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Merge tag 'powerpc-5.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...
[linux/fpc-iii.git] / kernel / trace / trace_events_hist.c
blob39ebe1826fc3872d734ae5052614a6dbeab03190
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * trace_events_hist - trace event hist triggers
4 *
5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
6 */
7
8 #include <linux/module.h>
9 #include <linux/kallsyms.h>
10 #include <linux/security.h>
11 #include <linux/mutex.h>
12 #include <linux/slab.h>
13 #include <linux/stacktrace.h>
14 #include <linux/rculist.h>
15 #include <linux/tracefs.h>
16
17 /* for gfp flag names */
18 #include <linux/trace_events.h>
19 #include <trace/events/mmflags.h>
20
21 #include "tracing_map.h"
22 #include "trace_synth.h"
23
24 #define ERRORS \
25 C(NONE, "No error"), \
26 C(DUPLICATE_VAR, "Variable already defined"), \
27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \
28 C(TOO_MANY_VARS, "Too many variables defined"), \
29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \
30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \
31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \
32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \
33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \
34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \
35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \
36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \
37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \
38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \
39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \
40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \
41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \
42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \
43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \
44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \
45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \
46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \
47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \
48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \
49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \
50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \
51 C(TOO_MANY_PARAMS, "Too many action params"), \
52 C(PARAM_NOT_FOUND, "Couldn't find param"), \
53 C(INVALID_PARAM, "Invalid action param"), \
54 C(ACTION_NOT_FOUND, "No action found"), \
55 C(NO_SAVE_PARAMS, "No params found for save()"), \
56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \
57 C(ACTION_MISMATCH, "Handler doesn't support action"), \
58 C(NO_CLOSING_PAREN, "No closing paren found"), \
59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \
60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \
61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \
62 C(VAR_NOT_FOUND, "Couldn't find variable"), \
63 C(FIELD_NOT_FOUND, "Couldn't find field"), \
64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \
65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \
66 C(EMPTY_SORT_FIELD, "Empty sort field"), \
67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \
68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"),
69
70 #undef C
71 #define C(a, b) HIST_ERR_##a
72
73 enum { ERRORS };
74
75 #undef C
76 #define C(a, b) b
77
78 static const char *err_text[] = { ERRORS };
79
80 struct hist_field;
81
82 typedef u64 (*hist_field_fn_t) (struct hist_field *field,
83 struct tracing_map_elt *elt,
84 struct ring_buffer_event *rbe,
85 void *event);
86
87 #define HIST_FIELD_OPERANDS_MAX 2
88 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
89 #define HIST_ACTIONS_MAX 8
90
91 enum field_op_id {
92 FIELD_OP_NONE,
93 FIELD_OP_PLUS,
94 FIELD_OP_MINUS,
95 FIELD_OP_UNARY_MINUS,
96 };
97
98 /*
99 * A hist_var (histogram variable) contains variable information for
100 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF
101 * flag set. A hist_var has a variable name e.g. ts0, and is
102 * associated with a given histogram trigger, as specified by
103 * hist_data. The hist_var idx is the unique index assigned to the
104 * variable by the hist trigger's tracing_map. The idx is what is
105 * used to set a variable's value and, by a variable reference, to
106 * retrieve it.
107 */
108 struct hist_var {
109 char *name;
110 struct hist_trigger_data *hist_data;
111 unsigned int idx;
112 };
113
114 struct hist_field {
115 struct ftrace_event_field *field;
116 unsigned long flags;
117 hist_field_fn_t fn;
118 unsigned int ref;
119 unsigned int size;
120 unsigned int offset;
121 unsigned int is_signed;
122 const char *type;
123 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
124 struct hist_trigger_data *hist_data;
125
126 /*
127 * Variable fields contain variable-specific info in var.
128 */
129 struct hist_var var;
130 enum field_op_id operator;
131 char *system;
132 char *event_name;
133
134 /*
135 * The name field is used for EXPR and VAR_REF fields. VAR
136 * fields contain the variable name in var.name.
137 */
138 char *name;
139
140 /*
141 * When a histogram trigger is hit, if it has any references
142 * to variables, the values of those variables are collected
143 * into a var_ref_vals array by resolve_var_refs(). The
144 * current value of each variable is read from the tracing_map
145 * using the hist field's hist_var.idx and entered into the
146 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx].
147 */
148 unsigned int var_ref_idx;
149 bool read_once;
150
151 unsigned int var_str_idx;
152 };
153
154 static u64 hist_field_none(struct hist_field *field,
155 struct tracing_map_elt *elt,
156 struct ring_buffer_event *rbe,
157 void *event)
158 {
159 return 0;
160 }
161
162 static u64 hist_field_counter(struct hist_field *field,
163 struct tracing_map_elt *elt,
164 struct ring_buffer_event *rbe,
165 void *event)
166 {
167 return 1;
168 }
169
170 static u64 hist_field_string(struct hist_field *hist_field,
171 struct tracing_map_elt *elt,
172 struct ring_buffer_event *rbe,
173 void *event)
174 {
175 char *addr = (char *)(event + hist_field->field->offset);
176
177 return (u64)(unsigned long)addr;
178 }
179
180 static u64 hist_field_dynstring(struct hist_field *hist_field,
181 struct tracing_map_elt *elt,
182 struct ring_buffer_event *rbe,
183 void *event)
184 {
185 u32 str_item = *(u32 *)(event + hist_field->field->offset);
186 int str_loc = str_item & 0xffff;
187 char *addr = (char *)(event + str_loc);
188
189 return (u64)(unsigned long)addr;
190 }
191
192 static u64 hist_field_pstring(struct hist_field *hist_field,
193 struct tracing_map_elt *elt,
194 struct ring_buffer_event *rbe,
195 void *event)
196 {
197 char **addr = (char **)(event + hist_field->field->offset);
198
199 return (u64)(unsigned long)*addr;
200 }
201
202 static u64 hist_field_log2(struct hist_field *hist_field,
203 struct tracing_map_elt *elt,
204 struct ring_buffer_event *rbe,
205 void *event)
206 {
207 struct hist_field *operand = hist_field->operands[0];
208
209 u64 val = operand->fn(operand, elt, rbe, event);
210
211 return (u64) ilog2(roundup_pow_of_two(val));
212 }
213
214 static u64 hist_field_plus(struct hist_field *hist_field,
215 struct tracing_map_elt *elt,
216 struct ring_buffer_event *rbe,
217 void *event)
218 {
219 struct hist_field *operand1 = hist_field->operands[0];
220 struct hist_field *operand2 = hist_field->operands[1];
221
222 u64 val1 = operand1->fn(operand1, elt, rbe, event);
223 u64 val2 = operand2->fn(operand2, elt, rbe, event);
224
225 return val1 + val2;
226 }
227
228 static u64 hist_field_minus(struct hist_field *hist_field,
229 struct tracing_map_elt *elt,
230 struct ring_buffer_event *rbe,
231 void *event)
232 {
233 struct hist_field *operand1 = hist_field->operands[0];
234 struct hist_field *operand2 = hist_field->operands[1];
235
236 u64 val1 = operand1->fn(operand1, elt, rbe, event);
237 u64 val2 = operand2->fn(operand2, elt, rbe, event);
238
239 return val1 - val2;
240 }
241
242 static u64 hist_field_unary_minus(struct hist_field *hist_field,
243 struct tracing_map_elt *elt,
244 struct ring_buffer_event *rbe,
245 void *event)
246 {
247 struct hist_field *operand = hist_field->operands[0];
248
249 s64 sval = (s64)operand->fn(operand, elt, rbe, event);
250 u64 val = (u64)-sval;
251
252 return val;
253 }
254
255 #define DEFINE_HIST_FIELD_FN(type) \
256 static u64 hist_field_##type(struct hist_field *hist_field, \
257 struct tracing_map_elt *elt, \
258 struct ring_buffer_event *rbe, \
259 void *event) \
260 { \
261 type *addr = (type *)(event + hist_field->field->offset); \
262 \
263 return (u64)(unsigned long)*addr; \
264 }
265
266 DEFINE_HIST_FIELD_FN(s64);
267 DEFINE_HIST_FIELD_FN(u64);
268 DEFINE_HIST_FIELD_FN(s32);
269 DEFINE_HIST_FIELD_FN(u32);
270 DEFINE_HIST_FIELD_FN(s16);
271 DEFINE_HIST_FIELD_FN(u16);
272 DEFINE_HIST_FIELD_FN(s8);
273 DEFINE_HIST_FIELD_FN(u8);
274
275 #define for_each_hist_field(i, hist_data) \
276 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
277
278 #define for_each_hist_val_field(i, hist_data) \
279 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
280
281 #define for_each_hist_key_field(i, hist_data) \
282 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
283
284 #define HIST_STACKTRACE_DEPTH 16
285 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
286 #define HIST_STACKTRACE_SKIP 5
287
288 #define HITCOUNT_IDX 0
289 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
290
291 enum hist_field_flags {
292 HIST_FIELD_FL_HITCOUNT = 1 << 0,
293 HIST_FIELD_FL_KEY = 1 << 1,
294 HIST_FIELD_FL_STRING = 1 << 2,
295 HIST_FIELD_FL_HEX = 1 << 3,
296 HIST_FIELD_FL_SYM = 1 << 4,
297 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
298 HIST_FIELD_FL_EXECNAME = 1 << 6,
299 HIST_FIELD_FL_SYSCALL = 1 << 7,
300 HIST_FIELD_FL_STACKTRACE = 1 << 8,
301 HIST_FIELD_FL_LOG2 = 1 << 9,
302 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
303 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
304 HIST_FIELD_FL_VAR = 1 << 12,
305 HIST_FIELD_FL_EXPR = 1 << 13,
306 HIST_FIELD_FL_VAR_REF = 1 << 14,
307 HIST_FIELD_FL_CPU = 1 << 15,
308 HIST_FIELD_FL_ALIAS = 1 << 16,
309 };
310
311 struct var_defs {
312 unsigned int n_vars;
313 char *name[TRACING_MAP_VARS_MAX];
314 char *expr[TRACING_MAP_VARS_MAX];
315 };
316
317 struct hist_trigger_attrs {
318 char *keys_str;
319 char *vals_str;
320 char *sort_key_str;
321 char *name;
322 char *clock;
323 bool pause;
324 bool cont;
325 bool clear;
326 bool ts_in_usecs;
327 unsigned int map_bits;
328
329 char *assignment_str[TRACING_MAP_VARS_MAX];
330 unsigned int n_assignments;
331
332 char *action_str[HIST_ACTIONS_MAX];
333 unsigned int n_actions;
334
335 struct var_defs var_defs;
336 };
337
338 struct field_var {
339 struct hist_field *var;
340 struct hist_field *val;
341 };
342
343 struct field_var_hist {
344 struct hist_trigger_data *hist_data;
345 char *cmd;
346 };
347
348 struct hist_trigger_data {
349 struct hist_field *fields[HIST_FIELDS_MAX];
350 unsigned int n_vals;
351 unsigned int n_keys;
352 unsigned int n_fields;
353 unsigned int n_vars;
354 unsigned int n_var_str;
355 unsigned int key_size;
356 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
357 unsigned int n_sort_keys;
358 struct trace_event_file *event_file;
359 struct hist_trigger_attrs *attrs;
360 struct tracing_map *map;
361 bool enable_timestamps;
362 bool remove;
363 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
364 unsigned int n_var_refs;
365
366 struct action_data *actions[HIST_ACTIONS_MAX];
367 unsigned int n_actions;
368
369 struct field_var *field_vars[SYNTH_FIELDS_MAX];
370 unsigned int n_field_vars;
371 unsigned int n_field_var_str;
372 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
373 unsigned int n_field_var_hists;
374
375 struct field_var *save_vars[SYNTH_FIELDS_MAX];
376 unsigned int n_save_vars;
377 unsigned int n_save_var_str;
378 };
379
380 struct action_data;
381
382 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
383 struct tracing_map_elt *elt, void *rec,
384 struct ring_buffer_event *rbe, void *key,
385 struct action_data *data, u64 *var_ref_vals);
386
387 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val);
388
389 enum handler_id {
390 HANDLER_ONMATCH = 1,
391 HANDLER_ONMAX,
392 HANDLER_ONCHANGE,
393 };
394
395 enum action_id {
396 ACTION_SAVE = 1,
397 ACTION_TRACE,
398 ACTION_SNAPSHOT,
399 };
400
401 struct action_data {
402 enum handler_id handler;
403 enum action_id action;
404 char *action_name;
405 action_fn_t fn;
406
407 unsigned int n_params;
408 char *params[SYNTH_FIELDS_MAX];
409
410 /*
411 * When a histogram trigger is hit, the values of any
412 * references to variables, including variables being passed
413 * as parameters to synthetic events, are collected into a
414 * var_ref_vals array. This var_ref_idx array is an array of
415 * indices into the var_ref_vals array, one for each synthetic
416 * event param, and is passed to the synthetic event
417 * invocation.
418 */
419 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX];
420 struct synth_event *synth_event;
421 bool use_trace_keyword;
422 char *synth_event_name;
423
424 union {
425 struct {
426 char *event;
427 char *event_system;
428 } match_data;
429
430 struct {
431 /*
432 * var_str contains the $-unstripped variable
433 * name referenced by var_ref, and used when
434 * printing the action. Because var_ref
435 * creation is deferred to create_actions(),
436 * we need a per-action way to save it until
437 * then, thus var_str.
438 */
439 char *var_str;
440
441 /*
442 * var_ref refers to the variable being
443 * tracked e.g onmax($var).
444 */
445 struct hist_field *var_ref;
446
447 /*
448 * track_var contains the 'invisible' tracking
449 * variable created to keep the current
450 * e.g. max value.
451 */
452 struct hist_field *track_var;
453
454 check_track_val_fn_t check_val;
455 action_fn_t save_data;
456 } track_data;
457 };
458 };
459
460 struct track_data {
461 u64 track_val;
462 bool updated;
463
464 unsigned int key_len;
465 void *key;
466 struct tracing_map_elt elt;
467
468 struct action_data *action_data;
469 struct hist_trigger_data *hist_data;
470 };
471
472 struct hist_elt_data {
473 char *comm;
474 u64 *var_ref_vals;
475 char *field_var_str[SYNTH_FIELDS_MAX];
476 };
477
478 struct snapshot_context {
479 struct tracing_map_elt *elt;
480 void *key;
481 };
482
483 static void track_data_free(struct track_data *track_data)
484 {
485 struct hist_elt_data *elt_data;
486
487 if (!track_data)
488 return;
489
490 kfree(track_data->key);
491
492 elt_data = track_data->elt.private_data;
493 if (elt_data) {
494 kfree(elt_data->comm);
495 kfree(elt_data);
496 }
497
498 kfree(track_data);
499 }
500
501 static struct track_data *track_data_alloc(unsigned int key_len,
502 struct action_data *action_data,
503 struct hist_trigger_data *hist_data)
504 {
505 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
506 struct hist_elt_data *elt_data;
507
508 if (!data)
509 return ERR_PTR(-ENOMEM);
510
511 data->key = kzalloc(key_len, GFP_KERNEL);
512 if (!data->key) {
513 track_data_free(data);
514 return ERR_PTR(-ENOMEM);
515 }
516
517 data->key_len = key_len;
518 data->action_data = action_data;
519 data->hist_data = hist_data;
520
521 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
522 if (!elt_data) {
523 track_data_free(data);
524 return ERR_PTR(-ENOMEM);
525 }
526
527 data->elt.private_data = elt_data;
528
529 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL);
530 if (!elt_data->comm) {
531 track_data_free(data);
532 return ERR_PTR(-ENOMEM);
533 }
534
535 return data;
536 }
537
538 static char last_cmd[MAX_FILTER_STR_VAL];
539 static char last_cmd_loc[MAX_FILTER_STR_VAL];
540
541 static int errpos(char *str)
542 {
543 return err_pos(last_cmd, str);
544 }
545
546 static void last_cmd_set(struct trace_event_file *file, char *str)
547 {
548 const char *system = NULL, *name = NULL;
549 struct trace_event_call *call;
550
551 if (!str)
552 return;
553
554 strcpy(last_cmd, "hist:");
555 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:"));
556
557 if (file) {
558 call = file->event_call;
559 system = call->class->system;
560 if (system) {
561 name = trace_event_name(call);
562 if (!name)
563 system = NULL;
564 }
565 }
566
567 if (system)
568 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name);
569 }
570
571 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos)
572 {
573 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,
574 err_type, err_pos);
575 }
576
577 static void hist_err_clear(void)
578 {
579 last_cmd[0] = '\0';
580 last_cmd_loc[0] = '\0';
581 }
582
583 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
584 unsigned int *var_ref_idx);
585
586 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
587 unsigned int *var_ref_idx)
588 {
589 struct tracepoint *tp = event->tp;
590
591 if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
592 struct tracepoint_func *probe_func_ptr;
593 synth_probe_func_t probe_func;
594 void *__data;
595
596 if (!(cpu_online(raw_smp_processor_id())))
597 return;
598
599 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
600 if (probe_func_ptr) {
601 do {
602 probe_func = probe_func_ptr->func;
603 __data = probe_func_ptr->data;
604 probe_func(__data, var_ref_vals, var_ref_idx);
605 } while ((++probe_func_ptr)->func);
606 }
607 }
608 }
609
610 static void action_trace(struct hist_trigger_data *hist_data,
611 struct tracing_map_elt *elt, void *rec,
612 struct ring_buffer_event *rbe, void *key,
613 struct action_data *data, u64 *var_ref_vals)
614 {
615 struct synth_event *event = data->synth_event;
616
617 trace_synth(event, var_ref_vals, data->var_ref_idx);
618 }
619
620 struct hist_var_data {
621 struct list_head list;
622 struct hist_trigger_data *hist_data;
623 };
624
625 static u64 hist_field_timestamp(struct hist_field *hist_field,
626 struct tracing_map_elt *elt,
627 struct ring_buffer_event *rbe,
628 void *event)
629 {
630 struct hist_trigger_data *hist_data = hist_field->hist_data;
631 struct trace_array *tr = hist_data->event_file->tr;
632
633 u64 ts = ring_buffer_event_time_stamp(rbe);
634
635 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
636 ts = ns2usecs(ts);
637
638 return ts;
639 }
640
641 static u64 hist_field_cpu(struct hist_field *hist_field,
642 struct tracing_map_elt *elt,
643 struct ring_buffer_event *rbe,
644 void *event)
645 {
646 int cpu = smp_processor_id();
647
648 return cpu;
649 }
650
651 /**
652 * check_field_for_var_ref - Check if a VAR_REF field references a variable
653 * @hist_field: The VAR_REF field to check
654 * @var_data: The hist trigger that owns the variable
655 * @var_idx: The trigger variable identifier
656 *
657 * Check the given VAR_REF field to see whether or not it references
658 * the given variable associated with the given trigger.
659 *
660 * Return: The VAR_REF field if it does reference the variable, NULL if not
661 */
662 static struct hist_field *
663 check_field_for_var_ref(struct hist_field *hist_field,
664 struct hist_trigger_data *var_data,
665 unsigned int var_idx)
666 {
667 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF));
668
669 if (hist_field && hist_field->var.idx == var_idx &&
670 hist_field->var.hist_data == var_data)
671 return hist_field;
672
673 return NULL;
674 }
675
676 /**
677 * find_var_ref - Check if a trigger has a reference to a trigger variable
678 * @hist_data: The hist trigger that might have a reference to the variable
679 * @var_data: The hist trigger that owns the variable
680 * @var_idx: The trigger variable identifier
681 *
682 * Check the list of var_refs[] on the first hist trigger to see
683 * whether any of them are references to the variable on the second
684 * trigger.
685 *
686 * Return: The VAR_REF field referencing the variable if so, NULL if not
687 */
688 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
689 struct hist_trigger_data *var_data,
690 unsigned int var_idx)
691 {
692 struct hist_field *hist_field;
693 unsigned int i;
694
695 for (i = 0; i < hist_data->n_var_refs; i++) {
696 hist_field = hist_data->var_refs[i];
697 if (check_field_for_var_ref(hist_field, var_data, var_idx))
698 return hist_field;
699 }
700
701 return NULL;
702 }
703
704 /**
705 * find_any_var_ref - Check if there is a reference to a given trigger variable
706 * @hist_data: The hist trigger
707 * @var_idx: The trigger variable identifier
708 *
709 * Check to see whether the given variable is currently referenced by
710 * any other trigger.
711 *
712 * The trigger the variable is defined on is explicitly excluded - the
713 * assumption being that a self-reference doesn't prevent a trigger
714 * from being removed.
715 *
716 * Return: The VAR_REF field referencing the variable if so, NULL if not
717 */
718 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
719 unsigned int var_idx)
720 {
721 struct trace_array *tr = hist_data->event_file->tr;
722 struct hist_field *found = NULL;
723 struct hist_var_data *var_data;
724
725 list_for_each_entry(var_data, &tr->hist_vars, list) {
726 if (var_data->hist_data == hist_data)
727 continue;
728 found = find_var_ref(var_data->hist_data, hist_data, var_idx);
729 if (found)
730 break;
731 }
732
733 return found;
734 }
735
736 /**
737 * check_var_refs - Check if there is a reference to any of trigger's variables
738 * @hist_data: The hist trigger
739 *
740 * A trigger can define one or more variables. If any one of them is
741 * currently referenced by any other trigger, this function will
742 * determine that.
743
744 * Typically used to determine whether or not a trigger can be removed
745 * - if there are any references to a trigger's variables, it cannot.
