_dbreg_t *req = (pfarg_dbreg_t *)arg;
3728 unsigned long flags;
3729 dbreg_t dbreg;
3730 unsigned int rnum;
3731 int first_time;
3732 int ret = 0, state;
3733 int i, can_access_pmu = 0;
3734 int is_system, is_loaded;
3735
3736 if (pmu_conf->use_rr_dbregs == 0) return -EINVAL;
3737
3738 state = ctx->ctx_state;
3739 is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
3740 is_system = ctx->ctx_fl_system;
3741 task = ctx->ctx_task;
3742
3743 if (state == PFM_CTX_ZOMBIE) return -EINVAL;
3744
3745 /*
3746 * on both UP and SMP, we can only write to the PMC when the task is
3747 * the owner of the local PMU.
3748 */
3749 if (is_loaded) {
3750 thread = &task->thread;
3751 /*
3752 * In system wide and when the context is loaded, access can only happen
3753 * when the caller is running on the CPU being monitored by the session.
3754 * It does not have to be the owner (ctx_task) of the context per se.
3755 */
3756 if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) {
3757 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
3758 return -EBUSY;
3759 }
3760 can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
3761 }
3762
3763 /*
3764 * we do not need to check for ipsr.db because we do clear ibr.x, dbr.r, and dbr.w
3765 * ensuring that no real breakpoint can be installed via this call.
3766 *
3767 * IMPORTANT: regs can be NULL in this function
3768 */
3769
3770 first_time = ctx->ctx_fl_using_dbreg == 0;
3771
3772 /*
3773 * don't bother if we are loaded and task is being debugged
3774 */
3775 if (is_loaded && (thread->flags & IA64_THREAD_DBG_VALID) != 0) {
3776 DPRINT(("debug registers already in use for [%d]\n", task_pid_nr(task)));
3777 return -EBUSY;
3778 }
3779
3780 /*
3781 * check for debug registers in system wide mode
3782 *
3783 * If though a check is done in pfm_context_load(),
3784 * we must repeat it here, in case the registers are
3785 * written after the context is loaded
3786 */
3787 if (is_loaded) {
3788 LOCK_PFS(flags);
3789
3790 if (first_time && is_system) {
3791 if (pfm_sessions.pfs_ptrace_use_dbregs)
3792 ret = -EBUSY;
3793 else
3794 pfm_sessions.pfs_sys_use_dbregs++;
3795 }
3796 UNLOCK_PFS(flags);
3797 }
3798
3799 if (ret != 0) return ret;
3800
3801 /*
3802 * mark ourself as user of the debug registers for
3803 * perfmon purposes.
3804 */
3805 ctx->ctx_fl_using_dbreg = 1;
3806
3807 /*
3808 * clear hardware registers to make sure we don't
3809 * pick up stale state.
3810 *
3811 * for a system wide session, we do not use
3812 * thread.dbr, thread.ibr because this process
3813 * never leaves the current CPU and the state
3814 * is shared by all processes running on it
3815 */
3816 if (first_time && can_access_pmu) {
3817 DPRINT(("[%d] clearing ibrs, dbrs\n", task_pid_nr(task)));
3818 for (i=0; i < pmu_conf->num_ibrs; i++) {
3819 ia64_set_ibr(i, 0UL);
3820 ia64_dv_serialize_instruction();
3821 }
3822 ia64_srlz_i();
3823 for (i=0; i < pmu_conf->num_dbrs; i++) {
3824 ia64_set_dbr(i, 0UL);
3825 ia64_dv_serialize_data();
3826 }
3827 ia64_srlz_d();
3828 }
3829
3830 /*
3831 * Now install the values into the registers
3832 */
3833 for (i = 0; i < count; i++, req++) {
3834
3835 rnum = req->dbreg_num;
3836 dbreg.val = req->dbreg_value;
3837
3838 ret = -EINVAL;
3839
3840 if ((mode == PFM_CODE_RR && rnum >= PFM_NUM_IBRS) || ((mode == PFM_DATA_RR) && rnum >= PFM_NUM_DBRS)) {
3841 DPRINT(("invalid register %u val=0x%lx mode=%d i=%d count=%d\n",
3842 rnum, dbreg.val, mode, i, count));
3843
3844 goto abort_mission;
3845 }
3846
3847 /*
3848 * make sure we do not install enabled breakpoint
3849 */
3850 if (rnum & 0x1) {
3851 if (mode == PFM_CODE_RR)
3852 dbreg.ibr.ibr_x = 0;
3853 else
3854 dbreg.dbr.dbr_r = dbreg.dbr.dbr_w = 0;
3855 }
3856
3857 PFM_REG_RETFLAG_SET(req->dbreg_flags, 0);
3858
3859 /*
3860 * Debug registers, just like PMC, can only be modified
3861 * by a kernel call. Moreover, perfmon() access to those
3862 * registers are centralized in this routine. The hardware
3863 * does not modify the value of these registers, therefore,
3864 * if we save them as they are written, we can avoid having
3865 * to save them on context switch out. This is made possible
3866 * by the fact that when perfmon uses debug registers, ptrace()
3867 * won't be able to modify them concurrently.
3868 */
3869 if (mode == PFM_CODE_RR) {
3870 CTX_USED_IBR(ctx, rnum);
3871
3872 if (can_access_pmu) {
3873 ia64_set_ibr(rnum, dbreg.val);
3874 ia64_dv_serialize_instruction();
3875 }
3876
3877 ctx->ctx_ibrs[rnum] = dbreg.val;
3878
3879 DPRINT(("write ibr%u=0x%lx used_ibrs=0x%x ld=%d apmu=%d\n",
3880 rnum, dbreg.val, ctx->ctx_used_ibrs[0], is_loaded, can_access_pmu));
3881 } else {
3882 CTX_USED_DBR(ctx, rnum);
3883
3884 if (can_access_pmu) {
3885 ia64_set_dbr(rnum, dbreg.val);
3886 ia64_dv_serialize_data();
3887 }
3888 ctx->ctx_dbrs[rnum] = dbreg.val;
3889
3890 DPRINT(("write dbr%u=0x%lx used_dbrs=0x%x ld=%d apmu=%d\n",
3891 rnum, dbreg.val, ctx->ctx_used_dbrs[0], is_loaded, can_access_pmu));
3892 }
3893 }
3894
3895 return 0;
3896
3897 abort_mission:
3898 /*
3899 * in case it was our first attempt, we undo the global modifications
3900 */
3901 if (first_time) {
3902 LOCK_PFS(flags);
3903 if (ctx->ctx_fl_system) {
3904 pfm_sessions.pfs_sys_use_dbregs--;
3905 }
3906 UNLOCK_PFS(flags);
3907 ctx->ctx_fl_using_dbreg = 0;
3908 }
3909 /*
3910 * install error return flag
3911 */
3912 PFM_REG_RETFLAG_SET(req->dbreg_flags, PFM_REG_RETFL_EINVAL);
3913
3914 return ret;
3915 }
3916
3917 static int
3918 pfm_write_ibrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3919 {
3920 return pfm_write_ibr_dbr(PFM_CODE_RR, ctx, arg, count, regs);
3921 }
3922
3923 static int
3924 pfm_write_dbrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3925 {
3926 return pfm_write_ibr_dbr(PFM_DATA_RR, ctx, arg, count, regs);
3927 }
3928
3929 int
3930 pfm_mod_write_ibrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
3931 {
3932 pfm_context_t *ctx;
3933
3934 if (req == NULL) return -EINVAL;
3935
3936 ctx = GET_PMU_CTX();
3937
3938 if (ctx == NULL) return -EINVAL;
3939
3940 /*
3941 * for now limit to current task, which is enough when calling
3942 * from overflow handler
3943 */
3944 if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
3945
3946 return pfm_write_ibrs(ctx, req, nreq, regs);
3947 }
3948 EXPORT_SYMBOL(pfm_mod_write_ibrs);
3949
3950 int
3951 pfm_mod_write_dbrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
3952 {
3953 pfm_context_t *ctx;
3954
3955 if (req == NULL) return -EINVAL;
3956
3957 ctx = GET_PMU_CTX();
3958
3959 if (ctx == NULL) return -EINVAL;
3960
3961 /*
3962 * for now limit to current task, which is enough when calling
3963 * from overflow handler
3964 */
3965 if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
3966
3967 return pfm_write_dbrs(ctx, req, nreq, regs);
3968 }
3969 EXPORT_SYMBOL(pfm_mod_write_dbrs);
3970
3971
3972 static int
3973 pfm_get_features(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3974 {
3975 pfarg_features_t *req = (pfarg_features_t *)arg;
3976
3977 req->ft_version = PFM_VERSION;
3978 return 0;
3979 }
3980
3981 static int
3982 pfm_stop(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
3983 {
3984 struct pt_regs *tregs;
3985 struct task_struct *task = PFM_CTX_TASK(ctx);
3986 int state, is_system;
3987
3988 state = ctx->ctx_state;
3989 is_system = ctx->ctx_fl_system;
3990
3991 /*
3992 * context must be attached to issue the stop command (includes LOADED,MASKED,ZOMBIE)
3993 */
3994 if (state == PFM_CTX_UNLOADED) return -EINVAL;
3995
3996 /*
3997 * In system wide and when the context is loaded, access can only happen
3998 * when the caller is running on the CPU being monitored by the session.
3999 * It does not have to be the owner (ctx_task) of the context per se.
4000 */
4001 if (is_system && ctx->ctx_cpu != smp_processor_id()) {
4002 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
4003 return -EBUSY;
4004 }
4005 DPRINT(("task [%d] ctx_state=%d is_system=%d\n",
4006 task_pid_nr(PFM_CTX_TASK(ctx)),
4007 state,
4008 is_system));
4009 /*
4010 * in system mode, we need to update the PMU directly
4011 * and the user level state of the caller, which may not
4012 * necessarily be the creator of the context.
4013 */
4014 if (is_system) {
4015 /*
4016 * Update local PMU first
4017 *
4018 * disable dcr pp
4019 */
4020 ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP);
4021 ia64_srlz_i();
4022
4023 /*
4024 * update local cpuinfo
4025 */
4026 PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
4027
4028 /*
4029 * stop monitoring, does srlz.i
4030 */
4031 pfm_clear_psr_pp();
4032
4033 /*
4034 * stop monitoring in the caller
4035 */
4036 ia64_psr(regs)->pp = 0;
4037
4038 return 0;
4039 }
4040 /*
4041 * per-task mode
4042 */
4043
4044 if (task == current) {
4045 /* stop monitoring at kernel level */
4046 pfm_clear_psr_up();
4047
4048 /*
4049 * stop monitoring at the user level
4050 */
4051 ia64_psr(regs)->up = 0;
4052 } else {
4053 tregs = task_pt_regs(task);
4054
4055 /*
4056 * stop monitoring at the user level
4057 */
4058 ia64_psr(tregs)->up = 0;
4059
4060 /*
4061 * monitoring disabled in kernel at next reschedule
4062 */
4063 ctx->ctx_saved_psr_up = 0;
4064 DPRINT(("task=[%d]\n", task_pid_nr(task)));
4065 }
4066 return 0;
4067 }
4068
4069
4070 static int
4071 pfm_start(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
4072 {
4073 struct pt_regs *tregs;
4074 int state, is_system;
4075
4076 state = ctx->ctx_state;
4077 is_system = ctx->ctx_fl_system;
4078
4079 if (state != PFM_CTX_LOADED) return -EINVAL;
4080
4081 /*
4082 * In system wide and when the context is loaded, access can only happen
4083 * when the caller is running on the CPU being monitored by the session.
4084 * It does not have to be the owner (ctx_task) of the context per se.
4085 */
4086 if (is_system && ctx->ctx_cpu != smp_processor_id()) {
4087 DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
4088 return -EBUSY;
4089 }
4090
4091 /*
4092 * in system mode, we need to update the PMU directly
4093 * and the user level state of the caller, which may not
4094 * necessarily be the creator of the context.
