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 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"),
70
71 #undef C
72 #define C(a, b) HIST_ERR_##a
73
74 enum { ERRORS };
75
76 #undef C
77 #define C(a, b) b
78
79 static const char *err_text[] = { ERRORS };
80
81 struct hist_field;
82
83 typedef u64 (*hist_field_fn_t) (struct hist_field *field,
84 struct tracing_map_elt *elt,
85 struct ring_buffer_event *rbe,
86 void *event);
87
88 #define HIST_FIELD_OPERANDS_MAX 2
89 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
90 #define HIST_ACTIONS_MAX 8
91
92 enum field_op_id {
93 FIELD_OP_NONE,
94 FIELD_OP_PLUS,
95 FIELD_OP_MINUS,
96 FIELD_OP_UNARY_MINUS,
97 };
98
99 /*
100 * A hist_var (histogram variable) contains variable information for
101 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF
102 * flag set. A hist_var has a variable name e.g. ts0, and is
103 * associated with a given histogram trigger, as specified by
104 * hist_data. The hist_var idx is the unique index assigned to the
105 * variable by the hist trigger's tracing_map. The idx is what is
106 * used to set a variable's value and, by a variable reference, to
107 * retrieve it.
108 */
109 struct hist_var {
110 char *name;
111 struct hist_trigger_data *hist_data;
112 unsigned int idx;
113 };
114
115 struct hist_field {
116 struct ftrace_event_field *field;
117 unsigned long flags;
118 hist_field_fn_t fn;
119 unsigned int ref;
120 unsigned int size;
121 unsigned int offset;
122 unsigned int is_signed;
123 const char *type;
124 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
125 struct hist_trigger_data *hist_data;
126
127 /*
128 * Variable fields contain variable-specific info in var.
129 */
130 struct hist_var var;
131 enum field_op_id operator;
132 char *system;
133 char *event_name;
134
135 /*
136 * The name field is used for EXPR and VAR_REF fields. VAR
137 * fields contain the variable name in var.name.
138 */
139 char *name;
140
141 /*
142 * When a histogram trigger is hit, if it has any references
143 * to variables, the values of those variables are collected
144 * into a var_ref_vals array by resolve_var_refs(). The
145 * current value of each variable is read from the tracing_map
146 * using the hist field's hist_var.idx and entered into the
147 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx].
148 */
149 unsigned int var_ref_idx;
150 bool read_once;
151
152 unsigned int var_str_idx;
153 };
154
hist_field_none(struct hist_field * field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)155 static u64 hist_field_none(struct hist_field *field,
156 struct tracing_map_elt *elt,
157 struct ring_buffer_event *rbe,
158 void *event)
159 {
160 return 0;
161 }
162
hist_field_counter(struct hist_field * field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)163 static u64 hist_field_counter(struct hist_field *field,
164 struct tracing_map_elt *elt,
165 struct ring_buffer_event *rbe,
166 void *event)
167 {
168 return 1;
169 }
170
hist_field_string(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)171 static u64 hist_field_string(struct hist_field *hist_field,
172 struct tracing_map_elt *elt,
173 struct ring_buffer_event *rbe,
174 void *event)
175 {
176 char *addr = (char *)(event + hist_field->field->offset);
177
178 return (u64)(unsigned long)addr;
179 }
180
hist_field_dynstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)181 static u64 hist_field_dynstring(struct hist_field *hist_field,
182 struct tracing_map_elt *elt,
183 struct ring_buffer_event *rbe,
184 void *event)
185 {
186 u32 str_item = *(u32 *)(event + hist_field->field->offset);
187 int str_loc = str_item & 0xffff;
188 char *addr = (char *)(event + str_loc);
189
190 return (u64)(unsigned long)addr;
191 }
192
hist_field_pstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)193 static u64 hist_field_pstring(struct hist_field *hist_field,
194 struct tracing_map_elt *elt,
195 struct ring_buffer_event *rbe,
196 void *event)
197 {
198 char **addr = (char **)(event + hist_field->field->offset);
199
200 return (u64)(unsigned long)*addr;
201 }
202
hist_field_log2(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)203 static u64 hist_field_log2(struct hist_field *hist_field,
204 struct tracing_map_elt *elt,
205 struct ring_buffer_event *rbe,
206 void *event)
207 {
208 struct hist_field *operand = hist_field->operands[0];
209
210 u64 val = operand->fn(operand, elt, rbe, event);
211
212 return (u64) ilog2(roundup_pow_of_two(val));
213 }
214
hist_field_plus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)215 static u64 hist_field_plus(struct hist_field *hist_field,
216 struct tracing_map_elt *elt,
217 struct ring_buffer_event *rbe,
218 void *event)
219 {
220 struct hist_field *operand1 = hist_field->operands[0];
221 struct hist_field *operand2 = hist_field->operands[1];
222
223 u64 val1 = operand1->fn(operand1, elt, rbe, event);
224 u64 val2 = operand2->fn(operand2, elt, rbe, event);
225
226 return val1 + val2;
227 }
228
hist_field_minus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)229 static u64 hist_field_minus(struct hist_field *hist_field,
230 struct tracing_map_elt *elt,
231 struct ring_buffer_event *rbe,
232 void *event)
233 {
234 struct hist_field *operand1 = hist_field->operands[0];
235 struct hist_field *operand2 = hist_field->operands[1];
236
237 u64 val1 = operand1->fn(operand1, elt, rbe, event);
238 u64 val2 = operand2->fn(operand2, elt, rbe, event);
239
240 return val1 - val2;
241 }
242
hist_field_unary_minus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)243 static u64 hist_field_unary_minus(struct hist_field *hist_field,
244 struct tracing_map_elt *elt,
245 struct ring_buffer_event *rbe,
246 void *event)
247 {
248 struct hist_field *operand = hist_field->operands[0];
249
250 s64 sval = (s64)operand->fn(operand, elt, rbe, event);
251 u64 val = (u64)-sval;
252
253 return val;
254 }
255
256 #define DEFINE_HIST_FIELD_FN(type) \
257 static u64 hist_field_##type(struct hist_field *hist_field, \
258 struct tracing_map_elt *elt, \
259 struct ring_buffer_event *rbe, \
260 void *event) \
261 { \
262 type *addr = (type *)(event + hist_field->field->offset); \
263 \
264 return (u64)(unsigned long)*addr; \
265 }
266
267 DEFINE_HIST_FIELD_FN(s64);
268 DEFINE_HIST_FIELD_FN(u64);
269 DEFINE_HIST_FIELD_FN(s32);
270 DEFINE_HIST_FIELD_FN(u32);
271 DEFINE_HIST_FIELD_FN(s16);
272 DEFINE_HIST_FIELD_FN(u16);
273 DEFINE_HIST_FIELD_FN(s8);
274 DEFINE_HIST_FIELD_FN(u8);
275
276 #define for_each_hist_field(i, hist_data) \
277 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
278
279 #define for_each_hist_val_field(i, hist_data) \
280 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
281
282 #define for_each_hist_key_field(i, hist_data) \
283 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
284
285 #define HIST_STACKTRACE_DEPTH 16
286 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
287 #define HIST_STACKTRACE_SKIP 5
288
289 #define HITCOUNT_IDX 0
290 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
291
292 enum hist_field_flags {
293 HIST_FIELD_FL_HITCOUNT = 1 << 0,
294 HIST_FIELD_FL_KEY = 1 << 1,
295 HIST_FIELD_FL_STRING = 1 << 2,
296 HIST_FIELD_FL_HEX = 1 << 3,
297 HIST_FIELD_FL_SYM = 1 << 4,
298 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
299 HIST_FIELD_FL_EXECNAME = 1 << 6,
300 HIST_FIELD_FL_SYSCALL = 1 << 7,
301 HIST_FIELD_FL_STACKTRACE = 1 << 8,
302 HIST_FIELD_FL_LOG2 = 1 << 9,
303 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
304 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
305 HIST_FIELD_FL_VAR = 1 << 12,
306 HIST_FIELD_FL_EXPR = 1 << 13,
307 HIST_FIELD_FL_VAR_REF = 1 << 14,
308 HIST_FIELD_FL_CPU = 1 << 15,
309 HIST_FIELD_FL_ALIAS = 1 << 16,
310 };
311
312 struct var_defs {
313 unsigned int n_vars;
314 char *name[TRACING_MAP_VARS_MAX];
315 char *expr[TRACING_MAP_VARS_MAX];
316 };
317
318 struct hist_trigger_attrs {
319 char *keys_str;
320 char *vals_str;
321 char *sort_key_str;
322 char *name;
323 char *clock;
324 bool pause;
325 bool cont;
326 bool clear;
327 bool ts_in_usecs;
328 unsigned int map_bits;
329
330 char *assignment_str[TRACING_MAP_VARS_MAX];
331 unsigned int n_assignments;
332
333 char *action_str[HIST_ACTIONS_MAX];
334 unsigned int n_actions;
335
336 struct var_defs var_defs;
337 };
338
339 struct field_var {
340 struct hist_field *var;
341 struct hist_field *val;
342 };
343
344 struct field_var_hist {
345 struct hist_trigger_data *hist_data;
346 char *cmd;
347 };
348
349 struct hist_trigger_data {
350 struct hist_field *fields[HIST_FIELDS_MAX];
351 unsigned int n_vals;
352 unsigned int n_keys;
353 unsigned int n_fields;
354 unsigned int n_vars;
355 unsigned int n_var_str;
356 unsigned int key_size;
357 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
358 unsigned int n_sort_keys;
359 struct trace_event_file *event_file;
360 struct hist_trigger_attrs *attrs;
361 struct tracing_map *map;
362 bool enable_timestamps;
363 bool remove;
364 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
365 unsigned int n_var_refs;
366
367 struct action_data *actions[HIST_ACTIONS_MAX];
368 unsigned int n_actions;
369
370 struct field_var *field_vars[SYNTH_FIELDS_MAX];
371 unsigned int n_field_vars;
372 unsigned int n_field_var_str;
373 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
374 unsigned int n_field_var_hists;
375
376 struct field_var *save_vars[SYNTH_FIELDS_MAX];
377 unsigned int n_save_vars;
378 unsigned int n_save_var_str;
379 };
380
381 struct action_data;
382
383 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
384 struct tracing_map_elt *elt, void *rec,
385 struct ring_buffer_event *rbe, void *key,
386 struct action_data *data, u64 *var_ref_vals);
387
388 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val);
389
390 enum handler_id {
391 HANDLER_ONMATCH = 1,
392 HANDLER_ONMAX,
393 HANDLER_ONCHANGE,
394 };
395
396 enum action_id {
397 ACTION_SAVE = 1,
398 ACTION_TRACE,
399 ACTION_SNAPSHOT,
400 };
401
402 struct action_data {
403 enum handler_id handler;
404 enum action_id action;
405 char *action_name;
406 action_fn_t fn;
407
408 unsigned int n_params;
409 char *params[SYNTH_FIELDS_MAX];
410
411 /*
412 * When a histogram trigger is hit, the values of any
413 * references to variables, including variables being passed
414 * as parameters to synthetic events, are collected into a
415 * var_ref_vals array. This var_ref_idx array is an array of
416 * indices into the var_ref_vals array, one for each synthetic
417 * event param, and is passed to the synthetic event
418 * invocation.
419 */
420 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX];
421 struct synth_event *synth_event;
422 bool use_trace_keyword;
423 char *synth_event_name;
424
425 union {
426 struct {
427 char *event;
428 char *event_system;
429 } match_data;
430
431 struct {
432 /*
433 * var_str contains the $-unstripped variable
434 * name referenced by var_ref, and used when
435 * printing the action. Because var_ref
436 * creation is deferred to create_actions(),
437 * we need a per-action way to save it until
438 * then, thus var_str.
439 */
440 char *var_str;
441
442 /*
443 * var_ref refers to the variable being
444 * tracked e.g onmax($var).
445 */
446 struct hist_field *var_ref;
447
448 /*
449 * track_var contains the 'invisible' tracking
450 * variable created to keep the current
451 * e.g. max value.
452 */
453 struct hist_field *track_var;
454
455 check_track_val_fn_t check_val;
456 action_fn_t save_data;
457 } track_data;
458 };
459 };
460
461 struct track_data {
462 u64 track_val;
463 bool updated;
464
465 unsigned int key_len;
466 void *key;
467 struct tracing_map_elt elt;
468
469 struct action_data *action_data;
470 struct hist_trigger_data *hist_data;
471 };
472
473 struct hist_elt_data {
474 char *comm;
475 u64 *var_ref_vals;
476 char *field_var_str[SYNTH_FIELDS_MAX];
477 };
478
479 struct snapshot_context {
480 struct tracing_map_elt *elt;
481 void *key;
482 };
483
track_data_free(struct track_data * track_data)484 static void track_data_free(struct track_data *track_data)
485 {
486 struct hist_elt_data *elt_data;
487
488 if (!track_data)
489 return;
490
491 kfree(track_data->key);
492
493 elt_data = track_data->elt.private_data;
494 if (elt_data) {
495 kfree(elt_data->comm);
496 kfree(elt_data);
497 }
498
499 kfree(track_data);
500 }
501
track_data_alloc(unsigned int key_len,struct action_data * action_data,struct hist_trigger_data * hist_data)502 static struct track_data *track_data_alloc(unsigned int key_len,
503 struct action_data *action_data,
504 struct hist_trigger_data *hist_data)
505 {
506 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
507 struct hist_elt_data *elt_data;
508
509 if (!data)
510 return ERR_PTR(-ENOMEM);
511
512 data->key = kzalloc(key_len, GFP_KERNEL);
513 if (!data->key) {
514 track_data_free(data);
515 return ERR_PTR(-ENOMEM);
516 }
517
518 data->key_len = key_len;
519 data->action_data = action_data;
520 data->hist_data = hist_data;
521
522 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
523 if (!elt_data) {
524 track_data_free(data);
525 return ERR_PTR(-ENOMEM);
526 }
527
528 data->elt.private_data = elt_data;
529
530 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL);
531 if (!elt_data->comm) {
532 track_data_free(data);
533 return ERR_PTR(-ENOMEM);
534 }
535
536 return data;
537 }
538
539 static char last_cmd[MAX_FILTER_STR_VAL];
540 static char last_cmd_loc[MAX_FILTER_STR_VAL];
541
errpos(char * str)542 static int errpos(char *str)
543 {
544 return err_pos(last_cmd, str);
545 }
546
last_cmd_set(struct trace_event_file * file,char * str)547 static void last_cmd_set(struct trace_event_file *file, char *str)
548 {
549 const char *system = NULL, *name = NULL;
550 struct trace_event_call *call;
551
552 if (!str)
553 return;
554
555 strcpy(last_cmd, "hist:");
556 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:"));
557
558 if (file) {
559 call = file->event_call;
560 system = call->class->system;
561 if (system) {
562 name = trace_event_name(call);
563 if (!name)
564 system = NULL;
565 }
566 }
567
568 if (system)
569 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name);
570 }
571
hist_err(struct trace_array * tr,u8 err_type,u8 err_pos)572 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos)
573 {
574 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,
575 err_type, err_pos);
576 }
577
hist_err_clear(void)578 static void hist_err_clear(void)
579 {
580 last_cmd[0] = '\0';
581 last_cmd_loc[0] = '\0';
582 }
583
584 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
585 unsigned int *var_ref_idx);
586
trace_synth(struct synth_event * event,u64 * var_ref_vals,unsigned int * var_ref_idx)587 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
588 unsigned int *var_ref_idx)
589 {
590 struct tracepoint *tp = event->tp;
591
592 if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
593 struct tracepoint_func *probe_func_ptr;
594 synth_probe_func_t probe_func;
595 void *__data;
596
597 if (!(cpu_online(raw_smp_processor_id())))
598 return;
599
600 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
601 if (probe_func_ptr) {
602 do {
603 probe_func = probe_func_ptr->func;
604 __data = probe_func_ptr->data;
605 probe_func(__data, var_ref_vals, var_ref_idx);
606 } while ((++probe_func_ptr)->func);
607 }
608 }
609 }
610
action_trace(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)611 static void action_trace(struct hist_trigger_data *hist_data,
612 struct tracing_map_elt *elt, void *rec,
613 struct ring_buffer_event *rbe, void *key,
614 struct action_data *data, u64 *var_ref_vals)
615 {
616 struct synth_event *event = data->synth_event;
617
618 trace_synth(event, var_ref_vals, data->var_ref_idx);
619 }
620
621 struct hist_var_data {
622 struct list_head list;
623 struct hist_trigger_data *hist_data;
624 };
625
hist_field_timestamp(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)626 static u64 hist_field_timestamp(struct hist_field *hist_field,
627 struct tracing_map_elt *elt,
628 struct ring_buffer_event *rbe,
629 void *event)
630 {
631 struct hist_trigger_data *hist_data = hist_field->hist_data;
632 struct trace_array *tr = hist_data->event_file->tr;
633
634 u64 ts = ring_buffer_event_time_stamp(rbe);
635
636 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
637 ts = ns2usecs(ts);
638
639 return ts;
640 }
641
hist_field_cpu(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)642 static u64 hist_field_cpu(struct hist_field *hist_field,
643 struct tracing_map_elt *elt,
644 struct ring_buffer_event *rbe,
645 void *event)
646 {
647 int cpu = smp_processor_id();
648
649 return cpu;
650 }
651
652 /**
653 * check_field_for_var_ref - Check if a VAR_REF field references a variable
654 * @hist_field: The VAR_REF field to check
655 * @var_data: The hist trigger that owns the variable
656 * @var_idx: The trigger variable identifier
657 *
658 * Check the given VAR_REF field to see whether or not it references
659 * the given variable associated with the given trigger.
660 *
661 * Return: The VAR_REF field if it does reference the variable, NULL if not
662 */
663 static struct hist_field *
check_field_for_var_ref(struct hist_field * hist_field,struct hist_trigger_data * var_data,unsigned int var_idx)664 check_field_for_var_ref(struct hist_field *hist_field,
665 struct hist_trigger_data *var_data,
666 unsigned int var_idx)
667 {
668 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF));
669
670 if (hist_field && hist_field->var.idx == var_idx &&
671 hist_field->var.hist_data == var_data)
672 return hist_field;
673
674 return NULL;
675 }
676
677 /**
678 * find_var_ref - Check if a trigger has a reference to a trigger variable
679 * @hist_data: The hist trigger that might have a reference to the variable
680 * @var_data: The hist trigger that owns the variable
681 * @var_idx: The trigger variable identifier
682 *
683 * Check the list of var_refs[] on the first hist trigger to see
684 * whether any of them are references to the variable on the second
685 * trigger.
686 *
687 * Return: The VAR_REF field referencing the variable if so, NULL if not
688 */
find_var_ref(struct hist_trigger_data * hist_data,struct hist_trigger_data * var_data,unsigned int var_idx)689 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
690 struct hist_trigger_data *var_data,
691 unsigned int var_idx)
692 {
693 struct hist_field *hist_field;
694 unsigned int i;
695
696 for (i = 0; i < hist_data->n_var_refs; i++) {
697 hist_field = hist_data->var_refs[i];
698 if (check_field_for_var_ref(hist_field, var_data, var_idx))
699 return hist_field;
700 }
701
702 return NULL;
703 }
704
705 /**
706 * find_any_var_ref - Check if there is a reference to a given trigger variable
707 * @hist_data: The hist trigger
708 * @var_idx: The trigger variable identifier
709 *
710 * Check to see whether the given variable is currently referenced by
711 * any other trigger.
712 *
713 * The trigger the variable is defined on is explicitly excluded - the
714 * assumption being that a self-reference doesn't prevent a trigger
715 * from being removed.
716 *
717 * Return: The VAR_REF field referencing the variable if so, NULL if not
718 */
find_any_var_ref(struct hist_trigger_data * hist_data,unsigned int var_idx)719 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
720 unsigned int var_idx)
721 {
722 struct trace_array *tr = hist_data->event_file->tr;
723 struct hist_field *found = NULL;
724 struct hist_var_data *var_data;
725
726 list_for_each_entry(var_data, &tr->hist_vars, list) {
727 if (var_data->hist_data == hist_data)
728 continue;
729 found = find_var_ref(var_data->hist_data, hist_data, var_idx);
730 if (found)
731 break;
732 }
733
734 return found;
735 }
736
737 /**
738 * check_var_refs - Check if there is a reference to any of trigger's variables
739 * @hist_data: The hist trigger
740 *
741 * A trigger can define one or more variables. If any one of them is
742 * currently referenced by any other trigger, this function will
743 * determine that.
744
745 * Typically used to determine whether or not a trigger can be removed
746 * - if there are any references to a trigger's variables, it cannot.