746 *
747 * Return: True if there is a reference to any of trigger's variables
748 */
749 static bool check_var_refs(struct hist_trigger_data *hist_data)
750 {
751 struct hist_field *field;
752 bool found = false;
753 int i;
754
755 for_each_hist_field(i, hist_data) {
756 field = hist_data->fields[i];
757 if (field && field->flags & HIST_FIELD_FL_VAR) {
758 if (find_any_var_ref(hist_data, field->var.idx)) {
759 found = true;
760 break;
761 }
762 }
763 }
764
765 return found;
766 }
767
768 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
769 {
770 struct trace_array *tr = hist_data->event_file->tr;
771 struct hist_var_data *var_data, *found = NULL;
772
773 list_for_each_entry(var_data, &tr->hist_vars, list) {
774 if (var_data->hist_data == hist_data) {
775 found = var_data;
776 break;
777 }
778 }
779
780 return found;
781 }
782
783 static bool field_has_hist_vars(struct hist_field *hist_field,
784 unsigned int level)
785 {
786 int i;
787
788 if (level > 3)
789 return false;
790
791 if (!hist_field)
792 return false;
793
794 if (hist_field->flags & HIST_FIELD_FL_VAR ||
795 hist_field->flags & HIST_FIELD_FL_VAR_REF)
796 return true;
797
798 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
799 struct hist_field *operand;
800
801 operand = hist_field->operands[i];
802 if (field_has_hist_vars(operand, level + 1))
803 return true;
804 }
805
806 return false;
807 }
808
809 static bool has_hist_vars(struct hist_trigger_data *hist_data)
810 {
811 struct hist_field *hist_field;
812 int i;
813
814 for_each_hist_field(i, hist_data) {
815 hist_field = hist_data->fields[i];
816 if (field_has_hist_vars(hist_field, 0))
817 return true;
818 }
819
820 return false;
821 }
822
823 static int save_hist_vars(struct hist_trigger_data *hist_data)
824 {
825 struct trace_array *tr = hist_data->event_file->tr;
826 struct hist_var_data *var_data;
827
828 var_data = find_hist_vars(hist_data);
829 if (var_data)
830 return 0;
831
832 if (tracing_check_open_get_tr(tr))
833 return -ENODEV;
834
835 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
836 if (!var_data) {
837 trace_array_put(tr);
838 return -ENOMEM;
839 }
840
841 var_data->hist_data = hist_data;
842 list_add(&var_data->list, &tr->hist_vars);
843
844 return 0;
845 }
846
847 static void remove_hist_vars(struct hist_trigger_data *hist_data)
848 {
849 struct trace_array *tr = hist_data->event_file->tr;
850 struct hist_var_data *var_data;
851
852 var_data = find_hist_vars(hist_data);
853 if (!var_data)
854 return;
855
856 if (WARN_ON(check_var_refs(hist_data)))
857 return;
858
859 list_del(&var_data->list);
860
861 kfree(var_data);
862
863 trace_array_put(tr);
864 }
865
866 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
867 const char *var_name)
868 {
869 struct hist_field *hist_field, *found = NULL;
870 int i;
871
872 for_each_hist_field(i, hist_data) {
873 hist_field = hist_data->fields[i];
874 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
875 strcmp(hist_field->var.name, var_name) == 0) {
876 found = hist_field;
877 break;
878 }
879 }
880
881 return found;
882 }
883
884 static struct hist_field *find_var(struct hist_trigger_data *hist_data,
885 struct trace_event_file *file,
886 const char *var_name)
887 {
888 struct hist_trigger_data *test_data;
889 struct event_trigger_data *test;
890 struct hist_field *hist_field;
891
892 lockdep_assert_held(&event_mutex);
893
894 hist_field = find_var_field(hist_data, var_name);
895 if (hist_field)
896 return hist_field;
897
898 list_for_each_entry(test, &file->triggers, list) {
899 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
900 test_data = test->private_data;
901 hist_field = find_var_field(test_data, var_name);
902 if (hist_field)
903 return hist_field;
904 }
905 }
906
907 return NULL;
908 }
909
910 static struct trace_event_file *find_var_file(struct trace_array *tr,
911 char *system,
912 char *event_name,
913 char *var_name)
914 {
915 struct hist_trigger_data *var_hist_data;
916 struct hist_var_data *var_data;
917 struct trace_event_file *file, *found = NULL;
918
919 if (system)
920 return find_event_file(tr, system, event_name);
921
922 list_for_each_entry(var_data, &tr->hist_vars, list) {
923 var_hist_data = var_data->hist_data;
924 file = var_hist_data->event_file;
925 if (file == found)
926 continue;
927
928 if (find_var_field(var_hist_data, var_name)) {
929 if (found) {
930 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name));
931 return NULL;
932 }
933
934 found = file;
935 }
936 }
937
938 return found;
939 }
940
941 static struct hist_field *find_file_var(struct trace_event_file *file,
942 const char *var_name)
943 {
944 struct hist_trigger_data *test_data;
945 struct event_trigger_data *test;
946 struct hist_field *hist_field;
947
948 lockdep_assert_held(&event_mutex);
949
950 list_for_each_entry(test, &file->triggers, list) {
951 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
952 test_data = test->private_data;
953 hist_field = find_var_field(test_data, var_name);
954 if (hist_field)
955 return hist_field;
956 }
957 }
958
959 return NULL;
960 }
961
962 static struct hist_field *
963 find_match_var(struct hist_trigger_data *hist_data, char *var_name)
964 {
965 struct trace_array *tr = hist_data->event_file->tr;
966 struct hist_field *hist_field, *found = NULL;
967 struct trace_event_file *file;
968 unsigned int i;
969
970 for (i = 0; i < hist_data->n_actions; i++) {
971 struct action_data *data = hist_data->actions[i];
972
973 if (data->handler == HANDLER_ONMATCH) {
974 char *system = data->match_data.event_system;
975 char *event_name = data->match_data.event;
976
977 file = find_var_file(tr, system, event_name, var_name);
978 if (!file)
979 continue;
980 hist_field = find_file_var(file, var_name);
981 if (hist_field) {
982 if (found) {
983 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE,
984 errpos(var_name));
985 return ERR_PTR(-EINVAL);
986 }
987
988 found = hist_field;
989 }
990 }
991 }
992 return found;
993 }
994
995 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
996 char *system,
997 char *event_name,
998 char *var_name)
999 {
1000 struct trace_array *tr = hist_data->event_file->tr;
1001 struct hist_field *hist_field = NULL;
1002 struct trace_event_file *file;
1003
1004 if (!system || !event_name) {
1005 hist_field = find_match_var(hist_data, var_name);
1006 if (IS_ERR(hist_field))
1007 return NULL;
1008 if (hist_field)
1009 return hist_field;
1010 }
1011
1012 file = find_var_file(tr, system, event_name, var_name);
1013 if (!file)
1014 return NULL;
1015
1016 hist_field = find_file_var(file, var_name);
1017
1018 return hist_field;
1019 }
1020
1021 static u64 hist_field_var_ref(struct hist_field *hist_field,
1022 struct tracing_map_elt *elt,
1023 struct ring_buffer_event *rbe,
1024 void *event)
1025 {
1026 struct hist_elt_data *elt_data;
1027 u64 var_val = 0;
1028
1029 if (WARN_ON_ONCE(!elt))
1030 return var_val;
1031
1032 elt_data = elt->private_data;
1033 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1034
1035 return var_val;
1036 }
1037
1038 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1039 u64 *var_ref_vals, bool self)
1040 {
1041 struct hist_trigger_data *var_data;
1042 struct tracing_map_elt *var_elt;
1043 struct hist_field *hist_field;
1044 unsigned int i, var_idx;
1045 bool resolved = true;
1046 u64 var_val = 0;
1047
1048 for (i = 0; i < hist_data->n_var_refs; i++) {
1049 hist_field = hist_data->var_refs[i];
1050 var_idx = hist_field->var.idx;
1051 var_data = hist_field->var.hist_data;
1052
1053 if (var_data == NULL) {
1054 resolved = false;
1055 break;
1056 }
1057
1058 if ((self && var_data != hist_data) ||
1059 (!self && var_data == hist_data))
1060 continue;
1061
1062 var_elt = tracing_map_lookup(var_data->map, key);
1063 if (!var_elt) {
1064 resolved = false;
1065 break;
1066 }
1067
1068 if (!tracing_map_var_set(var_elt, var_idx)) {
1069 resolved = false;
1070 break;
1071 }
1072
1073 if (self || !hist_field->read_once)
1074 var_val = tracing_map_read_var(var_elt, var_idx);
1075 else
1076 var_val = tracing_map_read_var_once(var_elt, var_idx);
1077
1078 var_ref_vals[i] = var_val;
1079 }
1080
1081 return resolved;
1082 }
1083
1084 static const char *hist_field_name(struct hist_field *field,
1085 unsigned int level)
1086 {
1087 const char *field_name = "";
1088
1089 if (level > 1)
1090 return field_name;
1091
1092 if (field->field)
1093 field_name = field->field->name;
1094 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1095 field->flags & HIST_FIELD_FL_ALIAS)
1096 field_name = hist_field_name(field->operands[0], ++level);
1097 else if (field->flags & HIST_FIELD_FL_CPU)
1098 field_name = "cpu";
1099 else if (field->flags & HIST_FIELD_FL_EXPR ||
1100 field->flags & HIST_FIELD_FL_VAR_REF) {
1101 if (field->system) {
1102 static char full_name[MAX_FILTER_STR_VAL];
1103
1104 strcat(full_name, field->system);
1105 strcat(full_name, ".");
1106 strcat(full_name, field->event_name);
1107 strcat(full_name, ".");
1108 strcat(full_name, field->name);
1109 field_name = full_name;
1110 } else
1111 field_name = field->name;
1112 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1113 field_name = "common_timestamp";
1114
1115 if (field_name == NULL)
1116 field_name = "";
1117
1118 return field_name;
1119 }
1120
1121 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
1122 {
1123 hist_field_fn_t fn = NULL;
1124
1125 switch (field_size) {
1126 case 8:
1127 if (field_is_signed)
1128 fn = hist_field_s64;
1129 else
1130 fn = hist_field_u64;
1131 break;
1132 case 4:
1133 if (field_is_signed)
1134 fn = hist_field_s32;
1135 else
1136 fn = hist_field_u32;
1137 break;
1138 case 2:
1139 if (field_is_signed)
1140 fn = hist_field_s16;
1141 else
1142 fn = hist_field_u16;
1143 break;
1144 case 1:
1145 if (field_is_signed)
1146 fn = hist_field_s8;
1147 else
1148 fn = hist_field_u8;
1149 break;
1150 }
1151
1152 return fn;
1153 }
1154
1155 static int parse_map_size(char *str)
1156 {
1157 unsigned long size, map_bits;
1158 int ret;
1159
1160 ret = kstrtoul(str, 0, &size);
1161 if (ret)
1162 goto out;
1163
1164 map_bits = ilog2(roundup_pow_of_two(size));
1165 if (map_bits < TRACING_MAP_BITS_MIN ||
1166 map_bits > TRACING_MAP_BITS_MAX)
1167 ret = -EINVAL;
1168 else
1169 ret = map_bits;
1170 out:
1171 return ret;
1172 }
1173
1174 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1175 {
1176 unsigned int i;
1177
1178 if (!attrs)
1179 return;
1180
1181 for (i = 0; i < attrs->n_assignments; i++)
1182 kfree(attrs->assignment_str[i]);
1183
1184 for (i = 0; i < attrs->n_actions; i++)
1185 kfree(attrs->action_str[i]);
1186
1187 kfree(attrs->name);
1188 kfree(attrs->sort_key_str);
1189 kfree(attrs->keys_str);
1190 kfree(attrs->vals_str);
1191 kfree(attrs->clock);
1192 kfree(attrs);
1193 }
1194
1195 static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1196 {
1197 int ret = -EINVAL;
1198
1199 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1200 return ret;
1201
1202 if ((str_has_prefix(str, "onmatch(")) ||
1203 (str_has_prefix(str, "onmax(")) ||
1204 (str_has_prefix(str, "onchange("))) {
1205 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
1206 if (!attrs->action_str[attrs->n_actions]) {
1207 ret = -ENOMEM;
1208 return ret;
1209 }
1210 attrs->n_actions++;
1211 ret = 0;
1212 }
1213 return ret;
1214 }
1215
1216 static int parse_assignment(struct trace_array *tr,
1217 char *str, struct hist_trigger_attrs *attrs)
1218 {
1219 int len, ret = 0;
1220
1221 if ((len = str_has_prefix(str, "key=")) ||
1222 (len = str_has_prefix(str, "keys="))) {
1223 attrs->keys_str = kstrdup(str + len, GFP_KERNEL);
1224 if (!attrs->keys_str) {
1225 ret = -ENOMEM;
1226 goto out;
1227 }
1228 } else if ((len = str_has_prefix(str, "val=")) ||
1229 (len = str_has_prefix(str, "vals=")) ||
1230 (len = str_has_prefix(str, "values="))) {
1231 attrs->vals_str = kstrdup(str + len, GFP_KERNEL);
1232 if (!attrs->vals_str) {
1233 ret = -ENOMEM;
1234 goto out;
1235 }
1236 } else if ((len = str_has_prefix(str, "sort="))) {
1237 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL);
1238 if (!attrs->sort_key_str) {
1239 ret = -ENOMEM;
1240 goto out;
1241 }
1242 } else if (str_has_prefix(str, "name=")) {
1243 attrs->name = kstrdup(str, GFP_KERNEL);
1244 if (!attrs->name) {
1245 ret = -ENOMEM;
1246 goto out;
1247 }
1248 } else if ((len = str_has_prefix(str, "clock="))) {
1249 str += len;
1250
1251 str = strstrip(str);
1252 attrs->clock = kstrdup(str, GFP_KERNEL);
1253 if (!attrs->clock) {
1254 ret = -ENOMEM;
1255 goto out;
1256 }
1257 } else if ((len = str_has_prefix(str, "size="))) {
1258 int map_bits = parse_map_size(str + len);
1259
1260 if (map_bits < 0) {
1261 ret = map_bits;
1262 goto out;
1263 }
1264 attrs->map_bits = map_bits;
1265 } else {
1266 char *assignment;
1267
1268 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1269 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str));
1270 ret = -EINVAL;
1271 goto out;
1272 }
1273
1274 assignment = kstrdup(str, GFP_KERNEL);
1275 if (!assignment) {
1276 ret = -ENOMEM;
1277 goto out;
1278 }
1279
1280 attrs->assignment_str[attrs->n_assignments++] = assignment;
1281 }
1282 out:
1283 return ret;
1284 }
1285
1286 static struct hist_trigger_attrs *
1287 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
1288 {
1289 struct hist_trigger_attrs *attrs;
1290 int ret = 0;
1291
1292 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
1293 if (!attrs)
1294 return ERR_PTR(-ENOMEM);
1295
1296 while (trigger_str) {
1297 char *str = strsep(&trigger_str, ":");
1298 char *rhs;
1299
1300 rhs = strchr(str, '=');
1301 if (rhs) {
1302 if (!strlen(++rhs)) {
1303 ret = -EINVAL;
1304 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str));
1305 goto free;
1306 }
1307 ret = parse_assignment(tr, str, attrs);
1308 if (ret)
1309 goto free;
1310 } else if (strcmp(str, "pause") == 0)
1311 attrs->pause = true;
1312 else if ((strcmp(str, "cont") == 0) ||
1313 (strcmp(str, "continue") == 0))
1314 attrs->cont = true;
1315 else if (strcmp(str, "clear") == 0)
1316 attrs->clear = true;
1317 else {
1318 ret = parse_action(str, attrs);
1319 if (ret)
1320 goto free;
1321 }
1322 }
1323
1324 if (!attrs->keys_str) {
1325 ret = -EINVAL;
1326 goto free;
1327 }
1328
1329 if (!attrs->clock) {
1330 attrs->clock = kstrdup("global", GFP_KERNEL);
1331 if (!attrs->clock) {
1332 ret = -ENOMEM;
1333 goto free;
1334 }
1335 }
1336
1337 return attrs;
1338 free:
1339 destroy_hist_trigger_attrs(attrs);
1340
1341 return ERR_PTR(ret);
1342 }
1343
1344 static inline void save_comm(char *comm, struct task_struct *task)
1345 {
1346 if (!task->pid) {
1347 strcpy(comm, "<idle>");
1348 return;
1349 }
1350
1351 if (WARN_ON_ONCE(task->pid < 0)) {
1352 strcpy(comm, "<XXX>");
1353 return;
1354 }
1355
1356 strncpy(comm, task->comm, TASK_COMM_LEN);
1357 }
1358
1359 static void hist_elt_data_free(struct hist_elt_data *elt_data)
1360 {
1361 unsigned int i;
1362
1363 for (i = 0; i < SYNTH_FIELDS_MAX; i++)
1364 kfree(elt_data->field_var_str[i]);
1365
1366 kfree(elt_data->comm);
1367 kfree(elt_data);
1368 }
1369
1370 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1371 {
1372 struct hist_elt_data *elt_data = elt->private_data;
1373
1374 hist_elt_data_free(elt_data);
1375 }
1376
1377 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1378 {
1379 struct hist_trigger_data *hist_data = elt->map->private_data;
1380 unsigned int size = TASK_COMM_LEN;
1381 struct hist_elt_data *elt_data;
1382 struct hist_field *key_field;
1383 unsigned int i, n_str;
1384
1385 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
1386 if (!elt_data)
1387 return -ENOMEM;
1388
1389 for_each_hist_key_field(i, hist_data) {
1390 key_field = hist_data->fields[i];
1391
1392 if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
1393 elt_data->comm = kzalloc(size, GFP_KERNEL);
1394 if (!elt_data->comm) {
1395 kfree(elt_data);
1396 return -ENOMEM;
1397 }
1398 break;
1399 }
1400 }
1401
1402 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str +
1403 hist_data->n_var_str;
1404 if (n_str > SYNTH_FIELDS_MAX) {
1405 hist_elt_data_free(elt_data);
1406 return -EINVAL;
1407 }
1408
1409 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1));
1410
1411 size = STR_VAR_LEN_MAX;
1412
1413 for (i = 0; i < n_str; i++) {
1414 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
1415 if (!elt_data->field_var_str[i]) {
1416 hist_elt_data_free(elt_data);
1417 return -ENOMEM;
1418 }
1419 }
1420
1421 elt->private_data = elt_data;
1422
1423 return 0;
1424 }
1425
1426 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
1427 {
1428 struct hist_elt_data *elt_data = elt->private_data;
1429
1430 if (elt_data->comm)
1431 save_comm(elt_data->comm, current);
1432 }
1433
1434 static const struct tracing_map_ops hist_trigger_elt_data_ops = {
1435 .elt_alloc = hist_trigger_elt_data_alloc,
1436 .elt_free = hist_trigger_elt_data_free,
1437 .elt_init = hist_trigger_elt_data_init,
1438 };
1439
1440 static const char *get_hist_field_flags(struct hist_field *hist_field)
1441 {
1442 const char *flags_str = NULL;
1443
1444 if (hist_field->flags & HIST_FIELD_FL_HEX)
1445 flags_str = "hex";
1446 else if (hist_field->flags & HIST_FIELD_FL_SYM)
1447 flags_str = "sym";
1448 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
1449 flags_str = "sym-offset";
1450 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
1451 flags_str = "execname";
1452 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
1453 flags_str = "syscall";
1454 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
1455 flags_str = "log2";
1456 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1457 flags_str = "usecs";
1458
1459 return flags_str;
1460 }
1461
1462 static void expr_field_str(struct hist_field *field, char *expr)
1463 {
1464 if (field->flags & HIST_FIELD_FL_VAR_REF)
1465 strcat(expr, "$");
1466
1467 strcat(expr, hist_field_name(field, 0));
1468
1469 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
1470 const char *flags_str = get_hist_field_flags(field);
1471
1472 if (flags_str) {
1473 strcat(expr, ".");
1474 strcat(expr, flags_str);
1475 }
1476 }
1477 }
1478
1479 static char *expr_str(struct hist_field *field, unsigned int level)
1480 {
1481 char *expr;
1482
1483 if (level > 1)
1484 return NULL;
1485
1486 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
1487 if (!expr)
1488 return NULL;
1489
1490 if (!field->operands[0]) {
1491 expr_field_str(field, expr);
1492 return expr;
1493 }
1494
1495 if (field->operator == FIELD_OP_UNARY_MINUS) {
1496 char *subexpr;
1497
1498 strcat(expr, "-(");
1499 subexpr = expr_str(field->operands[0], ++level);
1500 if (!subexpr) {
1501 kfree(expr);
1502 return NULL;
1503 }
1504 strcat(expr, subexpr);
1505 strcat(expr, ")");
1506
1507 kfree(subexpr);
1508
1509 return expr;
1510 }
1511
1512 expr_field_str(field->operands[0], expr);
1513
1514 switch (field->operator) {
1515 case FIELD_OP_MINUS:
1516 strcat(expr, "-");
1517 break;
1518 case FIELD_OP_PLUS:
1519 strcat(expr, "+");
1520 break;
1521 default:
1522 kfree(expr);
1523 return NULL;
1524 }
1525
1526 expr_field_str(field->operands[1], expr);
1527
1528 return expr;
1529 }
1530
1531 static int contains_operator(char *str)
1532 {
1533 enum field_op_id field_op = FIELD_OP_NONE;
1534 char *op;
1535
1536 op = strpbrk(str, "+-");
1537 if (!op)
1538 return FIELD_OP_NONE;
1539
1540 switch (*op) {
1541 case '-':
1542 if (*str == '-')
1543 field_op = FIELD_OP_UNARY_MINUS;
1544 else
1545 field_op = FIELD_OP_MINUS;
1546 break;
1547 case '+':
1548 field_op = FIELD_OP_PLUS;
1549 break;
1550 default:
1551 break;
1552 }
1553
1554 return field_op;
1555 }
1556
1557 static void get_hist_field(struct hist_field *hist_field)
1558 {
1559 hist_field->ref++;
1560 }
1561
1562 static void __destroy_hist_field(struct hist_field *hist_field)
1563 {
1564 if (--hist_field->ref > 1)
1565 return;
1566
1567 kfree(hist_field->var.name);
1568 kfree(hist_field->name);
1569 kfree(hist_field->type);
1570
1571 kfree(hist_field->system);
1572 kfree(hist_field->event_name);
1573
1574 kfree(hist_field);
1575 }
1576
1577 static void destroy_hist_field(struct hist_field *hist_field,
1578 unsigned int level)
1579 {
1580 unsigned int i;
1581
1582 if (level > 3)
1583 return;
1584
1585 if (!hist_field)
1586 return;
1587
1588 if (hist_field->flags & HIST_FIELD_FL_VAR_REF)
1589 return; /* var refs will be destroyed separately */
1590
1591 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
1592 destroy_hist_field(hist_field->operands[i], level + 1);
1593
1594 __destroy_hist_field(hist_field);
1595 }
1596
1597 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
1598 struct ftrace_event_field *field,
1599 unsigned long flags,
1600 char *var_name)
1601 {
1602 struct hist_field *hist_field;
1603
1604 if (field && is_function_field(field))
1605 return NULL;
1606
1607 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
1608 if (!hist_field)
1609 return NULL;
1610
1611 hist_field->ref = 1;
1612
1613 hist_field->hist_data = hist_data;
1614
1615 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
1616 goto out; /* caller will populate */
1617
1618 if (flags & HIST_FIELD_FL_VAR_REF) {
1619 hist_field->fn = hist_field_var_ref;