4095 */
4096 if (is_system) {
4097
4098 /*
4099 * set user level psr.pp for the caller
4100 */
4101 ia64_psr(regs)->pp = 1;
4102
4103 /*
4104 * now update the local PMU and cpuinfo
4105 */
4106 PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP);
4107
4108 /*
4109 * start monitoring at kernel level
4110 */
4111 pfm_set_psr_pp();
4112
4113 /* enable dcr pp */
4114 ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP);
4115 ia64_srlz_i();
4116
4117 return 0;
4118 }
4119
4120 /*
4121 * per-process mode
4122 */
4123
4124 if (ctx->ctx_task == current) {
4125
4126 /* start monitoring at kernel level */
4127 pfm_set_psr_up();
4128
4129 /*
4130 * activate monitoring at user level
4131 */
4132 ia64_psr(regs)->up = 1;
4133
4134 } else {
4135 tregs = task_pt_regs(ctx->ctx_task);
4136
4137 /*
4138 * start monitoring at the kernel level the next
4139 * time the task is scheduled
4140 */
4141 ctx->ctx_saved_psr_up = IA64_PSR_UP;
4142
4143 /*
4144 * activate monitoring at user level
4145 */
4146 ia64_psr(tregs)->up = 1;
4147 }
4148 return 0;
4149 }
4150
4151 static int
4152 pfm_get_pmc_reset(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
4153 {
4154 pfarg_reg_t *req = (pfarg_reg_t *)arg;
4155 unsigned int cnum;
4156 int i;
4157 int ret = -EINVAL;
4158
4159 for (i = 0; i < count; i++, req++) {
4160
4161 cnum = req->reg_num;
4162
4163 if (!PMC_IS_IMPL(cnum)) goto abort_mission;
4164
4165 req->reg_value = PMC_DFL_VAL(cnum);
4166
4167 PFM_REG_RETFLAG_SET(req->reg_flags, 0);
4168
4169 DPRINT(("pmc_reset_val pmc[%u]=0x%lx\n", cnum, req->reg_value));
4170 }
4171 return 0;
4172
4173 abort_mission:
4174 PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
4175 return ret;
4176 }
4177
4178 static int
4179 pfm_check_task_exist(pfm_context_t *ctx)
4180 {
4181 struct task_struct *g, *t;
4182 int ret = -ESRCH;
4183
4184 read_lock(&tasklist_lock);
4185
4186 do_each_thread (g, t) {
4187 if (t->thread.pfm_context == ctx) {
4188 ret = 0;
4189 goto out;
4190 }
4191 } while_each_thread (g, t);
4192 out:
4193 read_unlock(&tasklist_lock);
4194
4195 DPRINT(("pfm_check_task_exist: ret=%d ctx=%p\n", ret, ctx));
4196
4197 return ret;
4198 }
4199
4200 static int
4201 pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
4202 {
4203 struct task_struct *task;
4204 struct thread_struct *thread;
4205 struct pfm_context_t *old;
4206 unsigned long flags;
4207 #ifndef CONFIG_SMP
4208 struct task_struct *owner_task = NULL;
4209 #endif
4210 pfarg_load_t *req = (pfarg_load_t *)arg;
4211 unsigned long *pmcs_source, *pmds_source;
4212 int the_cpu;
4213 int ret = 0;
4214 int state, is_system, set_dbregs = 0;
4215
4216 state = ctx->ctx_state;
4217 is_system = ctx->ctx_fl_system;
4218 /*
4219 * can only load from unloaded or terminated state
4220 */
4221 if (state != PFM_CTX_UNLOADED) {
4222 DPRINT(("cannot load to [%d], invalid ctx_state=%d\n",
4223 req->load_pid,
4224 ctx->ctx_state));
4225 return -EBUSY;
4226 }
4227
4228 DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg));
4229
4230 if (CTX_OVFL_NOBLOCK(ctx) == 0 && req->load_pid == current->pid) {
4231 DPRINT(("cannot use blocking mode on self\n"));
4232 return -EINVAL;
4233 }
4234
4235 ret = pfm_get_task(ctx, req->load_pid, &task);
4236 if (ret) {
4237 DPRINT(("load_pid [%d] get_task=%d\n", req->load_pid, ret));
4238 return ret;
4239 }
4240
4241 ret = -EINVAL;
4242
4243 /*
4244 * system wide is self monitoring only
4245 */
4246 if (is_system && task != current) {
4247 DPRINT(("system wide is self monitoring only load_pid=%d\n",
4248 req->load_pid));
4249 goto error;
4250 }
4251
4252 thread = &task->thread;
4253
4254 ret = 0;
4255 /*
4256 * cannot load a context which is using range restrictions,
4257 * into a task that is being debugged.
4258 */
4259 if (ctx->ctx_fl_using_dbreg) {
4260 if (thread->flags & IA64_THREAD_DBG_VALID) {
4261 ret = -EBUSY;
4262 DPRINT(("load_pid [%d] task is debugged, cannot load range restrictions\n", req->load_pid));
4263 goto error;
4264 }
4265 LOCK_PFS(flags);
4266
4267 if (is_system) {
4268 if (pfm_sessions.pfs_ptrace_use_dbregs) {
4269 DPRINT(("cannot load [%d] dbregs in use\n",
4270 task_pid_nr(task)));
4271 ret = -EBUSY;
4272 } else {
4273 pfm_sessions.pfs_sys_use_dbregs++;
4274 DPRINT(("load [%d] increased sys_use_dbreg=%u\n", task_pid_nr(task), pfm_sessions.pfs_sys_use_dbregs));
4275 set_dbregs = 1;
4276 }
4277 }
4278
4279 UNLOCK_PFS(flags);
4280
4281 if (ret) goto error;
4282 }
4283
4284 /*
4285 * SMP system-wide monitoring implies self-monitoring.
4286 *
4287 * The programming model expects the task to
4288 * be pinned on a CPU throughout the session.
4289 * Here we take note of the current CPU at the
4290 * time the context is loaded. No call from
4291 * another CPU will be allowed.
4292 *
4293 * The pinning via shed_setaffinity()
4294 * must be done by the calling task prior
4295 * to this call.
4296 *
4297 * systemwide: keep track of CPU this session is supposed to run on
4298 */
4299 the_cpu = ctx->ctx_cpu = smp_processor_id();
4300
4301 ret = -EBUSY;
4302 /*
4303 * now reserve the session
4304 */
4305 ret = pfm_reserve_session(current, is_system, the_cpu);
4306 if (ret) goto error;
4307
4308 /*
4309 * task is necessarily stopped at this point.
4310 *
4311 * If the previous context was zombie, then it got removed in
4312 * pfm_save_regs(). Therefore we should not see it here.
4313 * If we see a context, then this is an active context
4314 *
4315 * XXX: needs to be atomic
4316 */
4317 DPRINT(("before cmpxchg() old_ctx=%p new_ctx=%p\n",
4318 thread->pfm_context, ctx));
4319
4320 ret = -EBUSY;
4321 old = ia64_cmpxchg(acq, &thread->pfm_context, NULL, ctx, sizeof(pfm_context_t *));
4322 if (old != NULL) {
4323 DPRINT(("load_pid [%d] already has a context\n", req->load_pid));
4324 goto error_unres;
4325 }
4326
4327 pfm_reset_msgq(ctx);
4328
4329 ctx->ctx_state = PFM_CTX_LOADED;
4330
4331 /*
4332 * link context to task
4333 */
4334 ctx->ctx_task = task;
4335
4336 if (is_system) {
4337 /*
4338 * we load as stopped
4339 */
4340 PFM_CPUINFO_SET(PFM_CPUINFO_SYST_WIDE);
4341 PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
4342
4343 if (ctx->ctx_fl_excl_idle) PFM_CPUINFO_SET(PFM_CPUINFO_EXCL_IDLE);
4344 } else {
4345 thread->flags |= IA64_THREAD_PM_VALID;
4346 }
4347
4348 /*
4349 * propagate into thread-state
4350 */
4351 pfm_copy_pmds(task, ctx);
4352 pfm_copy_pmcs(task, ctx);
4353
4354 pmcs_source = ctx->th_pmcs;
4355 pmds_source = ctx->th_pmds;
4356
4357 /*
4358 * always the case for system-wide
4359 */
4360 if (task == current) {
4361
4362 if (is_system == 0) {
4363
4364 /* allow user level control */
4365 ia64_psr(regs)->sp = 0;
4366 DPRINT(("clearing psr.sp for [%d]\n", task_pid_nr(task)));
4367
4368 SET_LAST_CPU(ctx, smp_processor_id());
4369 INC_ACTIVATION();
4370 SET_ACTIVATION(ctx);
4371 #ifndef CONFIG_SMP
4372 /*
4373 * push the other task out, if any
4374 */
4375 owner_task = GET_PMU_OWNER();
4376 if (owner_task) pfm_lazy_save_regs(owner_task);
4377 #endif
4378 }
4379 /*
4380 * load all PMD from ctx to PMU (as opposed to thread state)
4381 * restore all PMC from ctx to PMU
4382 */
4383 pfm_restore_pmds(pmds_source, ctx->ctx_all_pmds[0]);
4384 pfm_restore_pmcs(pmcs_source, ctx->ctx_all_pmcs[0]);
4385
4386 ctx->ctx_reload_pmcs[0] = 0UL;
4387 ctx->ctx_reload_pmds[0] = 0UL;
4388
4389 /*
4390 * guaranteed safe by earlier check against DBG_VALID
4391 */
4392 if (ctx->ctx_fl_using_dbreg) {
4393 pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
4394 pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
4395 }
4396 /*
4397 * set new ownership
4398 */
4399 SET_PMU_OWNER(task, ctx);
4400
4401 DPRINT(("context loaded on PMU for [%d]\n", task_pid_nr(task)));
4402 } else {
4403 /*
4404 * when not current, task MUST be stopped, so this is safe
4405 */
4406 regs = task_pt_regs(task);
4407
4408 /* force a full reload */
4409 ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
4410 SET_LAST_CPU(ctx, -1);
4411
4412 /* initial saved psr (stopped) */
4413 ctx->ctx_saved_psr_up = 0UL;
4414 ia64_psr(regs)->up = ia64_psr(regs)->pp = 0;
4415 }
4416
4417 ret = 0;
4418
4419 error_unres:
4420 if (ret) pfm_unreserve_session(ctx, ctx->ctx_fl_system, the_cpu);
4421 error:
4422 /*
4423 * we must undo the dbregs setting (for system-wide)
4424 */
4425 if (ret && set_dbregs) {
4426 LOCK_PFS(flags);
4427 pfm_sessions.pfs_sys_use_dbregs--;
4428 UNLOCK_PFS(flags);
4429 }
4430 /*
4431 * release task, there is now a link with the context
4432 */
4433 if (is_system == 0 && task != current) {
4434 pfm_put_task(task);
4435
4436 if (ret == 0) {
4437 ret = pfm_check_task_exist(ctx);
4438 if (ret) {
4439 ctx->ctx_state = PFM_CTX_UNLOADED;
4440 ctx->ctx_task = NULL;
4441 }
4442 }
4443 }
4444 return ret;
4445 }
4446
4447 /*
4448 * in this function, we do not need to increase the use count
4449 * for the task via get_task_struct(), because we hold the
4450 * context lock. If the task were to disappear while having
4451 * a context attached, it would go through pfm_exit_thread()
4452 * which also grabs the context lock and would therefore be blocked
4453 * until we are here.
4454 */
4455 static void pfm_flush_pmds(struct task_struct *, pfm_context_t *ctx);
4456
4457 static int
4458 pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
4459 {
4460 struct task_struct *task = PFM_CTX_TASK(ctx);
4461 struct pt_regs *tregs;
4462 int prev_state, is_system;
4463 int ret;
4464
4465 DPRINT(("ctx_state=%d task [%d]\n", ctx->ctx_state, task ? task_pid_nr(task) : -1));
4466
4467 prev_state = ctx->ctx_state;
4468 is_system = ctx->ctx_fl_system;
4469
4470 /*
4471 * unload only when necessary
4472 */
4473 if (prev_state == PFM_CTX_UNLOADED) {
4474 DPRINT(("ctx_state=%d, nothing to do\n", prev_state));
4475 return 0;
4476 }
4477
4478 /*
4479 * clear psr and dcr bits
4480 */
4481 ret = pfm_stop(ctx, NULL, 0, regs);
4482 if (ret) return ret;
4483
4484 ctx->ctx_state = PFM_CTX_UNLOADED;
4485
4486 /*
4487 * in system mode, we need to update the PMU directly
4488 * and the user level state of the caller, which may not
4489 * necessarily be the creator of the context.
4490 */
4491 if (is_system) {
4492
4493 /*
4494 * Update cpuinfo
4495 *
4496 * local PMU is taken care of in pfm_stop()
4497 */
4498 PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE);
4499 PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE);
4500
4501 /*
4502 * save PMDs in context
4503 * release ownership
4504 */
4505 pfm_flush_pmds(current, ctx);
4506
4507 /*
4508 * at this point we are done with the PMU
4509 * so we can unreserve the resource.
4510 */
4511 if (prev_state != PFM_CTX_ZOMBIE)
4512 pfm_unreserve_session(ctx, 1 , ctx->ctx_cpu);
4513
4514 /*
4515 * disconnect context from task
4516 */
4517 task->thread.pfm_context = NULL;
4518 /*
4519 * disconnect task from context
4520 */
4521 ctx->ctx_task = NULL;
4522
4523 /*
4524 * There is nothing more to cleanup here.
4525 */
4526 return 0;
4527 }
4528
4529 /*
4530 * per-task mode
4531 */
4532 tregs = task == current ? regs : task_pt_regs(task);
4533
4534 if (task == current) {
4535 /*
4536 * cancel user level control
4537 */
4538 ia64_psr(regs)->sp = 1;
4539
4540 DPRINT(("setting psr.sp for [%d]\n", task_pid_nr(task)));
4541 }
4542 /*
4543 * save PMDs to context
4544 * release ownership
4545 */
4546 pfm_flush_pmds(task, ctx);
4547
4548 /*
4549 * at this point we are done with the PMU
4550 * so we can unreserve the resource.
4551 *
4552 * when state was ZOMBIE, we have already unreserved.