747 *
748 * Return: True if there is a reference to any of trigger's variables
749 */
check_var_refs(struct hist_trigger_data * hist_data)750 static bool check_var_refs(struct hist_trigger_data *hist_data)
751 {
752 struct hist_field *field;
753 bool found = false;
754 int i;
755
756 for_each_hist_field(i, hist_data) {
757 field = hist_data->fields[i];
758 if (field && field->flags & HIST_FIELD_FL_VAR) {
759 if (find_any_var_ref(hist_data, field->var.idx)) {
760 found = true;
761 break;
762 }
763 }
764 }
765
766 return found;
767 }
768
find_hist_vars(struct hist_trigger_data * hist_data)769 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
770 {
771 struct trace_array *tr = hist_data->event_file->tr;
772 struct hist_var_data *var_data, *found = NULL;
773
774 list_for_each_entry(var_data, &tr->hist_vars, list) {
775 if (var_data->hist_data == hist_data) {
776 found = var_data;
777 break;
778 }
779 }
780
781 return found;
782 }
783
field_has_hist_vars(struct hist_field * hist_field,unsigned int level)784 static bool field_has_hist_vars(struct hist_field *hist_field,
785 unsigned int level)
786 {
787 int i;
788
789 if (level > 3)
790 return false;
791
792 if (!hist_field)
793 return false;
794
795 if (hist_field->flags & HIST_FIELD_FL_VAR ||
796 hist_field->flags & HIST_FIELD_FL_VAR_REF)
797 return true;
798
799 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
800 struct hist_field *operand;
801
802 operand = hist_field->operands[i];
803 if (field_has_hist_vars(operand, level + 1))
804 return true;
805 }
806
807 return false;
808 }
809
has_hist_vars(struct hist_trigger_data * hist_data)810 static bool has_hist_vars(struct hist_trigger_data *hist_data)
811 {
812 struct hist_field *hist_field;
813 int i;
814
815 for_each_hist_field(i, hist_data) {
816 hist_field = hist_data->fields[i];
817 if (field_has_hist_vars(hist_field, 0))
818 return true;
819 }
820
821 return false;
822 }
823
save_hist_vars(struct hist_trigger_data * hist_data)824 static int save_hist_vars(struct hist_trigger_data *hist_data)
825 {
826 struct trace_array *tr = hist_data->event_file->tr;
827 struct hist_var_data *var_data;
828
829 var_data = find_hist_vars(hist_data);
830 if (var_data)
831 return 0;
832
833 if (tracing_check_open_get_tr(tr))
834 return -ENODEV;
835
836 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
837 if (!var_data) {
838 trace_array_put(tr);
839 return -ENOMEM;
840 }
841
842 var_data->hist_data = hist_data;
843 list_add(&var_data->list, &tr->hist_vars);
844
845 return 0;
846 }
847
remove_hist_vars(struct hist_trigger_data * hist_data)848 static void remove_hist_vars(struct hist_trigger_data *hist_data)
849 {
850 struct trace_array *tr = hist_data->event_file->tr;
851 struct hist_var_data *var_data;
852
853 var_data = find_hist_vars(hist_data);
854 if (!var_data)
855 return;
856
857 if (WARN_ON(check_var_refs(hist_data)))
858 return;
859
860 list_del(&var_data->list);
861
862 kfree(var_data);
863
864 trace_array_put(tr);
865 }
866
find_var_field(struct hist_trigger_data * hist_data,const char * var_name)867 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
868 const char *var_name)
869 {
870 struct hist_field *hist_field, *found = NULL;
871 int i;
872
873 for_each_hist_field(i, hist_data) {
874 hist_field = hist_data->fields[i];
875 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
876 strcmp(hist_field->var.name, var_name) == 0) {
877 found = hist_field;
878 break;
879 }
880 }
881
882 return found;
883 }
884
find_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,const char * var_name)885 static struct hist_field *find_var(struct hist_trigger_data *hist_data,
886 struct trace_event_file *file,
887 const char *var_name)
888 {
889 struct hist_trigger_data *test_data;
890 struct event_trigger_data *test;
891 struct hist_field *hist_field;
892
893 lockdep_assert_held(&event_mutex);
894
895 hist_field = find_var_field(hist_data, var_name);
896 if (hist_field)
897 return hist_field;
898
899 list_for_each_entry(test, &file->triggers, list) {
900 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
901 test_data = test->private_data;
902 hist_field = find_var_field(test_data, var_name);
903 if (hist_field)
904 return hist_field;
905 }
906 }
907
908 return NULL;
909 }
910
find_var_file(struct trace_array * tr,char * system,char * event_name,char * var_name)911 static struct trace_event_file *find_var_file(struct trace_array *tr,
912 char *system,
913 char *event_name,
914 char *var_name)
915 {
916 struct hist_trigger_data *var_hist_data;
917 struct hist_var_data *var_data;
918 struct trace_event_file *file, *found = NULL;
919
920 if (system)
921 return find_event_file(tr, system, event_name);
922
923 list_for_each_entry(var_data, &tr->hist_vars, list) {
924 var_hist_data = var_data->hist_data;
925 file = var_hist_data->event_file;
926 if (file == found)
927 continue;
928
929 if (find_var_field(var_hist_data, var_name)) {
930 if (found) {
931 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name));
932 return NULL;
933 }
934
935 found = file;
936 }
937 }
938
939 return found;
940 }
941
find_file_var(struct trace_event_file * file,const char * var_name)942 static struct hist_field *find_file_var(struct trace_event_file *file,
943 const char *var_name)
944 {
945 struct hist_trigger_data *test_data;
946 struct event_trigger_data *test;
947 struct hist_field *hist_field;
948
949 lockdep_assert_held(&event_mutex);
950
951 list_for_each_entry(test, &file->triggers, list) {
952 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
953 test_data = test->private_data;
954 hist_field = find_var_field(test_data, var_name);
955 if (hist_field)
956 return hist_field;
957 }
958 }
959
960 return NULL;
961 }
962
963 static struct hist_field *
find_match_var(struct hist_trigger_data * hist_data,char * var_name)964 find_match_var(struct hist_trigger_data *hist_data, char *var_name)
965 {
966 struct trace_array *tr = hist_data->event_file->tr;
967 struct hist_field *hist_field, *found = NULL;
968 struct trace_event_file *file;
969 unsigned int i;
970
971 for (i = 0; i < hist_data->n_actions; i++) {
972 struct action_data *data = hist_data->actions[i];
973
974 if (data->handler == HANDLER_ONMATCH) {
975 char *system = data->match_data.event_system;
976 char *event_name = data->match_data.event;
977
978 file = find_var_file(tr, system, event_name, var_name);
979 if (!file)
980 continue;
981 hist_field = find_file_var(file, var_name);
982 if (hist_field) {
983 if (found) {
984 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE,
985 errpos(var_name));
986 return ERR_PTR(-EINVAL);
987 }
988
989 found = hist_field;
990 }
991 }
992 }
993 return found;
994 }
995
find_event_var(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)996 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
997 char *system,
998 char *event_name,
999 char *var_name)
1000 {
1001 struct trace_array *tr = hist_data->event_file->tr;
1002 struct hist_field *hist_field = NULL;
1003 struct trace_event_file *file;
1004
1005 if (!system || !event_name) {
1006 hist_field = find_match_var(hist_data, var_name);
1007 if (IS_ERR(hist_field))
1008 return NULL;
1009 if (hist_field)
1010 return hist_field;
1011 }
1012
1013 file = find_var_file(tr, system, event_name, var_name);
1014 if (!file)
1015 return NULL;
1016
1017 hist_field = find_file_var(file, var_name);
1018
1019 return hist_field;
1020 }
1021
hist_field_var_ref(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)1022 static u64 hist_field_var_ref(struct hist_field *hist_field,
1023 struct tracing_map_elt *elt,
1024 struct ring_buffer_event *rbe,
1025 void *event)
1026 {
1027 struct hist_elt_data *elt_data;
1028 u64 var_val = 0;
1029
1030 if (WARN_ON_ONCE(!elt))
1031 return var_val;
1032
1033 elt_data = elt->private_data;
1034 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1035
1036 return var_val;
1037 }
1038
resolve_var_refs(struct hist_trigger_data * hist_data,void * key,u64 * var_ref_vals,bool self)1039 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1040 u64 *var_ref_vals, bool self)
1041 {
1042 struct hist_trigger_data *var_data;
1043 struct tracing_map_elt *var_elt;
1044 struct hist_field *hist_field;
1045 unsigned int i, var_idx;
1046 bool resolved = true;
1047 u64 var_val = 0;
1048
1049 for (i = 0; i < hist_data->n_var_refs; i++) {
1050 hist_field = hist_data->var_refs[i];
1051 var_idx = hist_field->var.idx;
1052 var_data = hist_field->var.hist_data;
1053
1054 if (var_data == NULL) {
1055 resolved = false;
1056 break;
1057 }
1058
1059 if ((self && var_data != hist_data) ||
1060 (!self && var_data == hist_data))
1061 continue;
1062
1063 var_elt = tracing_map_lookup(var_data->map, key);
1064 if (!var_elt) {
1065 resolved = false;
1066 break;
1067 }
1068
1069 if (!tracing_map_var_set(var_elt, var_idx)) {
1070 resolved = false;
1071 break;
1072 }
1073
1074 if (self || !hist_field->read_once)
1075 var_val = tracing_map_read_var(var_elt, var_idx);
1076 else
1077 var_val = tracing_map_read_var_once(var_elt, var_idx);
1078
1079 var_ref_vals[i] = var_val;
1080 }
1081
1082 return resolved;
1083 }
1084
hist_field_name(struct hist_field * field,unsigned int level)1085 static const char *hist_field_name(struct hist_field *field,
1086 unsigned int level)
1087 {
1088 const char *field_name = "";
1089
1090 if (level > 1)
1091 return field_name;
1092
1093 if (field->field)
1094 field_name = field->field->name;
1095 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1096 field->flags & HIST_FIELD_FL_ALIAS)
1097 field_name = hist_field_name(field->operands[0], ++level);
1098 else if (field->flags & HIST_FIELD_FL_CPU)
1099 field_name = "common_cpu";
1100 else if (field->flags & HIST_FIELD_FL_EXPR ||
1101 field->flags & HIST_FIELD_FL_VAR_REF) {
1102 if (field->system) {
1103 static char full_name[MAX_FILTER_STR_VAL];
1104
1105 strcat(full_name, field->system);
1106 strcat(full_name, ".");
1107 strcat(full_name, field->event_name);
1108 strcat(full_name, ".");
1109 strcat(full_name, field->name);
1110 field_name = full_name;
1111 } else
1112 field_name = field->name;
1113 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1114 field_name = "common_timestamp";
1115
1116 if (field_name == NULL)
1117 field_name = "";
1118
1119 return field_name;
1120 }
1121
select_value_fn(int field_size,int field_is_signed)1122 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
1123 {
1124 hist_field_fn_t fn = NULL;
1125
1126 switch (field_size) {
1127 case 8:
1128 if (field_is_signed)
1129 fn = hist_field_s64;
1130 else
1131 fn = hist_field_u64;
1132 break;
1133 case 4:
1134 if (field_is_signed)
1135 fn = hist_field_s32;
1136 else
1137 fn = hist_field_u32;
1138 break;
1139 case 2:
1140 if (field_is_signed)
1141 fn = hist_field_s16;
1142 else
1143 fn = hist_field_u16;
1144 break;
1145 case 1:
1146 if (field_is_signed)
1147 fn = hist_field_s8;
1148 else
1149 fn = hist_field_u8;
1150 break;
1151 }
1152
1153 return fn;
1154 }
1155
parse_map_size(char * str)1156 static int parse_map_size(char *str)
1157 {
1158 unsigned long size, map_bits;
1159 int ret;
1160
1161 ret = kstrtoul(str, 0, &size);
1162 if (ret)
1163 goto out;
1164
1165 map_bits = ilog2(roundup_pow_of_two(size));
1166 if (map_bits < TRACING_MAP_BITS_MIN ||
1167 map_bits > TRACING_MAP_BITS_MAX)
1168 ret = -EINVAL;
1169 else
1170 ret = map_bits;
1171 out:
1172 return ret;
1173 }
1174
destroy_hist_trigger_attrs(struct hist_trigger_attrs * attrs)1175 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1176 {
1177 unsigned int i;
1178
1179 if (!attrs)
1180 return;
1181
1182 for (i = 0; i < attrs->n_assignments; i++)
1183 kfree(attrs->assignment_str[i]);
1184
1185 for (i = 0; i < attrs->n_actions; i++)
1186 kfree(attrs->action_str[i]);
1187
1188 kfree(attrs->name);
1189 kfree(attrs->sort_key_str);
1190 kfree(attrs->keys_str);
1191 kfree(attrs->vals_str);
1192 kfree(attrs->clock);
1193 kfree(attrs);
1194 }
1195
parse_action(char * str,struct hist_trigger_attrs * attrs)1196 static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1197 {
1198 int ret = -EINVAL;
1199
1200 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1201 return ret;
1202
1203 if ((str_has_prefix(str, "onmatch(")) ||
1204 (str_has_prefix(str, "onmax(")) ||
1205 (str_has_prefix(str, "onchange("))) {
1206 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
1207 if (!attrs->action_str[attrs->n_actions]) {
1208 ret = -ENOMEM;
1209 return ret;
1210 }
1211 attrs->n_actions++;
1212 ret = 0;
1213 }
1214 return ret;
1215 }
1216
parse_assignment(struct trace_array * tr,char * str,struct hist_trigger_attrs * attrs)1217 static int parse_assignment(struct trace_array *tr,
1218 char *str, struct hist_trigger_attrs *attrs)
1219 {
1220 int len, ret = 0;
1221
1222 if ((len = str_has_prefix(str, "key=")) ||
1223 (len = str_has_prefix(str, "keys="))) {
1224 attrs->keys_str = kstrdup(str + len, GFP_KERNEL);
1225 if (!attrs->keys_str) {
1226 ret = -ENOMEM;
1227 goto out;
1228 }
1229 } else if ((len = str_has_prefix(str, "val=")) ||
1230 (len = str_has_prefix(str, "vals=")) ||
1231 (len = str_has_prefix(str, "values="))) {
1232 attrs->vals_str = kstrdup(str + len, GFP_KERNEL);
1233 if (!attrs->vals_str) {
1234 ret = -ENOMEM;
1235 goto out;
1236 }
1237 } else if ((len = str_has_prefix(str, "sort="))) {
1238 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL);
1239 if (!attrs->sort_key_str) {
1240 ret = -ENOMEM;
1241 goto out;
1242 }
1243 } else if (str_has_prefix(str, "name=")) {
1244 attrs->name = kstrdup(str, GFP_KERNEL);
1245 if (!attrs->name) {
1246 ret = -ENOMEM;
1247 goto out;
1248 }
1249 } else if ((len = str_has_prefix(str, "clock="))) {
1250 str += len;
1251
1252 str = strstrip(str);
1253 attrs->clock = kstrdup(str, GFP_KERNEL);
1254 if (!attrs->clock) {
1255 ret = -ENOMEM;
1256 goto out;
1257 }
1258 } else if ((len = str_has_prefix(str, "size="))) {
1259 int map_bits = parse_map_size(str + len);
1260
1261 if (map_bits < 0) {
1262 ret = map_bits;
1263 goto out;
1264 }
1265 attrs->map_bits = map_bits;
1266 } else {
1267 char *assignment;
1268
1269 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1270 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str));
1271 ret = -EINVAL;
1272 goto out;
1273 }
1274
1275 assignment = kstrdup(str, GFP_KERNEL);
1276 if (!assignment) {
1277 ret = -ENOMEM;
1278 goto out;
1279 }
1280
1281 attrs->assignment_str[attrs->n_assignments++] = assignment;
1282 }
1283 out:
1284 return ret;
1285 }
1286
1287 static struct hist_trigger_attrs *
parse_hist_trigger_attrs(struct trace_array * tr,char * trigger_str)1288 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
1289 {
1290 struct hist_trigger_attrs *attrs;
1291 int ret = 0;
1292
1293 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
1294 if (!attrs)
1295 return ERR_PTR(-ENOMEM);
1296
1297 while (trigger_str) {
1298 char *str = strsep(&trigger_str, ":");
1299 char *rhs;
1300
1301 rhs = strchr(str, '=');
1302 if (rhs) {
1303 if (!strlen(++rhs)) {
1304 ret = -EINVAL;
1305 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str));
1306 goto free;
1307 }
1308 ret = parse_assignment(tr, str, attrs);
1309 if (ret)
1310 goto free;
1311 } else if (strcmp(str, "pause") == 0)
1312 attrs->pause = true;
1313 else if ((strcmp(str, "cont") == 0) ||
1314 (strcmp(str, "continue") == 0))
1315 attrs->cont = true;
1316 else if (strcmp(str, "clear") == 0)
1317 attrs->clear = true;
1318 else {
1319 ret = parse_action(str, attrs);
1320 if (ret)
1321 goto free;
1322 }
1323 }
1324
1325 if (!attrs->keys_str) {
1326 ret = -EINVAL;
1327 goto free;
1328 }
1329
1330 if (!attrs->clock) {
1331 attrs->clock = kstrdup("global", GFP_KERNEL);
1332 if (!attrs->clock) {
1333 ret = -ENOMEM;
1334 goto free;
1335 }
1336 }
1337
1338 return attrs;
1339 free:
1340 destroy_hist_trigger_attrs(attrs);
1341
1342 return ERR_PTR(ret);
1343 }
1344
save_comm(char * comm,struct task_struct * task)1345 static inline void save_comm(char *comm, struct task_struct *task)
1346 {
1347 if (!task->pid) {
1348 strcpy(comm, "<idle>");
1349 return;
1350 }
1351
1352 if (WARN_ON_ONCE(task->pid < 0)) {
1353 strcpy(comm, "<XXX>");
1354 return;
1355 }
1356
1357 strncpy(comm, task->comm, TASK_COMM_LEN);
1358 }
1359
hist_elt_data_free(struct hist_elt_data * elt_data)1360 static void hist_elt_data_free(struct hist_elt_data *elt_data)
1361 {
1362 unsigned int i;
1363
1364 for (i = 0; i < SYNTH_FIELDS_MAX; i++)
1365 kfree(elt_data->field_var_str[i]);
1366
1367 kfree(elt_data->comm);
1368 kfree(elt_data);
1369 }
1370
hist_trigger_elt_data_free(struct tracing_map_elt * elt)1371 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1372 {
1373 struct hist_elt_data *elt_data = elt->private_data;
1374
1375 hist_elt_data_free(elt_data);
1376 }
1377
hist_trigger_elt_data_alloc(struct tracing_map_elt * elt)1378 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1379 {
1380 struct hist_trigger_data *hist_data = elt->map->private_data;
1381 unsigned int size = TASK_COMM_LEN;
1382 struct hist_elt_data *elt_data;
1383 struct hist_field *key_field;
1384 unsigned int i, n_str;
1385
1386 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
1387 if (!elt_data)
1388 return -ENOMEM;
1389
1390 for_each_hist_key_field(i, hist_data) {
1391 key_field = hist_data->fields[i];
1392
1393 if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
1394 elt_data->comm = kzalloc(size, GFP_KERNEL);
1395 if (!elt_data->comm) {
1396 kfree(elt_data);
1397 return -ENOMEM;
1398 }
1399 break;
1400 }
1401 }
1402
1403 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str +
1404 hist_data->n_var_str;
1405 if (n_str > SYNTH_FIELDS_MAX) {
1406 hist_elt_data_free(elt_data);
1407 return -EINVAL;
1408 }
1409
1410 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1));
1411
1412 size = STR_VAR_LEN_MAX;
1413
1414 for (i = 0; i < n_str; i++) {
1415 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
1416 if (!elt_data->field_var_str[i]) {
1417 hist_elt_data_free(elt_data);
1418 return -ENOMEM;
1419 }
1420 }
1421
1422 elt->private_data = elt_data;
1423
1424 return 0;
1425 }
1426
hist_trigger_elt_data_init(struct tracing_map_elt * elt)1427 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
1428 {
1429 struct hist_elt_data *elt_data = elt->private_data;
1430
1431 if (elt_data->comm)
1432 save_comm(elt_data->comm, current);
1433 }
1434
1435 static const struct tracing_map_ops hist_trigger_elt_data_ops = {
1436 .elt_alloc = hist_trigger_elt_data_alloc,
1437 .elt_free = hist_trigger_elt_data_free,
1438 .elt_init = hist_trigger_elt_data_init,
1439 };
1440
get_hist_field_flags(struct hist_field * hist_field)1441 static const char *get_hist_field_flags(struct hist_field *hist_field)
1442 {
1443 const char *flags_str = NULL;
1444
1445 if (hist_field->flags & HIST_FIELD_FL_HEX)
1446 flags_str = "hex";
1447 else if (hist_field->flags & HIST_FIELD_FL_SYM)
1448 flags_str = "sym";
1449 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
1450 flags_str = "sym-offset";
1451 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
1452 flags_str = "execname";
1453 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
1454 flags_str = "syscall";
1455 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
1456 flags_str = "log2";
1457 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1458 flags_str = "usecs";
1459
1460 return flags_str;
1461 }
1462
expr_field_str(struct hist_field * field,char * expr)1463 static void expr_field_str(struct hist_field *field, char *expr)
1464 {
1465 if (field->flags & HIST_FIELD_FL_VAR_REF)
1466 strcat(expr, "$");
1467
1468 strcat(expr, hist_field_name(field, 0));
1469
1470 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
1471 const char *flags_str = get_hist_field_flags(field);
1472
1473 if (flags_str) {
1474 strcat(expr, ".");
1475 strcat(expr, flags_str);
1476 }
1477 }
1478 }
1479
expr_str(struct hist_field * field,unsigned int level)1480 static char *expr_str(struct hist_field *field, unsigned int level)
1481 {
1482 char *expr;
1483
1484 if (level > 1)
1485 return NULL;
1486
1487 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
1488 if (!expr)
1489 return NULL;
1490
1491 if (!field->operands[0]) {
1492 expr_field_str(field, expr);
1493 return expr;
1494 }
1495
1496 if (field->operator == FIELD_OP_UNARY_MINUS) {
1497 char *subexpr;
1498
1499 strcat(expr, "-(");
1500 subexpr = expr_str(field->operands[0], ++level);
1501 if (!subexpr) {
1502 kfree(expr);
1503 return NULL;
1504 }
1505 strcat(expr, subexpr);
1506 strcat(expr, ")");
1507
1508 kfree(subexpr);
1509
1510 return expr;
1511 }
1512
1513 expr_field_str(field->operands[0], expr);
1514
1515 switch (field->operator) {
1516 case FIELD_OP_MINUS:
1517 strcat(expr, "-");
1518 break;
1519 case FIELD_OP_PLUS:
1520 strcat(expr, "+");
1521 break;
1522 default:
1523 kfree(expr);
1524 return NULL;
1525 }
1526
1527 expr_field_str(field->operands[1], expr);
1528
1529 return expr;
1530 }
1531
contains_operator(char * str)1532 static int contains_operator(char *str)
1533 {
1534 enum field_op_id field_op = FIELD_OP_NONE;
1535 char *op;
1536
1537 op = strpbrk(str, "+-");
1538 if (!op)
1539 return FIELD_OP_NONE;
1540
1541 switch (*op) {
1542 case '-':
1543 /*
1544 * Unfortunately, the modifier ".sym-offset"
1545 * can confuse things.