1620 goto out;
1621 }
1622
1623 if (flags & HIST_FIELD_FL_HITCOUNT) {
1624 hist_field->fn = hist_field_counter;
1625 hist_field->size = sizeof(u64);
1626 hist_field->type = kstrdup("u64", GFP_KERNEL);
1627 if (!hist_field->type)
1628 goto free;
1629 goto out;
1630 }
1631
1632 if (flags & HIST_FIELD_FL_STACKTRACE) {
1633 hist_field->fn = hist_field_none;
1634 goto out;
1635 }
1636
1637 if (flags & HIST_FIELD_FL_LOG2) {
1638 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
1639 hist_field->fn = hist_field_log2;
1640 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
1641 hist_field->size = hist_field->operands[0]->size;
1642 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
1643 if (!hist_field->type)
1644 goto free;
1645 goto out;
1646 }
1647
1648 if (flags & HIST_FIELD_FL_TIMESTAMP) {
1649 hist_field->fn = hist_field_timestamp;
1650 hist_field->size = sizeof(u64);
1651 hist_field->type = kstrdup("u64", GFP_KERNEL);
1652 if (!hist_field->type)
1653 goto free;
1654 goto out;
1655 }
1656
1657 if (flags & HIST_FIELD_FL_CPU) {
1658 hist_field->fn = hist_field_cpu;
1659 hist_field->size = sizeof(int);
1660 hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
1661 if (!hist_field->type)
1662 goto free;
1663 goto out;
1664 }
1665
1666 if (WARN_ON_ONCE(!field))
1667 goto out;
1668
1669 if (is_string_field(field)) {
1670 flags |= HIST_FIELD_FL_STRING;
1671
1672 hist_field->size = MAX_FILTER_STR_VAL;
1673 hist_field->type = kstrdup(field->type, GFP_KERNEL);
1674 if (!hist_field->type)
1675 goto free;
1676
1677 if (field->filter_type == FILTER_STATIC_STRING)
1678 hist_field->fn = hist_field_string;
1679 else if (field->filter_type == FILTER_DYN_STRING)
1680 hist_field->fn = hist_field_dynstring;
1681 else
1682 hist_field->fn = hist_field_pstring;
1683 } else {
1684 hist_field->size = field->size;
1685 hist_field->is_signed = field->is_signed;
1686 hist_field->type = kstrdup(field->type, GFP_KERNEL);
1687 if (!hist_field->type)
1688 goto free;
1689
1690 hist_field->fn = select_value_fn(field->size,
1691 field->is_signed);
1692 if (!hist_field->fn) {
1693 destroy_hist_field(hist_field, 0);
1694 return NULL;
1695 }
1696 }
1697 out:
1698 hist_field->field = field;
1699 hist_field->flags = flags;
1700
1701 if (var_name) {
1702 hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
1703 if (!hist_field->var.name)
1704 goto free;
1705 }
1706
1707 return hist_field;
1708 free:
1709 destroy_hist_field(hist_field, 0);
1710 return NULL;
1711 }
1712
1713 static void destroy_hist_fields(struct hist_trigger_data *hist_data)
1714 {
1715 unsigned int i;
1716
1717 for (i = 0; i < HIST_FIELDS_MAX; i++) {
1718 if (hist_data->fields[i]) {
1719 destroy_hist_field(hist_data->fields[i], 0);
1720 hist_data->fields[i] = NULL;
1721 }
1722 }
1723
1724 for (i = 0; i < hist_data->n_var_refs; i++) {
1725 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF));
1726 __destroy_hist_field(hist_data->var_refs[i]);
1727 hist_data->var_refs[i] = NULL;
1728 }
1729 }
1730
1731 static int init_var_ref(struct hist_field *ref_field,
1732 struct hist_field *var_field,
1733 char *system, char *event_name)
1734 {
1735 int err = 0;
1736
1737 ref_field->var.idx = var_field->var.idx;
1738 ref_field->var.hist_data = var_field->hist_data;
1739 ref_field->size = var_field->size;
1740 ref_field->is_signed = var_field->is_signed;
1741 ref_field->flags |= var_field->flags &
1742 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
1743
1744 if (system) {
1745 ref_field->system = kstrdup(system, GFP_KERNEL);
1746 if (!ref_field->system)
1747 return -ENOMEM;
1748 }
1749
1750 if (event_name) {
1751 ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
1752 if (!ref_field->event_name) {
1753 err = -ENOMEM;
1754 goto free;
1755 }
1756 }
1757
1758 if (var_field->var.name) {
1759 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
1760 if (!ref_field->name) {
1761 err = -ENOMEM;
1762 goto free;
1763 }
1764 } else if (var_field->name) {
1765 ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
1766 if (!ref_field->name) {
1767 err = -ENOMEM;
1768 goto free;
1769 }
1770 }
1771
1772 ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
1773 if (!ref_field->type) {
1774 err = -ENOMEM;
1775 goto free;
1776 }
1777 out:
1778 return err;
1779 free:
1780 kfree(ref_field->system);
1781 kfree(ref_field->event_name);
1782 kfree(ref_field->name);
1783
1784 goto out;
1785 }
1786
1787 static int find_var_ref_idx(struct hist_trigger_data *hist_data,
1788 struct hist_field *var_field)
1789 {
1790 struct hist_field *ref_field;
1791 int i;
1792
1793 for (i = 0; i < hist_data->n_var_refs; i++) {
1794 ref_field = hist_data->var_refs[i];
1795 if (ref_field->var.idx == var_field->var.idx &&
1796 ref_field->var.hist_data == var_field->hist_data)
1797 return i;
1798 }
1799
1800 return -ENOENT;
1801 }
1802
1803 /**
1804 * create_var_ref - Create a variable reference and attach it to trigger
1805 * @hist_data: The trigger that will be referencing the variable
1806 * @var_field: The VAR field to create a reference to
1807 * @system: The optional system string
1808 * @event_name: The optional event_name string
1809 *
1810 * Given a variable hist_field, create a VAR_REF hist_field that
1811 * represents a reference to it.
1812 *
1813 * This function also adds the reference to the trigger that
1814 * now references the variable.
1815 *
1816 * Return: The VAR_REF field if successful, NULL if not
1817 */
1818 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
1819 struct hist_field *var_field,
1820 char *system, char *event_name)
1821 {
1822 unsigned long flags = HIST_FIELD_FL_VAR_REF;
1823 struct hist_field *ref_field;
1824 int i;
1825
1826 /* Check if the variable already exists */
1827 for (i = 0; i < hist_data->n_var_refs; i++) {
1828 ref_field = hist_data->var_refs[i];
1829 if (ref_field->var.idx == var_field->var.idx &&
1830 ref_field->var.hist_data == var_field->hist_data) {
1831 get_hist_field(ref_field);
1832 return ref_field;
1833 }
1834 }
1835
1836 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
1837 if (ref_field) {
1838 if (init_var_ref(ref_field, var_field, system, event_name)) {
1839 destroy_hist_field(ref_field, 0);
1840 return NULL;
1841 }
1842
1843 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
1844 ref_field->var_ref_idx = hist_data->n_var_refs++;
1845 }
1846
1847 return ref_field;
1848 }
1849
1850 static bool is_var_ref(char *var_name)
1851 {
1852 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
1853 return false;
1854
1855 return true;
1856 }
1857
1858 static char *field_name_from_var(struct hist_trigger_data *hist_data,
1859 char *var_name)
1860 {
1861 char *name, *field;
1862 unsigned int i;
1863
1864 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
1865 name = hist_data->attrs->var_defs.name[i];
1866
1867 if (strcmp(var_name, name) == 0) {
1868 field = hist_data->attrs->var_defs.expr[i];
1869 if (contains_operator(field) || is_var_ref(field))
1870 continue;
1871 return field;
1872 }
1873 }
1874
1875 return NULL;
1876 }
1877
1878 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
1879 char *system, char *event_name,
1880 char *var_name)
1881 {
1882 struct trace_event_call *call;
1883
1884 if (system && event_name) {
1885 call = hist_data->event_file->event_call;
1886
1887 if (strcmp(system, call->class->system) != 0)
1888 return NULL;
1889
1890 if (strcmp(event_name, trace_event_name(call)) != 0)
1891 return NULL;
1892 }
1893
1894 if (!!system != !!event_name)
1895 return NULL;
1896
1897 if (!is_var_ref(var_name))
1898 return NULL;
1899
1900 var_name++;
1901
1902 return field_name_from_var(hist_data, var_name);
1903 }
1904
1905 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
1906 char *system, char *event_name,
1907 char *var_name)
1908 {
1909 struct hist_field *var_field = NULL, *ref_field = NULL;
1910 struct trace_array *tr = hist_data->event_file->tr;
1911
1912 if (!is_var_ref(var_name))
1913 return NULL;
1914
1915 var_name++;
1916
1917 var_field = find_event_var(hist_data, system, event_name, var_name);
1918 if (var_field)
1919 ref_field = create_var_ref(hist_data, var_field,
1920 system, event_name);
1921
1922 if (!ref_field)
1923 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name));
1924
1925 return ref_field;
1926 }
1927
1928 static struct ftrace_event_field *
1929 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
1930 char *field_str, unsigned long *flags)
1931 {
1932 struct ftrace_event_field *field = NULL;
1933 char *field_name, *modifier, *str;
1934 struct trace_array *tr = file->tr;
1935
1936 modifier = str = kstrdup(field_str, GFP_KERNEL);
1937 if (!modifier)
1938 return ERR_PTR(-ENOMEM);
1939
1940 field_name = strsep(&modifier, ".");
1941 if (modifier) {
1942 if (strcmp(modifier, "hex") == 0)
1943 *flags |= HIST_FIELD_FL_HEX;
1944 else if (strcmp(modifier, "sym") == 0)
1945 *flags |= HIST_FIELD_FL_SYM;
1946 else if (strcmp(modifier, "sym-offset") == 0)
1947 *flags |= HIST_FIELD_FL_SYM_OFFSET;
1948 else if ((strcmp(modifier, "execname") == 0) &&
1949 (strcmp(field_name, "common_pid") == 0))
1950 *flags |= HIST_FIELD_FL_EXECNAME;
1951 else if (strcmp(modifier, "syscall") == 0)
1952 *flags |= HIST_FIELD_FL_SYSCALL;
1953 else if (strcmp(modifier, "log2") == 0)
1954 *flags |= HIST_FIELD_FL_LOG2;
1955 else if (strcmp(modifier, "usecs") == 0)
1956 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
1957 else {
1958 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
1959 field = ERR_PTR(-EINVAL);
1960 goto out;
1961 }
1962 }
1963
1964 if (strcmp(field_name, "common_timestamp") == 0) {
1965 *flags |= HIST_FIELD_FL_TIMESTAMP;
1966 hist_data->enable_timestamps = true;
1967 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1968 hist_data->attrs->ts_in_usecs = true;
1969 } else if (strcmp(field_name, "cpu") == 0)
1970 *flags |= HIST_FIELD_FL_CPU;
1971 else {
1972 field = trace_find_event_field(file->event_call, field_name);
1973 if (!field || !field->size) {
1974 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, errpos(field_name));
1975 field = ERR_PTR(-EINVAL);
1976 goto out;
1977 }
1978 }
1979 out:
1980 kfree(str);
1981
1982 return field;
1983 }
1984
1985 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
1986 struct hist_field *var_ref,
1987 char *var_name)
1988 {
1989 struct hist_field *alias = NULL;
1990 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
1991
1992 alias = create_hist_field(hist_data, NULL, flags, var_name);
1993 if (!alias)
1994 return NULL;
1995
1996 alias->fn = var_ref->fn;
1997 alias->operands[0] = var_ref;
1998
1999 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2000 destroy_hist_field(alias, 0);
2001 return NULL;
2002 }
2003
2004 alias->var_ref_idx = var_ref->var_ref_idx;
2005
2006 return alias;
2007 }
2008
2009 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2010 struct trace_event_file *file, char *str,
2011 unsigned long *flags, char *var_name)
2012 {
2013 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2014 struct ftrace_event_field *field = NULL;
2015 struct hist_field *hist_field = NULL;
2016 int ret = 0;
2017
2018 s = strchr(str, '.');
2019 if (s) {
2020 s = strchr(++s, '.');
2021 if (s) {
2022 ref_system = strsep(&str, ".");
2023 if (!str) {
2024 ret = -EINVAL;
2025 goto out;
2026 }
2027 ref_event = strsep(&str, ".");
2028 if (!str) {
2029 ret = -EINVAL;
2030 goto out;
2031 }
2032 ref_var = str;
2033 }
2034 }
2035
2036 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2037 if (!s) {
2038 hist_field = parse_var_ref(hist_data, ref_system,
2039 ref_event, ref_var);
2040 if (hist_field) {
2041 if (var_name) {
2042 hist_field = create_alias(hist_data, hist_field, var_name);
2043 if (!hist_field) {
2044 ret = -ENOMEM;
2045 goto out;
2046 }
2047 }
2048 return hist_field;
2049 }
2050 } else
2051 str = s;
2052
2053 field = parse_field(hist_data, file, str, flags);
2054 if (IS_ERR(field)) {
2055 ret = PTR_ERR(field);
2056 goto out;
2057 }
2058
2059 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2060 if (!hist_field) {
2061 ret = -ENOMEM;
2062 goto out;
2063 }
2064
2065 return hist_field;
2066 out:
2067 return ERR_PTR(ret);
2068 }
2069
2070 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2071 struct trace_event_file *file,
2072 char *str, unsigned long flags,
2073 char *var_name, unsigned int level);
2074
2075 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2076 struct trace_event_file *file,
2077 char *str, unsigned long flags,
2078 char *var_name, unsigned int level)
2079 {
2080 struct hist_field *operand1, *expr = NULL;
2081 unsigned long operand_flags;
2082 int ret = 0;
2083 char *s;
2084
2085 /* we support only -(xxx) i.e. explicit parens required */
2086
2087 if (level > 3) {
2088 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2089 ret = -EINVAL;
2090 goto free;
2091 }
2092
2093 str++; /* skip leading '-' */
2094
2095 s = strchr(str, '(');
2096 if (s)
2097 str++;
2098 else {
2099 ret = -EINVAL;
2100 goto free;
2101 }
2102
2103 s = strrchr(str, ')');
2104 if (s)
2105 *s = '\0';
2106 else {
2107 ret = -EINVAL; /* no closing ')' */
2108 goto free;
2109 }
2110
2111 flags |= HIST_FIELD_FL_EXPR;
2112 expr = create_hist_field(hist_data, NULL, flags, var_name);
2113 if (!expr) {
2114 ret = -ENOMEM;
2115 goto free;
2116 }
2117
2118 operand_flags = 0;
2119 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2120 if (IS_ERR(operand1)) {
2121 ret = PTR_ERR(operand1);
2122 goto free;
2123 }
2124
2125 expr->flags |= operand1->flags &
2126 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2127 expr->fn = hist_field_unary_minus;
2128 expr->operands[0] = operand1;
2129 expr->operator = FIELD_OP_UNARY_MINUS;
2130 expr->name = expr_str(expr, 0);
2131 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2132 if (!expr->type) {
2133 ret = -ENOMEM;
2134 goto free;
2135 }
2136
2137 return expr;
2138 free:
2139 destroy_hist_field(expr, 0);
2140 return ERR_PTR(ret);
2141 }
2142
2143 static int check_expr_operands(struct trace_array *tr,
2144 struct hist_field *operand1,
2145 struct hist_field *operand2)
2146 {
2147 unsigned long operand1_flags = operand1->flags;
2148 unsigned long operand2_flags = operand2->flags;
2149
2150 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2151 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2152 struct hist_field *var;
2153
2154 var = find_var_field(operand1->var.hist_data, operand1->name);
2155 if (!var)
2156 return -EINVAL;
2157 operand1_flags = var->flags;
2158 }
2159
2160 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2161 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2162 struct hist_field *var;
2163
2164 var = find_var_field(operand2->var.hist_data, operand2->name);
2165 if (!var)
2166 return -EINVAL;
2167 operand2_flags = var->flags;
2168 }
2169
2170 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2171 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2172 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0);
2173 return -EINVAL;
2174 }
2175
2176 return 0;
2177 }
2178
2179 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2180 struct trace_event_file *file,
2181 char *str, unsigned long flags,
2182 char *var_name, unsigned int level)
2183 {
2184 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2185 unsigned long operand_flags;
2186 int field_op, ret = -EINVAL;
2187 char *sep, *operand1_str;
2188
2189 if (level > 3) {
2190 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2191 return ERR_PTR(-EINVAL);
2192 }
2193
2194 field_op = contains_operator(str);
2195
2196 if (field_op == FIELD_OP_NONE)
2197 return parse_atom(hist_data, file, str, &flags, var_name);
2198
2199 if (field_op == FIELD_OP_UNARY_MINUS)
2200 return parse_unary(hist_data, file, str, flags, var_name, ++level);
2201
2202 switch (field_op) {
2203 case FIELD_OP_MINUS:
2204 sep = "-";
2205 break;
2206 case FIELD_OP_PLUS:
2207 sep = "+";
2208 break;
2209 default:
2210 goto free;
2211 }
2212
2213 operand1_str = strsep(&str, sep);
2214 if (!operand1_str || !str)
2215 goto free;
2216
2217 operand_flags = 0;
2218 operand1 = parse_atom(hist_data, file, operand1_str,
2219 &operand_flags, NULL);
2220 if (IS_ERR(operand1)) {
2221 ret = PTR_ERR(operand1);
2222 operand1 = NULL;
2223 goto free;
2224 }
2225
2226 /* rest of string could be another expression e.g. b+c in a+b+c */
2227 operand_flags = 0;
2228 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2229 if (IS_ERR(operand2)) {
2230 ret = PTR_ERR(operand2);
2231 operand2 = NULL;
2232 goto free;
2233 }
2234
2235 ret = check_expr_operands(file->tr, operand1, operand2);
2236 if (ret)
2237 goto free;
2238
2239 flags |= HIST_FIELD_FL_EXPR;
2240
2241 flags |= operand1->flags &
2242 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2243
2244 expr = create_hist_field(hist_data, NULL, flags, var_name);
2245 if (!expr) {
2246 ret = -ENOMEM;
2247 goto free;
2248 }
2249
2250 operand1->read_once = true;
2251 operand2->read_once = true;
2252
2253 expr->operands[0] = operand1;
2254 expr->operands[1] = operand2;
2255 expr->operator = field_op;
2256 expr->name = expr_str(expr, 0);
2257 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2258 if (!expr->type) {
2259 ret = -ENOMEM;
2260 goto free;
2261 }
2262
2263 switch (field_op) {
2264 case FIELD_OP_MINUS:
2265 expr->fn = hist_field_minus;
2266 break;
2267 case FIELD_OP_PLUS:
2268 expr->fn = hist_field_plus;
2269 break;
2270 default:
2271 ret = -EINVAL;
2272 goto free;
2273 }
2274
2275 return expr;
2276 free:
2277 destroy_hist_field(operand1, 0);
2278 destroy_hist_field(operand2, 0);
2279 destroy_hist_field(expr, 0);
2280
2281 return ERR_PTR(ret);
2282 }
2283
2284 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2285 struct trace_event_file *file)
2286 {
2287 struct event_trigger_data *test;
2288
2289 lockdep_assert_held(&event_mutex);
2290
2291 list_for_each_entry(test, &file->triggers, list) {
2292 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2293 if (test->private_data == hist_data)
2294 return test->filter_str;
2295 }
2296 }
2297
2298 return NULL;
2299 }
2300
2301 static struct event_command trigger_hist_cmd;
2302 static int event_hist_trigger_func(struct event_command *cmd_ops,
2303 struct trace_event_file *file,
2304 char *glob, char *cmd, char *param);
2305
2306 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2307 struct hist_trigger_data *hist_data,
2308 unsigned int n_keys)
2309 {
2310 struct hist_field *target_hist_field, *hist_field;
2311 unsigned int n, i, j;
2312
2313 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2314 return false;
2315
2316 i = hist_data->n_vals;
2317 j = target_hist_data->n_vals;
2318
2319 for (n = 0; n < n_keys; n++) {
2320 hist_field = hist_data->fields[i + n];
2321 target_hist_field = target_hist_data->fields[j + n];
2322
2323 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2324 return false;
2325 if (hist_field->size != target_hist_field->size)
2326 return false;
2327 if (hist_field->is_signed != target_hist_field->is_signed)
2328 return false;
2329 }
2330
2331 return true;
2332 }
2333
2334 static struct hist_trigger_data *
2335 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2336 struct trace_event_file *file)
2337 {
2338 struct hist_trigger_data *hist_data;
2339 struct event_trigger_data *test;
2340 unsigned int n_keys;
2341
2342 lockdep_assert_held(&event_mutex);
2343
2344 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2345
2346 list_for_each_entry(test, &file->triggers, list) {
2347 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2348 hist_data = test->private_data;
2349
2350 if (compatible_keys(target_hist_data, hist_data, n_keys))
2351 return hist_data;
2352 }
2353 }
2354
2355 return NULL;
2356 }
2357
2358 static struct trace_event_file *event_file(struct trace_array *tr,
2359 char *system, char *event_name)
2360 {
2361 struct trace_event_file *file;
2362
2363 file = __find_event_file(tr, system, event_name);
2364 if (!file)
2365 return ERR_PTR(-EINVAL);
2366
2367 return file;
2368 }
2369
2370 static struct hist_field *
2371 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2372 char *system, char *event_name, char *field_name)
2373 {
2374 struct hist_field *event_var;
2375 char *synthetic_name;
2376
2377 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2378 if (!synthetic_name)
2379 return ERR_PTR(-ENOMEM);
2380
2381 strcpy(synthetic_name, "synthetic_");
2382 strcat(synthetic_name, field_name);
2383
2384 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2385
2386 kfree(synthetic_name);
2387
2388 return event_var;
2389 }
2390
2391 /**
2392 * create_field_var_hist - Automatically create a histogram and var for a field
2393 * @target_hist_data: The target hist trigger
2394 * @subsys_name: Optional subsystem name
2395 * @event_name: Optional event name
2396 * @field_name: The name of the field (and the resulting variable)
2397 *
2398 * Hist trigger actions fetch data from variables, not directly from
2399 * events. However, for convenience, users are allowed to directly
2400 * specify an event field in an action, which will be automatically
2401 * converted into a variable on their behalf.