4553 */
4554 if (prev_state != PFM_CTX_ZOMBIE)
4555 pfm_unreserve_session(ctx, 0 , ctx->ctx_cpu);
4556
4557 /*
4558 * reset activation counter and psr
4559 */
4560 ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
4561 SET_LAST_CPU(ctx, -1);
4562
4563 /*
4564 * PMU state will not be restored
4565 */
4566 task->thread.flags &= ~IA64_THREAD_PM_VALID;
4567
4568 /*
4569 * break links between context and task
4570 */
4571 task->thread.pfm_context = NULL;
4572 ctx->ctx_task = NULL;
4573
4574 PFM_SET_WORK_PENDING(task, 0);
4575
4576 ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
4577 ctx->ctx_fl_can_restart = 0;
4578 ctx->ctx_fl_going_zombie = 0;
4579
4580 DPRINT(("disconnected [%d] from context\n", task_pid_nr(task)));
4581
4582 return 0;
4583 }
4584
4585
4586 /*
4587 * called only from exit_thread(): task == current
4588 * we come here only if current has a context attached (loaded or masked)
4589 */
4590 void
4591 pfm_exit_thread(struct task_struct *task)
4592 {
4593 pfm_context_t *ctx;
4594 unsigned long flags;
4595 struct pt_regs *regs = task_pt_regs(task);
4596 int ret, state;
4597 int free_ok = 0;
4598
4599 ctx = PFM_GET_CTX(task);
4600
4601 PROTECT_CTX(ctx, flags);
4602
4603 DPRINT(("state=%d task [%d]\n", ctx->ctx_state, task_pid_nr(task)));
4604
4605 state = ctx->ctx_state;
4606 switch(state) {
4607 case PFM_CTX_UNLOADED:
4608 /*
4609 * only comes to this function if pfm_context is not NULL, i.e., cannot
4610 * be in unloaded state
4611 */
4612 printk(KERN_ERR "perfmon: pfm_exit_thread [%d] ctx unloaded\n", task_pid_nr(task));
4613 break;
4614 case PFM_CTX_LOADED:
4615 case PFM_CTX_MASKED:
4616 ret = pfm_context_unload(ctx, NULL, 0, regs);
4617 if (ret) {
4618 printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task_pid_nr(task), state, ret);
4619 }
4620 DPRINT(("ctx unloaded for current state was %d\n", state));
4621
4622 pfm_end_notify_user(ctx);
4623 break;
4624 case PFM_CTX_ZOMBIE:
4625 ret = pfm_context_unload(ctx, NULL, 0, regs);
4626 if (ret) {
4627 printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task_pid_nr(task), state, ret);
4628 }
4629 free_ok = 1;
4630 break;
4631 default:
4632 printk(KERN_ERR "perfmon: pfm_exit_thread [%d] unexpected state=%d\n", task_pid_nr(task), state);
4633 break;
4634 }
4635 UNPROTECT_CTX(ctx, flags);
4636
4637 { u64 psr = pfm_get_psr();
4638 BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
4639 BUG_ON(GET_PMU_OWNER());
4640 BUG_ON(ia64_psr(regs)->up);
4641 BUG_ON(ia64_psr(regs)->pp);
4642 }
4643
4644 /*
4645 * All memory free operations (especially for vmalloc'ed memory)
4646 * MUST be done with interrupts ENABLED.
4647 */
4648 if (free_ok) pfm_context_free(ctx);
4649 }
4650
4651 /*
4652 * functions MUST be listed in the increasing order of their index (see permfon.h)
4653 */
4654 #define PFM_CMD(name, flags, arg_count, arg_type, getsz) { name, #name, flags, arg_count, sizeof(arg_type), getsz }
4655 #define PFM_CMD_S(name, flags) { name, #name, flags, 0, 0, NULL }
4656 #define PFM_CMD_PCLRWS (PFM_CMD_FD|PFM_CMD_ARG_RW|PFM_CMD_STOP)
4657 #define PFM_CMD_PCLRW (PFM_CMD_FD|PFM_CMD_ARG_RW)
4658 #define PFM_CMD_NONE { NULL, "no-cmd", 0, 0, 0, NULL}
4659
4660 static pfm_cmd_desc_t pfm_cmd_tab[]={
4661 /* 0 */PFM_CMD_NONE,
4662 /* 1 */PFM_CMD(pfm_write_pmcs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
4663 /* 2 */PFM_CMD(pfm_write_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
4664 /* 3 */PFM_CMD(pfm_read_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
4665 /* 4 */PFM_CMD_S(pfm_stop, PFM_CMD_PCLRWS),
4666 /* 5 */PFM_CMD_S(pfm_start, PFM_CMD_PCLRWS),
4667 /* 6 */PFM_CMD_NONE,
4668 /* 7 */PFM_CMD_NONE,
4669 /* 8 */PFM_CMD(pfm_context_create, PFM_CMD_ARG_RW, 1, pfarg_context_t, pfm_ctx_getsize),
4670 /* 9 */PFM_CMD_NONE,
4671 /* 10 */PFM_CMD_S(pfm_restart, PFM_CMD_PCLRW),
4672 /* 11 */PFM_CMD_NONE,
4673 /* 12 */PFM_CMD(pfm_get_features, PFM_CMD_ARG_RW, 1, pfarg_features_t, NULL),
4674 /* 13 */PFM_CMD(pfm_debug, 0, 1, unsigned int, NULL),
4675 /* 14 */PFM_CMD_NONE,
4676 /* 15 */PFM_CMD(pfm_get_pmc_reset, PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
4677 /* 16 */PFM_CMD(pfm_context_load, PFM_CMD_PCLRWS, 1, pfarg_load_t, NULL),
4678 /* 17 */PFM_CMD_S(pfm_context_unload, PFM_CMD_PCLRWS),
4679 /* 18 */PFM_CMD_NONE,
4680 /* 19 */PFM_CMD_NONE,
4681 /* 20 */PFM_CMD_NONE,
4682 /* 21 */PFM_CMD_NONE,
4683 /* 22 */PFM_CMD_NONE,
4684 /* 23 */PFM_CMD_NONE,
4685 /* 24 */PFM_CMD_NONE,
4686 /* 25 */PFM_CMD_NONE,
4687 /* 26 */PFM_CMD_NONE,
4688 /* 27 */PFM_CMD_NONE,
4689 /* 28 */PFM_CMD_NONE,
4690 /* 29 */PFM_CMD_NONE,
4691 /* 30 */PFM_CMD_NONE,
4692 /* 31 */PFM_CMD_NONE,
4693 /* 32 */PFM_CMD(pfm_write_ibrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL),
4694 /* 33 */PFM_CMD(pfm_write_dbrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL)
4695 };
4696 #define PFM_CMD_COUNT (sizeof(pfm_cmd_tab)/sizeof(pfm_cmd_desc_t))
4697
4698 static int
4699 pfm_check_task_state(pfm_context_t *ctx, int cmd, unsigned long flags)
4700 {
4701 struct task_struct *task;
4702 int state, old_state;
4703
4704 recheck:
4705 state = ctx->ctx_state;
4706 task = ctx->ctx_task;
4707
4708 if (task == NULL) {
4709 DPRINT(("context %d no task, state=%d\n", ctx->ctx_fd, state));
4710 return 0;
4711 }
4712
4713 DPRINT(("context %d state=%d [%d] task_state=%ld must_stop=%d\n",
4714 ctx->ctx_fd,
4715 state,
4716 task_pid_nr(task),
4717 task->state, PFM_CMD_STOPPED(cmd)));
4718
4719 /*
4720 * self-monitoring always ok.
4721 *
4722 * for system-wide the caller can either be the creator of the
4723 * context (to one to which the context is attached to) OR
4724 * a task running on the same CPU as the session.
4725 */
4726 if (task == current || ctx->ctx_fl_system) return 0;
4727
4728 /*
4729 * we are monitoring another thread
4730 */
4731 switch(state) {
4732 case PFM_CTX_UNLOADED:
4733 /*
4734 * if context is UNLOADED we are safe to go
4735 */
4736 return 0;
4737 case PFM_CTX_ZOMBIE:
4738 /*
4739 * no command can operate on a zombie context
4740 */
4741 DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
4742 return -EINVAL;
4743 case PFM_CTX_MASKED:
4744 /*
4745 * PMU state has been saved to software even though
4746 * the thread may still be running.
4747 */
4748 if (cmd != PFM_UNLOAD_CONTEXT) return 0;
4749 }
4750
4751 /*
4752 * context is LOADED or MASKED. Some commands may need to have
4753 * the task stopped.
4754 *
4755 * We could lift this restriction for UP but it would mean that
4756 * the user has no guarantee the task would not run between
4757 * two successive calls to perfmonctl(). That's probably OK.
4758 * If this user wants to ensure the task does not run, then
4759 * the task must be stopped.
4760 */
4761 if (PFM_CMD_STOPPED(cmd)) {
4762 if (!task_is_stopped_or_traced(task)) {
4763 DPRINT(("[%d] task not in stopped state\n", task_pid_nr(task)));
4764 return -EBUSY;
4765 }
4766 /*
4767 * task is now stopped, wait for ctxsw out
4768 *
4769 * This is an interesting point in the code.
4770 * We need to unprotect the context because
4771 * the pfm_save_regs() routines needs to grab
4772 * the same lock. There are danger in doing
4773 * this because it leaves a window open for
4774 * another task to get access to the context
4775 * and possibly change its state. The one thing
4776 * that is not possible is for the context to disappear
4777 * because we are protected by the VFS layer, i.e.,
4778 * get_fd()/put_fd().
4779 */
4780 old_state = state;
4781
4782 UNPROTECT_CTX(ctx, flags);
4783
4784 wait_task_inactive(task, 0);
4785
4786 PROTECT_CTX(ctx, flags);
4787
4788 /*
4789 * we must recheck to verify if state has changed
4790 */
4791 if (ctx->ctx_state != old_state) {
4792 DPRINT(("old_state=%d new_state=%d\n", old_state, ctx->ctx_state));
4793 goto recheck;
4794 }
4795 }
4796 return 0;
4797 }
4798
4799 /*
4800 * system-call entry point (must return long)
4801 */
4802 asmlinkage long
4803 sys_perfmonctl (int fd, int cmd, void __user *arg, int count)
4804 {
4805 struct file *file = NULL;
4806 pfm_context_t *ctx = NULL;
4807 unsigned long flags = 0UL;
4808 void *args_k = NULL;
4809 long ret; /* will expand int return types */
4810 size_t base_sz, sz, xtra_sz = 0;
4811 int narg, completed_args = 0, call_made = 0, cmd_flags;
4812 int (*func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
4813 int (*getsize)(void *arg, size_t *sz);
4814 #define PFM_MAX_ARGSIZE 4096
4815
4816 /*
4817 * reject any call if perfmon was disabled at initialization
4818 */
4819 if (unlikely(pmu_conf == NULL)) return -ENOSYS;
4820
4821 if (unlikely(cmd < 0 || cmd >= PFM_CMD_COUNT)) {
4822 DPRINT(("invalid cmd=%d\n", cmd));
4823 return -EINVAL;
4824 }
4825
4826 func = pfm_cmd_tab[cmd].cmd_func;
4827 narg = pfm_cmd_tab[cmd].cmd_narg;
4828 base_sz = pfm_cmd_tab[cmd].cmd_argsize;
4829 getsize = pfm_cmd_tab[cmd].cmd_getsize;
4830 cmd_flags = pfm_cmd_tab[cmd].cmd_flags;
4831
4832 if (unlikely(func == NULL)) {
4833 DPRINT(("invalid cmd=%d\n", cmd));
4834 return -EINVAL;
4835 }
4836
4837 DPRINT(("cmd=%s idx=%d narg=0x%x argsz=%lu count=%d\n",
4838 PFM_CMD_NAME(cmd),
4839 cmd,
4840 narg,
4841 base_sz,
4842 count));
4843
4844 /*
4845 * check if number of arguments matches what the command expects
4846 */
4847 if (unlikely((narg == PFM_CMD_ARG_MANY && count <= 0) || (narg > 0 && narg != count)))
4848 return -EINVAL;
4849
4850 restart_args:
4851 sz = xtra_sz + base_sz*count;
4852 /*
4853 * limit abuse to min page size
4854 */
4855 if (unlikely(sz > PFM_MAX_ARGSIZE)) {
4856 printk(KERN_ERR "perfmon: [%d] argument too big %lu\n", task_pid_nr(current), sz);
4857 return -E2BIG;
4858 }
4859
4860 /*
4861 * allocate default-sized argument buffer
4862 */
4863 if (likely(count && args_k == NULL)) {
4864 args_k = kmalloc(PFM_MAX_ARGSIZE, GFP_KERNEL);
4865 if (args_k == NULL) return -ENOMEM;
4866 }
4867
4868 ret = -EFAULT;
4869
4870 /*
4871 * copy arguments
4872 *
4873 * assume sz = 0 for command without parameters
4874 */
4875 if (sz && copy_from_user(args_k, arg, sz)) {
4876 DPRINT(("cannot copy_from_user %lu bytes @%p\n", sz, arg));
4877 goto error_args;
4878 }
4879
4880 /*
4881 * check if command supports extra parameters
4882 */
4883 if (completed_args == 0 && getsize) {
4884 /*
4885 * get extra parameters size (based on main argument)
4886 */
4887 ret = (*getsize)(args_k, &xtra_sz);
4888 if (ret) goto error_args;
4889
4890 completed_args = 1;
4891
4892 DPRINT(("restart_args sz=%lu xtra_sz=%lu\n", sz, xtra_sz));
4893
4894 /* retry if necessary */
4895 if (likely(xtra_sz)) goto restart_args;
4896 }
4897
4898 if (unlikely((cmd_flags & PFM_CMD_FD) == 0)) goto skip_fd;
4899
4900 ret = -EBADF;
4901
4902 file = fget(fd);
4903 if (unlikely(file == NULL)) {
4904 DPRINT(("invalid fd %d\n", fd));
4905 goto error_args;
4906 }
4907 if (unlikely(PFM_IS_FILE(file) == 0)) {
4908 DPRINT(("fd %d not related to perfmon\n", fd));
4909 goto error_args;
4910 }
4911
4912 ctx = (pfm_context_t *)file->private_data;
4913 if (unlikely(ctx == NULL)) {
4914 DPRINT(("no context for fd %d\n", fd));
4915 goto error_args;
4916 }
4917 prefetch(&ctx->ctx_state);
4918
4919 PROTECT_CTX(ctx, flags);
4920
4921 /*
4922 * check task is stopped
4923 */
4924 ret = pfm_check_task_state(ctx, cmd, flags);
4925 if (unlikely(ret)) goto abort_locked;
4926
4927 skip_fd:
4928 ret = (*func)(ctx, args_k, count, task_pt_regs(current));
4929
4930 call_made = 1;
4931
4932 abort_locked:
4933 if (likely(ctx)) {
4934 DPRINT(("context unlocked\n"));
4935 UNPROTECT_CTX(ctx, flags);
4936 }
4937
4938 /* copy argument back to user, if needed */
4939 if (call_made && PFM_CMD_RW_ARG(cmd) && copy_to_user(arg, args_k, base_sz*count)) ret = -EFAULT;
4940
4941 error_args:
4942 if (file)
4943 fput(file);
4944
4945 kfree(args_k);
4946
4947 DPRINT(("cmd=%s ret=%ld\n", PFM_CMD_NAME(cmd), ret));
4948
4949 return ret;
4950 }
4951
4952 static void
4953 pfm_resume_after_ovfl(pfm_context_t *ctx, unsigned long ovfl_regs, struct pt_regs *regs)
4954 {
4955 pfm_buffer_fmt_t *fmt = ctx->ctx_buf_fmt;
4956 pfm_ovfl_ctrl_t rst_ctrl;
4957 int state;
4958 int ret = 0;
4959
4960 state = ctx->ctx_state;
4961 /*
4962 * Unlock sampling buffer and reset index atomically
4963 * XXX: not really needed when blocking
4964 */
4965 if (CTX_HAS_SMPL(ctx)) {
4966
4967 rst_ctrl.bits.mask_monitoring = 0;
4968 rst_ctrl.bits.reset_ovfl_pmds = 0;
4969
4970 if (state == PFM_CTX_LOADED)
4971 ret = pfm_buf_fmt_restart_active(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
4972 else
4973 ret = pfm_buf_fmt_restart(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
4974 } else {
4975 rst_ctrl.bits.mask_monitoring = 0;
4976 rst_ctrl.bits.reset_ovfl_pmds = 1;
4977 }
4978
4979 if (ret == 0) {
4980 if (rst_ctrl.bits.reset_ovfl_pmds) {
4981 pfm_reset_regs(ctx, &ovfl_regs, PFM_PMD_LONG_RESET);
4982 }
4983 if (rst_ctrl.bits.mask_monitoring == 0) {
4984 DPRINT(("resuming monitoring\n"));
4985 if (ctx->ctx_state == PFM_CTX_MASKED) pfm_restore_monitoring(current);
4986 } else {
4987 DPRINT(("stopping monitoring\n"));
4988 //pfm_stop_monitoring(current, regs);
4989 }
4990 ctx->ctx_state = PFM_CTX_LOADED;
4991 }
4992 }
4993
4994 /*
4995 * context MUST BE LOCKED when calling
4996 * can only be called for current
4997 */
4998 static void
4999 pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs)
5000 {
5001 int ret;
5002
5003 DPRINT(("entering for [%d]\n", task_pid_nr(current)));
5004
5005 ret = pfm_context_unload(ctx, NULL, 0, regs);
5006 if (ret) {
5007 printk(KERN_ERR "pfm_context_force_terminate: [%d] unloaded failed with %d\n", task_pid_nr(current), ret);
5008 }
5009
5010 /*
5011 * and wakeup controlling task, indicating we are now disconnected
5012 */
5013 wake_up_interruptible(&ctx->ctx_zombieq);
5014
5015 /*
5016 * given that context is still locked, the controlling
5017 * task will only get access when we return from
5018 * pfm_handle_work().