1546 */
1547 if (op - str >= 4 && !strncmp(op - 4, ".sym-offset", 11))
1548 return FIELD_OP_NONE;
1549
1550 if (*str == '-')
1551 field_op = FIELD_OP_UNARY_MINUS;
1552 else
1553 field_op = FIELD_OP_MINUS;
1554 break;
1555 case '+':
1556 field_op = FIELD_OP_PLUS;
1557 break;
1558 default:
1559 break;
1560 }
1561
1562 return field_op;
1563 }
1564
get_hist_field(struct hist_field * hist_field)1565 static void get_hist_field(struct hist_field *hist_field)
1566 {
1567 hist_field->ref++;
1568 }
1569
__destroy_hist_field(struct hist_field * hist_field)1570 static void __destroy_hist_field(struct hist_field *hist_field)
1571 {
1572 if (--hist_field->ref > 1)
1573 return;
1574
1575 kfree(hist_field->var.name);
1576 kfree(hist_field->name);
1577 kfree(hist_field->type);
1578
1579 kfree(hist_field->system);
1580 kfree(hist_field->event_name);
1581
1582 kfree(hist_field);
1583 }
1584
destroy_hist_field(struct hist_field * hist_field,unsigned int level)1585 static void destroy_hist_field(struct hist_field *hist_field,
1586 unsigned int level)
1587 {
1588 unsigned int i;
1589
1590 if (level > 3)
1591 return;
1592
1593 if (!hist_field)
1594 return;
1595
1596 if (hist_field->flags & HIST_FIELD_FL_VAR_REF)
1597 return; /* var refs will be destroyed separately */
1598
1599 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
1600 destroy_hist_field(hist_field->operands[i], level + 1);
1601
1602 __destroy_hist_field(hist_field);
1603 }
1604
create_hist_field(struct hist_trigger_data * hist_data,struct ftrace_event_field * field,unsigned long flags,char * var_name)1605 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
1606 struct ftrace_event_field *field,
1607 unsigned long flags,
1608 char *var_name)
1609 {
1610 struct hist_field *hist_field;
1611
1612 if (field && is_function_field(field))
1613 return NULL;
1614
1615 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
1616 if (!hist_field)
1617 return NULL;
1618
1619 hist_field->ref = 1;
1620
1621 hist_field->hist_data = hist_data;
1622
1623 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
1624 goto out; /* caller will populate */
1625
1626 if (flags & HIST_FIELD_FL_VAR_REF) {
1627 hist_field->fn = hist_field_var_ref;
1628 goto out;
1629 }
1630
1631 if (flags & HIST_FIELD_FL_HITCOUNT) {
1632 hist_field->fn = hist_field_counter;
1633 hist_field->size = sizeof(u64);
1634 hist_field->type = kstrdup("u64", GFP_KERNEL);
1635 if (!hist_field->type)
1636 goto free;
1637 goto out;
1638 }
1639
1640 if (flags & HIST_FIELD_FL_STACKTRACE) {
1641 hist_field->fn = hist_field_none;
1642 goto out;
1643 }
1644
1645 if (flags & HIST_FIELD_FL_LOG2) {
1646 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
1647 hist_field->fn = hist_field_log2;
1648 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
1649 hist_field->size = hist_field->operands[0]->size;
1650 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
1651 if (!hist_field->type)
1652 goto free;
1653 goto out;
1654 }
1655
1656 if (flags & HIST_FIELD_FL_TIMESTAMP) {
1657 hist_field->fn = hist_field_timestamp;
1658 hist_field->size = sizeof(u64);
1659 hist_field->type = kstrdup("u64", GFP_KERNEL);
1660 if (!hist_field->type)
1661 goto free;
1662 goto out;
1663 }
1664
1665 if (flags & HIST_FIELD_FL_CPU) {
1666 hist_field->fn = hist_field_cpu;
1667 hist_field->size = sizeof(int);
1668 hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
1669 if (!hist_field->type)
1670 goto free;
1671 goto out;
1672 }
1673
1674 if (WARN_ON_ONCE(!field))
1675 goto out;
1676
1677 /* Pointers to strings are just pointers and dangerous to dereference */
1678 if (is_string_field(field) &&
1679 (field->filter_type != FILTER_PTR_STRING)) {
1680 flags |= HIST_FIELD_FL_STRING;
1681
1682 hist_field->size = MAX_FILTER_STR_VAL;
1683 hist_field->type = kstrdup(field->type, GFP_KERNEL);
1684 if (!hist_field->type)
1685 goto free;
1686
1687 if (field->filter_type == FILTER_STATIC_STRING) {
1688 hist_field->fn = hist_field_string;
1689 hist_field->size = field->size;
1690 } else if (field->filter_type == FILTER_DYN_STRING)
1691 hist_field->fn = hist_field_dynstring;
1692 else
1693 hist_field->fn = hist_field_pstring;
1694 } else {
1695 hist_field->size = field->size;
1696 hist_field->is_signed = field->is_signed;
1697 hist_field->type = kstrdup(field->type, GFP_KERNEL);
1698 if (!hist_field->type)
1699 goto free;
1700
1701 hist_field->fn = select_value_fn(field->size,
1702 field->is_signed);
1703 if (!hist_field->fn) {
1704 destroy_hist_field(hist_field, 0);
1705 return NULL;
1706 }
1707 }
1708 out:
1709 hist_field->field = field;
1710 hist_field->flags = flags;
1711
1712 if (var_name) {
1713 hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
1714 if (!hist_field->var.name)
1715 goto free;
1716 }
1717
1718 return hist_field;
1719 free:
1720 destroy_hist_field(hist_field, 0);
1721 return NULL;
1722 }
1723
destroy_hist_fields(struct hist_trigger_data * hist_data)1724 static void destroy_hist_fields(struct hist_trigger_data *hist_data)
1725 {
1726 unsigned int i;
1727
1728 for (i = 0; i < HIST_FIELDS_MAX; i++) {
1729 if (hist_data->fields[i]) {
1730 destroy_hist_field(hist_data->fields[i], 0);
1731 hist_data->fields[i] = NULL;
1732 }
1733 }
1734
1735 for (i = 0; i < hist_data->n_var_refs; i++) {
1736 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF));
1737 __destroy_hist_field(hist_data->var_refs[i]);
1738 hist_data->var_refs[i] = NULL;
1739 }
1740 }
1741
init_var_ref(struct hist_field * ref_field,struct hist_field * var_field,char * system,char * event_name)1742 static int init_var_ref(struct hist_field *ref_field,
1743 struct hist_field *var_field,
1744 char *system, char *event_name)
1745 {
1746 int err = 0;
1747
1748 ref_field->var.idx = var_field->var.idx;
1749 ref_field->var.hist_data = var_field->hist_data;
1750 ref_field->size = var_field->size;
1751 ref_field->is_signed = var_field->is_signed;
1752 ref_field->flags |= var_field->flags &
1753 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
1754
1755 if (system) {
1756 ref_field->system = kstrdup(system, GFP_KERNEL);
1757 if (!ref_field->system)
1758 return -ENOMEM;
1759 }
1760
1761 if (event_name) {
1762 ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
1763 if (!ref_field->event_name) {
1764 err = -ENOMEM;
1765 goto free;
1766 }
1767 }
1768
1769 if (var_field->var.name) {
1770 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
1771 if (!ref_field->name) {
1772 err = -ENOMEM;
1773 goto free;
1774 }
1775 } else if (var_field->name) {
1776 ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
1777 if (!ref_field->name) {
1778 err = -ENOMEM;
1779 goto free;
1780 }
1781 }
1782
1783 ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
1784 if (!ref_field->type) {
1785 err = -ENOMEM;
1786 goto free;
1787 }
1788 out:
1789 return err;
1790 free:
1791 kfree(ref_field->system);
1792 kfree(ref_field->event_name);
1793 kfree(ref_field->name);
1794
1795 goto out;
1796 }
1797
find_var_ref_idx(struct hist_trigger_data * hist_data,struct hist_field * var_field)1798 static int find_var_ref_idx(struct hist_trigger_data *hist_data,
1799 struct hist_field *var_field)
1800 {
1801 struct hist_field *ref_field;
1802 int i;
1803
1804 for (i = 0; i < hist_data->n_var_refs; i++) {
1805 ref_field = hist_data->var_refs[i];
1806 if (ref_field->var.idx == var_field->var.idx &&
1807 ref_field->var.hist_data == var_field->hist_data)
1808 return i;
1809 }
1810
1811 return -ENOENT;
1812 }
1813
1814 /**
1815 * create_var_ref - Create a variable reference and attach it to trigger
1816 * @hist_data: The trigger that will be referencing the variable
1817 * @var_field: The VAR field to create a reference to
1818 * @system: The optional system string
1819 * @event_name: The optional event_name string
1820 *
1821 * Given a variable hist_field, create a VAR_REF hist_field that
1822 * represents a reference to it.
1823 *
1824 * This function also adds the reference to the trigger that
1825 * now references the variable.
1826 *
1827 * Return: The VAR_REF field if successful, NULL if not
1828 */
create_var_ref(struct hist_trigger_data * hist_data,struct hist_field * var_field,char * system,char * event_name)1829 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
1830 struct hist_field *var_field,
1831 char *system, char *event_name)
1832 {
1833 unsigned long flags = HIST_FIELD_FL_VAR_REF;
1834 struct hist_field *ref_field;
1835 int i;
1836
1837 /* Check if the variable already exists */
1838 for (i = 0; i < hist_data->n_var_refs; i++) {
1839 ref_field = hist_data->var_refs[i];
1840 if (ref_field->var.idx == var_field->var.idx &&
1841 ref_field->var.hist_data == var_field->hist_data) {
1842 get_hist_field(ref_field);
1843 return ref_field;
1844 }
1845 }
1846
1847 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
1848 if (ref_field) {
1849 if (init_var_ref(ref_field, var_field, system, event_name)) {
1850 destroy_hist_field(ref_field, 0);
1851 return NULL;
1852 }
1853
1854 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
1855 ref_field->var_ref_idx = hist_data->n_var_refs++;
1856 }
1857
1858 return ref_field;
1859 }
1860
is_var_ref(char * var_name)1861 static bool is_var_ref(char *var_name)
1862 {
1863 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
1864 return false;
1865
1866 return true;
1867 }
1868
field_name_from_var(struct hist_trigger_data * hist_data,char * var_name)1869 static char *field_name_from_var(struct hist_trigger_data *hist_data,
1870 char *var_name)
1871 {
1872 char *name, *field;
1873 unsigned int i;
1874
1875 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
1876 name = hist_data->attrs->var_defs.name[i];
1877
1878 if (strcmp(var_name, name) == 0) {
1879 field = hist_data->attrs->var_defs.expr[i];
1880 if (contains_operator(field) || is_var_ref(field))
1881 continue;
1882 return field;
1883 }
1884 }
1885
1886 return NULL;
1887 }
1888
local_field_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)1889 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
1890 char *system, char *event_name,
1891 char *var_name)
1892 {
1893 struct trace_event_call *call;
1894
1895 if (system && event_name) {
1896 call = hist_data->event_file->event_call;
1897
1898 if (strcmp(system, call->class->system) != 0)
1899 return NULL;
1900
1901 if (strcmp(event_name, trace_event_name(call)) != 0)
1902 return NULL;
1903 }
1904
1905 if (!!system != !!event_name)
1906 return NULL;
1907
1908 if (!is_var_ref(var_name))
1909 return NULL;
1910
1911 var_name++;
1912
1913 return field_name_from_var(hist_data, var_name);
1914 }
1915
parse_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)1916 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
1917 char *system, char *event_name,
1918 char *var_name)
1919 {
1920 struct hist_field *var_field = NULL, *ref_field = NULL;
1921 struct trace_array *tr = hist_data->event_file->tr;
1922
1923 if (!is_var_ref(var_name))
1924 return NULL;
1925
1926 var_name++;
1927
1928 var_field = find_event_var(hist_data, system, event_name, var_name);
1929 if (var_field)
1930 ref_field = create_var_ref(hist_data, var_field,
1931 system, event_name);
1932
1933 if (!ref_field)
1934 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name));
1935
1936 return ref_field;
1937 }
1938
1939 static struct ftrace_event_field *
parse_field(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_str,unsigned long * flags)1940 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
1941 char *field_str, unsigned long *flags)
1942 {
1943 struct ftrace_event_field *field = NULL;
1944 char *field_name, *modifier, *str;
1945 struct trace_array *tr = file->tr;
1946
1947 modifier = str = kstrdup(field_str, GFP_KERNEL);
1948 if (!modifier)
1949 return ERR_PTR(-ENOMEM);
1950
1951 field_name = strsep(&modifier, ".");
1952 if (modifier) {
1953 if (strcmp(modifier, "hex") == 0)
1954 *flags |= HIST_FIELD_FL_HEX;
1955 else if (strcmp(modifier, "sym") == 0)
1956 *flags |= HIST_FIELD_FL_SYM;
1957 else if (strcmp(modifier, "sym-offset") == 0)
1958 *flags |= HIST_FIELD_FL_SYM_OFFSET;
1959 else if ((strcmp(modifier, "execname") == 0) &&
1960 (strcmp(field_name, "common_pid") == 0))
1961 *flags |= HIST_FIELD_FL_EXECNAME;
1962 else if (strcmp(modifier, "syscall") == 0)
1963 *flags |= HIST_FIELD_FL_SYSCALL;
1964 else if (strcmp(modifier, "log2") == 0)
1965 *flags |= HIST_FIELD_FL_LOG2;
1966 else if (strcmp(modifier, "usecs") == 0)
1967 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
1968 else {
1969 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
1970 field = ERR_PTR(-EINVAL);
1971 goto out;
1972 }
1973 }
1974
1975 if (strcmp(field_name, "common_timestamp") == 0) {
1976 *flags |= HIST_FIELD_FL_TIMESTAMP;
1977 hist_data->enable_timestamps = true;
1978 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1979 hist_data->attrs->ts_in_usecs = true;
1980 } else if (strcmp(field_name, "common_cpu") == 0)
1981 *flags |= HIST_FIELD_FL_CPU;
1982 else {
1983 field = trace_find_event_field(file->event_call, field_name);
1984 if (!field || !field->size) {
1985 /*
1986 * For backward compatibility, if field_name
1987 * was "cpu", then we treat this the same as
1988 * common_cpu.
1989 */
1990 if (strcmp(field_name, "cpu") == 0) {
1991 *flags |= HIST_FIELD_FL_CPU;
1992 } else {
1993 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND,
1994 errpos(field_name));
1995 field = ERR_PTR(-EINVAL);
1996 goto out;
1997 }
1998 }
1999 }
2000 out:
2001 kfree(str);
2002
2003 return field;
2004 }
2005
create_alias(struct hist_trigger_data * hist_data,struct hist_field * var_ref,char * var_name)2006 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2007 struct hist_field *var_ref,
2008 char *var_name)
2009 {
2010 struct hist_field *alias = NULL;
2011 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2012
2013 alias = create_hist_field(hist_data, NULL, flags, var_name);
2014 if (!alias)
2015 return NULL;
2016
2017 alias->fn = var_ref->fn;
2018 alias->operands[0] = var_ref;
2019
2020 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2021 destroy_hist_field(alias, 0);
2022 return NULL;
2023 }
2024
2025 alias->var_ref_idx = var_ref->var_ref_idx;
2026
2027 return alias;
2028 }
2029
parse_atom(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long * flags,char * var_name)2030 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2031 struct trace_event_file *file, char *str,
2032 unsigned long *flags, char *var_name)
2033 {
2034 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2035 struct ftrace_event_field *field = NULL;
2036 struct hist_field *hist_field = NULL;
2037 int ret = 0;
2038
2039 s = strchr(str, '.');
2040 if (s) {
2041 s = strchr(++s, '.');
2042 if (s) {
2043 ref_system = strsep(&str, ".");
2044 if (!str) {
2045 ret = -EINVAL;
2046 goto out;
2047 }
2048 ref_event = strsep(&str, ".");
2049 if (!str) {
2050 ret = -EINVAL;
2051 goto out;
2052 }
2053 ref_var = str;
2054 }
2055 }
2056
2057 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2058 if (!s) {
2059 hist_field = parse_var_ref(hist_data, ref_system,
2060 ref_event, ref_var);
2061 if (hist_field) {
2062 if (var_name) {
2063 hist_field = create_alias(hist_data, hist_field, var_name);
2064 if (!hist_field) {
2065 ret = -ENOMEM;
2066 goto out;
2067 }
2068 }
2069 return hist_field;
2070 }
2071 } else
2072 str = s;
2073
2074 field = parse_field(hist_data, file, str, flags);
2075 if (IS_ERR(field)) {
2076 ret = PTR_ERR(field);
2077 goto out;
2078 }
2079
2080 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2081 if (!hist_field) {
2082 ret = -ENOMEM;
2083 goto out;
2084 }
2085
2086 return hist_field;
2087 out:
2088 return ERR_PTR(ret);
2089 }
2090
2091 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2092 struct trace_event_file *file,
2093 char *str, unsigned long flags,
2094 char *var_name, unsigned int level);
2095
parse_unary(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int level)2096 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2097 struct trace_event_file *file,
2098 char *str, unsigned long flags,
2099 char *var_name, unsigned int level)
2100 {
2101 struct hist_field *operand1, *expr = NULL;
2102 unsigned long operand_flags;
2103 int ret = 0;
2104 char *s;
2105
2106 /* we support only -(xxx) i.e. explicit parens required */
2107
2108 if (level > 3) {
2109 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2110 ret = -EINVAL;
2111 goto free;
2112 }
2113
2114 str++; /* skip leading '-' */
2115
2116 s = strchr(str, '(');
2117 if (s)
2118 str++;
2119 else {
2120 ret = -EINVAL;
2121 goto free;
2122 }
2123
2124 s = strrchr(str, ')');
2125 if (s)
2126 *s = '\0';
2127 else {
2128 ret = -EINVAL; /* no closing ')' */
2129 goto free;
2130 }
2131
2132 flags |= HIST_FIELD_FL_EXPR;
2133 expr = create_hist_field(hist_data, NULL, flags, var_name);
2134 if (!expr) {
2135 ret = -ENOMEM;
2136 goto free;
2137 }
2138
2139 operand_flags = 0;
2140 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2141 if (IS_ERR(operand1)) {
2142 ret = PTR_ERR(operand1);
2143 goto free;
2144 }
2145 if (operand1->flags & HIST_FIELD_FL_STRING) {
2146 /* String type can not be the operand of unary operator. */
2147 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2148 destroy_hist_field(operand1, 0);
2149 ret = -EINVAL;
2150 goto free;
2151 }
2152
2153 expr->flags |= operand1->flags &
2154 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2155 expr->fn = hist_field_unary_minus;
2156 expr->operands[0] = operand1;
2157 expr->operator = FIELD_OP_UNARY_MINUS;
2158 expr->name = expr_str(expr, 0);
2159 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2160 if (!expr->type) {
2161 ret = -ENOMEM;
2162 goto free;
2163 }
2164
2165 return expr;
2166 free:
2167 destroy_hist_field(expr, 0);
2168 return ERR_PTR(ret);
2169 }
2170
check_expr_operands(struct trace_array * tr,struct hist_field * operand1,struct hist_field * operand2)2171 static int check_expr_operands(struct trace_array *tr,
2172 struct hist_field *operand1,
2173 struct hist_field *operand2)
2174 {
2175 unsigned long operand1_flags = operand1->flags;
2176 unsigned long operand2_flags = operand2->flags;
2177
2178 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2179 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2180 struct hist_field *var;
2181
2182 var = find_var_field(operand1->var.hist_data, operand1->name);
2183 if (!var)
2184 return -EINVAL;
2185 operand1_flags = var->flags;
2186 }
2187
2188 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2189 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2190 struct hist_field *var;
2191
2192 var = find_var_field(operand2->var.hist_data, operand2->name);
2193 if (!var)
2194 return -EINVAL;
2195 operand2_flags = var->flags;
2196 }
2197
2198 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2199 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2200 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0);
2201 return -EINVAL;
2202 }
2203
2204 return 0;
2205 }
2206
parse_expr(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int level)2207 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2208 struct trace_event_file *file,
2209 char *str, unsigned long flags,
2210 char *var_name, unsigned int level)
2211 {
2212 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2213 unsigned long operand_flags;
2214 int field_op, ret = -EINVAL;
2215 char *sep, *operand1_str;
2216
2217 if (level > 3) {
2218 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2219 return ERR_PTR(-EINVAL);
2220 }
2221
2222 field_op = contains_operator(str);
2223
2224 if (field_op == FIELD_OP_NONE)
2225 return parse_atom(hist_data, file, str, &flags, var_name);
2226
2227 if (field_op == FIELD_OP_UNARY_MINUS)
2228 return parse_unary(hist_data, file, str, flags, var_name, ++level);
2229
2230 switch (field_op) {
2231 case FIELD_OP_MINUS:
2232 sep = "-";
2233 break;
2234 case FIELD_OP_PLUS:
2235 sep = "+";
2236 break;
2237 default:
2238 goto free;
2239 }
2240
2241 operand1_str = strsep(&str, sep);
2242 if (!operand1_str || !str)
2243 goto free;
2244
2245 operand_flags = 0;
2246 operand1 = parse_atom(hist_data, file, operand1_str,
2247 &operand_flags, NULL);
2248 if (IS_ERR(operand1)) {
2249 ret = PTR_ERR(operand1);
2250 operand1 = NULL;
2251 goto free;
2252 }
2253 if (operand1->flags & HIST_FIELD_FL_STRING) {
2254 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str));
2255 ret = -EINVAL;
2256 goto free;
2257 }
2258
2259 /* rest of string could be another expression e.g. b+c in a+b+c */
2260 operand_flags = 0;
2261 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2262 if (IS_ERR(operand2)) {
2263 ret = PTR_ERR(operand2);
2264 operand2 = NULL;
2265 goto free;
2266 }
2267 if (operand2->flags & HIST_FIELD_FL_STRING) {
2268 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2269 ret = -EINVAL;
2270 goto free;
2271 }
2272
2273 ret = check_expr_operands(file->tr, operand1, operand2);
2274 if (ret)
2275 goto free;
2276
2277 flags |= HIST_FIELD_FL_EXPR;
2278
2279 flags |= operand1->flags &
2280 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2281
2282 expr = create_hist_field(hist_data, NULL, flags, var_name);
2283 if (!expr) {
2284 ret = -ENOMEM;
2285 goto free;
2286 }
2287
2288 operand1->read_once = true;
2289 operand2->read_once = true;
2290
2291 expr->operands[0] = operand1;
2292 expr->operands[1] = operand2;
2293
2294 /* The operand sizes should be the same, so just pick one */
2295 expr->size = operand1->size;
2296
2297 expr->operator = field_op;
2298 expr->name = expr_str(expr, 0);
2299 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2300 if (!expr->type) {
2301 ret = -ENOMEM;
2302 goto free;
2303 }
2304
2305 switch (field_op) {
2306 case FIELD_OP_MINUS:
2307 expr->fn = hist_field_minus;
2308 break;
2309 case FIELD_OP_PLUS:
2310 expr->fn = hist_field_plus;
2311 break;
2312 default:
2313 ret = -EINVAL;
2314 goto free;
2315 }
2316
2317 return expr;
2318 free:
2319 destroy_hist_field(operand1, 0);
2320 destroy_hist_field(operand2, 0);
2321 destroy_hist_field(expr, 0);
2322
2323 return ERR_PTR(ret);
2324 }
2325
find_trigger_filter(struct hist_trigger_data * hist_data,struct trace_event_file * file)2326 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2327 struct trace_event_file *file)
2328 {
2329 struct event_trigger_data *test;
2330
2331 lockdep_assert_held(&event_mutex);
2332
2333 list_for_each_entry(test, &file->triggers, list) {
2334 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2335 if (test->private_data == hist_data)
2336 return test->filter_str;
2337 }
2338 }
2339
2340 return NULL;
2341 }
2342
2343 static struct event_command trigger_hist_cmd;
2344 static int event_hist_trigger_func(struct event_command *cmd_ops,
2345 struct trace_event_file *file,
2346 char *glob, char *cmd, char *param);
2347
compatible_keys(struct hist_trigger_data * target_hist_data,struct hist_trigger_data * hist_data,unsigned int n_keys)2348 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2349 struct hist_trigger_data *hist_data,
2350 unsigned int n_keys)
2351 {
2352 struct hist_field *target_hist_field, *hist_field;
2353 unsigned int n, i, j;
2354
2355 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2356 return false;
2357
2358 i = hist_data->n_vals;
2359 j = target_hist_data->n_vals;
2360
2361 for (n = 0; n < n_keys; n++) {
2362 hist_field = hist_data->fields[i + n];
2363 target_hist_field = target_hist_data->fields[j + n];
2364
2365 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2366 return false;
2367 if (hist_field->size != target_hist_field->size)
2368 return false;
2369 if (hist_field->is_signed != target_hist_field->is_signed)
2370 return false;
2371 }
2372
2373 return true;
2374 }
2375
2376 static struct hist_trigger_data *
find_compatible_hist(struct hist_trigger_data * target_hist_data,struct trace_event_file * file)2377 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2378 struct trace_event_file *file)
2379 {
2380 struct hist_trigger_data *hist_data;
2381 struct event_trigger_data *test;
2382 unsigned int n_keys;
2383
2384 lockdep_assert_held(&event_mutex);
2385
2386 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2387
2388 list_for_each_entry(test, &file->triggers, list) {
2389 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2390 hist_data = test->private_data;
2391
2392 if (compatible_keys(target_hist_data, hist_data, n_keys))
2393 return hist_data;
2394 }
2395 }
2396
2397 return NULL;
2398 }
2399
event_file(struct trace_array * tr,char * system,char * event_name)2400 static struct trace_event_file *event_file(struct trace_array *tr,
2401 char *system, char *event_name)
2402 {
2403 struct trace_event_file *file;
2404
2405 file = __find_event_file(tr, system, event_name);
2406 if (!file)
2407 return ERR_PTR(-EINVAL);
2408
2409 return file;
2410 }
2411
2412 static struct hist_field *
find_synthetic_field_var(struct hist_trigger_data * target_hist_data,char * system,char * event_name,char * field_name)2413 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2414 char *system, char *event_name, char *field_name)
2415 {
2416 struct hist_field *event_var;
2417 char *synthetic_name;
2418
2419 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2420 if (!synthetic_name)
2421 return ERR_PTR(-ENOMEM);
2422
2423 strcpy(synthetic_name, "synthetic_");
2424 strcat(synthetic_name, field_name);
2425
2426 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2427
2428 kfree(synthetic_name);
2429
2430 return event_var;
2431 }
2432
2433 /**
2434 * create_field_var_hist - Automatically create a histogram and var for a field
2435 * @target_hist_data: The target hist trigger
2436 * @subsys_name: Optional subsystem name
2437 * @event_name: Optional event name
2438 * @field_name: The name of the field (and the resulting variable)
2439 *
2440 * Hist trigger actions fetch data from variables, not directly from
2441 * events. However, for convenience, users are allowed to directly
2442 * specify an event field in an action, which will be automatically
2443 * converted into a variable on their behalf.