2402
2403 * If a user specifies a field on an event that isn't the event the
2404 * histogram currently being defined (the target event histogram), the
2405 * only way that can be accomplished is if a new hist trigger is
2406 * created and the field variable defined on that.
2407 *
2408 * This function creates a new histogram compatible with the target
2409 * event (meaning a histogram with the same key as the target
2410 * histogram), and creates a variable for the specified field, but
2411 * with 'synthetic_' prepended to the variable name in order to avoid
2412 * collision with normal field variables.
2413 *
2414 * Return: The variable created for the field.
2415 */
2416 static struct hist_field *
2417 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2418 char *subsys_name, char *event_name, char *field_name)
2419 {
2420 struct trace_array *tr = target_hist_data->event_file->tr;
2421 struct hist_field *event_var = ERR_PTR(-EINVAL);
2422 struct hist_trigger_data *hist_data;
2423 unsigned int i, n, first = true;
2424 struct field_var_hist *var_hist;
2425 struct trace_event_file *file;
2426 struct hist_field *key_field;
2427 char *saved_filter;
2428 char *cmd;
2429 int ret;
2430
2431 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2432 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2433 return ERR_PTR(-EINVAL);
2434 }
2435
2436 file = event_file(tr, subsys_name, event_name);
2437
2438 if (IS_ERR(file)) {
2439 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name));
2440 ret = PTR_ERR(file);
2441 return ERR_PTR(ret);
2442 }
2443
2444 /*
2445 * Look for a histogram compatible with target. We'll use the
2446 * found histogram specification to create a new matching
2447 * histogram with our variable on it. target_hist_data is not
2448 * yet a registered histogram so we can't use that.
2449 */
2450 hist_data = find_compatible_hist(target_hist_data, file);
2451 if (!hist_data) {
2452 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name));
2453 return ERR_PTR(-EINVAL);
2454 }
2455
2456 /* See if a synthetic field variable has already been created */
2457 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2458 event_name, field_name);
2459 if (!IS_ERR_OR_NULL(event_var))
2460 return event_var;
2461
2462 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2463 if (!var_hist)
2464 return ERR_PTR(-ENOMEM);
2465
2466 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2467 if (!cmd) {
2468 kfree(var_hist);
2469 return ERR_PTR(-ENOMEM);
2470 }
2471
2472 /* Use the same keys as the compatible histogram */
2473 strcat(cmd, "keys=");
2474
2475 for_each_hist_key_field(i, hist_data) {
2476 key_field = hist_data->fields[i];
2477 if (!first)
2478 strcat(cmd, ",");
2479 strcat(cmd, key_field->field->name);
2480 first = false;
2481 }
2482
2483 /* Create the synthetic field variable specification */
2484 strcat(cmd, ":synthetic_");
2485 strcat(cmd, field_name);
2486 strcat(cmd, "=");
2487 strcat(cmd, field_name);
2488
2489 /* Use the same filter as the compatible histogram */
2490 saved_filter = find_trigger_filter(hist_data, file);
2491 if (saved_filter) {
2492 strcat(cmd, " if ");
2493 strcat(cmd, saved_filter);
2494 }
2495
2496 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
2497 if (!var_hist->cmd) {
2498 kfree(cmd);
2499 kfree(var_hist);
2500 return ERR_PTR(-ENOMEM);
2501 }
2502
2503 /* Save the compatible histogram information */
2504 var_hist->hist_data = hist_data;
2505
2506 /* Create the new histogram with our variable */
2507 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
2508 "", "hist", cmd);
2509 if (ret) {
2510 kfree(cmd);
2511 kfree(var_hist->cmd);
2512 kfree(var_hist);
2513 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name));
2514 return ERR_PTR(ret);
2515 }
2516
2517 kfree(cmd);
2518
2519 /* If we can't find the variable, something went wrong */
2520 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2521 event_name, field_name);
2522 if (IS_ERR_OR_NULL(event_var)) {
2523 kfree(var_hist->cmd);
2524 kfree(var_hist);
2525 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name));
2526 return ERR_PTR(-EINVAL);
2527 }
2528
2529 n = target_hist_data->n_field_var_hists;
2530 target_hist_data->field_var_hists[n] = var_hist;
2531 target_hist_data->n_field_var_hists++;
2532
2533 return event_var;
2534 }
2535
2536 static struct hist_field *
2537 find_target_event_var(struct hist_trigger_data *hist_data,
2538 char *subsys_name, char *event_name, char *var_name)
2539 {
2540 struct trace_event_file *file = hist_data->event_file;
2541 struct hist_field *hist_field = NULL;
2542
2543 if (subsys_name) {
2544 struct trace_event_call *call;
2545
2546 if (!event_name)
2547 return NULL;
2548
2549 call = file->event_call;
2550
2551 if (strcmp(subsys_name, call->class->system) != 0)
2552 return NULL;
2553
2554 if (strcmp(event_name, trace_event_name(call)) != 0)
2555 return NULL;
2556 }
2557
2558 hist_field = find_var_field(hist_data, var_name);
2559
2560 return hist_field;
2561 }
2562
2563 static inline void __update_field_vars(struct tracing_map_elt *elt,
2564 struct ring_buffer_event *rbe,
2565 void *rec,
2566 struct field_var **field_vars,
2567 unsigned int n_field_vars,
2568 unsigned int field_var_str_start)
2569 {
2570 struct hist_elt_data *elt_data = elt->private_data;
2571 unsigned int i, j, var_idx;
2572 u64 var_val;
2573
2574 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
2575 struct field_var *field_var = field_vars[i];
2576 struct hist_field *var = field_var->var;
2577 struct hist_field *val = field_var->val;
2578
2579 var_val = val->fn(val, elt, rbe, rec);
2580 var_idx = var->var.idx;
2581
2582 if (val->flags & HIST_FIELD_FL_STRING) {
2583 char *str = elt_data->field_var_str[j++];
2584 char *val_str = (char *)(uintptr_t)var_val;
2585
2586 strscpy(str, val_str, STR_VAR_LEN_MAX);
2587 var_val = (u64)(uintptr_t)str;
2588 }
2589 tracing_map_set_var(elt, var_idx, var_val);
2590 }
2591 }
2592
2593 static void update_field_vars(struct hist_trigger_data *hist_data,
2594 struct tracing_map_elt *elt,
2595 struct ring_buffer_event *rbe,
2596 void *rec)
2597 {
2598 __update_field_vars(elt, rbe, rec, hist_data->field_vars,
2599 hist_data->n_field_vars, 0);
2600 }
2601
2602 static void save_track_data_vars(struct hist_trigger_data *hist_data,
2603 struct tracing_map_elt *elt, void *rec,
2604 struct ring_buffer_event *rbe, void *key,
2605 struct action_data *data, u64 *var_ref_vals)
2606 {
2607 __update_field_vars(elt, rbe, rec, hist_data->save_vars,
2608 hist_data->n_save_vars, hist_data->n_field_var_str);
2609 }
2610
2611 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
2612 struct trace_event_file *file,
2613 char *name, int size, const char *type)
2614 {
2615 struct hist_field *var;
2616 int idx;
2617
2618 if (find_var(hist_data, file, name) && !hist_data->remove) {
2619 var = ERR_PTR(-EINVAL);
2620 goto out;
2621 }
2622
2623 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
2624 if (!var) {
2625 var = ERR_PTR(-ENOMEM);
2626 goto out;
2627 }
2628
2629 idx = tracing_map_add_var(hist_data->map);
2630 if (idx < 0) {
2631 kfree(var);
2632 var = ERR_PTR(-EINVAL);
2633 goto out;
2634 }
2635
2636 var->ref = 1;
2637 var->flags = HIST_FIELD_FL_VAR;
2638 var->var.idx = idx;
2639 var->var.hist_data = var->hist_data = hist_data;
2640 var->size = size;
2641 var->var.name = kstrdup(name, GFP_KERNEL);
2642 var->type = kstrdup(type, GFP_KERNEL);
2643 if (!var->var.name || !var->type) {
2644 kfree(var->var.name);
2645 kfree(var->type);
2646 kfree(var);
2647 var = ERR_PTR(-ENOMEM);
2648 }
2649 out:
2650 return var;
2651 }
2652
2653 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
2654 struct trace_event_file *file,
2655 char *field_name)
2656 {
2657 struct hist_field *val = NULL, *var = NULL;
2658 unsigned long flags = HIST_FIELD_FL_VAR;
2659 struct trace_array *tr = file->tr;
2660 struct field_var *field_var;
2661 int ret = 0;
2662
2663 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
2664 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2665 ret = -EINVAL;
2666 goto err;
2667 }
2668
2669 val = parse_atom(hist_data, file, field_name, &flags, NULL);
2670 if (IS_ERR(val)) {
2671 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name));
2672 ret = PTR_ERR(val);
2673 goto err;
2674 }
2675
2676 var = create_var(hist_data, file, field_name, val->size, val->type);
2677 if (IS_ERR(var)) {
2678 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name));
2679 kfree(val);
2680 ret = PTR_ERR(var);
2681 goto err;
2682 }
2683
2684 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
2685 if (!field_var) {
2686 kfree(val);
2687 kfree(var);
2688 ret = -ENOMEM;
2689 goto err;
2690 }
2691
2692 field_var->var = var;
2693 field_var->val = val;
2694 out:
2695 return field_var;
2696 err:
2697 field_var = ERR_PTR(ret);
2698 goto out;
2699 }
2700
2701 /**
2702 * create_target_field_var - Automatically create a variable for a field
2703 * @target_hist_data: The target hist trigger
2704 * @subsys_name: Optional subsystem name
2705 * @event_name: Optional event name
2706 * @var_name: The name of the field (and the resulting variable)
2707 *
2708 * Hist trigger actions fetch data from variables, not directly from
2709 * events. However, for convenience, users are allowed to directly
2710 * specify an event field in an action, which will be automatically
2711 * converted into a variable on their behalf.
2712
2713 * This function creates a field variable with the name var_name on
2714 * the hist trigger currently being defined on the target event. If
2715 * subsys_name and event_name are specified, this function simply
2716 * verifies that they do in fact match the target event subsystem and
2717 * event name.
2718 *
2719 * Return: The variable created for the field.
2720 */
2721 static struct field_var *
2722 create_target_field_var(struct hist_trigger_data *target_hist_data,
2723 char *subsys_name, char *event_name, char *var_name)
2724 {
2725 struct trace_event_file *file = target_hist_data->event_file;
2726
2727 if (subsys_name) {
2728 struct trace_event_call *call;
2729
2730 if (!event_name)
2731 return NULL;
2732
2733 call = file->event_call;
2734
2735 if (strcmp(subsys_name, call->class->system) != 0)
2736 return NULL;
2737
2738 if (strcmp(event_name, trace_event_name(call)) != 0)
2739 return NULL;
2740 }
2741
2742 return create_field_var(target_hist_data, file, var_name);
2743 }
2744
2745 static bool check_track_val_max(u64 track_val, u64 var_val)
2746 {
2747 if (var_val <= track_val)
2748 return false;
2749
2750 return true;
2751 }
2752
2753 static bool check_track_val_changed(u64 track_val, u64 var_val)
2754 {
2755 if (var_val == track_val)
2756 return false;
2757
2758 return true;
2759 }
2760
2761 static u64 get_track_val(struct hist_trigger_data *hist_data,
2762 struct tracing_map_elt *elt,
2763 struct action_data *data)
2764 {
2765 unsigned int track_var_idx = data->track_data.track_var->var.idx;
2766 u64 track_val;
2767
2768 track_val = tracing_map_read_var(elt, track_var_idx);
2769
2770 return track_val;
2771 }
2772
2773 static void save_track_val(struct hist_trigger_data *hist_data,
2774 struct tracing_map_elt *elt,
2775 struct action_data *data, u64 var_val)
2776 {
2777 unsigned int track_var_idx = data->track_data.track_var->var.idx;
2778
2779 tracing_map_set_var(elt, track_var_idx, var_val);
2780 }
2781
2782 static void save_track_data(struct hist_trigger_data *hist_data,
2783 struct tracing_map_elt *elt, void *rec,
2784 struct ring_buffer_event *rbe, void *key,
2785 struct action_data *data, u64 *var_ref_vals)
2786 {
2787 if (data->track_data.save_data)
2788 data->track_data.save_data(hist_data, elt, rec, rbe, key, data, var_ref_vals);
2789 }
2790
2791 static bool check_track_val(struct tracing_map_elt *elt,
2792 struct action_data *data,
2793 u64 var_val)
2794 {
2795 struct hist_trigger_data *hist_data;
2796 u64 track_val;
2797
2798 hist_data = data->track_data.track_var->hist_data;
2799 track_val = get_track_val(hist_data, elt, data);
2800
2801 return data->track_data.check_val(track_val, var_val);
2802 }
2803
2804 #ifdef CONFIG_TRACER_SNAPSHOT
2805 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
2806 {
2807 /* called with tr->max_lock held */
2808 struct track_data *track_data = tr->cond_snapshot->cond_data;
2809 struct hist_elt_data *elt_data, *track_elt_data;
2810 struct snapshot_context *context = cond_data;
2811 struct action_data *action;
2812 u64 track_val;
2813
2814 if (!track_data)
2815 return false;
2816
2817 action = track_data->action_data;
2818
2819 track_val = get_track_val(track_data->hist_data, context->elt,
2820 track_data->action_data);
2821
2822 if (!action->track_data.check_val(track_data->track_val, track_val))
2823 return false;
2824
2825 track_data->track_val = track_val;
2826 memcpy(track_data->key, context->key, track_data->key_len);
2827
2828 elt_data = context->elt->private_data;
2829 track_elt_data = track_data->elt.private_data;
2830 if (elt_data->comm)
2831 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN);
2832
2833 track_data->updated = true;
2834
2835 return true;
2836 }
2837
2838 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
2839 struct tracing_map_elt *elt, void *rec,
2840 struct ring_buffer_event *rbe, void *key,
2841 struct action_data *data,
2842 u64 *var_ref_vals)
2843 {
2844 struct trace_event_file *file = hist_data->event_file;
2845 struct snapshot_context context;
2846
2847 context.elt = elt;
2848 context.key = key;
2849
2850 tracing_snapshot_cond(file->tr, &context);
2851 }
2852
2853 static void hist_trigger_print_key(struct seq_file *m,
2854 struct hist_trigger_data *hist_data,
2855 void *key,
2856 struct tracing_map_elt *elt);
2857
2858 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
2859 {
2860 unsigned int i;
2861
2862 if (!hist_data->n_actions)
2863 return NULL;
2864
2865 for (i = 0; i < hist_data->n_actions; i++) {
2866 struct action_data *data = hist_data->actions[i];
2867
2868 if (data->action == ACTION_SNAPSHOT)
2869 return data;
2870 }
2871
2872 return NULL;
2873 }
2874
2875 static void track_data_snapshot_print(struct seq_file *m,
2876 struct hist_trigger_data *hist_data)
2877 {
2878 struct trace_event_file *file = hist_data->event_file;
2879 struct track_data *track_data;
2880 struct action_data *action;
2881
2882 track_data = tracing_cond_snapshot_data(file->tr);
2883 if (!track_data)
2884 return;
2885
2886 if (!track_data->updated)
2887 return;
2888
2889 action = snapshot_action(hist_data);
2890 if (!action)
2891 return;
2892
2893 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n");
2894 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu",
2895 action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
2896 action->track_data.var_str, track_data->track_val);
2897
2898 seq_puts(m, "\ttriggered by event with key: ");
2899 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt);
2900 seq_putc(m, '\n');
2901 }
2902 #else
2903 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
2904 {
2905 return false;
2906 }
2907 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
2908 struct tracing_map_elt *elt, void *rec,
2909 struct ring_buffer_event *rbe, void *key,
2910 struct action_data *data,
2911 u64 *var_ref_vals) {}
2912 static void track_data_snapshot_print(struct seq_file *m,
2913 struct hist_trigger_data *hist_data) {}
2914 #endif /* CONFIG_TRACER_SNAPSHOT */
2915
2916 static void track_data_print(struct seq_file *m,
2917 struct hist_trigger_data *hist_data,
2918 struct tracing_map_elt *elt,
2919 struct action_data *data)
2920 {
2921 u64 track_val = get_track_val(hist_data, elt, data);
2922 unsigned int i, save_var_idx;
2923
2924 if (data->handler == HANDLER_ONMAX)
2925 seq_printf(m, "\n\tmax: %10llu", track_val);
2926 else if (data->handler == HANDLER_ONCHANGE)
2927 seq_printf(m, "\n\tchanged: %10llu", track_val);
2928
2929 if (data->action == ACTION_SNAPSHOT)
2930 return;
2931
2932 for (i = 0; i < hist_data->n_save_vars; i++) {
2933 struct hist_field *save_val = hist_data->save_vars[i]->val;
2934 struct hist_field *save_var = hist_data->save_vars[i]->var;
2935 u64 val;
2936
2937 save_var_idx = save_var->var.idx;
2938
2939 val = tracing_map_read_var(elt, save_var_idx);
2940
2941 if (save_val->flags & HIST_FIELD_FL_STRING) {
2942 seq_printf(m, " %s: %-32s", save_var->var.name,
2943 (char *)(uintptr_t)(val));
2944 } else
2945 seq_printf(m, " %s: %10llu", save_var->var.name, val);
2946 }
2947 }
2948
2949 static void ontrack_action(struct hist_trigger_data *hist_data,
2950 struct tracing_map_elt *elt, void *rec,
2951 struct ring_buffer_event *rbe, void *key,
2952 struct action_data *data, u64 *var_ref_vals)
2953 {
2954 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx];
2955
2956 if (check_track_val(elt, data, var_val)) {
2957 save_track_val(hist_data, elt, data, var_val);
2958 save_track_data(hist_data, elt, rec, rbe, key, data, var_ref_vals);
2959 }
2960 }
2961
2962 static void action_data_destroy(struct action_data *data)
2963 {
2964 unsigned int i;
2965
2966 lockdep_assert_held(&event_mutex);
2967
2968 kfree(data->action_name);
2969
2970 for (i = 0; i < data->n_params; i++)
2971 kfree(data->params[i]);
2972
2973 if (data->synth_event)
2974 data->synth_event->ref--;
2975
2976 kfree(data->synth_event_name);
2977
2978 kfree(data);
2979 }
2980
2981 static void track_data_destroy(struct hist_trigger_data *hist_data,
2982 struct action_data *data)
2983 {
2984 struct trace_event_file *file = hist_data->event_file;
2985
2986 destroy_hist_field(data->track_data.track_var, 0);
2987
2988 if (data->action == ACTION_SNAPSHOT) {
2989 struct track_data *track_data;
2990
2991 track_data = tracing_cond_snapshot_data(file->tr);
2992 if (track_data && track_data->hist_data == hist_data) {
2993 tracing_snapshot_cond_disable(file->tr);
2994 track_data_free(track_data);
2995 }
2996 }
2997
2998 kfree(data->track_data.var_str);
2999
3000 action_data_destroy(data);
3001 }
3002
3003 static int action_create(struct hist_trigger_data *hist_data,
3004 struct action_data *data);
3005
3006 static int track_data_create(struct hist_trigger_data *hist_data,
3007 struct action_data *data)
3008 {
3009 struct hist_field *var_field, *ref_field, *track_var = NULL;
3010 struct trace_event_file *file = hist_data->event_file;
3011 struct trace_array *tr = file->tr;
3012 char *track_data_var_str;
3013 int ret = 0;
3014
3015 track_data_var_str = data->track_data.var_str;
3016 if (track_data_var_str[0] != '$') {
3017 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str));
3018 return -EINVAL;
3019 }
3020 track_data_var_str++;
3021
3022 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str);
3023 if (!var_field) {
3024 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str));
3025 return -EINVAL;
3026 }
3027
3028 ref_field = create_var_ref(hist_data, var_field, NULL, NULL);
3029 if (!ref_field)
3030 return -ENOMEM;
3031
3032 data->track_data.var_ref = ref_field;
3033
3034 if (data->handler == HANDLER_ONMAX)
3035 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64");
3036 if (IS_ERR(track_var)) {
3037 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3038 ret = PTR_ERR(track_var);
3039 goto out;
3040 }
3041
3042 if (data->handler == HANDLER_ONCHANGE)
3043 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64");
3044 if (IS_ERR(track_var)) {
3045 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3046 ret = PTR_ERR(track_var);
3047 goto out;
3048 }
3049 data->track_data.track_var = track_var;
3050
