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[pohmelfs.git] / arch / x86 / oprofile / nmi_int.c
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1 /**
2 * @file nmi_int.c
4 * @remark Copyright 2002-2009 OProfile authors
5 * @remark Read the file COPYING
7 * @author John Levon <levon@movementarian.org>
8 * @author Robert Richter <robert.richter@amd.com>
9 * @author Barry Kasindorf <barry.kasindorf@amd.com>
10 * @author Jason Yeh <jason.yeh@amd.com>
11 * @author Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
14 #include <linux/init.h>
15 #include <linux/notifier.h>
16 #include <linux/smp.h>
17 #include <linux/oprofile.h>
18 #include <linux/syscore_ops.h>
19 #include <linux/slab.h>
20 #include <linux/moduleparam.h>
21 #include <linux/kdebug.h>
22 #include <linux/cpu.h>
23 #include <asm/nmi.h>
24 #include <asm/msr.h>
25 #include <asm/apic.h>
27 #include "op_counter.h"
28 #include "op_x86_model.h"
30 static struct op_x86_model_spec *model;
31 static DEFINE_PER_CPU(struct op_msrs, cpu_msrs);
32 static DEFINE_PER_CPU(unsigned long, saved_lvtpc);
34 /* must be protected with get_online_cpus()/put_online_cpus(): */
35 static int nmi_enabled;
36 static int ctr_running;
38 struct op_counter_config counter_config[OP_MAX_COUNTER];
40 /* common functions */
42 u64 op_x86_get_ctrl(struct op_x86_model_spec const *model,
43 struct op_counter_config *counter_config)
45 u64 val = 0;
46 u16 event = (u16)counter_config->event;
48 val |= ARCH_PERFMON_EVENTSEL_INT;
49 val |= counter_config->user ? ARCH_PERFMON_EVENTSEL_USR : 0;
50 val |= counter_config->kernel ? ARCH_PERFMON_EVENTSEL_OS : 0;
51 val |= (counter_config->unit_mask & 0xFF) << 8;
52 counter_config->extra &= (ARCH_PERFMON_EVENTSEL_INV |
53 ARCH_PERFMON_EVENTSEL_EDGE |
54 ARCH_PERFMON_EVENTSEL_CMASK);
55 val |= counter_config->extra;
56 event &= model->event_mask ? model->event_mask : 0xFF;
57 val |= event & 0xFF;
58 val |= (event & 0x0F00) << 24;
60 return val;
64 static int profile_exceptions_notify(unsigned int val, struct pt_regs *regs)
66 if (ctr_running)
67 model->check_ctrs(regs, &__get_cpu_var(cpu_msrs));
68 else if (!nmi_enabled)
69 return NMI_DONE;
70 else
71 model->stop(&__get_cpu_var(cpu_msrs));
72 return NMI_HANDLED;
75 static void nmi_cpu_save_registers(struct op_msrs *msrs)
77 struct op_msr *counters = msrs->counters;
78 struct op_msr *controls = msrs->controls;
79 unsigned int i;
81 for (i = 0; i < model->num_counters; ++i) {
82 if (counters[i].addr)
83 rdmsrl(counters[i].addr, counters[i].saved);
86 for (i = 0; i < model->num_controls; ++i) {
87 if (controls[i].addr)
88 rdmsrl(controls[i].addr, controls[i].saved);
92 static void nmi_cpu_start(void *dummy)
94 struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
95 if (!msrs->controls)
96 WARN_ON_ONCE(1);
97 else
98 model->start(msrs);
101 static int nmi_start(void)
103 get_online_cpus();
104 ctr_running = 1;
105 /* make ctr_running visible to the nmi handler: */
106 smp_mb();
107 on_each_cpu(nmi_cpu_start, NULL, 1);
108 put_online_cpus();
109 return 0;
112 static void nmi_cpu_stop(void *dummy)
114 struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
115 if (!msrs->controls)
116 WARN_ON_ONCE(1);
117 else
118 model->stop(msrs);
121 static void nmi_stop(void)
123 get_online_cpus();
124 on_each_cpu(nmi_cpu_stop, NULL, 1);
125 ctr_running = 0;
126 put_online_cpus();
129 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