2444
2445 * If a user specifies a field on an event that isn't the event the
2446 * histogram currently being defined (the target event histogram), the
2447 * only way that can be accomplished is if a new hist trigger is
2448 * created and the field variable defined on that.
2449 *
2450 * This function creates a new histogram compatible with the target
2451 * event (meaning a histogram with the same key as the target
2452 * histogram), and creates a variable for the specified field, but
2453 * with 'synthetic_' prepended to the variable name in order to avoid
2454 * collision with normal field variables.
2455 *
2456 * Return: The variable created for the field.
2457 */
2458 static struct hist_field *
create_field_var_hist(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * field_name)2459 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2460 char *subsys_name, char *event_name, char *field_name)
2461 {
2462 struct trace_array *tr = target_hist_data->event_file->tr;
2463 struct hist_field *event_var = ERR_PTR(-EINVAL);
2464 struct hist_trigger_data *hist_data;
2465 unsigned int i, n, first = true;
2466 struct field_var_hist *var_hist;
2467 struct trace_event_file *file;
2468 struct hist_field *key_field;
2469 char *saved_filter;
2470 char *cmd;
2471 int ret;
2472
2473 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2474 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2475 return ERR_PTR(-EINVAL);
2476 }
2477
2478 file = event_file(tr, subsys_name, event_name);
2479
2480 if (IS_ERR(file)) {
2481 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name));
2482 ret = PTR_ERR(file);
2483 return ERR_PTR(ret);
2484 }
2485
2486 /*
2487 * Look for a histogram compatible with target. We'll use the
2488 * found histogram specification to create a new matching
2489 * histogram with our variable on it. target_hist_data is not
2490 * yet a registered histogram so we can't use that.
2491 */
2492 hist_data = find_compatible_hist(target_hist_data, file);
2493 if (!hist_data) {
2494 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name));
2495 return ERR_PTR(-EINVAL);
2496 }
2497
2498 /* See if a synthetic field variable has already been created */
2499 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2500 event_name, field_name);
2501 if (!IS_ERR_OR_NULL(event_var))
2502 return event_var;
2503
2504 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2505 if (!var_hist)
2506 return ERR_PTR(-ENOMEM);
2507
2508 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2509 if (!cmd) {
2510 kfree(var_hist);
2511 return ERR_PTR(-ENOMEM);
2512 }
2513
2514 /* Use the same keys as the compatible histogram */
2515 strcat(cmd, "keys=");
2516
2517 for_each_hist_key_field(i, hist_data) {
2518 key_field = hist_data->fields[i];
2519 if (!first)
2520 strcat(cmd, ",");
2521 strcat(cmd, key_field->field->name);
2522 first = false;
2523 }
2524
2525 /* Create the synthetic field variable specification */
2526 strcat(cmd, ":synthetic_");
2527 strcat(cmd, field_name);
2528 strcat(cmd, "=");
2529 strcat(cmd, field_name);
2530
2531 /* Use the same filter as the compatible histogram */
2532 saved_filter = find_trigger_filter(hist_data, file);
2533 if (saved_filter) {
2534 strcat(cmd, " if ");
2535 strcat(cmd, saved_filter);
2536 }
2537
2538 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
2539 if (!var_hist->cmd) {
2540 kfree(cmd);
2541 kfree(var_hist);
2542 return ERR_PTR(-ENOMEM);
2543 }
2544
2545 /* Save the compatible histogram information */
2546 var_hist->hist_data = hist_data;
2547
2548 /* Create the new histogram with our variable */
2549 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
2550 "", "hist", cmd);
2551 if (ret) {
2552 kfree(cmd);
2553 kfree(var_hist->cmd);
2554 kfree(var_hist);
2555 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name));
2556 return ERR_PTR(ret);
2557 }
2558
2559 kfree(cmd);
2560
2561 /* If we can't find the variable, something went wrong */
2562 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2563 event_name, field_name);
2564 if (IS_ERR_OR_NULL(event_var)) {
2565 kfree(var_hist->cmd);
2566 kfree(var_hist);
2567 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name));
2568 return ERR_PTR(-EINVAL);
2569 }
2570
2571 n = target_hist_data->n_field_var_hists;
2572 target_hist_data->field_var_hists[n] = var_hist;
2573 target_hist_data->n_field_var_hists++;
2574
2575 return event_var;
2576 }
2577
2578 static struct hist_field *
find_target_event_var(struct hist_trigger_data * hist_data,char * subsys_name,char * event_name,char * var_name)2579 find_target_event_var(struct hist_trigger_data *hist_data,
2580 char *subsys_name, char *event_name, char *var_name)
2581 {
2582 struct trace_event_file *file = hist_data->event_file;
2583 struct hist_field *hist_field = NULL;
2584
2585 if (subsys_name) {
2586 struct trace_event_call *call;
2587
2588 if (!event_name)
2589 return NULL;
2590
2591 call = file->event_call;
2592
2593 if (strcmp(subsys_name, call->class->system) != 0)
2594 return NULL;
2595
2596 if (strcmp(event_name, trace_event_name(call)) != 0)
2597 return NULL;
2598 }
2599
2600 hist_field = find_var_field(hist_data, var_name);
2601
2602 return hist_field;
2603 }
2604
__update_field_vars(struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * rec,struct field_var ** field_vars,unsigned int n_field_vars,unsigned int field_var_str_start)2605 static inline void __update_field_vars(struct tracing_map_elt *elt,
2606 struct ring_buffer_event *rbe,
2607 void *rec,
2608 struct field_var **field_vars,
2609 unsigned int n_field_vars,
2610 unsigned int field_var_str_start)
2611 {
2612 struct hist_elt_data *elt_data = elt->private_data;
2613 unsigned int i, j, var_idx;
2614 u64 var_val;
2615
2616 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
2617 struct field_var *field_var = field_vars[i];
2618 struct hist_field *var = field_var->var;
2619 struct hist_field *val = field_var->val;
2620
2621 var_val = val->fn(val, elt, rbe, rec);
2622 var_idx = var->var.idx;
2623
2624 if (val->flags & HIST_FIELD_FL_STRING) {
2625 char *str = elt_data->field_var_str[j++];
2626 char *val_str = (char *)(uintptr_t)var_val;
2627 unsigned int size;
2628
2629 size = min(val->size, STR_VAR_LEN_MAX);
2630 strscpy(str, val_str, size);
2631 var_val = (u64)(uintptr_t)str;
2632 }
2633 tracing_map_set_var(elt, var_idx, var_val);
2634 }
2635 }
2636
update_field_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * rec)2637 static void update_field_vars(struct hist_trigger_data *hist_data,
2638 struct tracing_map_elt *elt,
2639 struct ring_buffer_event *rbe,
2640 void *rec)
2641 {
2642 __update_field_vars(elt, rbe, rec, hist_data->field_vars,
2643 hist_data->n_field_vars, 0);
2644 }
2645
save_track_data_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)2646 static void save_track_data_vars(struct hist_trigger_data *hist_data,
2647 struct tracing_map_elt *elt, void *rec,
2648 struct ring_buffer_event *rbe, void *key,
2649 struct action_data *data, u64 *var_ref_vals)
2650 {
2651 __update_field_vars(elt, rbe, rec, hist_data->save_vars,
2652 hist_data->n_save_vars, hist_data->n_field_var_str);
2653 }
2654
create_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * name,int size,const char * type)2655 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
2656 struct trace_event_file *file,
2657 char *name, int size, const char *type)
2658 {
2659 struct hist_field *var;
2660 int idx;
2661
2662 if (find_var(hist_data, file, name) && !hist_data->remove) {
2663 var = ERR_PTR(-EINVAL);
2664 goto out;
2665 }
2666
2667 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
2668 if (!var) {
2669 var = ERR_PTR(-ENOMEM);
2670 goto out;
2671 }
2672
2673 idx = tracing_map_add_var(hist_data->map);
2674 if (idx < 0) {
2675 kfree(var);
2676 var = ERR_PTR(-EINVAL);
2677 goto out;
2678 }
2679
2680 var->ref = 1;
2681 var->flags = HIST_FIELD_FL_VAR;
2682 var->var.idx = idx;
2683 var->var.hist_data = var->hist_data = hist_data;
2684 var->size = size;
2685 var->var.name = kstrdup(name, GFP_KERNEL);
2686 var->type = kstrdup(type, GFP_KERNEL);
2687 if (!var->var.name || !var->type) {
2688 kfree(var->var.name);
2689 kfree(var->type);
2690 kfree(var);
2691 var = ERR_PTR(-ENOMEM);
2692 }
2693 out:
2694 return var;
2695 }
2696
create_field_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_name)2697 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
2698 struct trace_event_file *file,
2699 char *field_name)
2700 {
2701 struct hist_field *val = NULL, *var = NULL;
2702 unsigned long flags = HIST_FIELD_FL_VAR;
2703 struct trace_array *tr = file->tr;
2704 struct field_var *field_var;
2705 int ret = 0;
2706
2707 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
2708 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2709 ret = -EINVAL;
2710 goto err;
2711 }
2712
2713 val = parse_atom(hist_data, file, field_name, &flags, NULL);
2714 if (IS_ERR(val)) {
2715 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name));
2716 ret = PTR_ERR(val);
2717 goto err;
2718 }
2719
2720 var = create_var(hist_data, file, field_name, val->size, val->type);
2721 if (IS_ERR(var)) {
2722 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name));
2723 kfree(val);
2724 ret = PTR_ERR(var);
2725 goto err;
2726 }
2727
2728 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
2729 if (!field_var) {
2730 kfree(val);
2731 kfree(var);
2732 ret = -ENOMEM;
2733 goto err;
2734 }
2735
2736 field_var->var = var;
2737 field_var->val = val;
2738 out:
2739 return field_var;
2740 err:
2741 field_var = ERR_PTR(ret);
2742 goto out;
2743 }
2744
2745 /**
2746 * create_target_field_var - Automatically create a variable for a field
2747 * @target_hist_data: The target hist trigger
2748 * @subsys_name: Optional subsystem name
2749 * @event_name: Optional event name
2750 * @var_name: The name of the field (and the resulting variable)
2751 *
2752 * Hist trigger actions fetch data from variables, not directly from
2753 * events. However, for convenience, users are allowed to directly
2754 * specify an event field in an action, which will be automatically
2755 * converted into a variable on their behalf.
2756
2757 * This function creates a field variable with the name var_name on
2758 * the hist trigger currently being defined on the target event. If
2759 * subsys_name and event_name are specified, this function simply
2760 * verifies that they do in fact match the target event subsystem and
2761 * event name.
2762 *
2763 * Return: The variable created for the field.
2764 */
2765 static struct field_var *
create_target_field_var(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * var_name)2766 create_target_field_var(struct hist_trigger_data *target_hist_data,
2767 char *subsys_name, char *event_name, char *var_name)
2768 {
2769 struct trace_event_file *file = target_hist_data->event_file;
2770
2771 if (subsys_name) {
2772 struct trace_event_call *call;
2773
2774 if (!event_name)
2775 return NULL;
2776
2777 call = file->event_call;
2778
2779 if (strcmp(subsys_name, call->class->system) != 0)
2780 return NULL;
2781
2782 if (strcmp(event_name, trace_event_name(call)) != 0)
2783 return NULL;
2784 }
2785
2786 return create_field_var(target_hist_data, file, var_name);
2787 }
2788
check_track_val_max(u64 track_val,u64 var_val)2789 static bool check_track_val_max(u64 track_val, u64 var_val)
2790 {
2791 if (var_val <= track_val)
2792 return false;
2793
2794 return true;
2795 }
2796
check_track_val_changed(u64 track_val,u64 var_val)2797 static bool check_track_val_changed(u64 track_val, u64 var_val)
2798 {
2799 if (var_val == track_val)
2800 return false;
2801
2802 return true;
2803 }
2804
get_track_val(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)2805 static u64 get_track_val(struct hist_trigger_data *hist_data,
2806 struct tracing_map_elt *elt,
2807 struct action_data *data)
2808 {
2809 unsigned int track_var_idx = data->track_data.track_var->var.idx;
2810 u64 track_val;
2811
2812 track_val = tracing_map_read_var(elt, track_var_idx);
2813
2814 return track_val;
2815 }
2816
save_track_val(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data,u64 var_val)2817 static void save_track_val(struct hist_trigger_data *hist_data,
2818 struct tracing_map_elt *elt,
2819 struct action_data *data, u64 var_val)
2820 {
2821 unsigned int track_var_idx = data->track_data.track_var->var.idx;
2822
2823 tracing_map_set_var(elt, track_var_idx, var_val);
2824 }
2825
save_track_data(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)2826 static void save_track_data(struct hist_trigger_data *hist_data,
2827 struct tracing_map_elt *elt, void *rec,
2828 struct ring_buffer_event *rbe, void *key,
2829 struct action_data *data, u64 *var_ref_vals)
2830 {
2831 if (data->track_data.save_data)
2832 data->track_data.save_data(hist_data, elt, rec, rbe, key, data, var_ref_vals);
2833 }
2834
check_track_val(struct tracing_map_elt * elt,struct action_data * data,u64 var_val)2835 static bool check_track_val(struct tracing_map_elt *elt,
2836 struct action_data *data,
2837 u64 var_val)
2838 {
2839 struct hist_trigger_data *hist_data;
2840 u64 track_val;
2841
2842 hist_data = data->track_data.track_var->hist_data;
2843 track_val = get_track_val(hist_data, elt, data);
2844
2845 return data->track_data.check_val(track_val, var_val);
2846 }
2847
2848 #ifdef CONFIG_TRACER_SNAPSHOT
cond_snapshot_update(struct trace_array * tr,void * cond_data)2849 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
2850 {
2851 /* called with tr->max_lock held */
2852 struct track_data *track_data = tr->cond_snapshot->cond_data;
2853 struct hist_elt_data *elt_data, *track_elt_data;
2854 struct snapshot_context *context = cond_data;
2855 struct action_data *action;
2856 u64 track_val;
2857
2858 if (!track_data)
2859 return false;
2860
2861 action = track_data->action_data;
2862
2863 track_val = get_track_val(track_data->hist_data, context->elt,
2864 track_data->action_data);
2865
2866 if (!action->track_data.check_val(track_data->track_val, track_val))
2867 return false;
2868
2869 track_data->track_val = track_val;
2870 memcpy(track_data->key, context->key, track_data->key_len);
2871
2872 elt_data = context->elt->private_data;
2873 track_elt_data = track_data->elt.private_data;
2874 if (elt_data->comm)
2875 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN);
2876
2877 track_data->updated = true;
2878
2879 return true;
2880 }
2881
save_track_data_snapshot(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)2882 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
2883 struct tracing_map_elt *elt, void *rec,
2884 struct ring_buffer_event *rbe, void *key,
2885 struct action_data *data,
2886 u64 *var_ref_vals)
2887 {
2888 struct trace_event_file *file = hist_data->event_file;
2889 struct snapshot_context context;
2890
2891 context.elt = elt;
2892 context.key = key;
2893
2894 tracing_snapshot_cond(file->tr, &context);
2895 }
2896
2897 static void hist_trigger_print_key(struct seq_file *m,
2898 struct hist_trigger_data *hist_data,
2899 void *key,
2900 struct tracing_map_elt *elt);
2901
snapshot_action(struct hist_trigger_data * hist_data)2902 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
2903 {
2904 unsigned int i;
2905
2906 if (!hist_data->n_actions)
2907 return NULL;
2908
2909 for (i = 0; i < hist_data->n_actions; i++) {
2910 struct action_data *data = hist_data->actions[i];
2911
2912 if (data->action == ACTION_SNAPSHOT)
2913 return data;
2914 }
2915
2916 return NULL;
2917 }
2918
track_data_snapshot_print(struct seq_file * m,struct hist_trigger_data * hist_data)2919 static void track_data_snapshot_print(struct seq_file *m,
2920 struct hist_trigger_data *hist_data)
2921 {
2922 struct trace_event_file *file = hist_data->event_file;
2923 struct track_data *track_data;
2924 struct action_data *action;
2925
2926 track_data = tracing_cond_snapshot_data(file->tr);
2927 if (!track_data)
2928 return;
2929
2930 if (!track_data->updated)
2931 return;
2932
2933 action = snapshot_action(hist_data);
2934 if (!action)
2935 return;
2936
2937 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n");
2938 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu",
2939 action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
2940 action->track_data.var_str, track_data->track_val);
2941
2942 seq_puts(m, "\ttriggered by event with key: ");
2943 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt);
2944 seq_putc(m, '\n');
2945 }
2946 #else
cond_snapshot_update(struct trace_array * tr,void * cond_data)2947 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
2948 {
2949 return false;
2950 }
save_track_data_snapshot(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)2951 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
2952 struct tracing_map_elt *elt, void *rec,
2953 struct ring_buffer_event *rbe, void *key,
2954 struct action_data *data,
2955 u64 *var_ref_vals) {}
track_data_snapshot_print(struct seq_file * m,struct hist_trigger_data * hist_data)2956 static void track_data_snapshot_print(struct seq_file *m,
2957 struct hist_trigger_data *hist_data) {}
2958 #endif /* CONFIG_TRACER_SNAPSHOT */
2959
track_data_print(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)2960 static void track_data_print(struct seq_file *m,
2961 struct hist_trigger_data *hist_data,
2962 struct tracing_map_elt *elt,
2963 struct action_data *data)
2964 {
2965 u64 track_val = get_track_val(hist_data, elt, data);
2966 unsigned int i, save_var_idx;
2967
2968 if (data->handler == HANDLER_ONMAX)
2969 seq_printf(m, "\n\tmax: %10llu", track_val);
2970 else if (data->handler == HANDLER_ONCHANGE)
2971 seq_printf(m, "\n\tchanged: %10llu", track_val);
2972
2973 if (data->action == ACTION_SNAPSHOT)
2974 return;
2975
2976 for (i = 0; i < hist_data->n_save_vars; i++) {
2977 struct hist_field *save_val = hist_data->save_vars[i]->val;
2978 struct hist_field *save_var = hist_data->save_vars[i]->var;
2979 u64 val;
2980
2981 save_var_idx = save_var->var.idx;
2982
2983 val = tracing_map_read_var(elt, save_var_idx);
2984
2985 if (save_val->flags & HIST_FIELD_FL_STRING) {
2986 seq_printf(m, " %s: %-32s", save_var->var.name,
2987 (char *)(uintptr_t)(val));
2988 } else
2989 seq_printf(m, " %s: %10llu", save_var->var.name, val);
2990 }
2991 }
2992
ontrack_action(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)2993 static void ontrack_action(struct hist_trigger_data *hist_data,
2994 struct tracing_map_elt *elt, void *rec,
2995 struct ring_buffer_event *rbe, void *key,
2996 struct action_data *data, u64 *var_ref_vals)
2997 {
2998 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx];
2999
3000 if (check_track_val(elt, data, var_val)) {
3001 save_track_val(hist_data, elt, data, var_val);
3002 save_track_data(hist_data, elt, rec, rbe, key, data, var_ref_vals);
3003 }
3004 }
3005
action_data_destroy(struct action_data * data)3006 static void action_data_destroy(struct action_data *data)
3007 {
3008 unsigned int i;
3009
3010 lockdep_assert_held(&event_mutex);
3011
3012 kfree(data->action_name);
3013
3014 for (i = 0; i < data->n_params; i++)
3015 kfree(data->params[i]);
3016
3017 if (data->synth_event)
3018 data->synth_event->ref--;
3019
3020 kfree(data->synth_event_name);
3021
3022 kfree(data);
3023 }
3024
track_data_destroy(struct hist_trigger_data * hist_data,struct action_data * data)3025 static void track_data_destroy(struct hist_trigger_data *hist_data,
3026 struct action_data *data)
3027 {
3028 struct trace_event_file *file = hist_data->event_file;
3029
3030 destroy_hist_field(data->track_data.track_var, 0);
3031
3032 if (data->action == ACTION_SNAPSHOT) {
3033 struct track_data *track_data;
3034
3035 track_data = tracing_cond_snapshot_data(file->tr);
3036 if (track_data && track_data->hist_data == hist_data) {
3037 tracing_snapshot_cond_disable(file->tr);
3038 track_data_free(track_data);
3039 }
3040 }
3041
3042 kfree(data->track_data.var_str);
3043
3044 action_data_destroy(data);
3045 }
3046
3047 static int action_create(struct hist_trigger_data *hist_data,
3048 struct action_data *data);
3049
track_data_create(struct hist_trigger_data * hist_data,struct action_data * data)3050 static int track_data_create(struct hist_trigger_data *hist_data,
3051 struct action_data *data)
3052 {
3053 struct hist_field *var_field, *ref_field, *track_var = NULL;
3054 struct trace_event_file *file = hist_data->event_file;
3055 struct trace_array *tr = file->tr;
3056 char *track_data_var_str;
3057 int ret = 0;
3058
3059 track_data_var_str = data->track_data.var_str;
3060 if (track_data_var_str[0] != '$') {
3061 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str));
3062 return -EINVAL;
3063 }
3064 track_data_var_str++;
3065
3066 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str);
3067 if (!var_field) {
3068 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str));
3069 return -EINVAL;
3070 }
3071
3072 ref_field = create_var_ref(hist_data, var_field, NULL, NULL);
3073 if (!ref_field)
3074 return -ENOMEM;
3075
3076 data->track_data.var_ref = ref_field;
3077
3078 if (data->handler == HANDLER_ONMAX)
3079 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64");
3080 if (IS_ERR(track_var)) {
3081 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3082 ret = PTR_ERR(track_var);