5019 */
5020 }
5021
5022 static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds);
5023
5024 /*
5025 * pfm_handle_work() can be called with interrupts enabled
5026 * (TIF_NEED_RESCHED) or disabled. The down_interruptible
5027 * call may sleep, therefore we must re-enable interrupts
5028 * to avoid deadlocks. It is safe to do so because this function
5029 * is called ONLY when returning to user level (pUStk=1), in which case
5030 * there is no risk of kernel stack overflow due to deep
5031 * interrupt nesting.
5032 */
5033 void
5034 pfm_handle_work(void)
5035 {
5036 pfm_context_t *ctx;
5037 struct pt_regs *regs;
5038 unsigned long flags, dummy_flags;
5039 unsigned long ovfl_regs;
5040 unsigned int reason;
5041 int ret;
5042
5043 ctx = PFM_GET_CTX(current);
5044 if (ctx == NULL) {
5045 printk(KERN_ERR "perfmon: [%d] has no PFM context\n",
5046 task_pid_nr(current));
5047 return;
5048 }
5049
5050 PROTECT_CTX(ctx, flags);
5051
5052 PFM_SET_WORK_PENDING(current, 0);
5053
5054 regs = task_pt_regs(current);
5055
5056 /*
5057 * extract reason for being here and clear
5058 */
5059 reason = ctx->ctx_fl_trap_reason;
5060 ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
5061 ovfl_regs = ctx->ctx_ovfl_regs[0];
5062
5063 DPRINT(("reason=%d state=%d\n", reason, ctx->ctx_state));
5064
5065 /*
5066 * must be done before we check for simple-reset mode
5067 */
5068 if (ctx->ctx_fl_going_zombie || ctx->ctx_state == PFM_CTX_ZOMBIE)
5069 goto do_zombie;
5070
5071 //if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking;
5072 if (reason == PFM_TRAP_REASON_RESET)
5073 goto skip_blocking;
5074
5075 /*
5076 * restore interrupt mask to what it was on entry.
5077 * Could be enabled/diasbled.
5078 */
5079 UNPROTECT_CTX(ctx, flags);
5080
5081 /*
5082 * force interrupt enable because of down_interruptible()
5083 */
5084 local_irq_enable();
5085
5086 DPRINT(("before block sleeping\n"));
5087
5088 /*
5089 * may go through without blocking on SMP systems
5090 * if restart has been received already by the time we call down()
5091 */
5092 ret = wait_for_completion_interruptible(&ctx->ctx_restart_done);
5093
5094 DPRINT(("after block sleeping ret=%d\n", ret));
5095
5096 /*
5097 * lock context and mask interrupts again
5098 * We save flags into a dummy because we may have
5099 * altered interrupts mask compared to entry in this
5100 * function.
5101 */
5102 PROTECT_CTX(ctx, dummy_flags);
5103
5104 /*
5105 * we need to read the ovfl_regs only after wake-up
5106 * because we may have had pfm_write_pmds() in between
5107 * and that can changed PMD values and therefore
5108 * ovfl_regs is reset for these new PMD values.
5109 */
5110 ovfl_regs = ctx->ctx_ovfl_regs[0];
5111
5112 if (ctx->ctx_fl_going_zombie) {
5113 do_zombie:
5114 DPRINT(("context is zombie, bailing out\n"));
5115 pfm_context_force_terminate(ctx, regs);
5116 goto nothing_to_do;
5117 }
5118 /*
5119 * in case of interruption of down() we don't restart anything
5120 */
5121 if (ret < 0)
5122 goto nothing_to_do;
5123
5124 skip_blocking:
5125 pfm_resume_after_ovfl(ctx, ovfl_regs, regs);
5126 ctx->ctx_ovfl_regs[0] = 0UL;
5127
5128 nothing_to_do:
5129 /*
5130 * restore flags as they were upon entry
5131 */
5132 UNPROTECT_CTX(ctx, flags);
5133 }
5134
5135 static int
5136 pfm_notify_user(pfm_context_t *ctx, pfm_msg_t *msg)
5137 {
5138 if (ctx->ctx_state == PFM_CTX_ZOMBIE) {
5139 DPRINT(("ignoring overflow notification, owner is zombie\n"));
5140 return 0;
5141 }
5142
5143 DPRINT(("waking up somebody\n"));
5144
5145 if (msg) wake_up_interruptible(&ctx->ctx_msgq_wait);
5146
5147 /*
5148 * safe, we are not in intr handler, nor in ctxsw when
5149 * we come here
5150 */
5151 kill_fasync (&ctx->ctx_async_queue, SIGIO, POLL_IN);
5152
5153 return 0;
5154 }
5155
5156 static int
5157 pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds)
5158 {
5159 pfm_msg_t *msg = NULL;
5160
5161 if (ctx->ctx_fl_no_msg == 0) {
5162 msg = pfm_get_new_msg(ctx);
5163 if (msg == NULL) {
5164 printk(KERN_ERR "perfmon: pfm_ovfl_notify_user no more notification msgs\n");
5165 return -1;
5166 }
5167
5168 msg->pfm_ovfl_msg.msg_type = PFM_MSG_OVFL;
5169 msg->pfm_ovfl_msg.msg_ctx_fd = ctx->ctx_fd;
5170 msg->pfm_ovfl_msg.msg_active_set = 0;
5171 msg->pfm_ovfl_msg.msg_ovfl_pmds[0] = ovfl_pmds;
5172 msg->pfm_ovfl_msg.msg_ovfl_pmds[1] = 0UL;
5173 msg->pfm_ovfl_msg.msg_ovfl_pmds[2] = 0UL;
5174 msg->pfm_ovfl_msg.msg_ovfl_pmds[3] = 0UL;
5175 msg->pfm_ovfl_msg.msg_tstamp = 0UL;
5176 }
5177
5178 DPRINT(("ovfl msg: msg=%p no_msg=%d fd=%d ovfl_pmds=0x%lx\n",
5179 msg,
5180 ctx->ctx_fl_no_msg,
5181 ctx->ctx_fd,
5182 ovfl_pmds));
5183
5184 return pfm_notify_user(ctx, msg);
5185 }
5186
5187 static int
5188 pfm_end_notify_user(pfm_context_t *ctx)
5189 {
5190 pfm_msg_t *msg;
5191
5192 msg = pfm_get_new_msg(ctx);
5193 if (msg == NULL) {
5194 printk(KERN_ERR "perfmon: pfm_end_notify_user no more notification msgs\n");
5195 return -1;
5196 }
5197 /* no leak */
5198 memset(msg, 0, sizeof(*msg));
5199
5200 msg->pfm_end_msg.msg_type = PFM_MSG_END;
5201 msg->pfm_end_msg.msg_ctx_fd = ctx->ctx_fd;
5202 msg->pfm_ovfl_msg.msg_tstamp = 0UL;
5203
5204 DPRINT(("end msg: msg=%p no_msg=%d ctx_fd=%d\n",
5205 msg,
5206 ctx->ctx_fl_no_msg,
5207 ctx->ctx_fd));
5208
5209 return pfm_notify_user(ctx, msg);
5210 }
5211
5212 /*
5213 * main overflow processing routine.
5214 * it can be called from the interrupt path or explicitly during the context switch code
5215 */
5216 static void pfm_overflow_handler(struct task_struct *task, pfm_context_t *ctx,
5217 unsigned long pmc0, struct pt_regs *regs)
5218 {
5219 pfm_ovfl_arg_t *ovfl_arg;
5220 unsigned long mask;
5221 unsigned long old_val, ovfl_val, new_val;
5222 unsigned long ovfl_notify = 0UL, ovfl_pmds = 0UL, smpl_pmds = 0UL, reset_pmds;
5223 unsigned long tstamp;
5224 pfm_ovfl_ctrl_t ovfl_ctrl;
5225 unsigned int i, has_smpl;
5226 int must_notify = 0;
5227
5228 if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) goto stop_monitoring;
5229
5230 /*
5231 * sanity test. Should never happen
5232 */
5233 if (unlikely((pmc0 & 0x1) == 0)) goto sanity_check;
5234
5235 tstamp = ia64_get_itc();
5236 mask = pmc0 >> PMU_FIRST_COUNTER;
5237 ovfl_val = pmu_conf->ovfl_val;
5238 has_smpl = CTX_HAS_SMPL(ctx);
5239
5240 DPRINT_ovfl(("pmc0=0x%lx pid=%d iip=0x%lx, %s "
5241 "used_pmds=0x%lx\n",
5242 pmc0,
5243 task ? task_pid_nr(task): -1,
5244 (regs ? regs->cr_iip : 0),
5245 CTX_OVFL_NOBLOCK(ctx) ? "nonblocking" : "blocking",
5246 ctx->ctx_used_pmds[0]));
5247
5248
5249 /*
5250 * first we update the virtual counters
5251 * assume there was a prior ia64_srlz_d() issued
5252 */
5253 for (i = PMU_FIRST_COUNTER; mask ; i++, mask >>= 1) {
5254
5255 /* skip pmd which did not overflow */
5256 if ((mask & 0x1) == 0) continue;
5257
5258 /*
5259 * Note that the pmd is not necessarily 0 at this point as qualified events
5260 * may have happened before the PMU was frozen. The residual count is not
5261 * taken into consideration here but will be with any read of the pmd via
5262 * pfm_read_pmds().
5263 */
5264 old_val = new_val = ctx->ctx_pmds[i].val;
5265 new_val += 1 + ovfl_val;
5266 ctx->ctx_pmds[i].val = new_val;
5267
5268 /*
5269 * check for overflow condition
5270 */
5271 if (likely(old_val > new_val)) {
5272 ovfl_pmds |= 1UL << i;
5273 if (PMC_OVFL_NOTIFY(ctx, i)) ovfl_notify |= 1UL << i;
5274 }
5275
5276 DPRINT_ovfl(("ctx_pmd[%d].val=0x%lx old_val=0x%lx pmd=0x%lx ovfl_pmds=0x%lx ovfl_notify=0x%lx\n",
5277 i,
5278 new_val,
5279 old_val,
5280 ia64_get_pmd(i) & ovfl_val,
5281 ovfl_pmds,
5282 ovfl_notify));
5283 }
5284
5285 /*
5286 * there was no 64-bit overflow, nothing else to do
5287 */
5288 if (ovfl_pmds == 0UL) return;
5289
5290 /*
5291 * reset all control bits
5292 */
5293 ovfl_ctrl.val = 0;
5294 reset_pmds = 0UL;
5295
5296 /*
5297 * if a sampling format module exists, then we "cache" the overflow by
5298 * calling the module's handler() routine.