131 static DEFINE_PER_CPU(int, switch_index);
133 static inline int has_mux(void)
135 return !!model->switch_ctrl;
138 inline int op_x86_phys_to_virt(int phys)
140 return __this_cpu_read(switch_index) + phys;
143 inline int op_x86_virt_to_phys(int virt)
145 return virt % model->num_counters;
148 static void nmi_shutdown_mux(void)
150 int i;
152 if (!has_mux())
153 return;
155 for_each_possible_cpu(i) {
156 kfree(per_cpu(cpu_msrs, i).multiplex);
157 per_cpu(cpu_msrs, i).multiplex = NULL;
158 per_cpu(switch_index, i) = 0;
162 static int nmi_setup_mux(void)
164 size_t multiplex_size =
165 sizeof(struct op_msr) * model->num_virt_counters;
166 int i;
168 if (!has_mux())
169 return 1;
171 for_each_possible_cpu(i) {
172 per_cpu(cpu_msrs, i).multiplex =
173 kzalloc(multiplex_size, GFP_KERNEL);
174 if (!per_cpu(cpu_msrs, i).multiplex)
175 return 0;
178 return 1;
181 static void nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs)
183 int i;
184 struct op_msr *multiplex = msrs->multiplex;
186 if (!has_mux())
187 return;
189 for (i = 0; i < model->num_virt_counters; ++i) {
190 if (counter_config[i].enabled) {
191 multiplex[i].saved = -(u64)counter_config[i].count;
192 } else {
193 multiplex[i].saved = 0;
197 per_cpu(switch_index, cpu) = 0;
200 static void nmi_cpu_save_mpx_registers(struct op_msrs *msrs)
202 struct op_msr *counters = msrs->counters;
203 struct op_msr *multiplex = msrs->multiplex;
204 int i;
206 for (i = 0; i < model->num_counters; ++i) {
207 int virt = op_x86_phys_to_virt(i);
208 if (counters[i].addr)
209 rdmsrl(counters[i].addr, multiplex[virt].saved);
213 static void nmi_cpu_restore_mpx_registers(struct op_msrs *msrs)
215 struct op_msr *counters = msrs->counters;
216 struct op_msr *multiplex = msrs->multiplex;
217 int i;
219 for (i = 0; i < model->num_counters; ++i) {
220 int virt = op_x86_phys_to_virt(i);
221 if (counters[i].addr)
222 wrmsrl(counters[i].addr, multiplex[virt].saved);
226 static void nmi_cpu_switch(void *dummy)
228 int cpu = smp_processor_id();
229 int si = per_cpu(switch_index, cpu);
230 struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
232 nmi_cpu_stop(NULL);
233 nmi_cpu_save_mpx_registers(msrs);
235 /* move to next set */
236 si += model->num_counters;
237 if ((si >= model->num_virt_counters) || (counter_config[si].count == 0))
238 per_cpu(switch_index, cpu) = 0;
239 else
240 per_cpu(switch_index, cpu) = si;
242 model->switch_ctrl(model, msrs);
243 nmi_cpu_restore_mpx_registers(msrs);
245 nmi_cpu_start(NULL);
250 * Quick check to see if multiplexing is necessary.
251 * The check should be sufficient since counters are used
252 * in ordre.
254 static int nmi_multiplex_on(void)
256 return counter_config[model->num_counters].count ? 0 : -EINVAL;
259 static int nmi_switch_event(void)
261 if (!has_mux())
262 return -ENOSYS; /* not implemented */
263 if (nmi_multiplex_on() < 0)
264 return -EINVAL; /* not necessary */
266 get_online_cpus();
267 if (ctr_running)
268 on_each_cpu(nmi_cpu_switch, NULL, 1);
269 put_online_cpus();
271 return 0;
274 static inline void mux_init(struct oprofile_operations *ops)
276 if (has_mux())
277 ops->switch_events = nmi_switch_event;
280 static void mux_clone(int cpu)
282 if (!has_mux())
283 return;
285 memcpy(per_cpu(cpu_msrs, cpu).multiplex,
286 per_cpu(cpu_msrs, 0).multiplex,
287 sizeof(struct op_msr) * model->num_virt_counters);
290 #else
292 inline int op_x86_phys_to_virt(int phys) { return phys; }