3051 ret = action_create(hist_data, data);
3052 out:
3053 return ret;
3054 }
3055
3056 static int parse_action_params(struct trace_array *tr, char *params,
3057 struct action_data *data)
3058 {
3059 char *param, *saved_param;
3060 bool first_param = true;
3061 int ret = 0;
3062
3063 while (params) {
3064 if (data->n_params >= SYNTH_FIELDS_MAX) {
3065 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0);
3066 goto out;
3067 }
3068
3069 param = strsep(&params, ",");
3070 if (!param) {
3071 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0);
3072 ret = -EINVAL;
3073 goto out;
3074 }
3075
3076 param = strstrip(param);
3077 if (strlen(param) < 2) {
3078 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param));
3079 ret = -EINVAL;
3080 goto out;
3081 }
3082
3083 saved_param = kstrdup(param, GFP_KERNEL);
3084 if (!saved_param) {
3085 ret = -ENOMEM;
3086 goto out;
3087 }
3088
3089 if (first_param && data->use_trace_keyword) {
3090 data->synth_event_name = saved_param;
3091 first_param = false;
3092 continue;
3093 }
3094 first_param = false;
3095
3096 data->params[data->n_params++] = saved_param;
3097 }
3098 out:
3099 return ret;
3100 }
3101
3102 static int action_parse(struct trace_array *tr, char *str, struct action_data *data,
3103 enum handler_id handler)
3104 {
3105 char *action_name;
3106 int ret = 0;
3107
3108 strsep(&str, ".");
3109 if (!str) {
3110 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3111 ret = -EINVAL;
3112 goto out;
3113 }
3114
3115 action_name = strsep(&str, "(");
3116 if (!action_name || !str) {
3117 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3118 ret = -EINVAL;
3119 goto out;
3120 }
3121
3122 if (str_has_prefix(action_name, "save")) {
3123 char *params = strsep(&str, ")");
3124
3125 if (!params) {
3126 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0);
3127 ret = -EINVAL;
3128 goto out;
3129 }
3130
3131 ret = parse_action_params(tr, params, data);
3132 if (ret)
3133 goto out;
3134
3135 if (handler == HANDLER_ONMAX)
3136 data->track_data.check_val = check_track_val_max;
3137 else if (handler == HANDLER_ONCHANGE)
3138 data->track_data.check_val = check_track_val_changed;
3139 else {
3140 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3141 ret = -EINVAL;
3142 goto out;
3143 }
3144
3145 data->track_data.save_data = save_track_data_vars;
3146 data->fn = ontrack_action;
3147 data->action = ACTION_SAVE;
3148 } else if (str_has_prefix(action_name, "snapshot")) {
3149 char *params = strsep(&str, ")");
3150
3151 if (!str) {
3152 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params));
3153 ret = -EINVAL;
3154 goto out;
3155 }
3156
3157 if (handler == HANDLER_ONMAX)
3158 data->track_data.check_val = check_track_val_max;
3159 else if (handler == HANDLER_ONCHANGE)
3160 data->track_data.check_val = check_track_val_changed;
3161 else {
3162 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3163 ret = -EINVAL;
3164 goto out;
3165 }
3166
3167 data->track_data.save_data = save_track_data_snapshot;
3168 data->fn = ontrack_action;
3169 data->action = ACTION_SNAPSHOT;
3170 } else {
3171 char *params = strsep(&str, ")");
3172
3173 if (str_has_prefix(action_name, "trace"))
3174 data->use_trace_keyword = true;
3175
3176 if (params) {
3177 ret = parse_action_params(tr, params, data);
3178 if (ret)
3179 goto out;
3180 }
3181
3182 if (handler == HANDLER_ONMAX)
3183 data->track_data.check_val = check_track_val_max;
3184 else if (handler == HANDLER_ONCHANGE)
3185 data->track_data.check_val = check_track_val_changed;
3186
3187 if (handler != HANDLER_ONMATCH) {
3188 data->track_data.save_data = action_trace;
3189 data->fn = ontrack_action;
3190 } else
3191 data->fn = action_trace;
3192
3193 data->action = ACTION_TRACE;
3194 }
3195
3196 data->action_name = kstrdup(action_name, GFP_KERNEL);
3197 if (!data->action_name) {
3198 ret = -ENOMEM;
3199 goto out;
3200 }
3201
3202 data->handler = handler;
3203 out:
3204 return ret;
3205 }
3206
3207 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data,
3208 char *str, enum handler_id handler)
3209 {
3210 struct action_data *data;
3211 int ret = -EINVAL;
3212 char *var_str;
3213
3214 data = kzalloc(sizeof(*data), GFP_KERNEL);
3215 if (!data)
3216 return ERR_PTR(-ENOMEM);
3217
3218 var_str = strsep(&str, ")");
3219 if (!var_str || !str) {
3220 ret = -EINVAL;
3221 goto free;
3222 }
3223
3224 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL);
3225 if (!data->track_data.var_str) {
3226 ret = -ENOMEM;
3227 goto free;
3228 }
3229
3230 ret = action_parse(hist_data->event_file->tr, str, data, handler);
3231 if (ret)
3232 goto free;
3233 out:
3234 return data;
3235 free:
3236 track_data_destroy(hist_data, data);
3237 data = ERR_PTR(ret);
3238 goto out;
3239 }
3240
3241 static void onmatch_destroy(struct action_data *data)
3242 {
3243 kfree(data->match_data.event);
3244 kfree(data->match_data.event_system);
3245
3246 action_data_destroy(data);
3247 }
3248
3249 static void destroy_field_var(struct field_var *field_var)
3250 {
3251 if (!field_var)
3252 return;
3253
3254 destroy_hist_field(field_var->var, 0);
3255 destroy_hist_field(field_var->val, 0);
3256
3257 kfree(field_var);
3258 }
3259
3260 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3261 {
3262 unsigned int i;
3263
3264 for (i = 0; i < hist_data->n_field_vars; i++)
3265 destroy_field_var(hist_data->field_vars[i]);
3266
3267 for (i = 0; i < hist_data->n_save_vars; i++)
3268 destroy_field_var(hist_data->save_vars[i]);
3269 }
3270
3271 static void save_field_var(struct hist_trigger_data *hist_data,
3272 struct field_var *field_var)
3273 {
3274 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3275
3276 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3277 hist_data->n_field_var_str++;
3278 }
3279
3280
3281 static int check_synth_field(struct synth_event *event,
3282 struct hist_field *hist_field,
3283 unsigned int field_pos)
3284 {
3285 struct synth_field *field;
3286
3287 if (field_pos >= event->n_fields)
3288 return -EINVAL;
3289
3290 field = event->fields[field_pos];
3291
3292 /*
3293 * A dynamic string synth field can accept static or
3294 * dynamic. A static string synth field can only accept a
3295 * same-sized static string, which is checked for later.
3296 */
3297 if (strstr(hist_field->type, "char[") && field->is_string
3298 && field->is_dynamic)
3299 return 0;
3300
3301 if (strcmp(field->type, hist_field->type) != 0) {
3302 if (field->size != hist_field->size ||
3303 field->is_signed != hist_field->is_signed)
3304 return -EINVAL;
3305 }
3306
3307 return 0;
3308 }
3309
3310 static struct hist_field *
3311 trace_action_find_var(struct hist_trigger_data *hist_data,
3312 struct action_data *data,
3313 char *system, char *event, char *var)
3314 {
3315 struct trace_array *tr = hist_data->event_file->tr;
3316 struct hist_field *hist_field;
3317
3318 var++; /* skip '$' */
3319
3320 hist_field = find_target_event_var(hist_data, system, event, var);
3321 if (!hist_field) {
3322 if (!system && data->handler == HANDLER_ONMATCH) {
3323 system = data->match_data.event_system;
3324 event = data->match_data.event;
3325 }
3326
3327 hist_field = find_event_var(hist_data, system, event, var);
3328 }
3329
3330 if (!hist_field)
3331 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var));
3332
3333 return hist_field;
3334 }
3335
3336 static struct hist_field *
3337 trace_action_create_field_var(struct hist_trigger_data *hist_data,
3338 struct action_data *data, char *system,
3339 char *event, char *var)
3340 {
3341 struct hist_field *hist_field = NULL;
3342 struct field_var *field_var;
3343
3344 /*
3345 * First try to create a field var on the target event (the
3346 * currently being defined). This will create a variable for
3347 * unqualified fields on the target event, or if qualified,
3348 * target fields that have qualified names matching the target.
3349 */
3350 field_var = create_target_field_var(hist_data, system, event, var);
3351
3352 if (field_var && !IS_ERR(field_var)) {
3353 save_field_var(hist_data, field_var);
3354 hist_field = field_var->var;
3355 } else {
3356 field_var = NULL;
3357 /*
3358 * If no explicit system.event is specified, default to
3359 * looking for fields on the onmatch(system.event.xxx)
3360 * event.
3361 */
3362 if (!system && data->handler == HANDLER_ONMATCH) {
3363 system = data->match_data.event_system;
3364 event = data->match_data.event;
3365 }
3366
3367 /*
3368 * At this point, we're looking at a field on another
3369 * event. Because we can't modify a hist trigger on
3370 * another event to add a variable for a field, we need
3371 * to create a new trigger on that event and create the
3372 * variable at the same time.
3373 */
3374 hist_field = create_field_var_hist(hist_data, system, event, var);
3375 if (IS_ERR(hist_field))
3376 goto free;
3377 }
3378 out:
3379 return hist_field;
3380 free:
3381 destroy_field_var(field_var);
3382 hist_field = NULL;
3383 goto out;
3384 }
3385
3386 static int trace_action_create(struct hist_trigger_data *hist_data,
3387 struct action_data *data)
3388 {
3389 struct trace_array *tr = hist_data->event_file->tr;
3390 char *event_name, *param, *system = NULL;
3391 struct hist_field *hist_field, *var_ref;
3392 unsigned int i;
3393 unsigned int field_pos = 0;
3394 struct synth_event *event;
3395 char *synth_event_name;
3396 int var_ref_idx, ret = 0;
3397
3398 lockdep_assert_held(&event_mutex);
3399
3400 if (data->use_trace_keyword)
3401 synth_event_name = data->synth_event_name;
3402 else
3403 synth_event_name = data->action_name;
3404
3405 event = find_synth_event(synth_event_name);
3406 if (!event) {
3407 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name));
3408 return -EINVAL;
3409 }
3410
3411 event->ref++;
3412
3413 for (i = 0; i < data->n_params; i++) {
3414 char *p;
3415
3416 p = param = kstrdup(data->params[i], GFP_KERNEL);
3417 if (!param) {
3418 ret = -ENOMEM;
3419 goto err;
3420 }
3421
3422 system = strsep(&param, ".");
3423 if (!param) {
3424 param = (char *)system;
3425 system = event_name = NULL;
3426 } else {
3427 event_name = strsep(&param, ".");
3428 if (!param) {
3429 kfree(p);
3430 ret = -EINVAL;
3431 goto err;
3432 }
3433 }
3434
3435 if (param[0] == '$')
3436 hist_field = trace_action_find_var(hist_data, data,
3437 system, event_name,
3438 param);
3439 else
3440 hist_field = trace_action_create_field_var(hist_data,
3441 data,
3442 system,
3443 event_name,
3444 param);
3445
3446 if (!hist_field) {
3447 kfree(p);
3448 ret = -EINVAL;
3449 goto err;
3450 }
3451
3452 if (check_synth_field(event, hist_field, field_pos) == 0) {
3453 var_ref = create_var_ref(hist_data, hist_field,
3454 system, event_name);
3455 if (!var_ref) {
3456 kfree(p);
3457 ret = -ENOMEM;
3458 goto err;
3459 }
3460
3461 var_ref_idx = find_var_ref_idx(hist_data, var_ref);
3462 if (WARN_ON(var_ref_idx < 0)) {
3463 ret = var_ref_idx;
3464 goto err;
3465 }
3466
3467 data->var_ref_idx[i] = var_ref_idx;
3468
3469 field_pos++;
3470 kfree(p);
3471 continue;
3472 }
3473
3474 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param));
3475 kfree(p);
3476 ret = -EINVAL;
3477 goto err;
3478 }
3479
3480 if (field_pos != event->n_fields) {
3481 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name));
3482 ret = -EINVAL;
3483 goto err;
3484 }
3485
3486 data->synth_event = event;
3487 out:
3488 return ret;
3489 err:
3490 event->ref--;
3491
3492 goto out;
3493 }
3494
3495 static int action_create(struct hist_trigger_data *hist_data,
3496 struct action_data *data)
3497 {
3498 struct trace_event_file *file = hist_data->event_file;
3499 struct trace_array *tr = file->tr;
3500 struct track_data *track_data;
3501 struct field_var *field_var;
3502 unsigned int i;
3503 char *param;
3504 int ret = 0;
3505
3506 if (data->action == ACTION_TRACE)
3507 return trace_action_create(hist_data, data);
3508
3509 if (data->action == ACTION_SNAPSHOT) {
3510 track_data = track_data_alloc(hist_data->key_size, data, hist_data);
3511 if (IS_ERR(track_data)) {
3512 ret = PTR_ERR(track_data);
3513 goto out;
3514 }
3515
3516 ret = tracing_snapshot_cond_enable(file->tr, track_data,
3517 cond_snapshot_update);
3518 if (ret)
3519 track_data_free(track_data);
3520
3521 goto out;
3522 }
3523
3524 if (data->action == ACTION_SAVE) {
3525 if (hist_data->n_save_vars) {
3526 ret = -EEXIST;
3527 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0);
3528 goto out;
3529 }
3530
3531 for (i = 0; i < data->n_params; i++) {
3532 param = kstrdup(data->params[i], GFP_KERNEL);
3533 if (!param) {
3534 ret = -ENOMEM;
3535 goto out;
3536 }
3537
3538 field_var = create_target_field_var(hist_data, NULL, NULL, param);
3539 if (IS_ERR(field_var)) {
3540 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL,
3541 errpos(param));
3542 ret = PTR_ERR(field_var);
3543 kfree(param);
3544 goto out;
3545 }
3546
3547 hist_data->save_vars[hist_data->n_save_vars++] = field_var;
3548 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3549 hist_data->n_save_var_str++;
3550 kfree(param);
3551 }
3552 }
3553 out:
3554 return ret;
3555 }
3556
3557 static int onmatch_create(struct hist_trigger_data *hist_data,
3558 struct action_data *data)
3559 {
3560 return action_create(hist_data, data);
3561 }
3562
3563 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
3564 {
3565 char *match_event, *match_event_system;
3566 struct action_data *data;
3567 int ret = -EINVAL;
3568
3569 data = kzalloc(sizeof(*data), GFP_KERNEL);
3570 if (!data)
3571 return ERR_PTR(-ENOMEM);
3572
3573 match_event = strsep(&str, ")");
3574 if (!match_event || !str) {
3575 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event));
3576 goto free;
3577 }
3578
3579 match_event_system = strsep(&match_event, ".");
3580 if (!match_event) {
3581 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system));
3582 goto free;
3583 }
3584
3585 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
3586 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event));
3587 goto free;
3588 }
3589
3590 data->match_data.event = kstrdup(match_event, GFP_KERNEL);
3591 if (!data->match_data.event) {
3592 ret = -ENOMEM;
3593 goto free;
3594 }
3595
3596 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL);
3597 if (!data->match_data.event_system) {
3598 ret = -ENOMEM;
3599 goto free;
3600 }
3601
3602 ret = action_parse(tr, str, data, HANDLER_ONMATCH);
3603 if (ret)
3604 goto free;
3605 out:
3606 return data;
3607 free:
3608 onmatch_destroy(data);
3609 data = ERR_PTR(ret);
3610 goto out;
3611 }
3612
3613 static int create_hitcount_val(struct hist_trigger_data *hist_data)
3614 {
3615 hist_data->fields[HITCOUNT_IDX] =
3616 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
3617 if (!hist_data->fields[HITCOUNT_IDX])
3618 return -ENOMEM;
3619
3620 hist_data->n_vals++;
3621 hist_data->n_fields++;
3622
3623 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
3624 return -EINVAL;
3625
3626 return 0;
3627 }
3628
3629 static int __create_val_field(struct hist_trigger_data *hist_data,
3630 unsigned int val_idx,
3631 struct trace_event_file *file,
3632 char *var_name, char *field_str,
3633 unsigned long flags)
3634 {
3635 struct hist_field *hist_field;
3636 int ret = 0;
3637
3638 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
3639 if (IS_ERR(hist_field)) {
3640 ret = PTR_ERR(hist_field);
3641 goto out;
3642 }
3643
3644 hist_data->fields[val_idx] = hist_field;
3645
3646 ++hist_data->n_vals;
3647 ++hist_data->n_fields;
3648
3649 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3650 ret = -EINVAL;
3651 out:
3652 return ret;
3653 }
3654
3655 static int create_val_field(struct hist_trigger_data *hist_data,
3656 unsigned int val_idx,
3657 struct trace_event_file *file,
3658 char *field_str)
3659 {
3660 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
3661 return -EINVAL;
3662
3663 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
3664 }
3665
3666 static int create_var_field(struct hist_trigger_data *hist_data,
3667 unsigned int val_idx,
3668 struct trace_event_file *file,
3669 char *var_name, char *expr_str)
3670 {
3671 struct trace_array *tr = hist_data->event_file->tr;
3672 unsigned long flags = 0;
3673 int ret;
3674
3675 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3676 return -EINVAL;
3677
3678 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
3679 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name));
3680 return -EINVAL;
3681 }
3682
3683 flags |= HIST_FIELD_FL_VAR;
3684 hist_data->n_vars++;
3685 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
3686 return -EINVAL;
3687
3688 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
3689
3690 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING)
3691 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
3692
3693 return ret;
3694 }
3695
3696 static int create_val_fields(struct hist_trigger_data *hist_data,
3697 struct trace_event_file *file)
3698 {
3699 char *fields_str, *field_str;
3700 unsigned int i, j = 1;
3701 int ret;
3702
3703 ret = create_hitcount_val(hist_data);
3704 if (ret)
3705 goto out;
3706
3707 fields_str = hist_data->attrs->vals_str;
3708 if (!fields_str)
3709 goto out;
3710
3711 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
3712 j < TRACING_MAP_VALS_MAX; i++) {
3713 field_str = strsep(&fields_str, ",");
3714 if (!field_str)
3715 break;
3716
3717 if (strcmp(field_str, "hitcount") == 0)
3718 continue;
3719
3720 ret = create_val_field(hist_data, j++, file, field_str);
3721 if (ret)
3722 goto out;
3723 }
3724
3725 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
3726 ret = -EINVAL;
3727 out:
3728 return ret;
3729 }
3730
3731 static int create_key_field(struct hist_trigger_data *hist_data,
3732 unsigned int key_idx,
3733 unsigned int key_offset,
3734 struct trace_event_file *file,
3735 char *field_str)
3736 {
3737 struct trace_array *tr = hist_data->event_file->tr;
3738 struct hist_field *hist_field = NULL;
3739 unsigned long flags = 0;
3740 unsigned int key_size;
3741 int ret = 0;
3742
3743 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
3744 return -EINVAL;
3745
3746 flags |= HIST_FIELD_FL_KEY;
3747
3748 if (strcmp(field_str, "stacktrace") == 0) {
3749 flags |= HIST_FIELD_FL_STACKTRACE;
3750 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
3751 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
3752 } else {
3753 hist_field = parse_expr(hist_data, file, field_str, flags,
3754 NULL, 0);
3755 if (IS_ERR(hist_field)) {
3756 ret = PTR_ERR(hist_field);
3757 goto out;
3758 }
3759
3760 if (field_has_hist_vars(hist_field, 0)) {
3761 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str));
3762 destroy_hist_field(hist_field, 0);
3763 ret = -EINVAL;
3764 goto out;
3765 }
3766
3767 key_size = hist_field->size;
3768 }
3769
3770 hist_data->fields[key_idx] = hist_field;
3771
3772 key_size = ALIGN(key_size, sizeof(u64));
3773 hist_data->fields[key_idx]->size = key_size;
3774 hist_data->fields[key_idx]->offset = key_offset;
3775
3776 hist_data->key_size += key_size;
3777
3778 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
3779 ret = -EINVAL;
3780 goto out;
3781 }
3782
3783 hist_data->n_keys++;
3784 hist_data->n_fields++;
3785
3786 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
3787 return -EINVAL;
3788
3789 ret = key_size;
3790 out:
3791 return ret;
3792 }
3793
3794 static int create_key_fields(struct hist_trigger_data *hist_data,
3795 struct trace_event_file *file)
3796 {
3797 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
3798 char *fields_str, *field_str;
3799 int ret = -EINVAL;
3800
3801 fields_str = hist_data->attrs->keys_str;