3083 goto out;
3084 }
3085
3086 if (data->handler == HANDLER_ONCHANGE)
3087 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64");
3088 if (IS_ERR(track_var)) {
3089 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3090 ret = PTR_ERR(track_var);
3091 goto out;
3092 }
3093 data->track_data.track_var = track_var;
3094
3095 ret = action_create(hist_data, data);
3096 out:
3097 return ret;
3098 }
3099
parse_action_params(struct trace_array * tr,char * params,struct action_data * data)3100 static int parse_action_params(struct trace_array *tr, char *params,
3101 struct action_data *data)
3102 {
3103 char *param, *saved_param;
3104 bool first_param = true;
3105 int ret = 0;
3106
3107 while (params) {
3108 if (data->n_params >= SYNTH_FIELDS_MAX) {
3109 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0);
3110 goto out;
3111 }
3112
3113 param = strsep(¶ms, ",");
3114 if (!param) {
3115 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0);
3116 ret = -EINVAL;
3117 goto out;
3118 }
3119
3120 param = strstrip(param);
3121 if (strlen(param) < 2) {
3122 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param));
3123 ret = -EINVAL;
3124 goto out;
3125 }
3126
3127 saved_param = kstrdup(param, GFP_KERNEL);
3128 if (!saved_param) {
3129 ret = -ENOMEM;
3130 goto out;
3131 }
3132
3133 if (first_param && data->use_trace_keyword) {
3134 data->synth_event_name = saved_param;
3135 first_param = false;
3136 continue;
3137 }
3138 first_param = false;
3139
3140 data->params[data->n_params++] = saved_param;
3141 }
3142 out:
3143 return ret;
3144 }
3145
action_parse(struct trace_array * tr,char * str,struct action_data * data,enum handler_id handler)3146 static int action_parse(struct trace_array *tr, char *str, struct action_data *data,
3147 enum handler_id handler)
3148 {
3149 char *action_name;
3150 int ret = 0;
3151
3152 strsep(&str, ".");
3153 if (!str) {
3154 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3155 ret = -EINVAL;
3156 goto out;
3157 }
3158
3159 action_name = strsep(&str, "(");
3160 if (!action_name || !str) {
3161 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3162 ret = -EINVAL;
3163 goto out;
3164 }
3165
3166 if (str_has_prefix(action_name, "save")) {
3167 char *params = strsep(&str, ")");
3168
3169 if (!params) {
3170 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0);
3171 ret = -EINVAL;
3172 goto out;
3173 }
3174
3175 ret = parse_action_params(tr, params, data);
3176 if (ret)
3177 goto out;
3178
3179 if (handler == HANDLER_ONMAX)
3180 data->track_data.check_val = check_track_val_max;
3181 else if (handler == HANDLER_ONCHANGE)
3182 data->track_data.check_val = check_track_val_changed;
3183 else {
3184 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3185 ret = -EINVAL;
3186 goto out;
3187 }
3188
3189 data->track_data.save_data = save_track_data_vars;
3190 data->fn = ontrack_action;
3191 data->action = ACTION_SAVE;
3192 } else if (str_has_prefix(action_name, "snapshot")) {
3193 char *params = strsep(&str, ")");
3194
3195 if (!str) {
3196 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params));
3197 ret = -EINVAL;
3198 goto out;
3199 }
3200
3201 if (handler == HANDLER_ONMAX)
3202 data->track_data.check_val = check_track_val_max;
3203 else if (handler == HANDLER_ONCHANGE)
3204 data->track_data.check_val = check_track_val_changed;
3205 else {
3206 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3207 ret = -EINVAL;
3208 goto out;
3209 }
3210
3211 data->track_data.save_data = save_track_data_snapshot;
3212 data->fn = ontrack_action;
3213 data->action = ACTION_SNAPSHOT;
3214 } else {
3215 char *params = strsep(&str, ")");
3216
3217 if (str_has_prefix(action_name, "trace"))
3218 data->use_trace_keyword = true;
3219
3220 if (params) {
3221 ret = parse_action_params(tr, params, data);
3222 if (ret)
3223 goto out;
3224 }
3225
3226 if (handler == HANDLER_ONMAX)
3227 data->track_data.check_val = check_track_val_max;
3228 else if (handler == HANDLER_ONCHANGE)
3229 data->track_data.check_val = check_track_val_changed;
3230
3231 if (handler != HANDLER_ONMATCH) {
3232 data->track_data.save_data = action_trace;
3233 data->fn = ontrack_action;
3234 } else
3235 data->fn = action_trace;
3236
3237 data->action = ACTION_TRACE;
3238 }
3239
3240 data->action_name = kstrdup(action_name, GFP_KERNEL);
3241 if (!data->action_name) {
3242 ret = -ENOMEM;
3243 goto out;
3244 }
3245
3246 data->handler = handler;
3247 out:
3248 return ret;
3249 }
3250
track_data_parse(struct hist_trigger_data * hist_data,char * str,enum handler_id handler)3251 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data,
3252 char *str, enum handler_id handler)
3253 {
3254 struct action_data *data;
3255 int ret = -EINVAL;
3256 char *var_str;
3257
3258 data = kzalloc(sizeof(*data), GFP_KERNEL);
3259 if (!data)
3260 return ERR_PTR(-ENOMEM);
3261
3262 var_str = strsep(&str, ")");
3263 if (!var_str || !str) {
3264 ret = -EINVAL;
3265 goto free;
3266 }
3267
3268 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL);
3269 if (!data->track_data.var_str) {
3270 ret = -ENOMEM;
3271 goto free;
3272 }
3273
3274 ret = action_parse(hist_data->event_file->tr, str, data, handler);
3275 if (ret)
3276 goto free;
3277 out:
3278 return data;
3279 free:
3280 track_data_destroy(hist_data, data);
3281 data = ERR_PTR(ret);
3282 goto out;
3283 }
3284
onmatch_destroy(struct action_data * data)3285 static void onmatch_destroy(struct action_data *data)
3286 {
3287 kfree(data->match_data.event);
3288 kfree(data->match_data.event_system);
3289
3290 action_data_destroy(data);
3291 }
3292
destroy_field_var(struct field_var * field_var)3293 static void destroy_field_var(struct field_var *field_var)
3294 {
3295 if (!field_var)
3296 return;
3297
3298 destroy_hist_field(field_var->var, 0);
3299 destroy_hist_field(field_var->val, 0);
3300
3301 kfree(field_var);
3302 }
3303
destroy_field_vars(struct hist_trigger_data * hist_data)3304 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3305 {
3306 unsigned int i;
3307
3308 for (i = 0; i < hist_data->n_field_vars; i++)
3309 destroy_field_var(hist_data->field_vars[i]);
3310
3311 for (i = 0; i < hist_data->n_save_vars; i++)
3312 destroy_field_var(hist_data->save_vars[i]);
3313 }
3314
save_field_var(struct hist_trigger_data * hist_data,struct field_var * field_var)3315 static void save_field_var(struct hist_trigger_data *hist_data,
3316 struct field_var *field_var)
3317 {
3318 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3319
3320 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3321 hist_data->n_field_var_str++;
3322 }
3323
3324
check_synth_field(struct synth_event * event,struct hist_field * hist_field,unsigned int field_pos)3325 static int check_synth_field(struct synth_event *event,
3326 struct hist_field *hist_field,
3327 unsigned int field_pos)
3328 {
3329 struct synth_field *field;
3330
3331 if (field_pos >= event->n_fields)
3332 return -EINVAL;
3333
3334 field = event->fields[field_pos];
3335
3336 /*
3337 * A dynamic string synth field can accept static or
3338 * dynamic. A static string synth field can only accept a
3339 * same-sized static string, which is checked for later.
3340 */
3341 if (strstr(hist_field->type, "char[") && field->is_string
3342 && field->is_dynamic)
3343 return 0;
3344
3345 if (strcmp(field->type, hist_field->type) != 0) {
3346 if (field->size != hist_field->size ||
3347 (!field->is_string && field->is_signed != hist_field->is_signed))
3348 return -EINVAL;
3349 }
3350
3351 return 0;
3352 }
3353
3354 static struct hist_field *
trace_action_find_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3355 trace_action_find_var(struct hist_trigger_data *hist_data,
3356 struct action_data *data,
3357 char *system, char *event, char *var)
3358 {
3359 struct trace_array *tr = hist_data->event_file->tr;
3360 struct hist_field *hist_field;
3361
3362 var++; /* skip '$' */
3363
3364 hist_field = find_target_event_var(hist_data, system, event, var);
3365 if (!hist_field) {
3366 if (!system && data->handler == HANDLER_ONMATCH) {
3367 system = data->match_data.event_system;
3368 event = data->match_data.event;
3369 }
3370
3371 hist_field = find_event_var(hist_data, system, event, var);
3372 }
3373
3374 if (!hist_field)
3375 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var));
3376
3377 return hist_field;
3378 }
3379
3380 static struct hist_field *
trace_action_create_field_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3381 trace_action_create_field_var(struct hist_trigger_data *hist_data,
3382 struct action_data *data, char *system,
3383 char *event, char *var)
3384 {
3385 struct hist_field *hist_field = NULL;
3386 struct field_var *field_var;
3387
3388 /*
3389 * First try to create a field var on the target event (the
3390 * currently being defined). This will create a variable for
3391 * unqualified fields on the target event, or if qualified,
3392 * target fields that have qualified names matching the target.
3393 */
3394 field_var = create_target_field_var(hist_data, system, event, var);
3395
3396 if (field_var && !IS_ERR(field_var)) {
3397 save_field_var(hist_data, field_var);
3398 hist_field = field_var->var;
3399 } else {
3400 field_var = NULL;
3401 /*
3402 * If no explicit system.event is specfied, default to
3403 * looking for fields on the onmatch(system.event.xxx)
3404 * event.
3405 */
3406 if (!system && data->handler == HANDLER_ONMATCH) {
3407 system = data->match_data.event_system;
3408 event = data->match_data.event;
3409 }
3410
3411 if (!event)
3412 goto free;
3413 /*
3414 * At this point, we're looking at a field on another
3415 * event. Because we can't modify a hist trigger on
3416 * another event to add a variable for a field, we need
3417 * to create a new trigger on that event and create the
3418 * variable at the same time.
3419 */
3420 hist_field = create_field_var_hist(hist_data, system, event, var);
3421 if (IS_ERR(hist_field))
3422 goto free;
3423 }
3424 out:
3425 return hist_field;
3426 free:
3427 destroy_field_var(field_var);
3428 hist_field = NULL;
3429 goto out;
3430 }
3431
trace_action_create(struct hist_trigger_data * hist_data,struct action_data * data)3432 static int trace_action_create(struct hist_trigger_data *hist_data,
3433 struct action_data *data)
3434 {
3435 struct trace_array *tr = hist_data->event_file->tr;
3436 char *event_name, *param, *system = NULL;
3437 struct hist_field *hist_field, *var_ref;
3438 unsigned int i;
3439 unsigned int field_pos = 0;
3440 struct synth_event *event;
3441 char *synth_event_name;
3442 int var_ref_idx, ret = 0;
3443
3444 lockdep_assert_held(&event_mutex);
3445
3446 if (data->use_trace_keyword)
3447 synth_event_name = data->synth_event_name;
3448 else
3449 synth_event_name = data->action_name;
3450
3451 event = find_synth_event(synth_event_name);
3452 if (!event) {
3453 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name));
3454 return -EINVAL;
3455 }
3456
3457 event->ref++;
3458
3459 for (i = 0; i < data->n_params; i++) {
3460 char *p;
3461
3462 p = param = kstrdup(data->params[i], GFP_KERNEL);
3463 if (!param) {
3464 ret = -ENOMEM;
3465 goto err;
3466 }
3467
3468 system = strsep(¶m, ".");
3469 if (!param) {
3470 param = (char *)system;
3471 system = event_name = NULL;
3472 } else {
3473 event_name = strsep(¶m, ".");
3474 if (!param) {
3475 kfree(p);
3476 ret = -EINVAL;
3477 goto err;
3478 }
3479 }
3480
3481 if (param[0] == '$')
3482 hist_field = trace_action_find_var(hist_data, data,
3483 system, event_name,
3484 param);
3485 else
3486 hist_field = trace_action_create_field_var(hist_data,
3487 data,
3488 system,
3489 event_name,
3490 param);
3491
3492 if (!hist_field) {
3493 kfree(p);
3494 ret = -EINVAL;
3495 goto err;
3496 }
3497
3498 if (check_synth_field(event, hist_field, field_pos) == 0) {
3499 var_ref = create_var_ref(hist_data, hist_field,
3500 system, event_name);
3501 if (!var_ref) {
3502 kfree(p);
3503 ret = -ENOMEM;
3504 goto err;
3505 }
3506
3507 var_ref_idx = find_var_ref_idx(hist_data, var_ref);
3508 if (WARN_ON(var_ref_idx < 0)) {
3509 kfree(p);
3510 ret = var_ref_idx;
3511 goto err;
3512 }
3513
3514 data->var_ref_idx[i] = var_ref_idx;
3515
3516 field_pos++;
3517 kfree(p);
3518 continue;
3519 }
3520
3521 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param));
3522 kfree(p);
3523 ret = -EINVAL;
3524 goto err;
3525 }
3526
3527 if (field_pos != event->n_fields) {
3528 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name));
3529 ret = -EINVAL;
3530 goto err;
3531 }
3532
3533 data->synth_event = event;
3534 out:
3535 return ret;
3536 err:
3537 event->ref--;
3538
3539 goto out;
3540 }
3541
action_create(struct hist_trigger_data * hist_data,struct action_data * data)3542 static int action_create(struct hist_trigger_data *hist_data,
3543 struct action_data *data)
3544 {
3545 struct trace_event_file *file = hist_data->event_file;
3546 struct trace_array *tr = file->tr;
3547 struct track_data *track_data;
3548 struct field_var *field_var;
3549 unsigned int i;
3550 char *param;
3551 int ret = 0;
3552
3553 if (data->action == ACTION_TRACE)
3554 return trace_action_create(hist_data, data);
3555
3556 if (data->action == ACTION_SNAPSHOT) {
3557 track_data = track_data_alloc(hist_data->key_size, data, hist_data);
3558 if (IS_ERR(track_data)) {
3559 ret = PTR_ERR(track_data);
3560 goto out;
3561 }
3562
3563 ret = tracing_snapshot_cond_enable(file->tr, track_data,
3564 cond_snapshot_update);
3565 if (ret)
3566 track_data_free(track_data);
3567
3568 goto out;
3569 }
3570
3571 if (data->action == ACTION_SAVE) {
3572 if (hist_data->n_save_vars) {
3573 ret = -EEXIST;
3574 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0);
3575 goto out;
3576 }
3577
3578 for (i = 0; i < data->n_params; i++) {
3579 param = kstrdup(data->params[i], GFP_KERNEL);
3580 if (!param) {
3581 ret = -ENOMEM;
3582 goto out;
3583 }
3584
3585 field_var = create_target_field_var(hist_data, NULL, NULL, param);
3586 if (IS_ERR(field_var)) {
3587 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL,
3588 errpos(param));
3589 ret = PTR_ERR(field_var);
3590 kfree(param);
3591 goto out;
3592 }
3593
3594 hist_data->save_vars[hist_data->n_save_vars++] = field_var;
3595 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3596 hist_data->n_save_var_str++;
3597 kfree(param);
3598 }
3599 }
3600 out:
3601 return ret;
3602 }
3603
onmatch_create(struct hist_trigger_data * hist_data,struct action_data * data)3604 static int onmatch_create(struct hist_trigger_data *hist_data,
3605 struct action_data *data)
3606 {
3607 return action_create(hist_data, data);
3608 }
3609
onmatch_parse(struct trace_array * tr,char * str)3610 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
3611 {
3612 char *match_event, *match_event_system;
3613 struct action_data *data;
3614 int ret = -EINVAL;
3615
3616 data = kzalloc(sizeof(*data), GFP_KERNEL);
3617 if (!data)
3618 return ERR_PTR(-ENOMEM);
3619
3620 match_event = strsep(&str, ")");
3621 if (!match_event || !str) {
3622 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event));
3623 goto free;
3624 }
3625
3626 match_event_system = strsep(&match_event, ".");
3627 if (!match_event) {
3628 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system));
3629 goto free;
3630 }
3631
3632 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
3633 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event));
3634 goto free;
3635 }
3636
3637 data->match_data.event = kstrdup(match_event, GFP_KERNEL);
3638 if (!data->match_data.event) {
3639 ret = -ENOMEM;
3640 goto free;
3641 }
3642
3643 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL);
3644 if (!data->match_data.event_system) {
3645 ret = -ENOMEM;
3646 goto free;
3647 }
3648
3649 ret = action_parse(tr, str, data, HANDLER_ONMATCH);
3650 if (ret)
3651 goto free;
3652 out:
3653 return data;
3654 free:
3655 onmatch_destroy(data);
3656 data = ERR_PTR(ret);
3657 goto out;
3658 }
3659
create_hitcount_val(struct hist_trigger_data * hist_data)3660 static int create_hitcount_val(struct hist_trigger_data *hist_data)
3661 {
3662 hist_data->fields[HITCOUNT_IDX] =
3663 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
3664 if (!hist_data->fields[HITCOUNT_IDX])
3665 return -ENOMEM;
3666
3667 hist_data->n_vals++;
3668 hist_data->n_fields++;
3669
3670 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
3671 return -EINVAL;
3672
3673 return 0;
3674 }
3675
__create_val_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * var_name,char * field_str,unsigned long flags)3676 static int __create_val_field(struct hist_trigger_data *hist_data,
3677 unsigned int val_idx,
3678 struct trace_event_file *file,
3679 char *var_name, char *field_str,
3680 unsigned long flags)
3681 {
3682 struct hist_field *hist_field;
3683 int ret = 0;
3684
3685 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
3686 if (IS_ERR(hist_field)) {
3687 ret = PTR_ERR(hist_field);
3688 goto out;
3689 }
3690
3691 hist_data->fields[val_idx] = hist_field;
3692
3693 ++hist_data->n_vals;
3694 ++hist_data->n_fields;
3695
3696 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3697 ret = -EINVAL;
3698 out:
3699 return ret;
3700 }
3701
create_val_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * field_str)3702 static int create_val_field(struct hist_trigger_data *hist_data,
3703 unsigned int val_idx,
3704 struct trace_event_file *file,
3705 char *field_str)
3706 {
3707 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
3708 return -EINVAL;
3709
3710 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
3711 }
3712
create_var_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * var_name,char * expr_str)3713 static int create_var_field(struct hist_trigger_data *hist_data,
3714 unsigned int val_idx,
3715 struct trace_event_file *file,
3716 char *var_name, char *expr_str)
3717 {
3718 struct trace_array *tr = hist_data->event_file->tr;
3719 unsigned long flags = 0;
3720 int ret;
3721
3722 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3723 return -EINVAL;
3724
3725 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
3726 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name));
3727 return -EINVAL;
3728 }
3729
3730 flags |= HIST_FIELD_FL_VAR;
3731 hist_data->n_vars++;
3732 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
3733 return -EINVAL;
3734
3735 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
3736
3737 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING)
3738 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
3739
3740 return ret;
3741 }
3742
create_val_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3743 static int create_val_fields(struct hist_trigger_data *hist_data,
3744 struct trace_event_file *file)
3745 {
3746 char *fields_str, *field_str;
3747 unsigned int i, j = 1;
3748 int ret;
3749
3750 ret = create_hitcount_val(hist_data);
3751 if (ret)
3752 goto out;
3753
3754 fields_str = hist_data->attrs->vals_str;
3755 if (!fields_str)
3756 goto out;
3757
3758 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
3759 j < TRACING_MAP_VALS_MAX; i++) {
3760 field_str = strsep(&fields_str, ",");
3761 if (!field_str)
3762 break;
3763
3764 if (strcmp(field_str, "hitcount") == 0)
3765 continue;
3766
3767 ret = create_val_field(hist_data, j++, file, field_str);
3768 if (ret)
3769 goto out;
3770 }
3771
3772 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
3773 ret = -EINVAL;
3774 out:
3775 return ret;
3776 }
3777
create_key_field(struct hist_trigger_data * hist_data,unsigned int key_idx,unsigned int key_offset,struct trace_event_file * file,char * field_str)3778 static int create_key_field(struct hist_trigger_data *hist_data,
3779 unsigned int key_idx,
3780 unsigned int key_offset,
3781 struct trace_event_file *file,
3782 char *field_str)
3783 {
3784 struct trace_array *tr = hist_data->event_file->tr;
3785 struct hist_field *hist_field = NULL;
3786 unsigned long flags = 0;
3787 unsigned int key_size;
3788 int ret = 0;
3789
3790 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
3791 return -EINVAL;
3792
3793 flags |= HIST_FIELD_FL_KEY;
3794
3795 if (strcmp(field_str, "stacktrace") == 0) {
3796 flags |= HIST_FIELD_FL_STACKTRACE;
3797 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
3798 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
3799 } else {
3800 hist_field = parse_expr(hist_data, file, field_str, flags,
3801 NULL, 0);
3802 if (IS_ERR(hist_field)) {
3803 ret = PTR_ERR(hist_field);
3804 goto out;
3805 }
3806
3807 if (field_has_hist_vars(hist_field, 0)) {
3808 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str));
3809 destroy_hist_field(hist_field, 0);
3810 ret = -EINVAL;
3811 goto out;
3812 }
3813
3814 key_size = hist_field->size;
3815 }
3816
3817 hist_data->fields[key_idx] = hist_field;
3818
3819 key_size = ALIGN(key_size, sizeof(u64));
3820 hist_data->fields[key_idx]->size = key_size;
3821 hist_data->fields[key_idx]->offset = key_offset;
3822
3823 hist_data->key_size += key_size;
3824
3825 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
3826 ret = -EINVAL;
3827 goto out;
3828 }
3829
3830 hist_data->n_keys++;
3831 hist_data->n_fields++;
3832
3833 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
3834 return -EINVAL;
3835
3836 ret = key_size;