5299 */
5300 if (has_smpl) {
5301 unsigned long start_cycles, end_cycles;
5302 unsigned long pmd_mask;
5303 int j, k, ret = 0;
5304 int this_cpu = smp_processor_id();
5305
5306 pmd_mask = ovfl_pmds >> PMU_FIRST_COUNTER;
5307 ovfl_arg = &ctx->ctx_ovfl_arg;
5308
5309 prefetch(ctx->ctx_smpl_hdr);
5310
5311 for(i=PMU_FIRST_COUNTER; pmd_mask && ret == 0; i++, pmd_mask >>=1) {
5312
5313 mask = 1UL << i;
5314
5315 if ((pmd_mask & 0x1) == 0) continue;
5316
5317 ovfl_arg->ovfl_pmd = (unsigned char )i;
5318 ovfl_arg->ovfl_notify = ovfl_notify & mask ? 1 : 0;
5319 ovfl_arg->active_set = 0;
5320 ovfl_arg->ovfl_ctrl.val = 0; /* module must fill in all fields */
5321 ovfl_arg->smpl_pmds[0] = smpl_pmds = ctx->ctx_pmds[i].smpl_pmds[0];
5322
5323 ovfl_arg->pmd_value = ctx->ctx_pmds[i].val;
5324 ovfl_arg->pmd_last_reset = ctx->ctx_pmds[i].lval;
5325 ovfl_arg->pmd_eventid = ctx->ctx_pmds[i].eventid;
5326
5327 /*
5328 * copy values of pmds of interest. Sampling format may copy them
5329 * into sampling buffer.
5330 */
5331 if (smpl_pmds) {
5332 for(j=0, k=0; smpl_pmds; j++, smpl_pmds >>=1) {
5333 if ((smpl_pmds & 0x1) == 0) continue;
5334 ovfl_arg->smpl_pmds_values[k++] = PMD_IS_COUNTING(j) ? pfm_read_soft_counter(ctx, j) : ia64_get_pmd(j);
5335 DPRINT_ovfl(("smpl_pmd[%d]=pmd%u=0x%lx\n", k-1, j, ovfl_arg->smpl_pmds_values[k-1]));
5336 }
5337 }
5338
5339 pfm_stats[this_cpu].pfm_smpl_handler_calls++;
5340
5341 start_cycles = ia64_get_itc();
5342
5343 /*
5344 * call custom buffer format record (handler) routine
5345 */
5346 ret = (*ctx->ctx_buf_fmt->fmt_handler)(task, ctx->ctx_smpl_hdr, ovfl_arg, regs, tstamp);
5347
5348 end_cycles = ia64_get_itc();
5349
5350 /*
5351 * For those controls, we take the union because they have
5352 * an all or nothing behavior.
5353 */
5354 ovfl_ctrl.bits.notify_user |= ovfl_arg->ovfl_ctrl.bits.notify_user;
5355 ovfl_ctrl.bits.block_task |= ovfl_arg->ovfl_ctrl.bits.block_task;
5356 ovfl_ctrl.bits.mask_monitoring |= ovfl_arg->ovfl_ctrl.bits.mask_monitoring;
5357 /*
5358 * build the bitmask of pmds to reset now
5359 */
5360 if (ovfl_arg->ovfl_ctrl.bits.reset_ovfl_pmds) reset_pmds |= mask;
5361
5362 pfm_stats[this_cpu].pfm_smpl_handler_cycles += end_cycles - start_cycles;
5363 }
5364 /*
5365 * when the module cannot handle the rest of the overflows, we abort right here
5366 */
5367 if (ret && pmd_mask) {
5368 DPRINT(("handler aborts leftover ovfl_pmds=0x%lx\n",
5369 pmd_mask<<PMU_FIRST_COUNTER));
5370 }
5371 /*
5372 * remove the pmds we reset now from the set of pmds to reset in pfm_restart()
5373 */
5374 ovfl_pmds &= ~reset_pmds;
5375 } else {
5376 /*
5377 * when no sampling module is used, then the default
5378 * is to notify on overflow if requested by user
5379 */
5380 ovfl_ctrl.bits.notify_user = ovfl_notify ? 1 : 0;
5381 ovfl_ctrl.bits.block_task = ovfl_notify ? 1 : 0;
5382 ovfl_ctrl.bits.mask_monitoring = ovfl_notify ? 1 : 0; /* XXX: change for saturation */
5383 ovfl_ctrl.bits.reset_ovfl_pmds = ovfl_notify ? 0 : 1;
5384 /*
5385 * if needed, we reset all overflowed pmds
5386 */
5387 if (ovfl_notify == 0) reset_pmds = ovfl_pmds;
5388 }
5389
5390 DPRINT_ovfl(("ovfl_pmds=0x%lx reset_pmds=0x%lx\n", ovfl_pmds, reset_pmds));
5391
5392 /*
5393 * reset the requested PMD registers using the short reset values
5394 */
5395 if (reset_pmds) {
5396 unsigned long bm = reset_pmds;
5397 pfm_reset_regs(ctx, &bm, PFM_PMD_SHORT_RESET);
5398 }
5399
5400 if (ovfl_notify && ovfl_ctrl.bits.notify_user) {
5401 /*
5402 * keep track of what to reset when unblocking
5403 */
5404 ctx->ctx_ovfl_regs[0] = ovfl_pmds;
5405
5406 /*
5407 * check for blocking context
5408 */
5409 if (CTX_OVFL_NOBLOCK(ctx) == 0 && ovfl_ctrl.bits.block_task) {
5410
5411 ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_BLOCK;
5412
5413 /*
5414 * set the perfmon specific checking pending work for the task
5415 */
5416 PFM_SET_WORK_PENDING(task, 1);
5417
5418 /*
5419 * when coming from ctxsw, current still points to the
5420 * previous task, therefore we must work with task and not current.
5421 */
5422 set_notify_resume(task);
5423 }
5424 /*
5425 * defer until state is changed (shorten spin window). the context is locked
5426 * anyway, so the signal receiver would come spin for nothing.
5427 */
5428 must_notify = 1;
5429 }
5430
5431 DPRINT_ovfl(("owner [%d] pending=%ld reason=%u ovfl_pmds=0x%lx ovfl_notify=0x%lx masked=%d\n",
5432 GET_PMU_OWNER() ? task_pid_nr(GET_PMU_OWNER()) : -1,
5433 PFM_GET_WORK_PENDING(task),
5434 ctx->ctx_fl_trap_reason,
5435 ovfl_pmds,
5436 ovfl_notify,
5437 ovfl_ctrl.bits.mask_monitoring ? 1 : 0));
5438 /*
5439 * in case monitoring must be stopped, we toggle the psr bits
5440 */
5441 if (ovfl_ctrl.bits.mask_monitoring) {
5442 pfm_mask_monitoring(task);
5443 ctx->ctx_state = PFM_CTX_MASKED;
5444 ctx->ctx_fl_can_restart = 1;
5445 }
5446
5447 /*
5448 * send notification now
5449 */
5450 if (must_notify) pfm_ovfl_notify_user(ctx, ovfl_notify);
5451
5452 return;
5453
5454 sanity_check:
5455 printk(KERN_ERR "perfmon: CPU%d overflow handler [%d] pmc0=0x%lx\n",
5456 smp_processor_id(),
5457 task ? task_pid_nr(task) : -1,
5458 pmc0);
5459 return;
5460
5461 stop_monitoring:
5462 /*
5463 * in SMP, zombie context is never restored but reclaimed in pfm_load_regs().
5464 * Moreover, zombies are also reclaimed in pfm_save_regs(). Therefore we can
5465 * come here as zombie only if the task is the current task. In which case, we
5466 * can access the PMU hardware directly.
5467 *
5468 * Note that zombies do have PM_VALID set. So here we do the minimal.
5469 *
5470 * In case the context was zombified it could not be reclaimed at the time
5471 * the monitoring program exited. At this point, the PMU reservation has been
5472 * returned, the sampiing buffer has been freed. We must convert this call
5473 * into a spurious interrupt. However, we must also avoid infinite overflows
5474 * by stopping monitoring for this task. We can only come here for a per-task
5475 * context. All we need to do is to stop monitoring using the psr bits which
5476 * are always task private. By re-enabling secure montioring, we ensure that
5477 * the monitored task will not be able to re-activate monitoring.
5478 * The task will eventually be context switched out, at which point the context
5479 * will be reclaimed (that includes releasing ownership of the PMU).
5480 *
5481 * So there might be a window of time where the number of per-task session is zero
5482 * yet one PMU might have a owner and get at most one overflow interrupt for a zombie
5483 * context. This is safe because if a per-task session comes in, it will push this one
5484 * out and by the virtue on pfm_save_regs(), this one will disappear. If a system wide
5485 * session is force on that CPU, given that we use task pinning, pfm_save_regs() will
5486 * also push our zombie context out.
5487 *
5488 * Overall pretty hairy stuff....
5489 */
5490 DPRINT(("ctx is zombie for [%d], converted to spurious\n", task ? task_pid_nr(task): -1));
5491 pfm_clear_psr_up();
5492 ia64_psr(regs)->up = 0;
5493 ia64_psr(regs)->sp = 1;
5494 return;
5495 }
5496
5497 static int
5498 pfm_do_interrupt_handler(void *arg, struct pt_regs *regs)
5499 {
5500 struct task_struct *task;
5501 pfm_context_t *ctx;
5502 unsigned long flags;
5503 u64 pmc0;
5504 int this_cpu = smp_processor_id();
5505 int retval = 0;
5506
5507 pfm_stats[this_cpu].pfm_ovfl_intr_count++;
5508
5509 /*
5510 * srlz.d done before arriving here
5511 */
5512 pmc0 = ia64_get_pmc(0);
5513
5514 task = GET_PMU_OWNER();
5515 ctx = GET_PMU_CTX();
5516
5517 /*
5518 * if we have some pending bits set
5519 * assumes : if any PMC0.bit[63-1] is set, then PMC0.fr = 1
5520 */
5521 if (PMC0_HAS_OVFL(pmc0) && task) {
5522 /*
5523 * we assume that pmc0.fr is always set here
5524 */
5525
5526 /* sanity check */
5527 if (!ctx) goto report_spurious1;
5528
5529 if (ctx->ctx_fl_system == 0 && (task->thread.flags & IA64_THREAD_PM_VALID) == 0)
5530 goto report_spurious2;
5531
5532 PROTECT_CTX_NOPRINT(ctx, flags);
5533
5534 pfm_overflow_handler(task, ctx, pmc0, regs);
5535
5536 UNPROTECT_CTX_NOPRINT(ctx, flags);
5537
5538 } else {
5539 pfm_stats[this_cpu].pfm_spurious_ovfl_intr_count++;
5540 retval = -1;
5541 }
5542 /*
5543 * keep it unfrozen at all times
5544 */
5545 pfm_unfreeze_pmu();
5546
5547 return retval;
5548
5549 report_spurious1:
5550 printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d has no PFM context\n",
5551 this_cpu, task_pid_nr(task));
5552 pfm_unfreeze_pmu();
5553 return -1;
5554 report_spurious2:
5555 printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d, invalid flag\n",
5556 this_cpu,
5557 task_pid_nr(task));
5558 pfm_unfreeze_pmu();
5559 return -1;
5560 }
5561
5562 static irqreturn_t
5563 pfm_interrupt_handler(int irq, void *arg)
5564 {
5565 unsigned long start_cycles, total_cycles;
5566 unsigned long min, max;
5567 int this_cpu;
5568 int ret;
5569 struct pt_regs *regs = get_irq_regs();
5570
5571 this_cpu = get_cpu();
5572 if (likely(!pfm_alt_intr_handler)) {
5573 min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min;
5574 max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max;
5575
5576 start_cycles = ia64_get_itc();
5577
5578 ret = pfm_do_interrupt_handler(arg, regs);
5579
5580 total_cycles = ia64_get_itc();
5581
5582 /*
5583 * don't measure spurious interrupts
5584 */
5585 if (likely(ret == 0)) {
5586 total_cycles -= start_cycles;
5587
5588 if (total_cycles < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = total_cycles;
5589 if (total_cycles > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = total_cycles;
5590
5591 pfm_stats[this_cpu].pfm_ovfl_intr_cycles += total_cycles;
5592 }
5593 }
5594 else {
5595 (*pfm_alt_intr_handler->handler)(irq, arg, regs);
5596 }
5597
5598 put_cpu();
5599 return IRQ_HANDLED;
5600 }
5601
5602 /*
5603 * /proc/perfmon interface, for debug only
5604 */
5605
5606 #define PFM_PROC_SHOW_HEADER ((void *)(long)nr_cpu_ids+1)
5607
5608 static void *
5609 pfm_proc_start(struct seq_file *m, loff_t *pos)
5610 {
5611 if (*pos == 0) {
5612 return PFM_PROC_SHOW_HEADER;
5613 }
5614
5615 while (*pos <= nr_cpu_ids) {
5616 if (cpu_online(*pos - 1)) {
5617 return (void *)*pos;
5618 }
5619 ++*pos;
5620 }
5621 return NULL;
5622 }
5623
5624 static void *
5625 pfm_proc_next(struct seq_file *m, void *v, loff_t *pos)
5626 {
5627 ++*pos;
5628 return pfm_proc_start(m, pos);
5629 }
5630
5631 static void
5632 pfm_proc_stop(struct seq_file *m, void *v)
5633 {
5634 }
5635
5636 static void
5637 pfm_proc_show_header(struct seq_file *m)
5638 {
5639 struct list_head * pos;
5640 pfm_buffer_fmt_t * entry;
5641 unsigned long flags;
5642
5643 seq_printf(m,
5644 "perfmon version : %u.%u\n"
5645 "model : %s\n"
5646 "fastctxsw : %s\n"
5647 "expert mode : %s\n"
5648 "ovfl_mask : 0x%lx\n"
5649 "PMU flags : 0x%x\n",
5650 PFM_VERSION_MAJ, PFM_VERSION_MIN,
5651 pmu_conf->pmu_name,
5652 pfm_sysctl.fastctxsw > 0 ? "Yes": "No",
5653 pfm_sysctl.expert_mode > 0 ? "Yes": "No",