3802 if (!fields_str)
3803 goto out;
3804
3805 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
3806 field_str = strsep(&fields_str, ",");
3807 if (!field_str)
3808 break;
3809 ret = create_key_field(hist_data, i, key_offset,
3810 file, field_str);
3811 if (ret < 0)
3812 goto out;
3813 key_offset += ret;
3814 }
3815 if (fields_str) {
3816 ret = -EINVAL;
3817 goto out;
3818 }
3819 ret = 0;
3820 out:
3821 return ret;
3822 }
3823
3824 static int create_var_fields(struct hist_trigger_data *hist_data,
3825 struct trace_event_file *file)
3826 {
3827 unsigned int i, j = hist_data->n_vals;
3828 int ret = 0;
3829
3830 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
3831
3832 for (i = 0; i < n_vars; i++) {
3833 char *var_name = hist_data->attrs->var_defs.name[i];
3834 char *expr = hist_data->attrs->var_defs.expr[i];
3835
3836 ret = create_var_field(hist_data, j++, file, var_name, expr);
3837 if (ret)
3838 goto out;
3839 }
3840 out:
3841 return ret;
3842 }
3843
3844 static void free_var_defs(struct hist_trigger_data *hist_data)
3845 {
3846 unsigned int i;
3847
3848 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
3849 kfree(hist_data->attrs->var_defs.name[i]);
3850 kfree(hist_data->attrs->var_defs.expr[i]);
3851 }
3852
3853 hist_data->attrs->var_defs.n_vars = 0;
3854 }
3855
3856 static int parse_var_defs(struct hist_trigger_data *hist_data)
3857 {
3858 struct trace_array *tr = hist_data->event_file->tr;
3859 char *s, *str, *var_name, *field_str;
3860 unsigned int i, j, n_vars = 0;
3861 int ret = 0;
3862
3863 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
3864 str = hist_data->attrs->assignment_str[i];
3865 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
3866 field_str = strsep(&str, ",");
3867 if (!field_str)
3868 break;
3869
3870 var_name = strsep(&field_str, "=");
3871 if (!var_name || !field_str) {
3872 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT,
3873 errpos(var_name));
3874 ret = -EINVAL;
3875 goto free;
3876 }
3877
3878 if (n_vars == TRACING_MAP_VARS_MAX) {
3879 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name));
3880 ret = -EINVAL;
3881 goto free;
3882 }
3883
3884 s = kstrdup(var_name, GFP_KERNEL);
3885 if (!s) {
3886 ret = -ENOMEM;
3887 goto free;
3888 }
3889 hist_data->attrs->var_defs.name[n_vars] = s;
3890
3891 s = kstrdup(field_str, GFP_KERNEL);
3892 if (!s) {
3893 ret = -ENOMEM;
3894 goto free;
3895 }
3896 hist_data->attrs->var_defs.expr[n_vars++] = s;
3897
3898 hist_data->attrs->var_defs.n_vars = n_vars;
3899 }
3900 }
3901
3902 return ret;
3903 free:
3904 free_var_defs(hist_data);
3905
3906 return ret;
3907 }
3908
3909 static int create_hist_fields(struct hist_trigger_data *hist_data,
3910 struct trace_event_file *file)
3911 {
3912 int ret;
3913
3914 ret = parse_var_defs(hist_data);
3915 if (ret)
3916 goto out;
3917
3918 ret = create_val_fields(hist_data, file);
3919 if (ret)
3920 goto out;
3921
3922 ret = create_var_fields(hist_data, file);
3923 if (ret)
3924 goto out;
3925
3926 ret = create_key_fields(hist_data, file);
3927 if (ret)
3928 goto out;
3929 out:
3930 free_var_defs(hist_data);
3931
3932 return ret;
3933 }
3934
3935 static int is_descending(struct trace_array *tr, const char *str)
3936 {
3937 if (!str)
3938 return 0;
3939
3940 if (strcmp(str, "descending") == 0)
3941 return 1;
3942
3943 if (strcmp(str, "ascending") == 0)
3944 return 0;
3945
3946 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str));
3947
3948 return -EINVAL;
3949 }
3950
3951 static int create_sort_keys(struct hist_trigger_data *hist_data)
3952 {
3953 struct trace_array *tr = hist_data->event_file->tr;
3954 char *fields_str = hist_data->attrs->sort_key_str;
3955 struct tracing_map_sort_key *sort_key;
3956 int descending, ret = 0;
3957 unsigned int i, j, k;
3958
3959 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
3960
3961 if (!fields_str)
3962 goto out;
3963
3964 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
3965 struct hist_field *hist_field;
3966 char *field_str, *field_name;
3967 const char *test_name;
3968
3969 sort_key = &hist_data->sort_keys[i];
3970
3971 field_str = strsep(&fields_str, ",");
3972 if (!field_str)
3973 break;
3974
3975 if (!*field_str) {
3976 ret = -EINVAL;
3977 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
3978 break;
3979 }
3980
3981 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
3982 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort="));
3983 ret = -EINVAL;
3984 break;
3985 }
3986
3987 field_name = strsep(&field_str, ".");
3988 if (!field_name || !*field_name) {
3989 ret = -EINVAL;
3990 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
3991 break;
3992 }
3993
3994 if (strcmp(field_name, "hitcount") == 0) {
3995 descending = is_descending(tr, field_str);
3996 if (descending < 0) {
3997 ret = descending;
3998 break;
3999 }
4000 sort_key->descending = descending;
4001 continue;
4002 }
4003
4004 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4005 unsigned int idx;
4006
4007 hist_field = hist_data->fields[j];
4008 if (hist_field->flags & HIST_FIELD_FL_VAR)
4009 continue;
4010
4011 idx = k++;
4012
4013 test_name = hist_field_name(hist_field, 0);
4014
4015 if (strcmp(field_name, test_name) == 0) {
4016 sort_key->field_idx = idx;
4017 descending = is_descending(tr, field_str);
4018 if (descending < 0) {
4019 ret = descending;
4020 goto out;
4021 }
4022 sort_key->descending = descending;
4023 break;
4024 }
4025 }
4026 if (j == hist_data->n_fields) {
4027 ret = -EINVAL;
4028 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name));
4029 break;
4030 }
4031 }
4032
4033 hist_data->n_sort_keys = i;
4034 out:
4035 return ret;
4036 }
4037
4038 static void destroy_actions(struct hist_trigger_data *hist_data)
4039 {
4040 unsigned int i;
4041
4042 for (i = 0; i < hist_data->n_actions; i++) {
4043 struct action_data *data = hist_data->actions[i];
4044
4045 if (data->handler == HANDLER_ONMATCH)
4046 onmatch_destroy(data);
4047 else if (data->handler == HANDLER_ONMAX ||
4048 data->handler == HANDLER_ONCHANGE)
4049 track_data_destroy(hist_data, data);
4050 else
4051 kfree(data);
4052 }
4053 }
4054
4055 static int parse_actions(struct hist_trigger_data *hist_data)
4056 {
4057 struct trace_array *tr = hist_data->event_file->tr;
4058 struct action_data *data;
4059 unsigned int i;
4060 int ret = 0;
4061 char *str;
4062 int len;
4063
4064 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4065 str = hist_data->attrs->action_str[i];
4066
4067 if ((len = str_has_prefix(str, "onmatch("))) {
4068 char *action_str = str + len;
4069
4070 data = onmatch_parse(tr, action_str);
4071 if (IS_ERR(data)) {
4072 ret = PTR_ERR(data);
4073 break;
4074 }
4075 } else if ((len = str_has_prefix(str, "onmax("))) {
4076 char *action_str = str + len;
4077
4078 data = track_data_parse(hist_data, action_str,
4079 HANDLER_ONMAX);
4080 if (IS_ERR(data)) {
4081 ret = PTR_ERR(data);
4082 break;
4083 }
4084 } else if ((len = str_has_prefix(str, "onchange("))) {
4085 char *action_str = str + len;
4086
4087 data = track_data_parse(hist_data, action_str,
4088 HANDLER_ONCHANGE);
4089 if (IS_ERR(data)) {
4090 ret = PTR_ERR(data);
4091 break;
4092 }
4093 } else {
4094 ret = -EINVAL;
4095 break;
4096 }
4097
4098 hist_data->actions[hist_data->n_actions++] = data;
4099 }
4100
4101 return ret;
4102 }
4103
4104 static int create_actions(struct hist_trigger_data *hist_data)
4105 {
4106 struct action_data *data;
4107 unsigned int i;
4108 int ret = 0;
4109
4110 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4111 data = hist_data->actions[i];
4112
4113 if (data->handler == HANDLER_ONMATCH) {
4114 ret = onmatch_create(hist_data, data);
4115 if (ret)
4116 break;
4117 } else if (data->handler == HANDLER_ONMAX ||
4118 data->handler == HANDLER_ONCHANGE) {
4119 ret = track_data_create(hist_data, data);
4120 if (ret)
4121 break;
4122 } else {
4123 ret = -EINVAL;
4124 break;
4125 }
4126 }
4127
4128 return ret;
4129 }
4130
4131 static void print_actions(struct seq_file *m,
4132 struct hist_trigger_data *hist_data,
4133 struct tracing_map_elt *elt)
4134 {
4135 unsigned int i;
4136
4137 for (i = 0; i < hist_data->n_actions; i++) {
4138 struct action_data *data = hist_data->actions[i];
4139
4140 if (data->action == ACTION_SNAPSHOT)
4141 continue;
4142
4143 if (data->handler == HANDLER_ONMAX ||
4144 data->handler == HANDLER_ONCHANGE)
4145 track_data_print(m, hist_data, elt, data);
4146 }
4147 }
4148
4149 static void print_action_spec(struct seq_file *m,
4150 struct hist_trigger_data *hist_data,
4151 struct action_data *data)
4152 {
4153 unsigned int i;
4154
4155 if (data->action == ACTION_SAVE) {
4156 for (i = 0; i < hist_data->n_save_vars; i++) {
4157 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name);
4158 if (i < hist_data->n_save_vars - 1)
4159 seq_puts(m, ",");
4160 }
4161 } else if (data->action == ACTION_TRACE) {
4162 if (data->use_trace_keyword)
4163 seq_printf(m, "%s", data->synth_event_name);
4164 for (i = 0; i < data->n_params; i++) {
4165 if (i || data->use_trace_keyword)
4166 seq_puts(m, ",");
4167 seq_printf(m, "%s", data->params[i]);
4168 }
4169 }
4170 }
4171
4172 static void print_track_data_spec(struct seq_file *m,
4173 struct hist_trigger_data *hist_data,
4174 struct action_data *data)
4175 {
4176 if (data->handler == HANDLER_ONMAX)
4177 seq_puts(m, ":onmax(");
4178 else if (data->handler == HANDLER_ONCHANGE)
4179 seq_puts(m, ":onchange(");
4180 seq_printf(m, "%s", data->track_data.var_str);
4181 seq_printf(m, ").%s(", data->action_name);
4182
4183 print_action_spec(m, hist_data, data);
4184
4185 seq_puts(m, ")");
4186 }
4187
4188 static void print_onmatch_spec(struct seq_file *m,
4189 struct hist_trigger_data *hist_data,
4190 struct action_data *data)
4191 {
4192 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system,
4193 data->match_data.event);
4194
4195 seq_printf(m, "%s(", data->action_name);
4196
4197 print_action_spec(m, hist_data, data);
4198
4199 seq_puts(m, ")");
4200 }
4201
4202 static bool actions_match(struct hist_trigger_data *hist_data,
4203 struct hist_trigger_data *hist_data_test)
4204 {
4205 unsigned int i, j;
4206
4207 if (hist_data->n_actions != hist_data_test->n_actions)
4208 return false;
4209
4210 for (i = 0; i < hist_data->n_actions; i++) {
4211 struct action_data *data = hist_data->actions[i];
4212 struct action_data *data_test = hist_data_test->actions[i];
4213 char *action_name, *action_name_test;
4214
4215 if (data->handler != data_test->handler)
4216 return false;
4217 if (data->action != data_test->action)
4218 return false;
4219
4220 if (data->n_params != data_test->n_params)
4221 return false;
4222
4223 for (j = 0; j < data->n_params; j++) {
4224 if (strcmp(data->params[j], data_test->params[j]) != 0)
4225 return false;
4226 }
4227
4228 if (data->use_trace_keyword)
4229 action_name = data->synth_event_name;
4230 else
4231 action_name = data->action_name;
4232
4233 if (data_test->use_trace_keyword)
4234 action_name_test = data_test->synth_event_name;
4235 else
4236 action_name_test = data_test->action_name;
4237
4238 if (strcmp(action_name, action_name_test) != 0)
4239 return false;
4240
4241 if (data->handler == HANDLER_ONMATCH) {
4242 if (strcmp(data->match_data.event_system,
4243 data_test->match_data.event_system) != 0)
4244 return false;
4245 if (strcmp(data->match_data.event,
4246 data_test->match_data.event) != 0)
4247 return false;
4248 } else if (data->handler == HANDLER_ONMAX ||
4249 data->handler == HANDLER_ONCHANGE) {
4250 if (strcmp(data->track_data.var_str,
4251 data_test->track_data.var_str) != 0)
4252 return false;
4253 }
4254 }
4255
4256 return true;
4257 }
4258
4259
4260 static void print_actions_spec(struct seq_file *m,
4261 struct hist_trigger_data *hist_data)
4262 {
4263 unsigned int i;
4264
4265 for (i = 0; i < hist_data->n_actions; i++) {
4266 struct action_data *data = hist_data->actions[i];
4267
4268 if (data->handler == HANDLER_ONMATCH)
4269 print_onmatch_spec(m, hist_data, data);
4270 else if (data->handler == HANDLER_ONMAX ||
4271 data->handler == HANDLER_ONCHANGE)
4272 print_track_data_spec(m, hist_data, data);
4273 }
4274 }
4275
4276 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4277 {
4278 unsigned int i;
4279
4280 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4281 kfree(hist_data->field_var_hists[i]->cmd);
4282 kfree(hist_data->field_var_hists[i]);
4283 }
4284 }
4285
4286 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4287 {
4288 if (!hist_data)
4289 return;
4290
4291 destroy_hist_trigger_attrs(hist_data->attrs);
4292 destroy_hist_fields(hist_data);
4293 tracing_map_destroy(hist_data->map);
4294
4295 destroy_actions(hist_data);
4296 destroy_field_vars(hist_data);
4297 destroy_field_var_hists(hist_data);
4298
4299 kfree(hist_data);
4300 }
4301
4302 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4303 {
4304 struct tracing_map *map = hist_data->map;
4305 struct ftrace_event_field *field;
4306 struct hist_field *hist_field;
4307 int i, idx = 0;
4308
4309 for_each_hist_field(i, hist_data) {
4310 hist_field = hist_data->fields[i];
4311 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4312 tracing_map_cmp_fn_t cmp_fn;
4313
4314 field = hist_field->field;
4315
4316 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4317 cmp_fn = tracing_map_cmp_none;
4318 else if (!field)
4319 cmp_fn = tracing_map_cmp_num(hist_field->size,
4320 hist_field->is_signed);
4321 else if (is_string_field(field))
4322 cmp_fn = tracing_map_cmp_string;
4323 else
4324 cmp_fn = tracing_map_cmp_num(field->size,
4325 field->is_signed);
4326 idx = tracing_map_add_key_field(map,
4327 hist_field->offset,
4328 cmp_fn);
4329 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4330 idx = tracing_map_add_sum_field(map);
4331
4332 if (idx < 0)
4333 return idx;
4334
4335 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4336 idx = tracing_map_add_var(map);
4337 if (idx < 0)
4338 return idx;
4339 hist_field->var.idx = idx;
4340 hist_field->var.hist_data = hist_data;
4341 }
4342 }
4343
4344 return 0;
4345 }
4346
4347 static struct hist_trigger_data *
4348 create_hist_data(unsigned int map_bits,
4349 struct hist_trigger_attrs *attrs,
4350 struct trace_event_file *file,
4351 bool remove)
4352 {
4353 const struct tracing_map_ops *map_ops = NULL;
4354 struct hist_trigger_data *hist_data;
4355 int ret = 0;
4356
4357 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4358 if (!hist_data)
4359 return ERR_PTR(-ENOMEM);
4360
4361 hist_data->attrs = attrs;
4362 hist_data->remove = remove;
4363 hist_data->event_file = file;
4364
4365 ret = parse_actions(hist_data);
4366 if (ret)
4367 goto free;
4368
4369 ret = create_hist_fields(hist_data, file);
4370 if (ret)
4371 goto free;
4372
4373 ret = create_sort_keys(hist_data);
4374 if (ret)
4375 goto free;
4376
4377 map_ops = &hist_trigger_elt_data_ops;
4378
4379 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
4380 map_ops, hist_data);
4381 if (IS_ERR(hist_data->map)) {
4382 ret = PTR_ERR(hist_data->map);
4383 hist_data->map = NULL;
4384 goto free;
4385 }
4386
4387 ret = create_tracing_map_fields(hist_data);
4388 if (ret)
4389 goto free;
4390 out:
4391 return hist_data;
4392 free:
4393 hist_data->attrs = NULL;
4394
4395 destroy_hist_data(hist_data);
4396
4397 hist_data = ERR_PTR(ret);
4398
4399 goto out;
4400 }
4401
4402 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
4403 struct tracing_map_elt *elt, void *rec,
4404 struct ring_buffer_event *rbe,
4405 u64 *var_ref_vals)
4406 {
4407 struct hist_elt_data *elt_data;
4408 struct hist_field *hist_field;
4409 unsigned int i, var_idx;
4410 u64 hist_val;
4411
4412 elt_data = elt->private_data;
4413 elt_data->var_ref_vals = var_ref_vals;
4414
4415 for_each_hist_val_field(i, hist_data) {
4416 hist_field = hist_data->fields[i];
4417 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4418 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4419 var_idx = hist_field->var.idx;
4420
4421 if (hist_field->flags & HIST_FIELD_FL_STRING) {
4422 unsigned int str_start, var_str_idx, idx;
4423 char *str, *val_str;
4424
4425 str_start = hist_data->n_field_var_str +
4426 hist_data->n_save_var_str;
4427 var_str_idx = hist_field->var_str_idx;
4428 idx = str_start + var_str_idx;
4429
4430 str = elt_data->field_var_str[idx];
4431 val_str = (char *)(uintptr_t)hist_val;
4432 strscpy(str, val_str, STR_VAR_LEN_MAX);
4433
4434 hist_val = (u64)(uintptr_t)str;
4435 }
4436 tracing_map_set_var(elt, var_idx, hist_val);
4437 continue;
4438 }
4439 tracing_map_update_sum(elt, i, hist_val);
4440 }
4441
4442 for_each_hist_key_field(i, hist_data) {
4443 hist_field = hist_data->fields[i];
4444 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4445 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4446 var_idx = hist_field->var.idx;
4447 tracing_map_set_var(elt, var_idx, hist_val);
4448 }
4449 }
4450
4451 update_field_vars(hist_data, elt, rbe, rec);
4452 }
4453
4454 static inline void add_to_key(char *compound_key, void *key,
4455 struct hist_field *key_field, void *rec)
4456 {
4457 size_t size = key_field->size;
4458
4459 if (key_field->flags & HIST_FIELD_FL_STRING) {
4460 struct ftrace_event_field *field;
4461
4462 field = key_field->field;
4463 if (field->filter_type == FILTER_DYN_STRING)
4464 size = *(u32 *)(rec + field->offset) >> 16;
4465 else if (field->filter_type == FILTER_PTR_STRING)
4466 size = strlen(key);
4467 else if (field->filter_type == FILTER_STATIC_STRING)
4468 size = field->size;
4469
4470 /* ensure NULL-termination */
4471 if (size > key_field->size - 1)
4472 size = key_field->size - 1;
4473
4474 strncpy(compound_key + key_field->offset, (char *)key, size);
4475 } else
4476 memcpy(compound_key + key_field->offset, key, size);
4477 }
4478
4479 static void
4480 hist_trigger_actions(struct hist_trigger_data *hist_data,
4481 struct tracing_map_elt *elt, void *rec,
4482 struct ring_buffer_event *rbe, void *key,
4483 u64 *var_ref_vals)
4484 {
4485 struct action_data *data;
4486 unsigned int i;
4487
4488 for (i = 0; i < hist_data->n_actions; i++) {
4489 data = hist_data->actions[i];
4490 data->fn(hist_data, elt, rec, rbe, key, data, var_ref_vals);
4491 }
4492 }
4493
4494 static void event_hist_trigger(struct event_trigger_data *data, void *rec,
4495 struct ring_buffer_event *rbe)
4496 {
4497 struct hist_trigger_data *hist_data = data->private_data;
4498 bool use_compound_key = (hist_data->n_keys > 1);
4499 unsigned long entries[HIST_STACKTRACE_DEPTH];
4500 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
4501 char compound_key[HIST_KEY_SIZE_MAX];
4502 struct tracing_map_elt *elt = NULL;
4503 struct hist_field *key_field;
4504 u64 field_contents;
4505 void *key = NULL;
4506 unsigned int i;
4507
4508 memset(compound_key, 0, hist_data->key_size);
4509
4510 for_each_hist_key_field(i, hist_data) {
4511 key_field = hist_data->fields[i];
4512
4513 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4514 memset(entries, 0, HIST_STACKTRACE_SIZE);
4515 stack_trace_save(entries, HIST_STACKTRACE_DEPTH,
4516 HIST_STACKTRACE_SKIP);
4517 key = entries;
4518 } else {
4519 field_contents = key_field->fn(key_field, elt, rbe, rec);
4520 if (key_field->flags & HIST_FIELD_FL_STRING) {
4521 key = (void *)(unsigned long)field_contents;
4522 use_compound_key = true;
4523 } else
4524 key = (void *)&field_contents;
4525 }
4526
4527 if (use_compound_key)
4528 add_to_key(compound_key, key, key_field, rec);
4529 }
4530
4531 if (use_compound_key)
4532 key = compound_key;
4533
4534 if (hist_data->n_var_refs &&
4535 !resolve_var_refs(hist_data, key, var_ref_vals, false))