3837 out:
3838 return ret;
3839 }
3840
create_key_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3841 static int create_key_fields(struct hist_trigger_data *hist_data,
3842 struct trace_event_file *file)
3843 {
3844 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
3845 char *fields_str, *field_str;
3846 int ret = -EINVAL;
3847
3848 fields_str = hist_data->attrs->keys_str;
3849 if (!fields_str)
3850 goto out;
3851
3852 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
3853 field_str = strsep(&fields_str, ",");
3854 if (!field_str)
3855 break;
3856 ret = create_key_field(hist_data, i, key_offset,
3857 file, field_str);
3858 if (ret < 0)
3859 goto out;
3860 key_offset += ret;
3861 }
3862 if (fields_str) {
3863 ret = -EINVAL;
3864 goto out;
3865 }
3866 ret = 0;
3867 out:
3868 return ret;
3869 }
3870
create_var_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3871 static int create_var_fields(struct hist_trigger_data *hist_data,
3872 struct trace_event_file *file)
3873 {
3874 unsigned int i, j = hist_data->n_vals;
3875 int ret = 0;
3876
3877 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
3878
3879 for (i = 0; i < n_vars; i++) {
3880 char *var_name = hist_data->attrs->var_defs.name[i];
3881 char *expr = hist_data->attrs->var_defs.expr[i];
3882
3883 ret = create_var_field(hist_data, j++, file, var_name, expr);
3884 if (ret)
3885 goto out;
3886 }
3887 out:
3888 return ret;
3889 }
3890
free_var_defs(struct hist_trigger_data * hist_data)3891 static void free_var_defs(struct hist_trigger_data *hist_data)
3892 {
3893 unsigned int i;
3894
3895 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
3896 kfree(hist_data->attrs->var_defs.name[i]);
3897 kfree(hist_data->attrs->var_defs.expr[i]);
3898 }
3899
3900 hist_data->attrs->var_defs.n_vars = 0;
3901 }
3902
parse_var_defs(struct hist_trigger_data * hist_data)3903 static int parse_var_defs(struct hist_trigger_data *hist_data)
3904 {
3905 struct trace_array *tr = hist_data->event_file->tr;
3906 char *s, *str, *var_name, *field_str;
3907 unsigned int i, j, n_vars = 0;
3908 int ret = 0;
3909
3910 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
3911 str = hist_data->attrs->assignment_str[i];
3912 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
3913 field_str = strsep(&str, ",");
3914 if (!field_str)
3915 break;
3916
3917 var_name = strsep(&field_str, "=");
3918 if (!var_name || !field_str) {
3919 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT,
3920 errpos(var_name));
3921 ret = -EINVAL;
3922 goto free;
3923 }
3924
3925 if (n_vars == TRACING_MAP_VARS_MAX) {
3926 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name));
3927 ret = -EINVAL;
3928 goto free;
3929 }
3930
3931 s = kstrdup(var_name, GFP_KERNEL);
3932 if (!s) {
3933 ret = -ENOMEM;
3934 goto free;
3935 }
3936 hist_data->attrs->var_defs.name[n_vars] = s;
3937
3938 s = kstrdup(field_str, GFP_KERNEL);
3939 if (!s) {
3940 ret = -ENOMEM;
3941 goto free;
3942 }
3943 hist_data->attrs->var_defs.expr[n_vars++] = s;
3944
3945 hist_data->attrs->var_defs.n_vars = n_vars;
3946 }
3947 }
3948
3949 return ret;
3950 free:
3951 free_var_defs(hist_data);
3952
3953 return ret;
3954 }
3955
create_hist_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3956 static int create_hist_fields(struct hist_trigger_data *hist_data,
3957 struct trace_event_file *file)
3958 {
3959 int ret;
3960
3961 ret = parse_var_defs(hist_data);
3962 if (ret)
3963 goto out;
3964
3965 ret = create_val_fields(hist_data, file);
3966 if (ret)
3967 goto out;
3968
3969 ret = create_var_fields(hist_data, file);
3970 if (ret)
3971 goto out;
3972
3973 ret = create_key_fields(hist_data, file);
3974 if (ret)
3975 goto out;
3976 out:
3977 free_var_defs(hist_data);
3978
3979 return ret;
3980 }
3981
is_descending(struct trace_array * tr,const char * str)3982 static int is_descending(struct trace_array *tr, const char *str)
3983 {
3984 if (!str)
3985 return 0;
3986
3987 if (strcmp(str, "descending") == 0)
3988 return 1;
3989
3990 if (strcmp(str, "ascending") == 0)
3991 return 0;
3992
3993 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str));
3994
3995 return -EINVAL;
3996 }
3997
create_sort_keys(struct hist_trigger_data * hist_data)3998 static int create_sort_keys(struct hist_trigger_data *hist_data)
3999 {
4000 struct trace_array *tr = hist_data->event_file->tr;
4001 char *fields_str = hist_data->attrs->sort_key_str;
4002 struct tracing_map_sort_key *sort_key;
4003 int descending, ret = 0;
4004 unsigned int i, j, k;
4005
4006 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4007
4008 if (!fields_str)
4009 goto out;
4010
4011 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4012 struct hist_field *hist_field;
4013 char *field_str, *field_name;
4014 const char *test_name;
4015
4016 sort_key = &hist_data->sort_keys[i];
4017
4018 field_str = strsep(&fields_str, ",");
4019 if (!field_str)
4020 break;
4021
4022 if (!*field_str) {
4023 ret = -EINVAL;
4024 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4025 break;
4026 }
4027
4028 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4029 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort="));
4030 ret = -EINVAL;
4031 break;
4032 }
4033
4034 field_name = strsep(&field_str, ".");
4035 if (!field_name || !*field_name) {
4036 ret = -EINVAL;
4037 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4038 break;
4039 }
4040
4041 if (strcmp(field_name, "hitcount") == 0) {
4042 descending = is_descending(tr, field_str);
4043 if (descending < 0) {
4044 ret = descending;
4045 break;
4046 }
4047 sort_key->descending = descending;
4048 continue;
4049 }
4050
4051 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4052 unsigned int idx;
4053
4054 hist_field = hist_data->fields[j];
4055 if (hist_field->flags & HIST_FIELD_FL_VAR)
4056 continue;
4057
4058 idx = k++;
4059
4060 test_name = hist_field_name(hist_field, 0);
4061
4062 if (strcmp(field_name, test_name) == 0) {
4063 sort_key->field_idx = idx;
4064 descending = is_descending(tr, field_str);
4065 if (descending < 0) {
4066 ret = descending;
4067 goto out;
4068 }
4069 sort_key->descending = descending;
4070 break;
4071 }
4072 }
4073 if (j == hist_data->n_fields) {
4074 ret = -EINVAL;
4075 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name));
4076 break;
4077 }
4078 }
4079
4080 hist_data->n_sort_keys = i;
4081 out:
4082 return ret;
4083 }
4084
destroy_actions(struct hist_trigger_data * hist_data)4085 static void destroy_actions(struct hist_trigger_data *hist_data)
4086 {
4087 unsigned int i;
4088
4089 for (i = 0; i < hist_data->n_actions; i++) {
4090 struct action_data *data = hist_data->actions[i];
4091
4092 if (data->handler == HANDLER_ONMATCH)
4093 onmatch_destroy(data);
4094 else if (data->handler == HANDLER_ONMAX ||
4095 data->handler == HANDLER_ONCHANGE)
4096 track_data_destroy(hist_data, data);
4097 else
4098 kfree(data);
4099 }
4100 }
4101
parse_actions(struct hist_trigger_data * hist_data)4102 static int parse_actions(struct hist_trigger_data *hist_data)
4103 {
4104 struct trace_array *tr = hist_data->event_file->tr;
4105 struct action_data *data;
4106 unsigned int i;
4107 int ret = 0;
4108 char *str;
4109 int len;
4110
4111 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4112 str = hist_data->attrs->action_str[i];
4113
4114 if ((len = str_has_prefix(str, "onmatch("))) {
4115 char *action_str = str + len;
4116
4117 data = onmatch_parse(tr, action_str);
4118 if (IS_ERR(data)) {
4119 ret = PTR_ERR(data);
4120 break;
4121 }
4122 } else if ((len = str_has_prefix(str, "onmax("))) {
4123 char *action_str = str + len;
4124
4125 data = track_data_parse(hist_data, action_str,
4126 HANDLER_ONMAX);
4127 if (IS_ERR(data)) {
4128 ret = PTR_ERR(data);
4129 break;
4130 }
4131 } else if ((len = str_has_prefix(str, "onchange("))) {
4132 char *action_str = str + len;
4133
4134 data = track_data_parse(hist_data, action_str,
4135 HANDLER_ONCHANGE);
4136 if (IS_ERR(data)) {
4137 ret = PTR_ERR(data);
4138 break;
4139 }
4140 } else {
4141 ret = -EINVAL;
4142 break;
4143 }
4144
4145 hist_data->actions[hist_data->n_actions++] = data;
4146 }
4147
4148 return ret;
4149 }
4150
create_actions(struct hist_trigger_data * hist_data)4151 static int create_actions(struct hist_trigger_data *hist_data)
4152 {
4153 struct action_data *data;
4154 unsigned int i;
4155 int ret = 0;
4156
4157 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4158 data = hist_data->actions[i];
4159
4160 if (data->handler == HANDLER_ONMATCH) {
4161 ret = onmatch_create(hist_data, data);
4162 if (ret)
4163 break;
4164 } else if (data->handler == HANDLER_ONMAX ||
4165 data->handler == HANDLER_ONCHANGE) {
4166 ret = track_data_create(hist_data, data);
4167 if (ret)
4168 break;
4169 } else {
4170 ret = -EINVAL;
4171 break;
4172 }
4173 }
4174
4175 return ret;
4176 }
4177
print_actions(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt)4178 static void print_actions(struct seq_file *m,
4179 struct hist_trigger_data *hist_data,
4180 struct tracing_map_elt *elt)
4181 {
4182 unsigned int i;
4183
4184 for (i = 0; i < hist_data->n_actions; i++) {
4185 struct action_data *data = hist_data->actions[i];
4186
4187 if (data->action == ACTION_SNAPSHOT)
4188 continue;
4189
4190 if (data->handler == HANDLER_ONMAX ||
4191 data->handler == HANDLER_ONCHANGE)
4192 track_data_print(m, hist_data, elt, data);
4193 }
4194 }
4195
print_action_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4196 static void print_action_spec(struct seq_file *m,
4197 struct hist_trigger_data *hist_data,
4198 struct action_data *data)
4199 {
4200 unsigned int i;
4201
4202 if (data->action == ACTION_SAVE) {
4203 for (i = 0; i < hist_data->n_save_vars; i++) {
4204 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name);
4205 if (i < hist_data->n_save_vars - 1)
4206 seq_puts(m, ",");
4207 }
4208 } else if (data->action == ACTION_TRACE) {
4209 if (data->use_trace_keyword)
4210 seq_printf(m, "%s", data->synth_event_name);
4211 for (i = 0; i < data->n_params; i++) {
4212 if (i || data->use_trace_keyword)
4213 seq_puts(m, ",");
4214 seq_printf(m, "%s", data->params[i]);
4215 }
4216 }
4217 }
4218
print_track_data_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4219 static void print_track_data_spec(struct seq_file *m,
4220 struct hist_trigger_data *hist_data,
4221 struct action_data *data)
4222 {
4223 if (data->handler == HANDLER_ONMAX)
4224 seq_puts(m, ":onmax(");
4225 else if (data->handler == HANDLER_ONCHANGE)
4226 seq_puts(m, ":onchange(");
4227 seq_printf(m, "%s", data->track_data.var_str);
4228 seq_printf(m, ").%s(", data->action_name);
4229
4230 print_action_spec(m, hist_data, data);
4231
4232 seq_puts(m, ")");
4233 }
4234
print_onmatch_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4235 static void print_onmatch_spec(struct seq_file *m,
4236 struct hist_trigger_data *hist_data,
4237 struct action_data *data)
4238 {
4239 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system,
4240 data->match_data.event);
4241
4242 seq_printf(m, "%s(", data->action_name);
4243
4244 print_action_spec(m, hist_data, data);
4245
4246 seq_puts(m, ")");
4247 }
4248
actions_match(struct hist_trigger_data * hist_data,struct hist_trigger_data * hist_data_test)4249 static bool actions_match(struct hist_trigger_data *hist_data,
4250 struct hist_trigger_data *hist_data_test)
4251 {
4252 unsigned int i, j;
4253
4254 if (hist_data->n_actions != hist_data_test->n_actions)
4255 return false;
4256
4257 for (i = 0; i < hist_data->n_actions; i++) {
4258 struct action_data *data = hist_data->actions[i];
4259 struct action_data *data_test = hist_data_test->actions[i];
4260 char *action_name, *action_name_test;
4261
4262 if (data->handler != data_test->handler)
4263 return false;
4264 if (data->action != data_test->action)
4265 return false;
4266
4267 if (data->n_params != data_test->n_params)
4268 return false;
4269
4270 for (j = 0; j < data->n_params; j++) {
4271 if (strcmp(data->params[j], data_test->params[j]) != 0)
4272 return false;
4273 }
4274
4275 if (data->use_trace_keyword)
4276 action_name = data->synth_event_name;
4277 else
4278 action_name = data->action_name;
4279
4280 if (data_test->use_trace_keyword)
4281 action_name_test = data_test->synth_event_name;
4282 else
4283 action_name_test = data_test->action_name;
4284
4285 if (strcmp(action_name, action_name_test) != 0)
4286 return false;
4287
4288 if (data->handler == HANDLER_ONMATCH) {
4289 if (strcmp(data->match_data.event_system,
4290 data_test->match_data.event_system) != 0)
4291 return false;
4292 if (strcmp(data->match_data.event,
4293 data_test->match_data.event) != 0)
4294 return false;
4295 } else if (data->handler == HANDLER_ONMAX ||
4296 data->handler == HANDLER_ONCHANGE) {
4297 if (strcmp(data->track_data.var_str,
4298 data_test->track_data.var_str) != 0)
4299 return false;
4300 }
4301 }
4302
4303 return true;
4304 }
4305
4306
print_actions_spec(struct seq_file * m,struct hist_trigger_data * hist_data)4307 static void print_actions_spec(struct seq_file *m,
4308 struct hist_trigger_data *hist_data)
4309 {
4310 unsigned int i;
4311
4312 for (i = 0; i < hist_data->n_actions; i++) {
4313 struct action_data *data = hist_data->actions[i];
4314
4315 if (data->handler == HANDLER_ONMATCH)
4316 print_onmatch_spec(m, hist_data, data);
4317 else if (data->handler == HANDLER_ONMAX ||
4318 data->handler == HANDLER_ONCHANGE)
4319 print_track_data_spec(m, hist_data, data);
4320 }
4321 }
4322
destroy_field_var_hists(struct hist_trigger_data * hist_data)4323 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4324 {
4325 unsigned int i;
4326
4327 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4328 kfree(hist_data->field_var_hists[i]->cmd);
4329 kfree(hist_data->field_var_hists[i]);
4330 }
4331 }
4332
destroy_hist_data(struct hist_trigger_data * hist_data)4333 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4334 {
4335 if (!hist_data)
4336 return;
4337
4338 destroy_hist_trigger_attrs(hist_data->attrs);
4339 destroy_hist_fields(hist_data);
4340 tracing_map_destroy(hist_data->map);
4341
4342 destroy_actions(hist_data);
4343 destroy_field_vars(hist_data);
4344 destroy_field_var_hists(hist_data);
4345
4346 kfree(hist_data);
4347 }
4348
create_tracing_map_fields(struct hist_trigger_data * hist_data)4349 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4350 {
4351 struct tracing_map *map = hist_data->map;
4352 struct ftrace_event_field *field;
4353 struct hist_field *hist_field;
4354 int i, idx = 0;
4355
4356 for_each_hist_field(i, hist_data) {
4357 hist_field = hist_data->fields[i];
4358 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4359 tracing_map_cmp_fn_t cmp_fn;
4360
4361 field = hist_field->field;
4362
4363 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4364 cmp_fn = tracing_map_cmp_none;
4365 else if (!field)
4366 cmp_fn = tracing_map_cmp_num(hist_field->size,
4367 hist_field->is_signed);
4368 else if (is_string_field(field))
4369 cmp_fn = tracing_map_cmp_string;
4370 else
4371 cmp_fn = tracing_map_cmp_num(field->size,
4372 field->is_signed);
4373 idx = tracing_map_add_key_field(map,
4374 hist_field->offset,
4375 cmp_fn);
4376 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4377 idx = tracing_map_add_sum_field(map);
4378
4379 if (idx < 0)
4380 return idx;
4381
4382 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4383 idx = tracing_map_add_var(map);
4384 if (idx < 0)
4385 return idx;
4386 hist_field->var.idx = idx;
4387 hist_field->var.hist_data = hist_data;
4388 }
4389 }
4390
4391 return 0;
4392 }
4393
4394 static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,struct hist_trigger_attrs * attrs,struct trace_event_file * file,bool remove)4395 create_hist_data(unsigned int map_bits,
4396 struct hist_trigger_attrs *attrs,
4397 struct trace_event_file *file,
4398 bool remove)
4399 {
4400 const struct tracing_map_ops *map_ops = NULL;
4401 struct hist_trigger_data *hist_data;
4402 int ret = 0;
4403
4404 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4405 if (!hist_data)
4406 return ERR_PTR(-ENOMEM);
4407
4408 hist_data->attrs = attrs;
4409 hist_data->remove = remove;
4410 hist_data->event_file = file;
4411
4412 ret = parse_actions(hist_data);
4413 if (ret)
4414 goto free;
4415
4416 ret = create_hist_fields(hist_data, file);
4417 if (ret)
4418 goto free;
4419
4420 ret = create_sort_keys(hist_data);
4421 if (ret)
4422 goto free;
4423
4424 map_ops = &hist_trigger_elt_data_ops;
4425
4426 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
4427 map_ops, hist_data);
4428 if (IS_ERR(hist_data->map)) {
4429 ret = PTR_ERR(hist_data->map);
4430 hist_data->map = NULL;
4431 goto free;
4432 }
4433
4434 ret = create_tracing_map_fields(hist_data);
4435 if (ret)
4436 goto free;
4437 out:
4438 return hist_data;
4439 free:
4440 hist_data->attrs = NULL;
4441
4442 destroy_hist_data(hist_data);
4443
4444 hist_data = ERR_PTR(ret);
4445
4446 goto out;
4447 }
4448
hist_trigger_elt_update(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,u64 * var_ref_vals)4449 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
4450 struct tracing_map_elt *elt, void *rec,
4451 struct ring_buffer_event *rbe,
4452 u64 *var_ref_vals)
4453 {
4454 struct hist_elt_data *elt_data;
4455 struct hist_field *hist_field;
4456 unsigned int i, var_idx;
4457 u64 hist_val;
4458
4459 elt_data = elt->private_data;
4460 elt_data->var_ref_vals = var_ref_vals;
4461
4462 for_each_hist_val_field(i, hist_data) {
4463 hist_field = hist_data->fields[i];
4464 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4465 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4466 var_idx = hist_field->var.idx;
4467
4468 if (hist_field->flags & HIST_FIELD_FL_STRING) {
4469 unsigned int str_start, var_str_idx, idx;
4470 char *str, *val_str;
4471 unsigned int size;
4472
4473 str_start = hist_data->n_field_var_str +
4474 hist_data->n_save_var_str;
4475 var_str_idx = hist_field->var_str_idx;
4476 idx = str_start + var_str_idx;
4477
4478 str = elt_data->field_var_str[idx];
4479 val_str = (char *)(uintptr_t)hist_val;
4480
4481 size = min(hist_field->size, STR_VAR_LEN_MAX);
4482 strscpy(str, val_str, size);
4483
4484 hist_val = (u64)(uintptr_t)str;
4485 }
4486 tracing_map_set_var(elt, var_idx, hist_val);
4487 continue;
4488 }
4489 tracing_map_update_sum(elt, i, hist_val);
4490 }
4491
4492 for_each_hist_key_field(i, hist_data) {
4493 hist_field = hist_data->fields[i];
4494 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4495 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4496 var_idx = hist_field->var.idx;
4497 tracing_map_set_var(elt, var_idx, hist_val);
4498 }
4499 }
4500
4501 update_field_vars(hist_data, elt, rbe, rec);
4502 }
4503
add_to_key(char * compound_key,void * key,struct hist_field * key_field,void * rec)4504 static inline void add_to_key(char *compound_key, void *key,
4505 struct hist_field *key_field, void *rec)
4506 {
4507 size_t size = key_field->size;
4508
4509 if (key_field->flags & HIST_FIELD_FL_STRING) {
4510 struct ftrace_event_field *field;
4511
4512 field = key_field->field;
4513 if (field->filter_type == FILTER_DYN_STRING)
4514 size = *(u32 *)(rec + field->offset) >> 16;
4515 else if (field->filter_type == FILTER_STATIC_STRING)
4516 size = field->size;
4517
4518 /* ensure NULL-termination */
4519 if (size > key_field->size - 1)
4520 size = key_field->size - 1;
4521
4522 strncpy(compound_key + key_field->offset, (char *)key, size);
4523 } else
4524 memcpy(compound_key + key_field->offset, key, size);
4525 }
4526
4527 static void
hist_trigger_actions(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,void * key,u64 * var_ref_vals)4528 hist_trigger_actions(struct hist_trigger_data *hist_data,
4529 struct tracing_map_elt *elt, void *rec,
4530 struct ring_buffer_event *rbe, void *key,
4531 u64 *var_ref_vals)
4532 {
4533 struct action_data *data;
4534 unsigned int i;
4535
4536 for (i = 0; i < hist_data->n_actions; i++) {
4537 data = hist_data->actions[i];
4538 data->fn(hist_data, elt, rec, rbe, key, data, var_ref_vals);
4539 }
4540 }
4541
event_hist_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * rbe)4542 static void event_hist_trigger(struct event_trigger_data *data, void *rec,
4543 struct ring_buffer_event *rbe)
4544 {
4545 struct hist_trigger_data *hist_data = data->private_data;
4546 bool use_compound_key = (hist_data->n_keys > 1);
4547 unsigned long entries[HIST_STACKTRACE_DEPTH];
4548 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
4549 char compound_key[HIST_KEY_SIZE_MAX];
4550 struct tracing_map_elt *elt = NULL;
4551 struct hist_field *key_field;
4552 u64 field_contents;
4553 void *key = NULL;
4554 unsigned int i;
4555
4556 memset(compound_key, 0, hist_data->key_size);
4557
4558 for_each_hist_key_field(i, hist_data) {
4559 key_field = hist_data->fields[i];
4560
4561 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4562 memset(entries, 0, HIST_STACKTRACE_SIZE);
4563 stack_trace_save(entries, HIST_STACKTRACE_DEPTH,
4564 HIST_STACKTRACE_SKIP);
4565 key = entries;
4566 } else {
4567 field_contents = key_field->fn(key_field, elt, rbe, rec);
4568 if (key_field->flags & HIST_FIELD_FL_STRING) {
4569 key = (void *)(unsigned long)field_contents;
4570 use_compound_key = true;
4571 } else
4572 key = (void *)&field_contents;