5654 pmu_conf->ovfl_val,
5655 pmu_conf->flags);
5656
5657 LOCK_PFS(flags);
5658
5659 seq_printf(m,
5660 "proc_sessions : %u\n"
5661 "sys_sessions : %u\n"
5662 "sys_use_dbregs : %u\n"
5663 "ptrace_use_dbregs : %u\n",
5664 pfm_sessions.pfs_task_sessions,
5665 pfm_sessions.pfs_sys_sessions,
5666 pfm_sessions.pfs_sys_use_dbregs,
5667 pfm_sessions.pfs_ptrace_use_dbregs);
5668
5669 UNLOCK_PFS(flags);
5670
5671 spin_lock(&pfm_buffer_fmt_lock);
5672
5673 list_for_each(pos, &pfm_buffer_fmt_list) {
5674 entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list);
5675 seq_printf(m, "format : %02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x %s\n",
5676 entry->fmt_uuid[0],
5677 entry->fmt_uuid[1],
5678 entry->fmt_uuid[2],
5679 entry->fmt_uuid[3],
5680 entry->fmt_uuid[4],
5681 entry->fmt_uuid[5],
5682 entry->fmt_uuid[6],
5683 entry->fmt_uuid[7],
5684 entry->fmt_uuid[8],
5685 entry->fmt_uuid[9],
5686 entry->fmt_uuid[10],
5687 entry->fmt_uuid[11],
5688 entry->fmt_uuid[12],
5689 entry->fmt_uuid[13],
5690 entry->fmt_uuid[14],
5691 entry->fmt_uuid[15],
5692 entry->fmt_name);
5693 }
5694 spin_unlock(&pfm_buffer_fmt_lock);
5695
5696 }
5697
5698 static int
5699 pfm_proc_show(struct seq_file *m, void *v)
5700 {
5701 unsigned long psr;
5702 unsigned int i;
5703 int cpu;
5704
5705 if (v == PFM_PROC_SHOW_HEADER) {
5706 pfm_proc_show_header(m);
5707 return 0;
5708 }
5709
5710 /* show info for CPU (v - 1) */
5711
5712 cpu = (long)v - 1;
5713 seq_printf(m,
5714 "CPU%-2d overflow intrs : %lu\n"
5715 "CPU%-2d overflow cycles : %lu\n"
5716 "CPU%-2d overflow min : %lu\n"
5717 "CPU%-2d overflow max : %lu\n"
5718 "CPU%-2d smpl handler calls : %lu\n"
5719 "CPU%-2d smpl handler cycles : %lu\n"
5720 "CPU%-2d spurious intrs : %lu\n"
5721 "CPU%-2d replay intrs : %lu\n"
5722 "CPU%-2d syst_wide : %d\n"
5723 "CPU%-2d dcr_pp : %d\n"
5724 "CPU%-2d exclude idle : %d\n"
5725 "CPU%-2d owner : %d\n"
5726 "CPU%-2d context : %p\n"
5727 "CPU%-2d activations : %lu\n",
5728 cpu, pfm_stats[cpu].pfm_ovfl_intr_count,
5729 cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles,
5730 cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_min,
5731 cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_max,
5732 cpu, pfm_stats[cpu].pfm_smpl_handler_calls,
5733 cpu, pfm_stats[cpu].pfm_smpl_handler_cycles,
5734 cpu, pfm_stats[cpu].pfm_spurious_ovfl_intr_count,
5735 cpu, pfm_stats[cpu].pfm_replay_ovfl_intr_count,
5736 cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_SYST_WIDE ? 1 : 0,
5737 cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_DCR_PP ? 1 : 0,
5738 cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_EXCL_IDLE ? 1 : 0,
5739 cpu, pfm_get_cpu_data(pmu_owner, cpu) ? pfm_get_cpu_data(pmu_owner, cpu)->pid: -1,
5740 cpu, pfm_get_cpu_data(pmu_ctx, cpu),
5741 cpu, pfm_get_cpu_data(pmu_activation_number, cpu));
5742
5743 if (num_online_cpus() == 1 && pfm_sysctl.debug > 0) {
5744
5745 psr = pfm_get_psr();
5746
5747 ia64_srlz_d();
5748
5749 seq_printf(m,
5750 "CPU%-2d psr : 0x%lx\n"
5751 "CPU%-2d pmc0 : 0x%lx\n",
5752 cpu, psr,
5753 cpu, ia64_get_pmc(0));
5754
5755 for (i=0; PMC_IS_LAST(i) == 0; i++) {
5756 if (PMC_IS_COUNTING(i) == 0) continue;
5757 seq_printf(m,
5758 "CPU%-2d pmc%u : 0x%lx\n"
5759 "CPU%-2d pmd%u : 0x%lx\n",
5760 cpu, i, ia64_get_pmc(i),
5761 cpu, i, ia64_get_pmd(i));
5762 }
5763 }
5764 return 0;
5765 }
5766
5767 const struct seq_operations pfm_seq_ops = {
5768 .start = pfm_proc_start,
5769 .next = pfm_proc_next,
5770 .stop = pfm_proc_stop,
5771 .show = pfm_proc_show
5772 };
5773
5774 static int
5775 pfm_proc_open(struct inode *inode, struct file *file)
5776 {
5777 return seq_open(file, &pfm_seq_ops);
5778 }
5779
5780
5781 /*
5782 * we come here as soon as local_cpu_data->pfm_syst_wide is set. this happens
5783 * during pfm_enable() hence before pfm_start(). We cannot assume monitoring
5784 * is active or inactive based on mode. We must rely on the value in
5785 * local_cpu_data->pfm_syst_info
5786 */
5787 void
5788 pfm_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin)
5789 {
5790 struct pt_regs *regs;
5791 unsigned long dcr;
5792 unsigned long dcr_pp;
5793
5794 dcr_pp = info & PFM_CPUINFO_DCR_PP ? 1 : 0;
5795
5796 /*
5797 * pid 0 is guaranteed to be the idle task. There is one such task with pid 0
5798 * on every CPU, so we can rely on the pid to identify the idle task.
5799 */
5800 if ((info & PFM_CPUINFO_EXCL_IDLE) == 0 || task->pid) {
5801 regs = task_pt_regs(task);
5802 ia64_psr(regs)->pp = is_ctxswin ? dcr_pp : 0;
5803 return;
5804 }
5805 /*
5806 * if monitoring has started
5807 */
5808 if (dcr_pp) {
5809 dcr = ia64_getreg(_IA64_REG_CR_DCR);
5810 /*
5811 * context switching in?
5812 */
5813 if (is_ctxswin) {
5814 /* mask monitoring for the idle task */
5815 ia64_setreg(_IA64_REG_CR_DCR, dcr & ~IA64_DCR_PP);
5816 pfm_clear_psr_pp();
5817 ia64_srlz_i();
5818 return;
5819 }
5820 /*
5821 * context switching out
5822 * restore monitoring for next task
5823 *
5824 * Due to inlining this odd if-then-else construction generates
5825 * better code.
5826 */
5827 ia64_setreg(_IA64_REG_CR_DCR, dcr |IA64_DCR_PP);
5828 pfm_set_psr_pp();
5829 ia64_srlz_i();
5830 }
5831 }
5832
5833 #ifdef CONFIG_SMP
5834
5835 static void
5836 pfm_force_cleanup(pfm_context_t *ctx, struct pt_regs *regs)
5837 {
5838 struct task_struct *task = ctx->ctx_task;
5839
5840 ia64_psr(regs)->up = 0;
5841 ia64_psr(regs)->sp = 1;
5842
5843 if (GET_PMU_OWNER() == task) {
5844 DPRINT(("cleared ownership for [%d]\n",
5845 task_pid_nr(ctx->ctx_task)));
5846 SET_PMU_OWNER(NULL, NULL);
5847 }
5848
5849 /*
5850 * disconnect the task from the context and vice-versa
5851 */
5852 PFM_SET_WORK_PENDING(task, 0);
5853
5854 task->thread.pfm_context = NULL;
5855 task->thread.flags &= ~IA64_THREAD_PM_VALID;
5856
5857 DPRINT(("force cleanup for [%d]\n", task_pid_nr(task)));
5858 }
5859
5860
5861 /*
5862 * in 2.6, interrupts are masked when we come here and the runqueue lock is held
5863 */
5864 void
5865 pfm_save_regs(struct task_struct *task)
5866 {
5867 pfm_context_t *ctx;
5868 unsigned long flags;
5869 u64 psr;
5870
5871
5872 ctx = PFM_GET_CTX(task);
5873 if (ctx == NULL) return;
5874
5875 /*
5876 * we always come here with interrupts ALREADY disabled by
5877 * the scheduler. So we simply need to protect against concurrent
5878 * access, not CPU concurrency.
5879 */
5880 flags = pfm_protect_ctx_ctxsw(ctx);
5881
5882 if (ctx->ctx_state == PFM_CTX_ZOMBIE) {
5883 struct pt_regs *regs = task_pt_regs(task);
5884
5885 pfm_clear_psr_up();
5886
5887 pfm_force_cleanup(ctx, regs);
5888
5889 BUG_ON(ctx->ctx_smpl_hdr);
5890
5891 pfm_unprotect_ctx_ctxsw(ctx, flags);
5892
5893 pfm_context_free(ctx);
5894 return;
5895 }
5896
5897 /*
5898 * save current PSR: needed because we modify it
5899 */
5900 ia64_srlz_d();
5901 psr = pfm_get_psr();
5902
5903 BUG_ON(psr & (IA64_PSR_I));
5904
5905 /*
5906 * stop monitoring:
5907 * This is the last instruction which may generate an overflow
5908 *
5909 * We do not need to set psr.sp because, it is irrelevant in kernel.
5910 * It will be restored from ipsr when going back to user level
5911 */
5912 pfm_clear_psr_up();
5913
5914 /*
5915 * keep a copy of psr.up (for reload)
5916 */
5917 ctx->ctx_saved_psr_up = psr & IA64_PSR_UP;
5918
5919 /*
5920 * release ownership of this PMU.
5921 * PM interrupts are masked, so nothing
5922 * can happen.
5923 */
5924 SET_PMU_OWNER(NULL, NULL);
5925
5926 /*
5927 * we systematically save the PMD as we have no
5928 * guarantee we will be schedule at that same
5929 * CPU again.
5930 */
5931 pfm_save_pmds(ctx->th_pmds, ctx->ctx_used_pmds[0]);
5932
5933 /*
5934 * save pmc0 ia64_srlz_d() done in pfm_save_pmds()
5935 * we will need it on the restore path to check
5936 * for pending overflow.
5937 */
5938 ctx->th_pmcs[0] = ia64_get_pmc(0);
5939
5940 /*
5941 * unfreeze PMU if had pending overflows
5942 */
5943 if (ctx->th_pmcs[0] & ~0x1UL) pfm_unfreeze_pmu();
5944
5945 /*
5946 * finally, allow context access.
5947 * interrupts will still be masked after this call.
5948 */
5949 pfm_unprotect_ctx_ctxsw(ctx, flags);
5950 }
5951
5952 #else /* !CONFIG_SMP */
5953 void
5954 pfm_save_regs(struct task_struct *task)
5955 {
5956 pfm_context_t *ctx;
5957 u64 psr;
5958
5959 ctx = PFM_GET_CTX(task);
5960 if (ctx == NULL) return;
5961
5962 /*
5963 * save current PSR: needed because we modify it
5964 */
5965 psr = pfm_get_psr();
5966
5967 BUG_ON(psr & (IA64_PSR_I));
5968
5969 /*
5970 * stop monitoring:
5971 * This is the last instruction which may generate an overflow
5972 *
5973 * We do not need to set psr.sp because, it is irrelevant in kernel.
5974 * It will be restored from ipsr when going back to user level
5975 */
5976 pfm_clear_psr_up();
5977
5978 /*
5979 * keep a copy of psr.up (for reload)
5980 */
5981 ctx->ctx_saved_psr_up = psr & IA64_PSR_UP;
5982 }
5983
5984 static void
5985 pfm_lazy_save_regs (struct task_struct *task)
5986 {
5987 pfm_context_t *ctx;
5988 unsigned long flags;
5989
5990 { u64 psr = pfm_get_psr();
5991 BUG_ON(psr & IA64_PSR_UP);
5992 }
5993
5994 ctx = PFM_GET_CTX(task);
5995
5996 /*
5997 * we need to mask PMU overflow here to
5998 * make sure that we maintain pmc0 until
5999 * we save it. overflow interrupts are
6000 * treated as spurious if there is no
6001 * owner.
6002 *
6003 * XXX: I don't think this is necessary
6004 */
6005 PROTECT_CTX(ctx,flags);
6006
6007 /*
6008 * release ownership of this PMU.
6009 * must be done before we save the registers.
6010 *
6011 * after this call any PMU interrupt is treated
6012 * as spurious.
6013 */
6014 SET_PMU_OWNER(NULL, NULL);
6015
6016 /*
6017 * save all the pmds we use
6018 */
6019 pfm_save_pmds(ctx->th_pmds, ctx->ctx_used_pmds[0]);
6020
6021 /*
6022 * save pmc0 ia64_srlz_d() done in pfm_save_pmds()
6023 * it is needed to check for pended overflow
6024 * on the restore path
6025 */
6026 ctx->th_pmcs[0] = ia64_get_pmc(0);
6027
6028 /*
6029 * unfreeze PMU if had pending overflows
6030 */
6031 if (ctx->th_pmcs[0] & ~0x1UL) pfm_unfreeze_pmu();
6032
6033 /*
6034 * now get can unmask PMU interrupts, they will
6035 * be treated as purely spurious and we will not
6036 * lose any information
6037 */
6038 UNPROTECT_CTX(ctx,flags);
6039 }
6040 #endif /* CONFIG_SMP */
6041
6042 #ifdef CONFIG_SMP
6043 /*
6044 * in 2.6, interrupts are masked when we come here and the runqueue lock is held
6045 */
6046 void
6047 pfm_load_regs (struct task_struct *task)
6048 {
6049 pfm_context_t *ctx;
6050 unsigned long pmc_mask = 0UL, pmd_mask = 0UL;
6051 unsigned long flags;
6052 u64 psr, psr_up;
6053 int need_irq_resend;
6054
6055 ctx = PFM_GET_CTX(task);
6056 if (unlikely(ctx == NULL)) return;
6057
6058 BUG_ON(GET_PMU_OWNER());
6059
6060 /*
6061 * possible on unload
6062 */
6063 if (unlikely((task->thread.flags & IA64_THREAD_PM_VALID) == 0)) return;
6064
6065 /*
6066 * we always come here with interrupts ALREADY disabled by
6067 * the scheduler. So we simply need to protect against concurrent
6068 * access, not CPU concurrency.