4536 return;
4537
4538 elt = tracing_map_insert(hist_data->map, key);
4539 if (!elt)
4540 return;
4541
4542 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
4543
4544 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
4545 hist_trigger_actions(hist_data, elt, rec, rbe, key, var_ref_vals);
4546 }
4547
4548 static void hist_trigger_stacktrace_print(struct seq_file *m,
4549 unsigned long *stacktrace_entries,
4550 unsigned int max_entries)
4551 {
4552 char str[KSYM_SYMBOL_LEN];
4553 unsigned int spaces = 8;
4554 unsigned int i;
4555
4556 for (i = 0; i < max_entries; i++) {
4557 if (!stacktrace_entries[i])
4558 return;
4559
4560 seq_printf(m, "%*c", 1 + spaces, ' ');
4561 sprint_symbol(str, stacktrace_entries[i]);
4562 seq_printf(m, "%s\n", str);
4563 }
4564 }
4565
4566 static void hist_trigger_print_key(struct seq_file *m,
4567 struct hist_trigger_data *hist_data,
4568 void *key,
4569 struct tracing_map_elt *elt)
4570 {
4571 struct hist_field *key_field;
4572 char str[KSYM_SYMBOL_LEN];
4573 bool multiline = false;
4574 const char *field_name;
4575 unsigned int i;
4576 u64 uval;
4577
4578 seq_puts(m, "{ ");
4579
4580 for_each_hist_key_field(i, hist_data) {
4581 key_field = hist_data->fields[i];
4582
4583 if (i > hist_data->n_vals)
4584 seq_puts(m, ", ");
4585
4586 field_name = hist_field_name(key_field, 0);
4587
4588 if (key_field->flags & HIST_FIELD_FL_HEX) {
4589 uval = *(u64 *)(key + key_field->offset);
4590 seq_printf(m, "%s: %llx", field_name, uval);
4591 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
4592 uval = *(u64 *)(key + key_field->offset);
4593 sprint_symbol_no_offset(str, uval);
4594 seq_printf(m, "%s: [%llx] %-45s", field_name,
4595 uval, str);
4596 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
4597 uval = *(u64 *)(key + key_field->offset);
4598 sprint_symbol(str, uval);
4599 seq_printf(m, "%s: [%llx] %-55s", field_name,
4600 uval, str);
4601 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
4602 struct hist_elt_data *elt_data = elt->private_data;
4603 char *comm;
4604
4605 if (WARN_ON_ONCE(!elt_data))
4606 return;
4607
4608 comm = elt_data->comm;
4609
4610 uval = *(u64 *)(key + key_field->offset);
4611 seq_printf(m, "%s: %-16s[%10llu]", field_name,
4612 comm, uval);
4613 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
4614 const char *syscall_name;
4615
4616 uval = *(u64 *)(key + key_field->offset);
4617 syscall_name = get_syscall_name(uval);
4618 if (!syscall_name)
4619 syscall_name = "unknown_syscall";
4620
4621 seq_printf(m, "%s: %-30s[%3llu]", field_name,
4622 syscall_name, uval);
4623 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4624 seq_puts(m, "stacktrace:\n");
4625 hist_trigger_stacktrace_print(m,
4626 key + key_field->offset,
4627 HIST_STACKTRACE_DEPTH);
4628 multiline = true;
4629 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
4630 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
4631 *(u64 *)(key + key_field->offset));
4632 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
4633 seq_printf(m, "%s: %-50s", field_name,
4634 (char *)(key + key_field->offset));
4635 } else {
4636 uval = *(u64 *)(key + key_field->offset);
4637 seq_printf(m, "%s: %10llu", field_name, uval);
4638 }
4639 }
4640
4641 if (!multiline)
4642 seq_puts(m, " ");
4643
4644 seq_puts(m, "}");
4645 }
4646
4647 static void hist_trigger_entry_print(struct seq_file *m,
4648 struct hist_trigger_data *hist_data,
4649 void *key,
4650 struct tracing_map_elt *elt)
4651 {
4652 const char *field_name;
4653 unsigned int i;
4654
4655 hist_trigger_print_key(m, hist_data, key, elt);
4656
4657 seq_printf(m, " hitcount: %10llu",
4658 tracing_map_read_sum(elt, HITCOUNT_IDX));
4659
4660 for (i = 1; i < hist_data->n_vals; i++) {
4661 field_name = hist_field_name(hist_data->fields[i], 0);
4662
4663 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
4664 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
4665 continue;
4666
4667 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
4668 seq_printf(m, " %s: %10llx", field_name,
4669 tracing_map_read_sum(elt, i));
4670 } else {
4671 seq_printf(m, " %s: %10llu", field_name,
4672 tracing_map_read_sum(elt, i));
4673 }
4674 }
4675
4676 print_actions(m, hist_data, elt);
4677
4678 seq_puts(m, "\n");
4679 }
4680
4681 static int print_entries(struct seq_file *m,
4682 struct hist_trigger_data *hist_data)
4683 {
4684 struct tracing_map_sort_entry **sort_entries = NULL;
4685 struct tracing_map *map = hist_data->map;
4686 int i, n_entries;
4687
4688 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
4689 hist_data->n_sort_keys,
4690 &sort_entries);
4691 if (n_entries < 0)
4692 return n_entries;
4693
4694 for (i = 0; i < n_entries; i++)
4695 hist_trigger_entry_print(m, hist_data,
4696 sort_entries[i]->key,
4697 sort_entries[i]->elt);
4698
4699 tracing_map_destroy_sort_entries(sort_entries, n_entries);
4700
4701 return n_entries;
4702 }
4703
4704 static void hist_trigger_show(struct seq_file *m,
4705 struct event_trigger_data *data, int n)
4706 {
4707 struct hist_trigger_data *hist_data;
4708 int n_entries;
4709
4710 if (n > 0)
4711 seq_puts(m, "\n\n");
4712
4713 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4714 data->ops->print(m, data->ops, data);
4715 seq_puts(m, "#\n\n");
4716
4717 hist_data = data->private_data;
4718 n_entries = print_entries(m, hist_data);
4719 if (n_entries < 0)
4720 n_entries = 0;
4721
4722 track_data_snapshot_print(m, hist_data);
4723
4724 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
4725 (u64)atomic64_read(&hist_data->map->hits),
4726 n_entries, (u64)atomic64_read(&hist_data->map->drops));
4727 }
4728
4729 static int hist_show(struct seq_file *m, void *v)
4730 {
4731 struct event_trigger_data *data;
4732 struct trace_event_file *event_file;
4733 int n = 0, ret = 0;
4734
4735 mutex_lock(&event_mutex);
4736
4737 event_file = event_file_data(m->private);
4738 if (unlikely(!event_file)) {
4739 ret = -ENODEV;
4740 goto out_unlock;
4741 }
4742
4743 list_for_each_entry(data, &event_file->triggers, list) {
4744 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
4745 hist_trigger_show(m, data, n++);
4746 }
4747
4748 out_unlock:
4749 mutex_unlock(&event_mutex);
4750
4751 return ret;
4752 }
4753
4754 static int event_hist_open(struct inode *inode, struct file *file)
4755 {
4756 int ret;
4757
4758 ret = security_locked_down(LOCKDOWN_TRACEFS);
4759 if (ret)
4760 return ret;
4761
4762 return single_open(file, hist_show, file);
4763 }
4764
4765 const struct file_operations event_hist_fops = {
4766 .open = event_hist_open,
4767 .read = seq_read,
4768 .llseek = seq_lseek,
4769 .release = single_release,
4770 };
4771
4772 #ifdef CONFIG_HIST_TRIGGERS_DEBUG
4773 static void hist_field_debug_show_flags(struct seq_file *m,
4774 unsigned long flags)
4775 {
4776 seq_puts(m, " flags:\n");
4777
4778 if (flags & HIST_FIELD_FL_KEY)
4779 seq_puts(m, " HIST_FIELD_FL_KEY\n");
4780 else if (flags & HIST_FIELD_FL_HITCOUNT)
4781 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n");
4782 else if (flags & HIST_FIELD_FL_VAR)
4783 seq_puts(m, " HIST_FIELD_FL_VAR\n");
4784 else if (flags & HIST_FIELD_FL_VAR_REF)
4785 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n");
4786 else
4787 seq_puts(m, " VAL: normal u64 value\n");
4788
4789 if (flags & HIST_FIELD_FL_ALIAS)
4790 seq_puts(m, " HIST_FIELD_FL_ALIAS\n");
4791 }
4792
4793 static int hist_field_debug_show(struct seq_file *m,
4794 struct hist_field *field, unsigned long flags)
4795 {
4796 if ((field->flags & flags) != flags) {
4797 seq_printf(m, "ERROR: bad flags - %lx\n", flags);
4798 return -EINVAL;
4799 }
4800
4801 hist_field_debug_show_flags(m, field->flags);
4802 if (field->field)
4803 seq_printf(m, " ftrace_event_field name: %s\n",
4804 field->field->name);
4805
4806 if (field->flags & HIST_FIELD_FL_VAR) {
4807 seq_printf(m, " var.name: %s\n", field->var.name);
4808 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4809 field->var.idx);
4810 }
4811
4812 if (field->flags & HIST_FIELD_FL_ALIAS)
4813 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
4814 field->var_ref_idx);
4815
4816 if (field->flags & HIST_FIELD_FL_VAR_REF) {
4817 seq_printf(m, " name: %s\n", field->name);
4818 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4819 field->var.idx);
4820 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data);
4821 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
4822 field->var_ref_idx);
4823 if (field->system)
4824 seq_printf(m, " system: %s\n", field->system);
4825 if (field->event_name)
4826 seq_printf(m, " event_name: %s\n", field->event_name);
4827 }
4828
4829 seq_printf(m, " type: %s\n", field->type);
4830 seq_printf(m, " size: %u\n", field->size);
4831 seq_printf(m, " is_signed: %u\n", field->is_signed);
4832
4833 return 0;
4834 }
4835
4836 static int field_var_debug_show(struct seq_file *m,
4837 struct field_var *field_var, unsigned int i,
4838 bool save_vars)
4839 {
4840 const char *vars_name = save_vars ? "save_vars" : "field_vars";
4841 struct hist_field *field;
4842 int ret = 0;
4843
4844 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i);
4845
4846 field = field_var->var;
4847
4848 seq_printf(m, "\n %s[%d].var:\n", vars_name, i);
4849
4850 hist_field_debug_show_flags(m, field->flags);
4851 seq_printf(m, " var.name: %s\n", field->var.name);
4852 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4853 field->var.idx);
4854
4855 field = field_var->val;
4856
4857 seq_printf(m, "\n %s[%d].val:\n", vars_name, i);
4858 if (field->field)
4859 seq_printf(m, " ftrace_event_field name: %s\n",
4860 field->field->name);
4861 else {
4862 ret = -EINVAL;
4863 goto out;
4864 }
4865
4866 seq_printf(m, " type: %s\n", field->type);
4867 seq_printf(m, " size: %u\n", field->size);
4868 seq_printf(m, " is_signed: %u\n", field->is_signed);
4869 out:
4870 return ret;
4871 }
4872
4873 static int hist_action_debug_show(struct seq_file *m,
4874 struct action_data *data, int i)
4875 {
4876 int ret = 0;
4877
4878 if (data->handler == HANDLER_ONMAX ||
4879 data->handler == HANDLER_ONCHANGE) {
4880 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i);
4881 ret = hist_field_debug_show(m, data->track_data.var_ref,
4882 HIST_FIELD_FL_VAR_REF);
4883 if (ret)
4884 goto out;
4885
4886 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i);
4887 ret = hist_field_debug_show(m, data->track_data.track_var,
4888 HIST_FIELD_FL_VAR);
4889 if (ret)
4890 goto out;
4891 }
4892
4893 if (data->handler == HANDLER_ONMATCH) {
4894 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n",
4895 i, data->match_data.event_system);
4896 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n",
4897 i, data->match_data.event);
4898 }
4899 out:
4900 return ret;
4901 }
4902
4903 static int hist_actions_debug_show(struct seq_file *m,
4904 struct hist_trigger_data *hist_data)
4905 {
4906 int i, ret = 0;
4907
4908 if (hist_data->n_actions)
4909 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n");
4910
4911 for (i = 0; i < hist_data->n_actions; i++) {
4912 struct action_data *action = hist_data->actions[i];
4913
4914 ret = hist_action_debug_show(m, action, i);
4915 if (ret)
4916 goto out;
4917 }
4918
4919 if (hist_data->n_save_vars)
4920 seq_puts(m, "\n save action variables (save() params):\n");
4921
4922 for (i = 0; i < hist_data->n_save_vars; i++) {
4923 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true);
4924 if (ret)
4925 goto out;
4926 }
4927 out:
4928 return ret;
4929 }
4930
4931 static void hist_trigger_debug_show(struct seq_file *m,
4932 struct event_trigger_data *data, int n)
4933 {
4934 struct hist_trigger_data *hist_data;
4935 int i, ret;
4936
4937 if (n > 0)
4938 seq_puts(m, "\n\n");
4939
4940 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4941 data->ops->print(m, data->ops, data);
4942 seq_puts(m, "#\n\n");
4943
4944 hist_data = data->private_data;
4945
4946 seq_printf(m, "hist_data: %p\n\n", hist_data);
4947 seq_printf(m, " n_vals: %u\n", hist_data->n_vals);
4948 seq_printf(m, " n_keys: %u\n", hist_data->n_keys);
4949 seq_printf(m, " n_fields: %u\n", hist_data->n_fields);
4950
4951 seq_puts(m, "\n val fields:\n\n");
4952
4953 seq_puts(m, " hist_data->fields[0]:\n");
4954 ret = hist_field_debug_show(m, hist_data->fields[0],
4955 HIST_FIELD_FL_HITCOUNT);
4956 if (ret)
4957 return;
4958
4959 for (i = 1; i < hist_data->n_vals; i++) {
4960 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
4961 ret = hist_field_debug_show(m, hist_data->fields[i], 0);
4962 if (ret)
4963 return;
4964 }
4965
4966 seq_puts(m, "\n key fields:\n");
4967
4968 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) {
4969 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
4970 ret = hist_field_debug_show(m, hist_data->fields[i],
4971 HIST_FIELD_FL_KEY);
4972 if (ret)
4973 return;
4974 }
4975
4976 if (hist_data->n_var_refs)
4977 seq_puts(m, "\n variable reference fields:\n");
4978
4979 for (i = 0; i < hist_data->n_var_refs; i++) {
4980 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i);
4981 ret = hist_field_debug_show(m, hist_data->var_refs[i],
4982 HIST_FIELD_FL_VAR_REF);
4983 if (ret)
4984 return;
4985 }
4986
4987 if (hist_data->n_field_vars)
4988 seq_puts(m, "\n field variables:\n");
4989
4990 for (i = 0; i < hist_data->n_field_vars; i++) {
4991 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false);
4992 if (ret)
4993 return;
4994 }
4995
4996 ret = hist_actions_debug_show(m, hist_data);
4997 if (ret)
4998 return;
4999 }
5000
5001 static int hist_debug_show(struct seq_file *m, void *v)
5002 {
5003 struct event_trigger_data *data;
5004 struct trace_event_file *event_file;
5005 int n = 0, ret = 0;
5006
5007 mutex_lock(&event_mutex);
5008
5009 event_file = event_file_data(m->private);
5010 if (unlikely(!event_file)) {
5011 ret = -ENODEV;
5012 goto out_unlock;
5013 }
5014
5015 list_for_each_entry(data, &event_file->triggers, list) {
5016 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5017 hist_trigger_debug_show(m, data, n++);
5018 }
5019
5020 out_unlock:
5021 mutex_unlock(&event_mutex);
5022
5023 return ret;
5024 }
5025
5026 static int event_hist_debug_open(struct inode *inode, struct file *file)
5027 {
5028 int ret;
5029
5030 ret = security_locked_down(LOCKDOWN_TRACEFS);
5031 if (ret)
5032 return ret;
5033
5034 return single_open(file, hist_debug_show, file);
5035 }
5036
5037 const struct file_operations event_hist_debug_fops = {
5038 .open = event_hist_debug_open,
5039 .read = seq_read,
5040 .llseek = seq_lseek,
5041 .release = single_release,
5042 };
5043 #endif
5044
5045 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
5046 {
5047 const char *field_name = hist_field_name(hist_field, 0);
5048
5049 if (hist_field->var.name)
5050 seq_printf(m, "%s=", hist_field->var.name);
5051
5052 if (hist_field->flags & HIST_FIELD_FL_CPU)
5053 seq_puts(m, "cpu");
5054 else if (field_name) {
5055 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
5056 hist_field->flags & HIST_FIELD_FL_ALIAS)
5057 seq_putc(m, '$');
5058 seq_printf(m, "%s", field_name);
5059 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
5060 seq_puts(m, "common_timestamp");
5061
5062 if (hist_field->flags) {
5063 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
5064 !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
5065 const char *flags = get_hist_field_flags(hist_field);
5066
5067 if (flags)
5068 seq_printf(m, ".%s", flags);
5069 }
5070 }
5071 }
5072
5073 static int event_hist_trigger_print(struct seq_file *m,
5074 struct event_trigger_ops *ops,
5075 struct event_trigger_data *data)
5076 {
5077 struct hist_trigger_data *hist_data = data->private_data;
5078 struct hist_field *field;
5079 bool have_var = false;
5080 unsigned int i;
5081
5082 seq_puts(m, "hist:");
5083
5084 if (data->name)
5085 seq_printf(m, "%s:", data->name);
5086
5087 seq_puts(m, "keys=");
5088
5089 for_each_hist_key_field(i, hist_data) {
5090 field = hist_data->fields[i];
5091
5092 if (i > hist_data->n_vals)
5093 seq_puts(m, ",");
5094
5095 if (field->flags & HIST_FIELD_FL_STACKTRACE)
5096 seq_puts(m, "stacktrace");
5097 else
5098 hist_field_print(m, field);
5099 }
5100
5101 seq_puts(m, ":vals=");
5102
5103 for_each_hist_val_field(i, hist_data) {
5104 field = hist_data->fields[i];
5105 if (field->flags & HIST_FIELD_FL_VAR) {
5106 have_var = true;
5107 continue;
5108 }
5109
5110 if (i == HITCOUNT_IDX)
5111 seq_puts(m, "hitcount");
5112 else {
5113 seq_puts(m, ",");
5114 hist_field_print(m, field);
5115 }
5116 }
5117
5118 if (have_var) {
5119 unsigned int n = 0;
5120
5121 seq_puts(m, ":");
5122
5123 for_each_hist_val_field(i, hist_data) {
5124 field = hist_data->fields[i];
5125
5126 if (field->flags & HIST_FIELD_FL_VAR) {
5127 if (n++)
5128 seq_puts(m, ",");
5129 hist_field_print(m, field);
5130 }
5131 }
5132 }
5133
5134 seq_puts(m, ":sort=");
5135
5136 for (i = 0; i < hist_data->n_sort_keys; i++) {
5137 struct tracing_map_sort_key *sort_key;
5138 unsigned int idx, first_key_idx;
5139
5140 /* skip VAR vals */
5141 first_key_idx = hist_data->n_vals - hist_data->n_vars;
5142
5143 sort_key = &hist_data->sort_keys[i];
5144 idx = sort_key->field_idx;
5145
5146 if (WARN_ON(idx >= HIST_FIELDS_MAX))
5147 return -EINVAL;
5148
5149 if (i > 0)
5150 seq_puts(m, ",");
5151
5152 if (idx == HITCOUNT_IDX)
5153 seq_puts(m, "hitcount");
5154 else {
5155 if (idx >= first_key_idx)
5156 idx += hist_data->n_vars;
5157 hist_field_print(m, hist_data->fields[idx]);
5158 }
5159
5160 if (sort_key->descending)
5161 seq_puts(m, ".descending");
5162 }
5163 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5164 if (hist_data->enable_timestamps)
5165 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5166
5167 print_actions_spec(m, hist_data);
5168
5169 if (data->filter_str)
5170 seq_printf(m, " if %s", data->filter_str);
5171
5172 if (data->paused)
5173 seq_puts(m, " [paused]");
5174 else
5175 seq_puts(m, " [active]");
5176
5177 seq_putc(m, '\n');
5178
5179 return 0;
5180 }
5181
5182 static int event_hist_trigger_init(struct event_trigger_ops *ops,
5183 struct event_trigger_data *data)
5184 {
5185 struct hist_trigger_data *hist_data = data->private_data;
5186
5187 if (!data->ref && hist_data->attrs->name)
5188 save_named_trigger(hist_data->attrs->name, data);
5189
5190 data->ref++;
5191
5192 return 0;
5193 }
5194
5195 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5196 {
5197 struct trace_event_file *file;
5198 unsigned int i;
5199 char *cmd;
5200 int ret;
5201
5202 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5203 file = hist_data->field_var_hists[i]->hist_data->event_file;
5204 cmd = hist_data->field_var_hists[i]->cmd;
5205 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
5206 "!hist", "hist", cmd);
5207 }
5208 }
5209
5210 static void event_hist_trigger_free(struct event_trigger_ops *ops,
5211 struct event_trigger_data *data)
5212 {
5213 struct hist_trigger_data *hist_data = data->private_data;
5214
5215 if (WARN_ON_ONCE(data->ref <= 0))
5216 return;
5217
5218 data->ref--;
5219 if (!data->ref) {
5220 if (data->name)
5221 del_named_trigger(data);
5222
5223 trigger_data_free(data);
5224
5225 remove_hist_vars(hist_data);
5226
5227 unregister_field_var_hists(hist_data);
5228
5229 destroy_hist_data(hist_data);
5230 }
5231 }
5232
5233 static struct event_trigger_ops event_hist_trigger_ops = {
5234 .func = event_hist_trigger,
5235 .print = event_hist_trigger_print,
5236 .init = event_hist_trigger_init,
5237 .free = event_hist_trigger_free,
5238 };
5239
5240 static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
5241 struct event_trigger_data *data)