293 inline int op_x86_virt_to_phys(int virt) { return virt; }
294 static inline void nmi_shutdown_mux(void) { }
295 static inline int nmi_setup_mux(void) { return 1; }
296 static inline void
297 nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs) { }
298 static inline void mux_init(struct oprofile_operations *ops) { }
299 static void mux_clone(int cpu) { }
301 #endif
303 static void free_msrs(void)
305 int i;
306 for_each_possible_cpu(i) {
307 kfree(per_cpu(cpu_msrs, i).counters);
308 per_cpu(cpu_msrs, i).counters = NULL;
309 kfree(per_cpu(cpu_msrs, i).controls);
310 per_cpu(cpu_msrs, i).controls = NULL;
312 nmi_shutdown_mux();
315 static int allocate_msrs(void)
317 size_t controls_size = sizeof(struct op_msr) * model->num_controls;
318 size_t counters_size = sizeof(struct op_msr) * model->num_counters;
320 int i;
321 for_each_possible_cpu(i) {
322 per_cpu(cpu_msrs, i).counters = kzalloc(counters_size,
323 GFP_KERNEL);
324 if (!per_cpu(cpu_msrs, i).counters)
325 goto fail;
326 per_cpu(cpu_msrs, i).controls = kzalloc(controls_size,
327 GFP_KERNEL);
328 if (!per_cpu(cpu_msrs, i).controls)
329 goto fail;
332 if (!nmi_setup_mux())
333 goto fail;
335 return 1;
337 fail:
338 free_msrs();
339 return 0;
342 static void nmi_cpu_setup(void *dummy)
344 int cpu = smp_processor_id();
345 struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
346 nmi_cpu_save_registers(msrs);
347 raw_spin_lock(&oprofilefs_lock);
348 model->setup_ctrs(model, msrs);
349 nmi_cpu_setup_mux(cpu, msrs);
350 raw_spin_unlock(&oprofilefs_lock);
351 per_cpu(saved_lvtpc, cpu) = apic_read(APIC_LVTPC);
352 apic_write(APIC_LVTPC, APIC_DM_NMI);
355 static void nmi_cpu_restore_registers(struct op_msrs *msrs)
357 struct op_msr *counters = msrs->counters;
358 struct op_msr *controls = msrs->controls;
359 unsigned int i;
361 for (i = 0; i < model->num_controls; ++i) {
362 if (controls[i].addr)
363 wrmsrl(controls[i].addr, controls[i].saved);
366 for (i = 0; i < model->num_counters; ++i) {
367 if (counters[i].addr)
368 wrmsrl(counters[i].addr, counters[i].saved);
372 static void nmi_cpu_shutdown(void *dummy)
374 unsigned int v;
375 int cpu = smp_processor_id();
376 struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
378 /* restoring APIC_LVTPC can trigger an apic error because the delivery
379 * mode and vector nr combination can be illegal. That's by design: on
380 * power on apic lvt contain a zero vector nr which are legal only for
381 * NMI delivery mode. So inhibit apic err before restoring lvtpc
383 v = apic_read(APIC_LVTERR);
384 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
385 apic_write(APIC_LVTPC, per_cpu(saved_lvtpc, cpu));
386 apic_write(APIC_LVTERR, v);
387 nmi_cpu_restore_registers(msrs);
390 static void nmi_cpu_up(void *dummy)
392 if (nmi_enabled)
393 nmi_cpu_setup(dummy);
394 if (ctr_running)
395 nmi_cpu_start(dummy);
398 static void nmi_cpu_down(void *dummy)
400 if (ctr_running)
401 nmi_cpu_stop(dummy);
402 if (nmi_enabled)
403 nmi_cpu_shutdown(dummy);
406 static int nmi_create_files(struct super_block *sb, struct dentry *root)
408 unsigned int i;
410 for (i = 0; i < model->num_virt_counters; ++i) {
411 struct dentry *dir;
412 char buf[4];
414 /* quick little hack to _not_ expose a counter if it is not
415 * available for use. This should protect userspace app.
416 * NOTE: assumes 1:1 mapping here (that counters are organized
417 * sequentially in their struct assignment).