6069 */
6070 flags = pfm_protect_ctx_ctxsw(ctx);
6071 psr = pfm_get_psr();
6072
6073 need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND;
6074
6075 BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
6076 BUG_ON(psr & IA64_PSR_I);
6077
6078 if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) {
6079 struct pt_regs *regs = task_pt_regs(task);
6080
6081 BUG_ON(ctx->ctx_smpl_hdr);
6082
6083 pfm_force_cleanup(ctx, regs);
6084
6085 pfm_unprotect_ctx_ctxsw(ctx, flags);
6086
6087 /*
6088 * this one (kmalloc'ed) is fine with interrupts disabled
6089 */
6090 pfm_context_free(ctx);
6091
6092 return;
6093 }
6094
6095 /*
6096 * we restore ALL the debug registers to avoid picking up
6097 * stale state.
6098 */
6099 if (ctx->ctx_fl_using_dbreg) {
6100 pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
6101 pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
6102 }
6103 /*
6104 * retrieve saved psr.up
6105 */
6106 psr_up = ctx->ctx_saved_psr_up;
6107
6108 /*
6109 * if we were the last user of the PMU on that CPU,
6110 * then nothing to do except restore psr
6111 */
6112 if (GET_LAST_CPU(ctx) == smp_processor_id() && ctx->ctx_last_activation == GET_ACTIVATION()) {
6113
6114 /*
6115 * retrieve partial reload masks (due to user modifications)
6116 */
6117 pmc_mask = ctx->ctx_reload_pmcs[0];
6118 pmd_mask = ctx->ctx_reload_pmds[0];
6119
6120 } else {
6121 /*
6122 * To avoid leaking information to the user level when psr.sp=0,
6123 * we must reload ALL implemented pmds (even the ones we don't use).
6124 * In the kernel we only allow PFM_READ_PMDS on registers which
6125 * we initialized or requested (sampling) so there is no risk there.
6126 */
6127 pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0];
6128
6129 /*
6130 * ALL accessible PMCs are systematically reloaded, unused registers
6131 * get their default (from pfm_reset_pmu_state()) values to avoid picking
6132 * up stale configuration.
6133 *
6134 * PMC0 is never in the mask. It is always restored separately.
6135 */
6136 pmc_mask = ctx->ctx_all_pmcs[0];
6137 }
6138 /*
6139 * when context is MASKED, we will restore PMC with plm=0
6140 * and PMD with stale information, but that's ok, nothing
6141 * will be captured.
6142 *
6143 * XXX: optimize here
6144 */
6145 if (pmd_mask) pfm_restore_pmds(ctx->th_pmds, pmd_mask);
6146 if (pmc_mask) pfm_restore_pmcs(ctx->th_pmcs, pmc_mask);
6147
6148 /*
6149 * check for pending overflow at the time the state
6150 * was saved.
6151 */
6152 if (unlikely(PMC0_HAS_OVFL(ctx->th_pmcs[0]))) {
6153 /*
6154 * reload pmc0 with the overflow information
6155 * On McKinley PMU, this will trigger a PMU interrupt
6156 */
6157 ia64_set_pmc(0, ctx->th_pmcs[0]);
6158 ia64_srlz_d();
6159 ctx->th_pmcs[0] = 0UL;
6160
6161 /*
6162 * will replay the PMU interrupt
6163 */
6164 if (need_irq_resend) ia64_resend_irq(IA64_PERFMON_VECTOR);
6165
6166 pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++;
6167 }
6168
6169 /*
6170 * we just did a reload, so we reset the partial reload fields
6171 */
6172 ctx->ctx_reload_pmcs[0] = 0UL;
6173 ctx->ctx_reload_pmds[0] = 0UL;
6174
6175 SET_LAST_CPU(ctx, smp_processor_id());
6176
6177 /*
6178 * dump activation value for this PMU
6179 */
6180 INC_ACTIVATION();
6181 /*
6182 * record current activation for this context
6183 */
6184 SET_ACTIVATION(ctx);
6185
6186 /*
6187 * establish new ownership.
6188 */
6189 SET_PMU_OWNER(task, ctx);
6190
6191 /*
6192 * restore the psr.up bit. measurement
6193 * is active again.
6194 * no PMU interrupt can happen at this point
6195 * because we still have interrupts disabled.
6196 */
6197 if (likely(psr_up)) pfm_set_psr_up();
6198
6199 /*
6200 * allow concurrent access to context
6201 */
6202 pfm_unprotect_ctx_ctxsw(ctx, flags);
6203 }
6204 #else /* !CONFIG_SMP */
6205 /*
6206 * reload PMU state for UP kernels
6207 * in 2.5 we come here with interrupts disabled
6208 */
6209 void
6210 pfm_load_regs (struct task_struct *task)
6211 {
6212 pfm_context_t *ctx;
6213 struct task_struct *owner;
6214 unsigned long pmd_mask, pmc_mask;
6215 u64 psr, psr_up;
6216 int need_irq_resend;
6217
6218 owner = GET_PMU_OWNER();
6219 ctx = PFM_GET_CTX(task);
6220 psr = pfm_get_psr();
6221
6222 BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
6223 BUG_ON(psr & IA64_PSR_I);
6224
6225 /*
6226 * we restore ALL the debug registers to avoid picking up
6227 * stale state.
6228 *
6229 * This must be done even when the task is still the owner
6230 * as the registers may have been modified via ptrace()
6231 * (not perfmon) by the previous task.
6232 */
6233 if (ctx->ctx_fl_using_dbreg) {
6234 pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
6235 pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
6236 }
6237
6238 /*
6239 * retrieved saved psr.up
6240 */
6241 psr_up = ctx->ctx_saved_psr_up;
6242 need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND;
6243
6244 /*
6245 * short path, our state is still there, just
6246 * need to restore psr and we go
6247 *
6248 * we do not touch either PMC nor PMD. the psr is not touched
6249 * by the overflow_handler. So we are safe w.r.t. to interrupt
6250 * concurrency even without interrupt masking.
6251 */
6252 if (likely(owner == task)) {
6253 if (likely(psr_up)) pfm_set_psr_up();
6254 return;
6255 }
6256
6257 /*
6258 * someone else is still using the PMU, first push it out and
6259 * then we'll be able to install our stuff !
6260 *
6261 * Upon return, there will be no owner for the current PMU
6262 */
6263 if (owner) pfm_lazy_save_regs(owner);
6264
6265 /*
6266 * To avoid leaking information to the user level when psr.sp=0,
6267 * we must reload ALL implemented pmds (even the ones we don't use).
6268 * In the kernel we only allow PFM_READ_PMDS on registers which
6269 * we initialized or requested (sampling) so there is no risk there.
6270 */
6271 pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0];
6272
6273 /*
6274 * ALL accessible PMCs are systematically reloaded, unused registers
6275 * get their default (from pfm_reset_pmu_state()) values to avoid picking
6276 * up stale configuration.
6277 *
6278 * PMC0 is never in the mask. It is always restored separately
6279 */
6280 pmc_mask = ctx->ctx_all_pmcs[0];
6281
6282 pfm_restore_pmds(ctx->th_pmds, pmd_mask);
6283 pfm_restore_pmcs(ctx->th_pmcs, pmc_mask);
6284
6285 /*
6286 * check for pending overflow at the time the state
6287 * was saved.
6288 */
6289 if (unlikely(PMC0_HAS_OVFL(ctx->th_pmcs[0]))) {
6290 /*
6291 * reload pmc0 with the overflow information
6292 * On McKinley PMU, this will trigger a PMU interrupt
6293 */
6294 ia64_set_pmc(0, ctx->th_pmcs[0]);
6295 ia64_srlz_d();
6296
6297 ctx->th_pmcs[0] = 0UL;
6298
6299 /*
6300 * will replay the PMU interrupt
6301 */
6302 if (need_irq_resend) ia64_resend_irq(IA64_PERFMON_VECTOR);
6303
6304 pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++;
6305 }
6306
6307 /*
6308 * establish new ownership.
6309 */
6310 SET_PMU_OWNER(task, ctx);
6311
6312 /*
6313 * restore the psr.up bit. measurement
6314 * is active again.
6315 * no PMU interrupt can happen at this point
6316 * because we still have interrupts disabled.
6317 */
6318 if (likely(psr_up)) pfm_set_psr_up();
6319 }
6320 #endif /* CONFIG_SMP */
6321
6322 /*
6323 * this function assumes monitoring is stopped
6324 */
6325 static void
6326 pfm_flush_pmds(struct task_struct *task, pfm_context_t *ctx)
6327 {
6328 u64 pmc0;
6329 unsigned long mask2, val, pmd_val, ovfl_val;
6330 int i, can_access_pmu = 0;
6331 int is_self;
6332
6333 /*
6334 * is the caller the task being monitored (or which initiated the
6335 * session for system wide measurements)
6336 */
6337 is_self = ctx->ctx_task == task ? 1 : 0;
6338
6339 /*
6340 * can access PMU is task is the owner of the PMU state on the current CPU
6341 * or if we are running on the CPU bound to the context in system-wide mode
6342 * (that is not necessarily the task the context is attached to in this mode).
6343 * In system-wide we always have can_access_pmu true because a task running on an
6344 * invalid processor is flagged earlier in the call stack (see pfm_stop).
6345 */
6346 can_access_pmu = (GET_PMU_OWNER() == task) || (ctx->ctx_fl_system && ctx->ctx_cpu == smp_processor_id());
6347 if (can_access_pmu) {
6348 /*
6349 * Mark the PMU as not owned
6350 * This will cause the interrupt handler to do nothing in case an overflow
6351 * interrupt was in-flight
6352 * This also guarantees that pmc0 will contain the final state
6353 * It virtually gives us full control on overflow processing from that point
6354 * on.