5242 {
5243 data->ref++;
5244
5245 save_named_trigger(data->named_data->name, data);
5246
5247 event_hist_trigger_init(ops, data->named_data);
5248
5249 return 0;
5250 }
5251
5252 static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
5253 struct event_trigger_data *data)
5254 {
5255 if (WARN_ON_ONCE(data->ref <= 0))
5256 return;
5257
5258 event_hist_trigger_free(ops, data->named_data);
5259
5260 data->ref--;
5261 if (!data->ref) {
5262 del_named_trigger(data);
5263 trigger_data_free(data);
5264 }
5265 }
5266
5267 static struct event_trigger_ops event_hist_trigger_named_ops = {
5268 .func = event_hist_trigger,
5269 .print = event_hist_trigger_print,
5270 .init = event_hist_trigger_named_init,
5271 .free = event_hist_trigger_named_free,
5272 };
5273
5274 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5275 char *param)
5276 {
5277 return &event_hist_trigger_ops;
5278 }
5279
5280 static void hist_clear(struct event_trigger_data *data)
5281 {
5282 struct hist_trigger_data *hist_data = data->private_data;
5283
5284 if (data->name)
5285 pause_named_trigger(data);
5286
5287 tracepoint_synchronize_unregister();
5288
5289 tracing_map_clear(hist_data->map);
5290
5291 if (data->name)
5292 unpause_named_trigger(data);
5293 }
5294
5295 static bool compatible_field(struct ftrace_event_field *field,
5296 struct ftrace_event_field *test_field)
5297 {
5298 if (field == test_field)
5299 return true;
5300 if (field == NULL || test_field == NULL)
5301 return false;
5302 if (strcmp(field->name, test_field->name) != 0)
5303 return false;
5304 if (strcmp(field->type, test_field->type) != 0)
5305 return false;
5306 if (field->size != test_field->size)
5307 return false;
5308 if (field->is_signed != test_field->is_signed)
5309 return false;
5310
5311 return true;
5312 }
5313
5314 static bool hist_trigger_match(struct event_trigger_data *data,
5315 struct event_trigger_data *data_test,
5316 struct event_trigger_data *named_data,
5317 bool ignore_filter)
5318 {
5319 struct tracing_map_sort_key *sort_key, *sort_key_test;
5320 struct hist_trigger_data *hist_data, *hist_data_test;
5321 struct hist_field *key_field, *key_field_test;
5322 unsigned int i;
5323
5324 if (named_data && (named_data != data_test) &&
5325 (named_data != data_test->named_data))
5326 return false;
5327
5328 if (!named_data && is_named_trigger(data_test))
5329 return false;
5330
5331 hist_data = data->private_data;
5332 hist_data_test = data_test->private_data;
5333
5334 if (hist_data->n_vals != hist_data_test->n_vals ||
5335 hist_data->n_fields != hist_data_test->n_fields ||
5336 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5337 return false;
5338
5339 if (!ignore_filter) {
5340 if ((data->filter_str && !data_test->filter_str) ||
5341 (!data->filter_str && data_test->filter_str))
5342 return false;
5343 }
5344
5345 for_each_hist_field(i, hist_data) {
5346 key_field = hist_data->fields[i];
5347 key_field_test = hist_data_test->fields[i];
5348
5349 if (key_field->flags != key_field_test->flags)
5350 return false;
5351 if (!compatible_field(key_field->field, key_field_test->field))
5352 return false;
5353 if (key_field->offset != key_field_test->offset)
5354 return false;
5355 if (key_field->size != key_field_test->size)
5356 return false;
5357 if (key_field->is_signed != key_field_test->is_signed)
5358 return false;
5359 if (!!key_field->var.name != !!key_field_test->var.name)
5360 return false;
5361 if (key_field->var.name &&
5362 strcmp(key_field->var.name, key_field_test->var.name) != 0)
5363 return false;
5364 }
5365
5366 for (i = 0; i < hist_data->n_sort_keys; i++) {
5367 sort_key = &hist_data->sort_keys[i];
5368 sort_key_test = &hist_data_test->sort_keys[i];
5369
5370 if (sort_key->field_idx != sort_key_test->field_idx ||
5371 sort_key->descending != sort_key_test->descending)
5372 return false;
5373 }
5374
5375 if (!ignore_filter && data->filter_str &&
5376 (strcmp(data->filter_str, data_test->filter_str) != 0))
5377 return false;
5378
5379 if (!actions_match(hist_data, hist_data_test))
5380 return false;
5381
5382 return true;
5383 }
5384
5385 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
5386 struct event_trigger_data *data,
5387 struct trace_event_file *file)
5388 {
5389 struct hist_trigger_data *hist_data = data->private_data;
5390 struct event_trigger_data *test, *named_data = NULL;
5391 struct trace_array *tr = file->tr;
5392 int ret = 0;
5393
5394 if (hist_data->attrs->name) {
5395 named_data = find_named_trigger(hist_data->attrs->name);
5396 if (named_data) {
5397 if (!hist_trigger_match(data, named_data, named_data,
5398 true)) {
5399 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name));
5400 ret = -EINVAL;
5401 goto out;
5402 }
5403 }
5404 }
5405
5406 if (hist_data->attrs->name && !named_data)
5407 goto new;
5408
5409 lockdep_assert_held(&event_mutex);
5410
5411 list_for_each_entry(test, &file->triggers, list) {
5412 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5413 if (!hist_trigger_match(data, test, named_data, false))
5414 continue;
5415 if (hist_data->attrs->pause)
5416 test->paused = true;
5417 else if (hist_data->attrs->cont)
5418 test->paused = false;
5419 else if (hist_data->attrs->clear)
5420 hist_clear(test);
5421 else {
5422 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0);
5423 ret = -EEXIST;
5424 }
5425 goto out;
5426 }
5427 }
5428 new:
5429 if (hist_data->attrs->cont || hist_data->attrs->clear) {
5430 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0);
5431 ret = -ENOENT;
5432 goto out;
5433 }
5434
5435 if (hist_data->attrs->pause)
5436 data->paused = true;
5437
5438 if (named_data) {
5439 data->private_data = named_data->private_data;
5440 set_named_trigger_data(data, named_data);
5441 data->ops = &event_hist_trigger_named_ops;
5442 }
5443
5444 if (data->ops->init) {
5445 ret = data->ops->init(data->ops, data);
5446 if (ret < 0)
5447 goto out;
5448 }
5449
5450 if (hist_data->enable_timestamps) {
5451 char *clock = hist_data->attrs->clock;
5452
5453 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
5454 if (ret) {
5455 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock));
5456 goto out;
5457 }
5458
5459 tracing_set_time_stamp_abs(file->tr, true);
5460 }
5461
5462 if (named_data)
5463 destroy_hist_data(hist_data);
5464
5465 ret++;
5466 out:
5467 return ret;
5468 }
5469
5470 static int hist_trigger_enable(struct event_trigger_data *data,
5471 struct trace_event_file *file)
5472 {
5473 int ret = 0;
5474
5475 list_add_tail_rcu(&data->list, &file->triggers);
5476
5477 update_cond_flag(file);
5478
5479 if (trace_event_trigger_enable_disable(file, 1) < 0) {
5480 list_del_rcu(&data->list);
5481 update_cond_flag(file);
5482 ret--;
5483 }
5484
5485 return ret;
5486 }
5487
5488 static bool have_hist_trigger_match(struct event_trigger_data *data,
5489 struct trace_event_file *file)
5490 {
5491 struct hist_trigger_data *hist_data = data->private_data;
5492 struct event_trigger_data *test, *named_data = NULL;
5493 bool match = false;
5494
5495 lockdep_assert_held(&event_mutex);
5496
5497 if (hist_data->attrs->name)
5498 named_data = find_named_trigger(hist_data->attrs->name);
5499
5500 list_for_each_entry(test, &file->triggers, list) {
5501 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5502 if (hist_trigger_match(data, test, named_data, false)) {
5503 match = true;
5504 break;
5505 }
5506 }
5507 }
5508
5509 return match;
5510 }
5511
5512 static bool hist_trigger_check_refs(struct event_trigger_data *data,
5513 struct trace_event_file *file)
5514 {
5515 struct hist_trigger_data *hist_data = data->private_data;
5516 struct event_trigger_data *test, *named_data = NULL;
5517
5518 lockdep_assert_held(&event_mutex);
5519
5520 if (hist_data->attrs->name)
5521 named_data = find_named_trigger(hist_data->attrs->name);
5522
5523 list_for_each_entry(test, &file->triggers, list) {
5524 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5525 if (!hist_trigger_match(data, test, named_data, false))
5526 continue;
5527 hist_data = test->private_data;
5528 if (check_var_refs(hist_data))
5529 return true;
5530 break;
5531 }
5532 }
5533
5534 return false;
5535 }
5536
5537 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
5538 struct event_trigger_data *data,
5539 struct trace_event_file *file)
5540 {
5541 struct hist_trigger_data *hist_data = data->private_data;
5542 struct event_trigger_data *test, *named_data = NULL;
5543 bool unregistered = false;
5544
5545 lockdep_assert_held(&event_mutex);
5546
5547 if (hist_data->attrs->name)
5548 named_data = find_named_trigger(hist_data->attrs->name);
5549
5550 list_for_each_entry(test, &file->triggers, list) {
5551 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5552 if (!hist_trigger_match(data, test, named_data, false))
5553 continue;
5554 unregistered = true;
5555 list_del_rcu(&test->list);
5556 trace_event_trigger_enable_disable(file, 0);
5557 update_cond_flag(file);
5558 break;
5559 }
5560 }
5561
5562 if (unregistered && test->ops->free)
5563 test->ops->free(test->ops, test);
5564
5565 if (hist_data->enable_timestamps) {
5566 if (!hist_data->remove || unregistered)
5567 tracing_set_time_stamp_abs(file->tr, false);
5568 }
5569 }
5570
5571 static bool hist_file_check_refs(struct trace_event_file *file)
5572 {
5573 struct hist_trigger_data *hist_data;
5574 struct event_trigger_data *test;
5575
5576 lockdep_assert_held(&event_mutex);
5577
5578 list_for_each_entry(test, &file->triggers, list) {
5579 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5580 hist_data = test->private_data;
5581 if (check_var_refs(hist_data))
5582 return true;
5583 }
5584 }
5585
5586 return false;
5587 }
5588
5589 static void hist_unreg_all(struct trace_event_file *file)
5590 {
5591 struct event_trigger_data *test, *n;
5592 struct hist_trigger_data *hist_data;
5593 struct synth_event *se;
5594 const char *se_name;
5595
5596 lockdep_assert_held(&event_mutex);
5597
5598 if (hist_file_check_refs(file))
5599 return;
5600
5601 list_for_each_entry_safe(test, n, &file->triggers, list) {
5602 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5603 hist_data = test->private_data;
5604 list_del_rcu(&test->list);
5605 trace_event_trigger_enable_disable(file, 0);
5606
5607 se_name = trace_event_name(file->event_call);
5608 se = find_synth_event(se_name);
5609 if (se)
5610 se->ref--;
5611
5612 update_cond_flag(file);
5613 if (hist_data->enable_timestamps)
5614 tracing_set_time_stamp_abs(file->tr, false);
5615 if (test->ops->free)
5616 test->ops->free(test->ops, test);
5617 }
5618 }
5619 }
5620
5621 static int event_hist_trigger_func(struct event_command *cmd_ops,
5622 struct trace_event_file *file,
5623 char *glob, char *cmd, char *param)
5624 {
5625 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
5626 struct event_trigger_data *trigger_data;
5627 struct hist_trigger_attrs *attrs;
5628 struct event_trigger_ops *trigger_ops;
5629 struct hist_trigger_data *hist_data;
5630 struct synth_event *se;
5631 const char *se_name;
5632 bool remove = false;
5633 char *trigger, *p;
5634 int ret = 0;
5635
5636 lockdep_assert_held(&event_mutex);
5637
5638 if (glob && strlen(glob)) {
5639 hist_err_clear();
5640 last_cmd_set(file, param);
5641 }
5642
5643 if (!param)
5644 return -EINVAL;
5645
5646 if (glob[0] == '!')
5647 remove = true;
5648
5649 /*
5650 * separate the trigger from the filter (k:v [if filter])
5651 * allowing for whitespace in the trigger
5652 */
5653 p = trigger = param;
5654 do {
5655 p = strstr(p, "if");
5656 if (!p)
5657 break;
5658 if (p == param)
5659 return -EINVAL;
5660 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
5661 p++;
5662 continue;
5663 }
5664 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1)
5665 return -EINVAL;
5666 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
5667 p++;
5668 continue;
5669 }
5670 break;
5671 } while (p);
5672
5673 if (!p)
5674 param = NULL;
5675 else {
5676 *(p - 1) = '\0';
5677 param = strstrip(p);
5678 trigger = strstrip(trigger);
5679 }
5680
5681 attrs = parse_hist_trigger_attrs(file->tr, trigger);
5682 if (IS_ERR(attrs))
5683 return PTR_ERR(attrs);
5684
5685 if (attrs->map_bits)
5686 hist_trigger_bits = attrs->map_bits;
5687
5688 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
5689 if (IS_ERR(hist_data)) {
5690 destroy_hist_trigger_attrs(attrs);
5691 return PTR_ERR(hist_data);
5692 }
5693
5694 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
5695
5696 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
5697 if (!trigger_data) {
5698 ret = -ENOMEM;
5699 goto out_free;
5700 }
5701
5702 trigger_data->count = -1;
5703 trigger_data->ops = trigger_ops;
5704 trigger_data->cmd_ops = cmd_ops;
5705
5706 INIT_LIST_HEAD(&trigger_data->list);
5707 RCU_INIT_POINTER(trigger_data->filter, NULL);
5708
5709 trigger_data->private_data = hist_data;
5710
5711 /* if param is non-empty, it's supposed to be a filter */
5712 if (param && cmd_ops->set_filter) {
5713 ret = cmd_ops->set_filter(param, trigger_data, file);
5714 if (ret < 0)
5715 goto out_free;
5716 }
5717
5718 if (remove) {
5719 if (!have_hist_trigger_match(trigger_data, file))
5720 goto out_free;
5721
5722 if (hist_trigger_check_refs(trigger_data, file)) {
5723 ret = -EBUSY;
5724 goto out_free;
5725 }
5726
5727 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5728 se_name = trace_event_name(file->event_call);
5729 se = find_synth_event(se_name);
5730 if (se)
5731 se->ref--;
5732 ret = 0;
5733 goto out_free;
5734 }
5735
5736 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
5737 /*
5738 * The above returns on success the # of triggers registered,
5739 * but if it didn't register any it returns zero. Consider no
5740 * triggers registered a failure too.
5741 */
5742 if (!ret) {
5743 if (!(attrs->pause || attrs->cont || attrs->clear))
5744 ret = -ENOENT;
5745 goto out_free;
5746 } else if (ret < 0)
5747 goto out_free;
5748
5749 if (get_named_trigger_data(trigger_data))
5750 goto enable;
5751
5752 if (has_hist_vars(hist_data))
5753 save_hist_vars(hist_data);
5754
5755 ret = create_actions(hist_data);
5756 if (ret)
5757 goto out_unreg;
5758
5759 ret = tracing_map_init(hist_data->map);
5760 if (ret)
5761 goto out_unreg;
5762 enable:
5763 ret = hist_trigger_enable(trigger_data, file);
5764 if (ret)
5765 goto out_unreg;
5766
5767 se_name = trace_event_name(file->event_call);
5768 se = find_synth_event(se_name);
5769 if (se)
5770 se->ref++;
5771 /* Just return zero, not the number of registered triggers */
5772 ret = 0;
5773 out:
5774 if (ret == 0)
5775 hist_err_clear();
5776
5777 return ret;
5778 out_unreg:
5779 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5780 out_free:
5781 if (cmd_ops->set_filter)
5782 cmd_ops->set_filter(NULL, trigger_data, NULL);
5783
5784 remove_hist_vars(hist_data);
5785
5786 kfree(trigger_data);
5787
5788 destroy_hist_data(hist_data);
5789 goto out;
5790 }
5791
5792 static struct event_command trigger_hist_cmd = {
5793 .name = "hist",
5794 .trigger_type = ETT_EVENT_HIST,
5795 .flags = EVENT_CMD_FL_NEEDS_REC,
5796 .func = event_hist_trigger_func,
5797 .reg = hist_register_trigger,
5798 .unreg = hist_unregister_trigger,
5799 .unreg_all = hist_unreg_all,
5800 .get_trigger_ops = event_hist_get_trigger_ops,
5801 .set_filter = set_trigger_filter,
5802 };
5803
5804 __init int register_trigger_hist_cmd(void)
5805 {
5806 int ret;
5807
5808 ret = register_event_command(&trigger_hist_cmd);
5809 WARN_ON(ret < 0);
5810
5811 return ret;
5812 }
5813
5814 static void
5815 hist_enable_trigger(struct event_trigger_data *data, void *rec,
5816 struct ring_buffer_event *event)
5817 {
5818 struct enable_trigger_data *enable_data = data->private_data;
5819 struct event_trigger_data *test;
5820
5821 list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
5822 lockdep_is_held(&event_mutex)) {
5823 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5824 if (enable_data->enable)
5825 test->paused = false;
5826 else
5827 test->paused = true;
5828 }
5829 }
5830 }
5831
5832 static void
5833 hist_enable_count_trigger(struct event_trigger_data *data, void *rec,
5834 struct ring_buffer_event *event)
5835 {
5836 if (!data->count)
5837 return;
5838
5839 if (data->count != -1)
5840 (data->count)--;
5841
5842 hist_enable_trigger(data, rec, event);
5843 }
5844
5845 static struct event_trigger_ops hist_enable_trigger_ops = {
5846 .func = hist_enable_trigger,
5847 .print = event_enable_trigger_print,
5848 .init = event_trigger_init,
5849 .free = event_enable_trigger_free,
5850 };
5851
5852 static struct event_trigger_ops hist_enable_count_trigger_ops = {
5853 .func = hist_enable_count_trigger,
5854 .print = event_enable_trigger_print,
5855 .init = event_trigger_init,
5856 .free = event_enable_trigger_free,
5857 };
5858
5859 static struct event_trigger_ops hist_disable_trigger_ops = {
5860 .func = hist_enable_trigger,
5861 .print = event_enable_trigger_print,
5862 .init = event_trigger_init,
5863 .free = event_enable_trigger_free,
5864 };
5865
5866 static struct event_trigger_ops hist_disable_count_trigger_ops = {
5867 .func = hist_enable_count_trigger,
5868 .print = event_enable_trigger_print,
5869 .init = event_trigger_init,
5870 .free = event_enable_trigger_free,
5871 };
5872
5873 static struct event_trigger_ops *
5874 hist_enable_get_trigger_ops(char *cmd, char *param)
5875 {
5876 struct event_trigger_ops *ops;
5877 bool enable;
5878
5879 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
5880
5881 if (enable)
5882 ops = param ? &hist_enable_count_trigger_ops :
5883 &hist_enable_trigger_ops;
5884 else
5885 ops = param ? &hist_disable_count_trigger_ops :
5886 &hist_disable_trigger_ops;
5887
5888 return ops;
5889 }
5890
5891 static void hist_enable_unreg_all(struct trace_event_file *file)
5892 {
5893 struct event_trigger_data *test, *n;
5894
5895 list_for_each_entry_safe(test, n, &file->triggers, list) {
5896 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
5897 list_del_rcu(&test->list);
5898 update_cond_flag(file);
5899 trace_event_trigger_enable_disable(file, 0);
5900 if (test->ops->free)
5901 test->ops->free(test->ops, test);
5902 }
5903 }
5904 }
5905
5906 static struct event_command trigger_hist_enable_cmd = {
5907 .name = ENABLE_HIST_STR,
5908 .trigger_type = ETT_HIST_ENABLE,
5909 .func = event_enable_trigger_func,
5910 .reg = event_enable_register_trigger,
5911 .unreg = event_enable_unregister_trigger,
5912 .unreg_all = hist_enable_unreg_all,
5913 .get_trigger_ops = hist_enable_get_trigger_ops,
5914 .set_filter = set_trigger_filter,
5915 };
5916
5917 static struct event_command trigger_hist_disable_cmd = {
5918 .name = DISABLE_HIST_STR,
5919 .trigger_type = ETT_HIST_ENABLE,
5920 .func = event_enable_trigger_func,
5921 .reg = event_enable_register_trigger,
5922 .unreg = event_enable_unregister_trigger,
5923 .unreg_all = hist_enable_unreg_all,
5924 .get_trigger_ops = hist_enable_get_trigger_ops,
5925 .set_filter = set_trigger_filter,
5926 };
5927
5928 static __init void unregister_trigger_hist_enable_disable_cmds(void)
5929 {
5930 unregister_event_command(&trigger_hist_enable_cmd);
5931 unregister_event_command(&trigger_hist_disable_cmd);
5932 }
5933
5934 __init int register_trigger_hist_enable_disable_cmds(void)
5935 {
5936 int ret;
5937
5938 ret = register_event_command(&trigger_hist_enable_cmd);
5939 if (WARN_ON(ret < 0))
5940 return ret;
5941 ret = register_event_command(&trigger_hist_disable_cmd);
5942 if (WARN_ON(ret < 0))
5943 unregister_trigger_hist_enable_disable_cmds();
5944
5945 return ret;
5946 }
Linux with added FPC-III support