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 ref_field->system = NULL;
1793 kfree(ref_field->event_name);
1794 ref_field->event_name = NULL;
1795 kfree(ref_field->name);
1796 ref_field->name = NULL;
1797
1798 goto out;
1799 }
1800
find_var_ref_idx(struct hist_trigger_data * hist_data,struct hist_field * var_field)1801 static int find_var_ref_idx(struct hist_trigger_data *hist_data,
1802 struct hist_field *var_field)
1803 {
1804 struct hist_field *ref_field;
1805 int i;
1806
1807 for (i = 0; i < hist_data->n_var_refs; i++) {
1808 ref_field = hist_data->var_refs[i];
1809 if (ref_field->var.idx == var_field->var.idx &&
1810 ref_field->var.hist_data == var_field->hist_data)
1811 return i;
1812 }
1813
1814 return -ENOENT;
1815 }
1816
1817 /**
1818 * create_var_ref - Create a variable reference and attach it to trigger
1819 * @hist_data: The trigger that will be referencing the variable
1820 * @var_field: The VAR field to create a reference to
1821 * @system: The optional system string
1822 * @event_name: The optional event_name string
1823 *
1824 * Given a variable hist_field, create a VAR_REF hist_field that
1825 * represents a reference to it.
1826 *
1827 * This function also adds the reference to the trigger that
1828 * now references the variable.
1829 *
1830 * Return: The VAR_REF field if successful, NULL if not
1831 */
create_var_ref(struct hist_trigger_data * hist_data,struct hist_field * var_field,char * system,char * event_name)1832 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
1833 struct hist_field *var_field,
1834 char *system, char *event_name)
1835 {
1836 unsigned long flags = HIST_FIELD_FL_VAR_REF;
1837 struct hist_field *ref_field;
1838 int i;
1839
1840 /* Check if the variable already exists */
1841 for (i = 0; i < hist_data->n_var_refs; i++) {
1842 ref_field = hist_data->var_refs[i];
1843 if (ref_field->var.idx == var_field->var.idx &&
1844 ref_field->var.hist_data == var_field->hist_data) {
1845 get_hist_field(ref_field);
1846 return ref_field;
1847 }
1848 }
1849
1850 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
1851 if (ref_field) {
1852 if (init_var_ref(ref_field, var_field, system, event_name)) {
1853 destroy_hist_field(ref_field, 0);
1854 return NULL;
1855 }
1856
1857 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
1858 ref_field->var_ref_idx = hist_data->n_var_refs++;
1859 }
1860
1861 return ref_field;
1862 }
1863
is_var_ref(char * var_name)1864 static bool is_var_ref(char *var_name)
1865 {
1866 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
1867 return false;
1868
1869 return true;
1870 }
1871
field_name_from_var(struct hist_trigger_data * hist_data,char * var_name)1872 static char *field_name_from_var(struct hist_trigger_data *hist_data,
1873 char *var_name)
1874 {
1875 char *name, *field;
1876 unsigned int i;
1877
1878 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
1879 name = hist_data->attrs->var_defs.name[i];
1880
1881 if (strcmp(var_name, name) == 0) {
1882 field = hist_data->attrs->var_defs.expr[i];
1883 if (contains_operator(field) || is_var_ref(field))
1884 continue;
1885 return field;
1886 }
1887 }
1888
1889 return NULL;
1890 }
1891
local_field_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)1892 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
1893 char *system, char *event_name,
1894 char *var_name)
1895 {
1896 struct trace_event_call *call;
1897
1898 if (system && event_name) {
1899 call = hist_data->event_file->event_call;
1900
1901 if (strcmp(system, call->class->system) != 0)
1902 return NULL;
1903
1904 if (strcmp(event_name, trace_event_name(call)) != 0)
1905 return NULL;
1906 }
1907
1908 if (!!system != !!event_name)
1909 return NULL;
1910
1911 if (!is_var_ref(var_name))
1912 return NULL;
1913
1914 var_name++;
1915
1916 return field_name_from_var(hist_data, var_name);
1917 }
1918
parse_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)1919 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
1920 char *system, char *event_name,
1921 char *var_name)
1922 {
1923 struct hist_field *var_field = NULL, *ref_field = NULL;
1924 struct trace_array *tr = hist_data->event_file->tr;
1925
1926 if (!is_var_ref(var_name))
1927 return NULL;
1928
1929 var_name++;
1930
1931 var_field = find_event_var(hist_data, system, event_name, var_name);
1932 if (var_field)
1933 ref_field = create_var_ref(hist_data, var_field,
1934 system, event_name);
1935
1936 if (!ref_field)
1937 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name));
1938
1939 return ref_field;
1940 }
1941
1942 static struct ftrace_event_field *
parse_field(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_str,unsigned long * flags)1943 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