419 if (!avail_to_resrv_perfctr_nmi_bit(op_x86_virt_to_phys(i)))
420 continue;
422 snprintf(buf, sizeof(buf), "%d", i);
423 dir = oprofilefs_mkdir(sb, root, buf);
424 oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);
425 oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event);
426 oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count);
427 oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask);
428 oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel);
429 oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user);
430 oprofilefs_create_ulong(sb, dir, "extra", &counter_config[i].extra);
433 return 0;
436 static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
437 void *data)
439 int cpu = (unsigned long)data;
440 switch (action) {
441 case CPU_DOWN_FAILED:
442 case CPU_ONLINE:
443 smp_call_function_single(cpu, nmi_cpu_up, NULL, 0);
444 break;
445 case CPU_DOWN_PREPARE:
446 smp_call_function_single(cpu, nmi_cpu_down, NULL, 1);
447 break;
449 return NOTIFY_DONE;
452 static struct notifier_block oprofile_cpu_nb = {
453 .notifier_call = oprofile_cpu_notifier
456 static int nmi_setup(void)
458 int err = 0;
459 int cpu;
461 if (!allocate_msrs())
462 return -ENOMEM;
464 /* We need to serialize save and setup for HT because the subset
465 * of msrs are distinct for save and setup operations
468 /* Assume saved/restored counters are the same on all CPUs */
469 err = model->fill_in_addresses(&per_cpu(cpu_msrs, 0));
470 if (err)
471 goto fail;
473 for_each_possible_cpu(cpu) {
474 if (!cpu)
475 continue;
477 memcpy(per_cpu(cpu_msrs, cpu).counters,
478 per_cpu(cpu_msrs, 0).counters,
479 sizeof(struct op_msr) * model->num_counters);
481 memcpy(per_cpu(cpu_msrs, cpu).controls,
482 per_cpu(cpu_msrs, 0).controls,
483 sizeof(struct op_msr) * model->num_controls);
485 mux_clone(cpu);
488 nmi_enabled = 0;
489 ctr_running = 0;
490 /* make variables visible to the nmi handler: */
491 smp_mb();
492 err = register_nmi_handler(NMI_LOCAL, profile_exceptions_notify,
493 0, "oprofile");
494 if (err)
495 goto fail;
497 get_online_cpus();
498 register_cpu_notifier(&oprofile_cpu_nb);
499 nmi_enabled = 1;
500 /* make nmi_enabled visible to the nmi handler: */
501 smp_mb();
502 on_each_cpu(nmi_cpu_setup, NULL, 1);
503 put_online_cpus();
505 return 0;
506 fail:
507 free_msrs();
508 return err;
511 static void nmi_shutdown(void)
513 struct op_msrs *msrs;
515 get_online_cpus();
516 unregister_cpu_notifier(&oprofile_cpu_nb);
517 on_each_cpu(nmi_cpu_shutdown, NULL, 1);
518 nmi_enabled = 0;
519 ctr_running = 0;
520 put_online_cpus();
521 /* make variables visible to the nmi handler: */
522 smp_mb();
523 unregister_nmi_handler(NMI_LOCAL, "oprofile");
524 msrs = &get_cpu_var(cpu_msrs);
525 model->shutdown(msrs);
526 free_msrs();
527 put_cpu_var(cpu_msrs);
530 #ifdef CONFIG_PM
532 static int nmi_suspend(void)
534 /* Only one CPU left, just stop that one */
535 if (nmi_enabled == 1)
536 nmi_cpu_stop(NULL);
537 return 0;
540 static void nmi_resume(void)
542 if (nmi_enabled == 1)
543 nmi_cpu_start(NULL);
546 static struct syscore_ops oprofile_syscore_ops = {
547 .resume = nmi_resume,
548 .suspend = nmi_suspend,
551 static void __init init_suspend_resume(void)
553 register_syscore_ops(&oprofile_syscore_ops);
556 static void exit_suspend_resume(void)
558 unregister_syscore_ops(&oprofile_syscore_ops);
561 #else
563 static inline void init_suspend_resume(void) { }
564 static inline void exit_suspend_resume(void) { }
566 #endif /* CONFIG_PM */
568 static int __init p4_init(char **cpu_type)
570 __u8 cpu_model = boot_cpu_data.x86_model;
572 if (cpu_model > 6 || cpu_model == 5)
573 return 0;
575 #ifndef CONFIG_SMP
576 *cpu_type = "i386/p4";
577 model = &op_p4_spec;
578 return 1;
579 #else
580 switch (smp_num_siblings) {
581 case 1:
582 *cpu_type = "i386/p4";
583 model = &op_p4_spec;
584 return 1;
586 case 2:
587 *cpu_type = "i386/p4-ht";
588 model = &op_p4_ht2_spec;
589 return 1;
591 #endif
593 printk(KERN_INFO "oprofile: P4 HyperThreading detected with > 2 threads\n");
594 printk(KERN_INFO "oprofile: Reverting to timer mode.\n");
595 return 0;
598 enum __force_cpu_type {
599 reserved = 0, /* do not force */
600 timer,
601 arch_perfmon,
604 static int force_cpu_type;
606 static int set_cpu_type(const char *str, struct kernel_param *kp)
608 if (!strcmp(str, "timer")) {
609 force_cpu_type = timer;
610 printk(KERN_INFO "oprofile: forcing NMI timer mode\n");
611 } else if (!strcmp(str, "arch_perfmon")) {
612 force_cpu_type = arch_perfmon;
613 printk(KERN_INFO "oprofile: forcing architectural perfmon\n");
614 } else {
615 force_cpu_type = 0;
618 return 0;
620 module_param_call(cpu_type, set_cpu_type, NULL, NULL, 0);
622 static int __init ppro_init(char **cpu_type)
624 __u8 cpu_model = boot_cpu_data.x86_model;
625 struct op_x86_model_spec *spec = &op_ppro_spec; /* default */
627 if (force_cpu_type == arch_perfmon && cpu_has_arch_perfmon)
628 return 0;
631 * Documentation on identifying Intel processors by CPU family
632 * and model can be found in the Intel Software Developer's
633 * Manuals (SDM):
635 * http://www.intel.com/products/processor/manuals/
637 * As of May 2010 the documentation for this was in the:
638 * "Intel 64 and IA-32 Architectures Software Developer's
639 * Manual Volume 3B: System Programming Guide", "Table B-1
640 * CPUID Signature Values of DisplayFamily_DisplayModel".