4573 }
4574
4575 if (use_compound_key)
4576 add_to_key(compound_key, key, key_field, rec);
4577 }
4578
4579 if (use_compound_key)
4580 key = compound_key;
4581
4582 if (hist_data->n_var_refs &&
4583 !resolve_var_refs(hist_data, key, var_ref_vals, false))
4584 return;
4585
4586 elt = tracing_map_insert(hist_data->map, key);
4587 if (!elt)
4588 return;
4589
4590 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
4591
4592 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
4593 hist_trigger_actions(hist_data, elt, rec, rbe, key, var_ref_vals);
4594 }
4595
hist_trigger_stacktrace_print(struct seq_file * m,unsigned long * stacktrace_entries,unsigned int max_entries)4596 static void hist_trigger_stacktrace_print(struct seq_file *m,
4597 unsigned long *stacktrace_entries,
4598 unsigned int max_entries)
4599 {
4600 char str[KSYM_SYMBOL_LEN];
4601 unsigned int spaces = 8;
4602 unsigned int i;
4603
4604 for (i = 0; i < max_entries; i++) {
4605 if (!stacktrace_entries[i])
4606 return;
4607
4608 seq_printf(m, "%*c", 1 + spaces, ' ');
4609 sprint_symbol(str, stacktrace_entries[i]);
4610 seq_printf(m, "%s\n", str);
4611 }
4612 }
4613
hist_trigger_print_key(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)4614 static void hist_trigger_print_key(struct seq_file *m,
4615 struct hist_trigger_data *hist_data,
4616 void *key,
4617 struct tracing_map_elt *elt)
4618 {
4619 struct hist_field *key_field;
4620 char str[KSYM_SYMBOL_LEN];
4621 bool multiline = false;
4622 const char *field_name;
4623 unsigned int i;
4624 u64 uval;
4625
4626 seq_puts(m, "{ ");
4627
4628 for_each_hist_key_field(i, hist_data) {
4629 key_field = hist_data->fields[i];
4630
4631 if (i > hist_data->n_vals)
4632 seq_puts(m, ", ");
4633
4634 field_name = hist_field_name(key_field, 0);
4635
4636 if (key_field->flags & HIST_FIELD_FL_HEX) {
4637 uval = *(u64 *)(key + key_field->offset);
4638 seq_printf(m, "%s: %llx", field_name, uval);
4639 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
4640 uval = *(u64 *)(key + key_field->offset);
4641 sprint_symbol_no_offset(str, uval);
4642 seq_printf(m, "%s: [%llx] %-45s", field_name,
4643 uval, str);
4644 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
4645 uval = *(u64 *)(key + key_field->offset);
4646 sprint_symbol(str, uval);
4647 seq_printf(m, "%s: [%llx] %-55s", field_name,
4648 uval, str);
4649 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
4650 struct hist_elt_data *elt_data = elt->private_data;
4651 char *comm;
4652
4653 if (WARN_ON_ONCE(!elt_data))
4654 return;
4655
4656 comm = elt_data->comm;
4657
4658 uval = *(u64 *)(key + key_field->offset);
4659 seq_printf(m, "%s: %-16s[%10llu]", field_name,
4660 comm, uval);
4661 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
4662 const char *syscall_name;
4663
4664 uval = *(u64 *)(key + key_field->offset);
4665 syscall_name = get_syscall_name(uval);
4666 if (!syscall_name)
4667 syscall_name = "unknown_syscall";
4668
4669 seq_printf(m, "%s: %-30s[%3llu]", field_name,
4670 syscall_name, uval);
4671 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4672 seq_puts(m, "stacktrace:\n");
4673 hist_trigger_stacktrace_print(m,
4674 key + key_field->offset,
4675 HIST_STACKTRACE_DEPTH);
4676 multiline = true;
4677 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
4678 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
4679 *(u64 *)(key + key_field->offset));
4680 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
4681 seq_printf(m, "%s: %-50s", field_name,
4682 (char *)(key + key_field->offset));
4683 } else {
4684 uval = *(u64 *)(key + key_field->offset);
4685 seq_printf(m, "%s: %10llu", field_name, uval);
4686 }
4687 }
4688
4689 if (!multiline)
4690 seq_puts(m, " ");
4691
4692 seq_puts(m, "}");
4693 }
4694
hist_trigger_entry_print(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)4695 static void hist_trigger_entry_print(struct seq_file *m,
4696 struct hist_trigger_data *hist_data,
4697 void *key,
4698 struct tracing_map_elt *elt)
4699 {
4700 const char *field_name;
4701 unsigned int i;
4702
4703 hist_trigger_print_key(m, hist_data, key, elt);
4704
4705 seq_printf(m, " hitcount: %10llu",
4706 tracing_map_read_sum(elt, HITCOUNT_IDX));
4707
4708 for (i = 1; i < hist_data->n_vals; i++) {
4709 field_name = hist_field_name(hist_data->fields[i], 0);
4710
4711 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
4712 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
4713 continue;
4714
4715 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
4716 seq_printf(m, " %s: %10llx", field_name,
4717 tracing_map_read_sum(elt, i));
4718 } else {
4719 seq_printf(m, " %s: %10llu", field_name,
4720 tracing_map_read_sum(elt, i));
4721 }
4722 }
4723
4724 print_actions(m, hist_data, elt);
4725
4726 seq_puts(m, "\n");
4727 }
4728
print_entries(struct seq_file * m,struct hist_trigger_data * hist_data)4729 static int print_entries(struct seq_file *m,
4730 struct hist_trigger_data *hist_data)
4731 {
4732 struct tracing_map_sort_entry **sort_entries = NULL;
4733 struct tracing_map *map = hist_data->map;
4734 int i, n_entries;
4735
4736 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
4737 hist_data->n_sort_keys,
4738 &sort_entries);
4739 if (n_entries < 0)
4740 return n_entries;
4741
4742 for (i = 0; i < n_entries; i++)
4743 hist_trigger_entry_print(m, hist_data,
4744 sort_entries[i]->key,
4745 sort_entries[i]->elt);
4746
4747 tracing_map_destroy_sort_entries(sort_entries, n_entries);
4748
4749 return n_entries;
4750 }
4751
hist_trigger_show(struct seq_file * m,struct event_trigger_data * data,int n)4752 static void hist_trigger_show(struct seq_file *m,
4753 struct event_trigger_data *data, int n)
4754 {
4755 struct hist_trigger_data *hist_data;
4756 int n_entries;
4757
4758 if (n > 0)
4759 seq_puts(m, "\n\n");
4760
4761 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4762 data->ops->print(m, data->ops, data);
4763 seq_puts(m, "#\n\n");
4764
4765 hist_data = data->private_data;
4766 n_entries = print_entries(m, hist_data);
4767 if (n_entries < 0)
4768 n_entries = 0;
4769
4770 track_data_snapshot_print(m, hist_data);
4771
4772 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
4773 (u64)atomic64_read(&hist_data->map->hits),
4774 n_entries, (u64)atomic64_read(&hist_data->map->drops));
4775 }
4776
hist_show(struct seq_file * m,void * v)4777 static int hist_show(struct seq_file *m, void *v)
4778 {
4779 struct event_trigger_data *data;
4780 struct trace_event_file *event_file;
4781 int n = 0, ret = 0;
4782
4783 mutex_lock(&event_mutex);
4784
4785 event_file = event_file_data(m->private);
4786 if (unlikely(!event_file)) {
4787 ret = -ENODEV;
4788 goto out_unlock;
4789 }
4790
4791 list_for_each_entry(data, &event_file->triggers, list) {
4792 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
4793 hist_trigger_show(m, data, n++);
4794 }
4795
4796 out_unlock:
4797 mutex_unlock(&event_mutex);
4798
4799 return ret;
4800 }
4801
event_hist_open(struct inode * inode,struct file * file)4802 static int event_hist_open(struct inode *inode, struct file *file)
4803 {
4804 int ret;
4805
4806 ret = security_locked_down(LOCKDOWN_TRACEFS);
4807 if (ret)
4808 return ret;
4809
4810 return single_open(file, hist_show, file);
4811 }
4812
4813 const struct file_operations event_hist_fops = {
4814 .open = event_hist_open,
4815 .read = seq_read,
4816 .llseek = seq_lseek,
4817 .release = single_release,
4818 };
4819
4820 #ifdef CONFIG_HIST_TRIGGERS_DEBUG
hist_field_debug_show_flags(struct seq_file * m,unsigned long flags)4821 static void hist_field_debug_show_flags(struct seq_file *m,
4822 unsigned long flags)
4823 {
4824 seq_puts(m, " flags:\n");
4825
4826 if (flags & HIST_FIELD_FL_KEY)
4827 seq_puts(m, " HIST_FIELD_FL_KEY\n");
4828 else if (flags & HIST_FIELD_FL_HITCOUNT)
4829 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n");
4830 else if (flags & HIST_FIELD_FL_VAR)
4831 seq_puts(m, " HIST_FIELD_FL_VAR\n");
4832 else if (flags & HIST_FIELD_FL_VAR_REF)
4833 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n");
4834 else
4835 seq_puts(m, " VAL: normal u64 value\n");
4836
4837 if (flags & HIST_FIELD_FL_ALIAS)
4838 seq_puts(m, " HIST_FIELD_FL_ALIAS\n");
4839 }
4840
hist_field_debug_show(struct seq_file * m,struct hist_field * field,unsigned long flags)4841 static int hist_field_debug_show(struct seq_file *m,
4842 struct hist_field *field, unsigned long flags)
4843 {
4844 if ((field->flags & flags) != flags) {
4845 seq_printf(m, "ERROR: bad flags - %lx\n", flags);
4846 return -EINVAL;
4847 }
4848
4849 hist_field_debug_show_flags(m, field->flags);
4850 if (field->field)
4851 seq_printf(m, " ftrace_event_field name: %s\n",
4852 field->field->name);
4853
4854 if (field->flags & HIST_FIELD_FL_VAR) {
4855 seq_printf(m, " var.name: %s\n", field->var.name);
4856 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4857 field->var.idx);
4858 }
4859
4860 if (field->flags & HIST_FIELD_FL_ALIAS)
4861 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
4862 field->var_ref_idx);
4863
4864 if (field->flags & HIST_FIELD_FL_VAR_REF) {
4865 seq_printf(m, " name: %s\n", field->name);
4866 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4867 field->var.idx);
4868 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data);
4869 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
4870 field->var_ref_idx);
4871 if (field->system)
4872 seq_printf(m, " system: %s\n", field->system);
4873 if (field->event_name)
4874 seq_printf(m, " event_name: %s\n", field->event_name);
4875 }
4876
4877 seq_printf(m, " type: %s\n", field->type);
4878 seq_printf(m, " size: %u\n", field->size);
4879 seq_printf(m, " is_signed: %u\n", field->is_signed);
4880
4881 return 0;
4882 }
4883
field_var_debug_show(struct seq_file * m,struct field_var * field_var,unsigned int i,bool save_vars)4884 static int field_var_debug_show(struct seq_file *m,
4885 struct field_var *field_var, unsigned int i,
4886 bool save_vars)
4887 {
4888 const char *vars_name = save_vars ? "save_vars" : "field_vars";
4889 struct hist_field *field;
4890 int ret = 0;
4891
4892 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i);
4893
4894 field = field_var->var;
4895
4896 seq_printf(m, "\n %s[%d].var:\n", vars_name, i);
4897
4898 hist_field_debug_show_flags(m, field->flags);
4899 seq_printf(m, " var.name: %s\n", field->var.name);
4900 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4901 field->var.idx);
4902
4903 field = field_var->val;
4904
4905 seq_printf(m, "\n %s[%d].val:\n", vars_name, i);
4906 if (field->field)
4907 seq_printf(m, " ftrace_event_field name: %s\n",
4908 field->field->name);
4909 else {
4910 ret = -EINVAL;
4911 goto out;
4912 }
4913
4914 seq_printf(m, " type: %s\n", field->type);
4915 seq_printf(m, " size: %u\n", field->size);
4916 seq_printf(m, " is_signed: %u\n", field->is_signed);
4917 out:
4918 return ret;
4919 }
4920
hist_action_debug_show(struct seq_file * m,struct action_data * data,int i)4921 static int hist_action_debug_show(struct seq_file *m,
4922 struct action_data *data, int i)
4923 {
4924 int ret = 0;
4925
4926 if (data->handler == HANDLER_ONMAX ||
4927 data->handler == HANDLER_ONCHANGE) {
4928 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i);
4929 ret = hist_field_debug_show(m, data->track_data.var_ref,
4930 HIST_FIELD_FL_VAR_REF);
4931 if (ret)
4932 goto out;
4933
4934 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i);
4935 ret = hist_field_debug_show(m, data->track_data.track_var,
4936 HIST_FIELD_FL_VAR);
4937 if (ret)
4938 goto out;
4939 }
4940
4941 if (data->handler == HANDLER_ONMATCH) {
4942 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n",
4943 i, data->match_data.event_system);
4944 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n",
4945 i, data->match_data.event);
4946 }
4947 out:
4948 return ret;
4949 }
4950
hist_actions_debug_show(struct seq_file * m,struct hist_trigger_data * hist_data)4951 static int hist_actions_debug_show(struct seq_file *m,
4952 struct hist_trigger_data *hist_data)
4953 {
4954 int i, ret = 0;
4955
4956 if (hist_data->n_actions)
4957 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n");
4958
4959 for (i = 0; i < hist_data->n_actions; i++) {
4960 struct action_data *action = hist_data->actions[i];
4961
4962 ret = hist_action_debug_show(m, action, i);
4963 if (ret)
4964 goto out;
4965 }
4966
4967 if (hist_data->n_save_vars)
4968 seq_puts(m, "\n save action variables (save() params):\n");
4969
4970 for (i = 0; i < hist_data->n_save_vars; i++) {
4971 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true);
4972 if (ret)
4973 goto out;
4974 }
4975 out:
4976 return ret;
4977 }
4978
hist_trigger_debug_show(struct seq_file * m,struct event_trigger_data * data,int n)4979 static void hist_trigger_debug_show(struct seq_file *m,
4980 struct event_trigger_data *data, int n)
4981 {
4982 struct hist_trigger_data *hist_data;
4983 int i, ret;
4984
4985 if (n > 0)
4986 seq_puts(m, "\n\n");
4987
4988 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4989 data->ops->print(m, data->ops, data);
4990 seq_puts(m, "#\n\n");
4991
4992 hist_data = data->private_data;
4993
4994 seq_printf(m, "hist_data: %p\n\n", hist_data);
4995 seq_printf(m, " n_vals: %u\n", hist_data->n_vals);
4996 seq_printf(m, " n_keys: %u\n", hist_data->n_keys);
4997 seq_printf(m, " n_fields: %u\n", hist_data->n_fields);
4998
4999 seq_puts(m, "\n val fields:\n\n");
5000
5001 seq_puts(m, " hist_data->fields[0]:\n");
5002 ret = hist_field_debug_show(m, hist_data->fields[0],
5003 HIST_FIELD_FL_HITCOUNT);
5004 if (ret)
5005 return;
5006
5007 for (i = 1; i < hist_data->n_vals; i++) {
5008 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5009 ret = hist_field_debug_show(m, hist_data->fields[i], 0);
5010 if (ret)
5011 return;
5012 }
5013
5014 seq_puts(m, "\n key fields:\n");
5015
5016 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) {
5017 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5018 ret = hist_field_debug_show(m, hist_data->fields[i],
5019 HIST_FIELD_FL_KEY);
5020 if (ret)
5021 return;
5022 }
5023
5024 if (hist_data->n_var_refs)
5025 seq_puts(m, "\n variable reference fields:\n");
5026
5027 for (i = 0; i < hist_data->n_var_refs; i++) {
5028 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i);
5029 ret = hist_field_debug_show(m, hist_data->var_refs[i],
5030 HIST_FIELD_FL_VAR_REF);
5031 if (ret)
5032 return;
5033 }
5034
5035 if (hist_data->n_field_vars)
5036 seq_puts(m, "\n field variables:\n");
5037
5038 for (i = 0; i < hist_data->n_field_vars; i++) {
5039 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false);
5040 if (ret)
5041 return;
5042 }
5043
5044 ret = hist_actions_debug_show(m, hist_data);
5045 if (ret)
5046 return;
5047 }
5048
hist_debug_show(struct seq_file * m,void * v)5049 static int hist_debug_show(struct seq_file *m, void *v)
5050 {
5051 struct event_trigger_data *data;
5052 struct trace_event_file *event_file;
5053 int n = 0, ret = 0;
5054
5055 mutex_lock(&event_mutex);
5056
5057 event_file = event_file_data(m->private);
5058 if (unlikely(!event_file)) {
5059 ret = -ENODEV;
5060 goto out_unlock;
5061 }
5062
5063 list_for_each_entry(data, &event_file->triggers, list) {
5064 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5065 hist_trigger_debug_show(m, data, n++);
5066 }
5067
5068 out_unlock:
5069 mutex_unlock(&event_mutex);
5070
5071 return ret;
5072 }
5073
event_hist_debug_open(struct inode * inode,struct file * file)5074 static int event_hist_debug_open(struct inode *inode, struct file *file)
5075 {
5076 int ret;
5077
5078 ret = security_locked_down(LOCKDOWN_TRACEFS);
5079 if (ret)
5080 return ret;
5081
5082 return single_open(file, hist_debug_show, file);
5083 }
5084
5085 const struct file_operations event_hist_debug_fops = {
5086 .open = event_hist_debug_open,
5087 .read = seq_read,
5088 .llseek = seq_lseek,
5089 .release = single_release,
5090 };
5091 #endif
5092
hist_field_print(struct seq_file * m,struct hist_field * hist_field)5093 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
5094 {
5095 const char *field_name = hist_field_name(hist_field, 0);
5096
5097 if (hist_field->var.name)
5098 seq_printf(m, "%s=", hist_field->var.name);
5099
5100 if (hist_field->flags & HIST_FIELD_FL_CPU)
5101 seq_puts(m, "common_cpu");
5102 else if (field_name) {
5103 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
5104 hist_field->flags & HIST_FIELD_FL_ALIAS)
5105 seq_putc(m, '$');
5106 seq_printf(m, "%s", field_name);
5107 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
5108 seq_puts(m, "common_timestamp");
5109
5110 if (hist_field->flags) {
5111 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
5112 !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
5113 const char *flags = get_hist_field_flags(hist_field);
5114
5115 if (flags)
5116 seq_printf(m, ".%s", flags);
5117 }
5118 }
5119 }
5120
event_hist_trigger_print(struct seq_file * m,struct event_trigger_ops * ops,struct event_trigger_data * data)5121 static int event_hist_trigger_print(struct seq_file *m,
5122 struct event_trigger_ops *ops,
5123 struct event_trigger_data *data)
5124 {
5125 struct hist_trigger_data *hist_data = data->private_data;
5126 struct hist_field *field;
5127 bool have_var = false;
5128 unsigned int i;
5129
5130 seq_puts(m, "hist:");
5131
5132 if (data->name)
5133 seq_printf(m, "%s:", data->name);
5134
5135 seq_puts(m, "keys=");
5136
5137 for_each_hist_key_field(i, hist_data) {
5138 field = hist_data->fields[i];
5139
5140 if (i > hist_data->n_vals)
5141 seq_puts(m, ",");
5142
5143 if (field->flags & HIST_FIELD_FL_STACKTRACE)
5144 seq_puts(m, "stacktrace");
5145 else
5146 hist_field_print(m, field);
5147 }
5148
5149 seq_puts(m, ":vals=");
5150
5151 for_each_hist_val_field(i, hist_data) {
5152 field = hist_data->fields[i];
5153 if (field->flags & HIST_FIELD_FL_VAR) {
5154 have_var = true;
5155 continue;
5156 }
5157
5158 if (i == HITCOUNT_IDX)
5159 seq_puts(m, "hitcount");
5160 else {
5161 seq_puts(m, ",");
5162 hist_field_print(m, field);
5163 }
5164 }
5165
5166 if (have_var) {
5167 unsigned int n = 0;
5168
5169 seq_puts(m, ":");
5170
5171 for_each_hist_val_field(i, hist_data) {
5172 field = hist_data->fields[i];
5173
5174 if (field->flags & HIST_FIELD_FL_VAR) {
5175 if (n++)
5176 seq_puts(m, ",");
5177 hist_field_print(m, field);
5178 }
5179 }
5180 }
5181
5182 seq_puts(m, ":sort=");
5183
5184 for (i = 0; i < hist_data->n_sort_keys; i++) {
5185 struct tracing_map_sort_key *sort_key;
5186 unsigned int idx, first_key_idx;
5187
5188 /* skip VAR vals */
5189 first_key_idx = hist_data->n_vals - hist_data->n_vars;
5190
5191 sort_key = &hist_data->sort_keys[i];
5192 idx = sort_key->field_idx;
5193
5194 if (WARN_ON(idx >= HIST_FIELDS_MAX))
5195 return -EINVAL;
5196
5197 if (i > 0)
5198 seq_puts(m, ",");
5199
5200 if (idx == HITCOUNT_IDX)
5201 seq_puts(m, "hitcount");
5202 else {
5203 if (idx >= first_key_idx)
5204 idx += hist_data->n_vars;
5205 hist_field_print(m, hist_data->fields[idx]);
5206 }
5207
5208 if (sort_key->descending)
5209 seq_puts(m, ".descending");
5210 }
5211 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5212 if (hist_data->enable_timestamps)
5213 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5214
5215 print_actions_spec(m, hist_data);
5216
5217 if (data->filter_str)
5218 seq_printf(m, " if %s", data->filter_str);
5219
5220 if (data->paused)
5221 seq_puts(m, " [paused]");
5222 else
5223 seq_puts(m, " [active]");
5224
5225 seq_putc(m, '\n');
5226
5227 return 0;
5228 }
5229
event_hist_trigger_init(struct event_trigger_ops * ops,struct event_trigger_data * data)5230 static int event_hist_trigger_init(struct event_trigger_ops *ops,
5231 struct event_trigger_data *data)
5232 {
5233 struct hist_trigger_data *hist_data = data->private_data;
5234
5235 if (!data->ref && hist_data->attrs->name)
5236 save_named_trigger(hist_data->attrs->name, data);
5237
5238 data->ref++;
5239
5240 return 0;
5241 }
5242
unregister_field_var_hists(struct hist_trigger_data * hist_data)5243 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5244 {
5245 struct trace_event_file *file;
5246 unsigned int i;
5247 char *cmd;
5248 int ret;
5249
5250 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5251 file = hist_data->field_var_hists[i]->hist_data->event_file;
5252 cmd = hist_data->field_var_hists[i]->cmd;
5253 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
5254 "!hist", "hist", cmd);
5255 }
5256 }
5257
event_hist_trigger_free(struct event_trigger_ops * ops,struct event_trigger_data * data)5258 static void event_hist_trigger_free(struct event_trigger_ops *ops,
5259 struct event_trigger_data *data)
5260 {
5261 struct hist_trigger_data *hist_data = data->private_data;
5262
5263 if (WARN_ON_ONCE(data->ref <= 0))
5264 return;
5265
5266 data->ref--;
5267 if (!data->ref) {
5268 if (data->name)
5269 del_named_trigger(data);
5270
5271 trigger_data_free(data);
5272
5273 remove_hist_vars(hist_data);
5274
5275 unregister_field_var_hists(hist_data);
5276
5277 destroy_hist_data(hist_data);
5278 }
5279 }
5280
5281 static struct event_trigger_ops event_hist_trigger_ops = {
5282 .func = event_hist_trigger,
5283 .print = event_hist_trigger_print,
5284 .init = event_hist_trigger_init,
5285 .free = event_hist_trigger_free,
5286 };
5287