6355 */
6356 SET_PMU_OWNER(NULL, NULL);
6357 DPRINT(("releasing ownership\n"));
6358
6359 /*
6360 * read current overflow status:
6361 *
6362 * we are guaranteed to read the final stable state
6363 */
6364 ia64_srlz_d();
6365 pmc0 = ia64_get_pmc(0); /* slow */
6366
6367 /*
6368 * reset freeze bit, overflow status information destroyed
6369 */
6370 pfm_unfreeze_pmu();
6371 } else {
6372 pmc0 = ctx->th_pmcs[0];
6373 /*
6374 * clear whatever overflow status bits there were
6375 */
6376 ctx->th_pmcs[0] = 0;
6377 }
6378 ovfl_val = pmu_conf->ovfl_val;
6379 /*
6380 * we save all the used pmds
6381 * we take care of overflows for counting PMDs
6382 *
6383 * XXX: sampling situation is not taken into account here
6384 */
6385 mask2 = ctx->ctx_used_pmds[0];
6386
6387 DPRINT(("is_self=%d ovfl_val=0x%lx mask2=0x%lx\n", is_self, ovfl_val, mask2));
6388
6389 for (i = 0; mask2; i++, mask2>>=1) {
6390
6391 /* skip non used pmds */
6392 if ((mask2 & 0x1) == 0) continue;
6393
6394 /*
6395 * can access PMU always true in system wide mode
6396 */
6397 val = pmd_val = can_access_pmu ? ia64_get_pmd(i) : ctx->th_pmds[i];
6398
6399 if (PMD_IS_COUNTING(i)) {
6400 DPRINT(("[%d] pmd[%d] ctx_pmd=0x%lx hw_pmd=0x%lx\n",
6401 task_pid_nr(task),
6402 i,
6403 ctx->ctx_pmds[i].val,
6404 val & ovfl_val));
6405
6406 /*
6407 * we rebuild the full 64 bit value of the counter
6408 */
6409 val = ctx->ctx_pmds[i].val + (val & ovfl_val);
6410
6411 /*
6412 * now everything is in ctx_pmds[] and we need
6413 * to clear the saved context from save_regs() such that
6414 * pfm_read_pmds() gets the correct value
6415 */
6416 pmd_val = 0UL;
6417
6418 /*
6419 * take care of overflow inline
6420 */
6421 if (pmc0 & (1UL << i)) {
6422 val += 1 + ovfl_val;
6423 DPRINT(("[%d] pmd[%d] overflowed\n", task_pid_nr(task), i));
6424 }
6425 }
6426
6427 DPRINT(("[%d] ctx_pmd[%d]=0x%lx pmd_val=0x%lx\n", task_pid_nr(task), i, val, pmd_val));
6428
6429 if (is_self) ctx->th_pmds[i] = pmd_val;
6430
6431 ctx->ctx_pmds[i].val = val;
6432 }
6433 }
6434
6435 static struct irqaction perfmon_irqaction = {
6436 .handler = pfm_interrupt_handler,
6437 .flags = IRQF_DISABLED,
6438 .name = "perfmon"
6439 };
6440
6441 static void
6442 pfm_alt_save_pmu_state(void *data)
6443 {
6444 struct pt_regs *regs;
6445
6446 regs = task_pt_regs(current);
6447
6448 DPRINT(("called\n"));
6449
6450 /*
6451 * should not be necessary but
6452 * let's take not risk
6453 */
6454 pfm_clear_psr_up();
6455 pfm_clear_psr_pp();
6456 ia64_psr(regs)->pp = 0;
6457
6458 /*
6459 * This call is required
6460 * May cause a spurious interrupt on some processors
6461 */
6462 pfm_freeze_pmu();
6463
6464 ia64_srlz_d();
6465 }
6466
6467 void
6468 pfm_alt_restore_pmu_state(void *data)
6469 {
6470 struct pt_regs *regs;
6471
6472 regs = task_pt_regs(current);
6473
6474 DPRINT(("called\n"));
6475
6476 /*
6477 * put PMU back in state expected
6478 * by perfmon
6479 */
6480 pfm_clear_psr_up();
6481 pfm_clear_psr_pp();
6482 ia64_psr(regs)->pp = 0;
6483
6484 /*
6485 * perfmon runs with PMU unfrozen at all times
6486 */
6487 pfm_unfreeze_pmu();
6488
6489 ia64_srlz_d();
6490 }
6491
6492 int
6493 pfm_install_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl)
6494 {
6495 int ret, i;
6496 int reserve_cpu;
6497
6498 /* some sanity checks */
6499 if (hdl == NULL || hdl->handler == NULL) return -EINVAL;
6500
6501 /* do the easy test first */
6502 if (pfm_alt_intr_handler) return -EBUSY;
6503
6504 /* one at a time in the install or remove, just fail the others */
6505 if (!spin_trylock(&pfm_alt_install_check)) {
6506 return -EBUSY;
6507 }
6508
6509 /* reserve our session */
6510 for_each_online_cpu(reserve_cpu) {
6511 ret = pfm_reserve_session(NULL, 1, reserve_cpu);
6512 if (ret) goto cleanup_reserve;
6513 }
6514
6515 /* save the current system wide pmu states */
6516 ret = on_each_cpu(pfm_alt_save_pmu_state, NULL, 1);
6517 if (ret) {
6518 DPRINT(("on_each_cpu() failed: %d\n", ret));
6519 goto cleanup_reserve;
6520 }
6521
6522 /* officially change to the alternate interrupt handler */
6523 pfm_alt_intr_handler = hdl;
6524
6525 spin_unlock(&pfm_alt_install_check);
6526
6527 return 0;
6528
6529 cleanup_reserve:
6530 for_each_online_cpu(i) {
6531 /* don't unreserve more than we reserved */
6532 if (i >= reserve_cpu) break;
6533
6534 pfm_unreserve_session(NULL, 1, i);
6535 }
6536
6537 spin_unlock(&pfm_alt_install_check);
6538
6539 return ret;
6540 }
6541 EXPORT_SYMBOL_GPL(pfm_install_alt_pmu_interrupt);
6542
6543 int
6544 pfm_remove_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl)
6545 {
6546 int i;
6547 int ret;
6548
6549 if (hdl == NULL) return -EINVAL;
6550
6551 /* cannot remove someone else's handler! */
6552 if (pfm_alt_intr_handler != hdl) return -EINVAL;
6553
6554 /* one at a time in the install or remove, just fail the others */
6555 if (!spin_trylock(&pfm_alt_install_check)) {
6556 return -EBUSY;
6557 }
6558
6559 pfm_alt_intr_handler = NULL;
6560
6561 ret = on_each_cpu(pfm_alt_restore_pmu_state, NULL, 1);
6562 if (ret) {
6563 DPRINT(("on_each_cpu() failed: %d\n", ret));
6564 }
6565
6566 for_each_online_cpu(i) {
6567 pfm_unreserve_session(NULL, 1, i);
6568 }
6569
6570 spin_unlock(&pfm_alt_install_check);
6571
6572 return 0;
6573 }
6574 EXPORT_SYMBOL_GPL(pfm_remove_alt_pmu_interrupt);
6575
6576 /*
6577 * perfmon initialization routine, called from the initcall() table
6578 */
6579 static int init_pfm_fs(void);
6580
6581 static int __init
6582 pfm_probe_pmu(void)
6583 {
6584 pmu_config_t **p;
6585 int family;
6586
6587 family = local_cpu_data->family;
6588 p = pmu_confs;
6589
6590 while(*p) {
6591 if ((*p)->probe) {
6592 if ((*p)->probe() == 0) goto found;
6593 } else if ((*p)->pmu_family == family || (*p)->pmu_family == 0xff) {
6594 goto found;
6595 }
6596 p++;
6597 }
6598 return -1;
6599 found:
6600 pmu_conf = *p;
6601 return 0;
6602 }
6603
6604 static const struct file_operations pfm_proc_fops = {
6605 .open = pfm_proc_open,
6606 .read = seq_read,
6607 .llseek = seq_lseek,
6608 .release = seq_release,
6609 };
6610
6611 int __init
6612 pfm_init(void)
6613 {
6614 unsigned int n, n_counters, i;
6615
6616 printk("perfmon: version %u.%u IRQ %u\n",
6617 PFM_VERSION_MAJ,
6618 PFM_VERSION_MIN,
6619 IA64_PERFMON_VECTOR);
6620
6621 if (pfm_probe_pmu()) {
6622 printk(KERN_INFO "perfmon: disabled, there is no support for processor family %d\n",
6623 local_cpu_data->family);
6624 return -ENODEV;
6625 }
6626
6627 /*
6628 * compute the number of implemented PMD/PMC from the
6629 * description tables
6630 */
6631 n = 0;
6632 for (i=0; PMC_IS_LAST(i) == 0; i++) {
6633 if (PMC_IS_IMPL(i) == 0) continue;
6634 pmu_conf->impl_pmcs[i>>6] |= 1UL << (i&63);
6635 n++;
6636 }
6637 pmu_conf->num_pmcs = n;
6638
6639 n = 0; n_counters = 0;
6640 for (i=0; PMD_IS_LAST(i) == 0; i++) {
6641 if (PMD_IS_IMPL(i) == 0) continue;
6642 pmu_conf->impl_pmds[i>>6] |= 1UL << (i&63);
6643 n++;
6644 if (PMD_IS_COUNTING(i)) n_counters++;
6645 }
6646 pmu_conf->num_pmds = n;
6647 pmu_conf->num_counters = n_counters;
6648
6649 /*
6650 * sanity checks on the number of debug registers
6651 */
6652 if (pmu_conf->use_rr_dbregs) {
6653 if (pmu_conf->num_ibrs > IA64_NUM_DBG_REGS) {
6654 printk(KERN_INFO "perfmon: unsupported number of code debug registers (%u)\n", pmu_conf->num_ibrs);
6655 pmu_conf = NULL;
6656 return -1;
6657 }
6658 if (pmu_conf->num_dbrs > IA64_NUM_DBG_REGS) {
6659 printk(KERN_INFO "perfmon: unsupported number of data debug registers (%u)\n", pmu_conf->num_ibrs);
6660 pmu_conf = NULL;
6661 return -1;
6662 }
6663 }
6664
6665 printk("perfmon: %s PMU detected, %u PMCs, %u PMDs, %u counters (%lu bits)\n",
6666 pmu_conf->pmu_name,
6667 pmu_conf->num_pmcs,
6668 pmu_conf->num_pmds,
6669 pmu_conf->num_counters,
6670 ffz(pmu_conf->ovfl_val));
6671
6672 /* sanity check */
6673 if (pmu_conf->num_pmds >= PFM_NUM_PMD_REGS || pmu_conf->num_pmcs >= PFM_NUM_PMC_REGS) {
6674 printk(KERN_ERR "perfmon: not enough pmc/pmd, perfmon disabled\n");
6675 pmu_conf = NULL;
6676 return -1;
6677 }
6678
6679 /*
6680 * create /proc/perfmon (mostly for debugging purposes)
6681 */
6682 perfmon_dir = proc_create("perfmon", S_IRUGO, NULL, &pfm_proc_fops);
6683 if (perfmon_dir == NULL) {
6684 printk(KERN_ERR "perfmon: cannot create /proc entry, perfmon disabled\n");
6685 pmu_conf = NULL;
6686 return -1;
6687 }
6688
6689 /*
6690 * create /proc/sys/kernel/perfmon (for debugging purposes)
6691 */
6692 pfm_sysctl_header = register_sysctl_table(pfm_sysctl_root);
6693
6694 /*
6695 * initialize all our spinlocks
6696 */
6697 spin_lock_init(&pfm_sessions.pfs_lock);
6698 spin_lock_init(&pfm_buffer_fmt_lock);
6699
6700 init_pfm_fs();
6701
6702 for(i=0; i < NR_CPUS; i++) pfm_stats[i].pfm_ovfl_intr_cycles_min = ~0UL;
6703
6704 return 0;
6705 }
6706
6707 __initcall(pfm_init);
6708
6709 /*
6710 * this function is called before pfm_init()
6711 */
6712 void
6713 pfm_init_percpu (void)
6714 {
6715 static int first_time=1;
6716 /*
6717 * make sure no measurement is active
6718 * (may inherit programmed PMCs from EFI).
6719 */
6720 pfm_clear_psr_pp();
6721 pfm_clear_psr_up();
6722
6723 /*
6724 * we run with the PMU not frozen at all times
6725 */
6726 pfm_unfreeze_pmu();
6727
6728 if (first_time) {
6729 register_percpu_irq(IA64_PERFMON_VECTOR, &perfmon_irqaction);
6730 first_time=0;
6731 }
6732
6733 ia64_setreg(_IA64_REG_CR_PMV, IA64_PERFMON_VECTOR);
6734 ia64_srlz_d();
6735 }
6736
6737 /*
6738 * used for debug purposes only
6739 */
6740 void
6741 dump_pmu_state(const char *from)
6742 {
6743 struct task_struct *task;
6744 struct pt_regs *regs;
6745 pfm_context_t *ctx;
6746 unsigned long psr, dcr, info, flags;
6747 int i, this_cpu;
6748
6749 local_irq_save(flags);
6750
6751 this_cpu = smp_processor_id();
6752 regs = task_pt_regs(current);
6753 info = PFM_CPUINFO_GET();
6754 dcr = ia64_getreg(_IA64_REG_CR_DCR);
6755
6756 if (info == 0 && ia64_psr(regs)->pp == 0 && (dcr & IA64_DCR_PP) == 0) {
6757 local_irq_restore(flags);
6758 return;
6759 }
6760
6761 printk("CPU%d from %s() current [%d] iip=0x%lx %s\n",
6762 this_cpu,
6763 from,
6764 task_pid_nr(current),
6765 regs->cr_iip,
6766 current->comm);
6767
6768 task = GET_PMU_OWNER();
6769 ctx = GET_PMU_CTX();
6770
6771 printk("->CPU%d owner [%d] ctx=%p\n", this_cpu, task ? task_pid_nr(task) : -1, ctx);
6772
6773 psr = pfm_get_psr();
6774
6775 printk("->CPU%d pmc0=0x%lx psr.pp=%d psr.up=%d dcr.pp=%d syst_info=0x%lx user_psr.up=%d user_psr.pp=%d\n",
6776 this_cpu,
6777 ia64_get_pmc(0),
6778 psr & IA64_PSR_PP ? 1 : 0,
6779 psr & IA64_PSR_UP ? 1 : 0,
6780 dcr & IA64_DCR_PP ? 1 : 0,
6781 info,
6782 ia64_psr(regs)->up,
6783 ia64_psr(regs)->pp);
6784
6785 ia64_psr(regs)->up = 0;
6786 ia64_psr(regs)->pp = 0;
6787
6788 for (i=1; PMC_IS_LAST(i) == 0; i++) {
6789 if (PMC_IS_IMPL(i) == 0) continue;
6790 printk("->CPU%d pmc[%d]=0x%lx thread_pmc[%d]=0x%lx\n", this_cpu, i, ia64_get_pmc(i), i, ctx->th_pmcs[i]);
6791 }
6792
6793 for (i=1; PMD_IS_LAST(i) == 0; i++) {
6794 if (PMD_IS_IMPL(i) == 0) continue;
6795 printk("->CPU%d pmd[%d]=0x%lx thread_pmd[%d]=0x%lx\n", this_cpu, i, ia64_get_pmd(i), i, ctx->th_pmds[i]);
6796 }
6797
6798 if (ctx) {
6799 printk("->CPU%d ctx_state=%d vaddr=%p addr=%p fd=%d ctx_task=[%d] saved_psr_up=0x%lx\n",
6800 this_cpu,
6801 ctx->ctx_state,
6802 ctx->ctx_smpl_vaddr,
6803 ctx->ctx_smpl_hdr,
6804 ctx->ctx_msgq_head,
6805 ctx->ctx_msgq_tail,
6806 ctx->ctx_saved_psr_up);
6807 }
6808 local_irq_restore(flags);
6809 }
6810
6811 /*
6812 * called from process.c:copy_thread(). task is new child.
6813 */
6814 void
6815 pfm_inherit(struct task_struct *task, struct pt_regs *regs)
6816 {
6817 struct thread_struct *thread;
6818
6819 DPRINT(("perfmon: pfm_inherit clearing state for [%d]\n", task_pid_nr(task)));
6820
6821 thread = &task->thread;
6822
6823 /*
6824 * cut links inherited from parent (current)
6825 */
6826 thread->pfm_context = NULL;
6827
6828 PFM_SET_WORK_PENDING(task, 0);
6829
6830 /*
6831 * the psr bits are already set properly in copy_threads()
6832 */
6833 }
6834 #else /* !CONFIG_PERFMON */
6835 asmlinkage long
6836 sys_perfmonctl (int fd, int cmd, void *arg, int count)
6837 {
6838 return -ENOSYS;
6839 }
6840 #endif /* CONFIG_PERFMON */
Linux with added FPC-III support