642 switch (cpu_model) {
643 case 0 ... 2:
644 *cpu_type = "i386/ppro";
645 break;
646 case 3 ... 5:
647 *cpu_type = "i386/pii";
648 break;
649 case 6 ... 8:
650 case 10 ... 11:
651 *cpu_type = "i386/piii";
652 break;
653 case 9:
654 case 13:
655 *cpu_type = "i386/p6_mobile";
656 break;
657 case 14:
658 *cpu_type = "i386/core";
659 break;
660 case 0x0f:
661 case 0x16:
662 case 0x17:
663 case 0x1d:
664 *cpu_type = "i386/core_2";
665 break;
666 case 0x1a:
667 case 0x1e:
668 case 0x2e:
669 spec = &op_arch_perfmon_spec;
670 *cpu_type = "i386/core_i7";
671 break;
672 case 0x1c:
673 *cpu_type = "i386/atom";
674 break;
675 default:
676 /* Unknown */
677 return 0;
680 model = spec;
681 return 1;
684 int __init op_nmi_init(struct oprofile_operations *ops)
686 __u8 vendor = boot_cpu_data.x86_vendor;
687 __u8 family = boot_cpu_data.x86;
688 char *cpu_type = NULL;
689 int ret = 0;
691 if (!cpu_has_apic)
692 return -ENODEV;
694 if (force_cpu_type == timer)
695 return -ENODEV;
697 switch (vendor) {
698 case X86_VENDOR_AMD:
699 /* Needs to be at least an Athlon (or hammer in 32bit mode) */
701 switch (family) {
702 case 6:
703 cpu_type = "i386/athlon";
704 break;
705 case 0xf:
707 * Actually it could be i386/hammer too, but
708 * give user space an consistent name.
710 cpu_type = "x86-64/hammer";
711 break;
712 case 0x10:
713 cpu_type = "x86-64/family10";
714 break;
715 case 0x11:
716 cpu_type = "x86-64/family11h";
717 break;
718 case 0x12:
719 cpu_type = "x86-64/family12h";
720 break;
721 case 0x14:
722 cpu_type = "x86-64/family14h";
723 break;
724 case 0x15:
725 cpu_type = "x86-64/family15h";
726 break;
727 default:
728 return -ENODEV;
730 model = &op_amd_spec;
731 break;
733 case X86_VENDOR_INTEL:
734 switch (family) {
735 /* Pentium IV */
736 case 0xf:
737 p4_init(&cpu_type);
738 break;
740 /* A P6-class processor */
741 case 6:
742 ppro_init(&cpu_type);
743 break;
745 default:
746 break;
749 if (cpu_type)
750 break;
752 if (!cpu_has_arch_perfmon)
753 return -ENODEV;
755 /* use arch perfmon as fallback */
756 cpu_type = "i386/arch_perfmon";
757 model = &op_arch_perfmon_spec;
758 break;
760 default:
761 return -ENODEV;
764 /* default values, can be overwritten by model */
765 ops->create_files = nmi_create_files;
766 ops->setup = nmi_setup;
767 ops->shutdown = nmi_shutdown;
768 ops->start = nmi_start;
769 ops->stop = nmi_stop;
770 ops->cpu_type = cpu_type;
772 if (model->init)
773 ret = model->init(ops);
774 if (ret)
775 return ret;
777 if (!model->num_virt_counters)
778 model->num_virt_counters = model->num_counters;
780 mux_init(ops);
782 init_suspend_resume();
784 printk(KERN_INFO "oprofile: using NMI interrupt.\n");
785 return 0;
788 void op_nmi_exit(void)
790 exit_suspend_resume();