event_hist_trigger_named_init(struct event_trigger_ops * ops,struct event_trigger_data * data)5288 static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
5289 struct event_trigger_data *data)
5290 {
5291 data->ref++;
5292
5293 save_named_trigger(data->named_data->name, data);
5294
5295 event_hist_trigger_init(ops, data->named_data);
5296
5297 return 0;
5298 }
5299
event_hist_trigger_named_free(struct event_trigger_ops * ops,struct event_trigger_data * data)5300 static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
5301 struct event_trigger_data *data)
5302 {
5303 if (WARN_ON_ONCE(data->ref <= 0))
5304 return;
5305
5306 event_hist_trigger_free(ops, data->named_data);
5307
5308 data->ref--;
5309 if (!data->ref) {
5310 del_named_trigger(data);
5311 trigger_data_free(data);
5312 }
5313 }
5314
5315 static struct event_trigger_ops event_hist_trigger_named_ops = {
5316 .func = event_hist_trigger,
5317 .print = event_hist_trigger_print,
5318 .init = event_hist_trigger_named_init,
5319 .free = event_hist_trigger_named_free,
5320 };
5321
event_hist_get_trigger_ops(char * cmd,char * param)5322 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5323 char *param)
5324 {
5325 return &event_hist_trigger_ops;
5326 }
5327
hist_clear(struct event_trigger_data * data)5328 static void hist_clear(struct event_trigger_data *data)
5329 {
5330 struct hist_trigger_data *hist_data = data->private_data;
5331
5332 if (data->name)
5333 pause_named_trigger(data);
5334
5335 tracepoint_synchronize_unregister();
5336
5337 tracing_map_clear(hist_data->map);
5338
5339 if (data->name)
5340 unpause_named_trigger(data);
5341 }
5342
compatible_field(struct ftrace_event_field * field,struct ftrace_event_field * test_field)5343 static bool compatible_field(struct ftrace_event_field *field,
5344 struct ftrace_event_field *test_field)
5345 {
5346 if (field == test_field)
5347 return true;
5348 if (field == NULL || test_field == NULL)
5349 return false;
5350 if (strcmp(field->name, test_field->name) != 0)
5351 return false;
5352 if (strcmp(field->type, test_field->type) != 0)
5353 return false;
5354 if (field->size != test_field->size)
5355 return false;
5356 if (field->is_signed != test_field->is_signed)
5357 return false;
5358
5359 return true;
5360 }
5361
hist_trigger_match(struct event_trigger_data * data,struct event_trigger_data * data_test,struct event_trigger_data * named_data,bool ignore_filter)5362 static bool hist_trigger_match(struct event_trigger_data *data,
5363 struct event_trigger_data *data_test,
5364 struct event_trigger_data *named_data,
5365 bool ignore_filter)
5366 {
5367 struct tracing_map_sort_key *sort_key, *sort_key_test;
5368 struct hist_trigger_data *hist_data, *hist_data_test;
5369 struct hist_field *key_field, *key_field_test;
5370 unsigned int i;
5371
5372 if (named_data && (named_data != data_test) &&
5373 (named_data != data_test->named_data))
5374 return false;
5375
5376 if (!named_data && is_named_trigger(data_test))
5377 return false;
5378
5379 hist_data = data->private_data;
5380 hist_data_test = data_test->private_data;
5381
5382 if (hist_data->n_vals != hist_data_test->n_vals ||
5383 hist_data->n_fields != hist_data_test->n_fields ||
5384 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5385 return false;
5386
5387 if (!ignore_filter) {
5388 if ((data->filter_str && !data_test->filter_str) ||
5389 (!data->filter_str && data_test->filter_str))
5390 return false;
5391 }
5392
5393 for_each_hist_field(i, hist_data) {
5394 key_field = hist_data->fields[i];
5395 key_field_test = hist_data_test->fields[i];
5396
5397 if (key_field->flags != key_field_test->flags)
5398 return false;
5399 if (!compatible_field(key_field->field, key_field_test->field))
5400 return false;
5401 if (key_field->offset != key_field_test->offset)
5402 return false;
5403 if (key_field->size != key_field_test->size)
5404 return false;
5405 if (key_field->is_signed != key_field_test->is_signed)
5406 return false;
5407 if (!!key_field->var.name != !!key_field_test->var.name)
5408 return false;
5409 if (key_field->var.name &&
5410 strcmp(key_field->var.name, key_field_test->var.name) != 0)
5411 return false;
5412 }
5413
5414 for (i = 0; i < hist_data->n_sort_keys; i++) {
5415 sort_key = &hist_data->sort_keys[i];
5416 sort_key_test = &hist_data_test->sort_keys[i];
5417
5418 if (sort_key->field_idx != sort_key_test->field_idx ||
5419 sort_key->descending != sort_key_test->descending)
5420 return false;
5421 }
5422
5423 if (!ignore_filter && data->filter_str &&
5424 (strcmp(data->filter_str, data_test->filter_str) != 0))
5425 return false;
5426
5427 if (!actions_match(hist_data, hist_data_test))
5428 return false;
5429
5430 return true;
5431 }
5432
hist_register_trigger(char * glob,struct event_trigger_ops * ops,struct event_trigger_data * data,struct trace_event_file * file)5433 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
5434 struct event_trigger_data *data,
5435 struct trace_event_file *file)
5436 {
5437 struct hist_trigger_data *hist_data = data->private_data;
5438 struct event_trigger_data *test, *named_data = NULL;
5439 struct trace_array *tr = file->tr;
5440 int ret = 0;
5441
5442 if (hist_data->attrs->name) {
5443 named_data = find_named_trigger(hist_data->attrs->name);
5444 if (named_data) {
5445 if (!hist_trigger_match(data, named_data, named_data,
5446 true)) {
5447 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name));
5448 ret = -EINVAL;
5449 goto out;
5450 }
5451 }
5452 }
5453
5454 if (hist_data->attrs->name && !named_data)
5455 goto new;
5456
5457 lockdep_assert_held(&event_mutex);
5458
5459 list_for_each_entry(test, &file->triggers, list) {
5460 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5461 if (!hist_trigger_match(data, test, named_data, false))
5462 continue;
5463 if (hist_data->attrs->pause)
5464 test->paused = true;
5465 else if (hist_data->attrs->cont)
5466 test->paused = false;
5467 else if (hist_data->attrs->clear)
5468 hist_clear(test);
5469 else {
5470 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0);
5471 ret = -EEXIST;
5472 }
5473 goto out;
5474 }
5475 }
5476 new:
5477 if (hist_data->attrs->cont || hist_data->attrs->clear) {
5478 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0);
5479 ret = -ENOENT;
5480 goto out;
5481 }
5482
5483 if (hist_data->attrs->pause)
5484 data->paused = true;
5485
5486 if (named_data) {
5487 data->private_data = named_data->private_data;
5488 set_named_trigger_data(data, named_data);
5489 data->ops = &event_hist_trigger_named_ops;
5490 }
5491
5492 if (data->ops->init) {
5493 ret = data->ops->init(data->ops, data);
5494 if (ret < 0)
5495 goto out;
5496 }
5497
5498 if (hist_data->enable_timestamps) {
5499 char *clock = hist_data->attrs->clock;
5500
5501 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
5502 if (ret) {
5503 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock));
5504 goto out;
5505 }
5506
5507 tracing_set_time_stamp_abs(file->tr, true);
5508 }
5509
5510 if (named_data)
5511 destroy_hist_data(hist_data);
5512
5513 ret++;
5514 out:
5515 return ret;
5516 }
5517
hist_trigger_enable(struct event_trigger_data * data,struct trace_event_file * file)5518 static int hist_trigger_enable(struct event_trigger_data *data,
5519 struct trace_event_file *file)
5520 {
5521 int ret = 0;
5522
5523 list_add_tail_rcu(&data->list, &file->triggers);
5524
5525 update_cond_flag(file);
5526
5527 if (trace_event_trigger_enable_disable(file, 1) < 0) {
5528 list_del_rcu(&data->list);
5529 update_cond_flag(file);
5530 ret--;
5531 }
5532
5533 return ret;
5534 }
5535
have_hist_trigger_match(struct event_trigger_data * data,struct trace_event_file * file)5536 static bool have_hist_trigger_match(struct event_trigger_data *data,
5537 struct trace_event_file *file)
5538 {
5539 struct hist_trigger_data *hist_data = data->private_data;
5540 struct event_trigger_data *test, *named_data = NULL;
5541 bool match = false;
5542
5543 lockdep_assert_held(&event_mutex);
5544
5545 if (hist_data->attrs->name)
5546 named_data = find_named_trigger(hist_data->attrs->name);
5547
5548 list_for_each_entry(test, &file->triggers, list) {
5549 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5550 if (hist_trigger_match(data, test, named_data, false)) {
5551 match = true;
5552 break;
5553 }
5554 }
5555 }
5556
5557 return match;
5558 }
5559
hist_trigger_check_refs(struct event_trigger_data * data,struct trace_event_file * file)5560 static bool hist_trigger_check_refs(struct event_trigger_data *data,
5561 struct trace_event_file *file)
5562 {
5563 struct hist_trigger_data *hist_data = data->private_data;
5564 struct event_trigger_data *test, *named_data = NULL;
5565
5566 lockdep_assert_held(&event_mutex);
5567
5568 if (hist_data->attrs->name)
5569 named_data = find_named_trigger(hist_data->attrs->name);
5570
5571 list_for_each_entry(test, &file->triggers, list) {
5572 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5573 if (!hist_trigger_match(data, test, named_data, false))
5574 continue;
5575 hist_data = test->private_data;
5576 if (check_var_refs(hist_data))
5577 return true;
5578 break;
5579 }
5580 }
5581
5582 return false;
5583 }
5584
hist_unregister_trigger(char * glob,struct event_trigger_ops * ops,struct event_trigger_data * data,struct trace_event_file * file)5585 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
5586 struct event_trigger_data *data,
5587 struct trace_event_file *file)
5588 {
5589 struct hist_trigger_data *hist_data = data->private_data;
5590 struct event_trigger_data *test, *named_data = NULL;
5591 bool unregistered = false;
5592
5593 lockdep_assert_held(&event_mutex);
5594
5595 if (hist_data->attrs->name)
5596 named_data = find_named_trigger(hist_data->attrs->name);
5597
5598 list_for_each_entry(test, &file->triggers, list) {
5599 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5600 if (!hist_trigger_match(data, test, named_data, false))
5601 continue;
5602 unregistered = true;
5603 list_del_rcu(&test->list);
5604 trace_event_trigger_enable_disable(file, 0);
5605 update_cond_flag(file);
5606 break;
5607 }
5608 }
5609
5610 if (unregistered && test->ops->free)
5611 test->ops->free(test->ops, test);
5612
5613 if (hist_data->enable_timestamps) {
5614 if (!hist_data->remove || unregistered)
5615 tracing_set_time_stamp_abs(file->tr, false);
5616 }
5617 }
5618
hist_file_check_refs(struct trace_event_file * file)5619 static bool hist_file_check_refs(struct trace_event_file *file)
5620 {
5621 struct hist_trigger_data *hist_data;
5622 struct event_trigger_data *test;
5623
5624 lockdep_assert_held(&event_mutex);
5625
5626 list_for_each_entry(test, &file->triggers, list) {
5627 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5628 hist_data = test->private_data;
5629 if (check_var_refs(hist_data))
5630 return true;
5631 }
5632 }
5633
5634 return false;
5635 }
5636
hist_unreg_all(struct trace_event_file * file)5637 static void hist_unreg_all(struct trace_event_file *file)
5638 {
5639 struct event_trigger_data *test, *n;
5640 struct hist_trigger_data *hist_data;
5641 struct synth_event *se;
5642 const char *se_name;
5643
5644 lockdep_assert_held(&event_mutex);
5645
5646 if (hist_file_check_refs(file))
5647 return;
5648
5649 list_for_each_entry_safe(test, n, &file->triggers, list) {
5650 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5651 hist_data = test->private_data;
5652 list_del_rcu(&test->list);
5653 trace_event_trigger_enable_disable(file, 0);
5654
5655 se_name = trace_event_name(file->event_call);
5656 se = find_synth_event(se_name);
5657 if (se)
5658 se->ref--;
5659
5660 update_cond_flag(file);
5661 if (hist_data->enable_timestamps)
5662 tracing_set_time_stamp_abs(file->tr, false);
5663 if (test->ops->free)
5664 test->ops->free(test->ops, test);
5665 }
5666 }
5667 }
5668
event_hist_trigger_func(struct event_command * cmd_ops,struct trace_event_file * file,char * glob,char * cmd,char * param)5669 static int event_hist_trigger_func(struct event_command *cmd_ops,
5670 struct trace_event_file *file,
5671 char *glob, char *cmd, char *param)
5672 {
5673 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
5674 struct event_trigger_data *trigger_data;
5675 struct hist_trigger_attrs *attrs;
5676 struct event_trigger_ops *trigger_ops;
5677 struct hist_trigger_data *hist_data;
5678 struct synth_event *se;
5679 const char *se_name;
5680 bool remove = false;
5681 char *trigger, *p;
5682 int ret = 0;
5683
5684 lockdep_assert_held(&event_mutex);
5685
5686 if (glob && strlen(glob)) {
5687 hist_err_clear();
5688 last_cmd_set(file, param);
5689 }
5690
5691 if (!param)
5692 return -EINVAL;
5693
5694 if (glob[0] == '!')
5695 remove = true;
5696
5697 /*
5698 * separate the trigger from the filter (k:v [if filter])
5699 * allowing for whitespace in the trigger
5700 */
5701 p = trigger = param;
5702 do {
5703 p = strstr(p, "if");
5704 if (!p)
5705 break;
5706 if (p == param)
5707 return -EINVAL;
5708 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
5709 p++;
5710 continue;
5711 }
5712 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1)
5713 return -EINVAL;
5714 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
5715 p++;
5716 continue;
5717 }
5718 break;
5719 } while (p);
5720
5721 if (!p)
5722 param = NULL;
5723 else {
5724 *(p - 1) = '\0';
5725 param = strstrip(p);
5726 trigger = strstrip(trigger);
5727 }
5728
5729 attrs = parse_hist_trigger_attrs(file->tr, trigger);
5730 if (IS_ERR(attrs))
5731 return PTR_ERR(attrs);
5732
5733 if (attrs->map_bits)
5734 hist_trigger_bits = attrs->map_bits;
5735
5736 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
5737 if (IS_ERR(hist_data)) {
5738 destroy_hist_trigger_attrs(attrs);
5739 return PTR_ERR(hist_data);
5740 }
5741
5742 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
5743
5744 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
5745 if (!trigger_data) {
5746 ret = -ENOMEM;
5747 goto out_free;
5748 }
5749
5750 trigger_data->count = -1;
5751 trigger_data->ops = trigger_ops;
5752 trigger_data->cmd_ops = cmd_ops;
5753
5754 INIT_LIST_HEAD(&trigger_data->list);
5755 RCU_INIT_POINTER(trigger_data->filter, NULL);
5756
5757 trigger_data->private_data = hist_data;
5758
5759 /* if param is non-empty, it's supposed to be a filter */
5760 if (param && cmd_ops->set_filter) {
5761 ret = cmd_ops->set_filter(param, trigger_data, file);
5762 if (ret < 0)
5763 goto out_free;
5764 }
5765
5766 if (remove) {
5767 if (!have_hist_trigger_match(trigger_data, file))
5768 goto out_free;
5769
5770 if (hist_trigger_check_refs(trigger_data, file)) {
5771 ret = -EBUSY;
5772 goto out_free;
5773 }
5774
5775 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5776 se_name = trace_event_name(file->event_call);
5777 se = find_synth_event(se_name);
5778 if (se)
5779 se->ref--;
5780 ret = 0;
5781 goto out_free;
5782 }
5783
5784 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
5785 /*
5786 * The above returns on success the # of triggers registered,
5787 * but if it didn't register any it returns zero. Consider no
5788 * triggers registered a failure too.
5789 */
5790 if (!ret) {
5791 if (!(attrs->pause || attrs->cont || attrs->clear))
5792 ret = -ENOENT;
5793 goto out_free;
5794 } else if (ret < 0)
5795 goto out_free;
5796
5797 if (get_named_trigger_data(trigger_data))
5798 goto enable;
5799
5800 if (has_hist_vars(hist_data))
5801 save_hist_vars(hist_data);
5802
5803 ret = create_actions(hist_data);
5804 if (ret)
5805 goto out_unreg;
5806
5807 ret = tracing_map_init(hist_data->map);
5808 if (ret)
5809 goto out_unreg;
5810 enable:
5811 ret = hist_trigger_enable(trigger_data, file);
5812 if (ret)
5813 goto out_unreg;
5814
5815 se_name = trace_event_name(file->event_call);
5816 se = find_synth_event(se_name);
5817 if (se)
5818 se->ref++;
5819 /* Just return zero, not the number of registered triggers */
5820 ret = 0;
5821 out:
5822 if (ret == 0)
5823 hist_err_clear();
5824
5825 return ret;
5826 out_unreg:
5827 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5828 out_free:
5829 if (cmd_ops->set_filter)
5830 cmd_ops->set_filter(NULL, trigger_data, NULL);
5831
5832 remove_hist_vars(hist_data);
5833
5834 kfree(trigger_data);
5835
5836 destroy_hist_data(hist_data);
5837 goto out;
5838 }
5839
5840 static struct event_command trigger_hist_cmd = {
5841 .name = "hist",
5842 .trigger_type = ETT_EVENT_HIST,
5843 .flags = EVENT_CMD_FL_NEEDS_REC,
5844 .func = event_hist_trigger_func,
5845 .reg = hist_register_trigger,
5846 .unreg = hist_unregister_trigger,
5847 .unreg_all = hist_unreg_all,
5848 .get_trigger_ops = event_hist_get_trigger_ops,
5849 .set_filter = set_trigger_filter,
5850 };
5851
register_trigger_hist_cmd(void)5852 __init int register_trigger_hist_cmd(void)
5853 {
5854 int ret;
5855
5856 ret = register_event_command(&trigger_hist_cmd);
5857 WARN_ON(ret < 0);
5858
5859 return ret;
5860 }
5861
5862 static void
hist_enable_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * event)5863 hist_enable_trigger(struct event_trigger_data *data, void *rec,
5864 struct ring_buffer_event *event)
5865 {
5866 struct enable_trigger_data *enable_data = data->private_data;
5867 struct event_trigger_data *test;
5868
5869 list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
5870 lockdep_is_held(&event_mutex)) {
5871 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5872 if (enable_data->enable)
5873 test->paused = false;
5874 else
5875 test->paused = true;
5876 }
5877 }
5878 }
5879
5880 static void
hist_enable_count_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * event)5881 hist_enable_count_trigger(struct event_trigger_data *data, void *rec,
5882 struct ring_buffer_event *event)
5883 {
5884 if (!data->count)
5885 return;
5886
5887 if (data->count != -1)
5888 (data->count)--;
5889
5890 hist_enable_trigger(data, rec, event);
5891 }
5892
5893 static struct event_trigger_ops hist_enable_trigger_ops = {
5894 .func = hist_enable_trigger,
5895 .print = event_enable_trigger_print,
5896 .init = event_trigger_init,
5897 .free = event_enable_trigger_free,
5898 };
5899
5900 static struct event_trigger_ops hist_enable_count_trigger_ops = {
5901 .func = hist_enable_count_trigger,
5902 .print = event_enable_trigger_print,
5903 .init = event_trigger_init,
5904 .free = event_enable_trigger_free,
5905 };
5906
5907 static struct event_trigger_ops hist_disable_trigger_ops = {
5908 .func = hist_enable_trigger,
5909 .print = event_enable_trigger_print,
5910 .init = event_trigger_init,
5911 .free = event_enable_trigger_free,
5912 };
5913
5914 static struct event_trigger_ops hist_disable_count_trigger_ops = {
5915 .func = hist_enable_count_trigger,
5916 .print = event_enable_trigger_print,
5917 .init = event_trigger_init,
5918 .free = event_enable_trigger_free,
5919 };
5920
5921 static struct event_trigger_ops *
hist_enable_get_trigger_ops(char * cmd,char * param)5922 hist_enable_get_trigger_ops(char *cmd, char *param)
5923 {
5924 struct event_trigger_ops *ops;
5925 bool enable;
5926
5927 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
5928
5929 if (enable)
5930 ops = param ? &hist_enable_count_trigger_ops :
5931 &hist_enable_trigger_ops;
5932 else
5933 ops = param ? &hist_disable_count_trigger_ops :
5934 &hist_disable_trigger_ops;
5935
5936 return ops;
5937 }
5938
hist_enable_unreg_all(struct trace_event_file * file)5939 static void hist_enable_unreg_all(struct trace_event_file *file)
5940 {
5941 struct event_trigger_data *test, *n;
5942
5943 list_for_each_entry_safe(test, n, &file->triggers, list) {
5944 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
5945 list_del_rcu(&test->list);
5946 update_cond_flag(file);
5947 trace_event_trigger_enable_disable(file, 0);
5948 if (test->ops->free)
5949 test->ops->free(test->ops, test);
5950 }
5951 }
5952 }
5953
5954 static struct event_command trigger_hist_enable_cmd = {
5955 .name = ENABLE_HIST_STR,
5956 .trigger_type = ETT_HIST_ENABLE,
5957 .func = event_enable_trigger_func,
5958 .reg = event_enable_register_trigger,
5959 .unreg = event_enable_unregister_trigger,
5960 .unreg_all = hist_enable_unreg_all,
5961 .get_trigger_ops = hist_enable_get_trigger_ops,
5962 .set_filter = set_trigger_filter,
5963 };
5964
5965 static struct event_command trigger_hist_disable_cmd = {
5966 .name = DISABLE_HIST_STR,
5967 .trigger_type = ETT_HIST_ENABLE,
5968 .func = event_enable_trigger_func,
5969 .reg = event_enable_register_trigger,
5970 .unreg = event_enable_unregister_trigger,
5971 .unreg_all = hist_enable_unreg_all,
5972 .get_trigger_ops = hist_enable_get_trigger_ops,
5973 .set_filter = set_trigger_filter,
5974 };
5975
unregister_trigger_hist_enable_disable_cmds(void)5976 static __init void unregister_trigger_hist_enable_disable_cmds(void)
5977 {
5978 unregister_event_command(&trigger_hist_enable_cmd);
5979 unregister_event_command(&trigger_hist_disable_cmd);
5980 }
5981
register_trigger_hist_enable_disable_cmds(void)5982 __init int register_trigger_hist_enable_disable_cmds(void)
5983 {
5984 int ret;
5985
5986 ret = register_event_command(&trigger_hist_enable_cmd);
5987 if (WARN_ON(ret < 0))
5988 return ret;
5989 ret = register_event_command(&trigger_hist_disable_cmd);
5990 if (WARN_ON(ret < 0))
5991 unregister_trigger_hist_enable_disable_cmds();
5992
5993 return ret;
5994 }
5995