1944 char *field_str, unsigned long *flags)
1945 {
1946 struct ftrace_event_field *field = NULL;
1947 char *field_name, *modifier, *str;
1948 struct trace_array *tr = file->tr;
1949
1950 modifier = str = kstrdup(field_str, GFP_KERNEL);
1951 if (!modifier)
1952 return ERR_PTR(-ENOMEM);
1953
1954 field_name = strsep(&modifier, ".");
1955 if (modifier) {
1956 if (strcmp(modifier, "hex") == 0)
1957 *flags |= HIST_FIELD_FL_HEX;
1958 else if (strcmp(modifier, "sym") == 0)
1959 *flags |= HIST_FIELD_FL_SYM;
1960 else if (strcmp(modifier, "sym-offset") == 0)
1961 *flags |= HIST_FIELD_FL_SYM_OFFSET;
1962 else if ((strcmp(modifier, "execname") == 0) &&
1963 (strcmp(field_name, "common_pid") == 0))
1964 *flags |= HIST_FIELD_FL_EXECNAME;
1965 else if (strcmp(modifier, "syscall") == 0)
1966 *flags |= HIST_FIELD_FL_SYSCALL;
1967 else if (strcmp(modifier, "log2") == 0)
1968 *flags |= HIST_FIELD_FL_LOG2;
1969 else if (strcmp(modifier, "usecs") == 0)
1970 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
1971 else {
1972 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
1973 field = ERR_PTR(-EINVAL);
1974 goto out;
1975 }
1976 }
1977
1978 if (strcmp(field_name, "common_timestamp") == 0) {
1979 *flags |= HIST_FIELD_FL_TIMESTAMP;
1980 hist_data->enable_timestamps = true;
1981 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1982 hist_data->attrs->ts_in_usecs = true;
1983 } else if (strcmp(field_name, "common_cpu") == 0)
1984 *flags |= HIST_FIELD_FL_CPU;
1985 else {
1986 field = trace_find_event_field(file->event_call, field_name);
1987 if (!field || !field->size) {
1988 /*
1989 * For backward compatibility, if field_name
1990 * was "cpu", then we treat this the same as
1991 * common_cpu. This also works for "CPU".
1992 */
1993 if (field && field->filter_type == FILTER_CPU) {
1994 *flags |= HIST_FIELD_FL_CPU;
1995 } else {
1996 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND,
1997 errpos(field_name));
1998 field = ERR_PTR(-EINVAL);
1999 goto out;
2000 }
2001 }
2002 }
2003 out:
2004 kfree(str);
2005
2006 return field;
2007 }
2008
create_alias(struct hist_trigger_data * hist_data,struct hist_field * var_ref,char * var_name)2009 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2010 struct hist_field *var_ref,
2011 char *var_name)
2012 {
2013 struct hist_field *alias = NULL;
2014 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2015
2016 alias = create_hist_field(hist_data, NULL, flags, var_name);
2017 if (!alias)
2018 return NULL;
2019
2020 alias->fn = var_ref->fn;
2021 alias->operands[0] = var_ref;
2022
2023 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2024 destroy_hist_field(alias, 0);
2025 return NULL;
2026 }
2027
2028 alias->var_ref_idx = var_ref->var_ref_idx;
2029
2030 return alias;
2031 }
2032
parse_atom(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long * flags,char * var_name)2033 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2034 struct trace_event_file *file, char *str,
2035 unsigned long *flags, char *var_name)
2036 {
2037 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2038 struct ftrace_event_field *field = NULL;
2039 struct hist_field *hist_field = NULL;
2040 int ret = 0;
2041
2042 s = strchr(str, '.');
2043 if (s) {
2044 s = strchr(++s, '.');
2045 if (s) {
2046 ref_system = strsep(&str, ".");
2047 if (!str) {
2048 ret = -EINVAL;
2049 goto out;
2050 }
2051 ref_event = strsep(&str, ".");
2052 if (!str) {
2053 ret = -EINVAL;
2054 goto out;
2055 }
2056 ref_var = str;
2057 }
2058 }
2059
2060 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2061 if (!s) {
2062 hist_field = parse_var_ref(hist_data, ref_system,
2063 ref_event, ref_var);
2064 if (hist_field) {
2065 if (var_name) {
2066 hist_field = create_alias(hist_data, hist_field, var_name);
2067 if (!hist_field) {
2068 ret = -ENOMEM;
2069 goto out;
2070 }
2071 }
2072 return hist_field;
2073 }
2074 } else
2075 str = s;
2076
2077 field = parse_field(hist_data, file, str, flags);
2078 if (IS_ERR(field)) {
2079 ret = PTR_ERR(field);
2080 goto out;
2081 }
2082
2083 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2084 if (!hist_field) {
2085 ret = -ENOMEM;
2086 goto out;
2087 }
2088
2089 return hist_field;
2090 out:
2091 return ERR_PTR(ret);
2092 }
2093
2094 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2095 struct trace_event_file *file,
2096 char *str, unsigned long flags,
2097 char *var_name, unsigned int level);
2098
parse_unary(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int level)2099 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2100 struct trace_event_file *file,
2101 char *str, unsigned long flags,
2102 char *var_name, unsigned int level)
2103 {
2104 struct hist_field *operand1, *expr = NULL;
2105 unsigned long operand_flags;
2106 int ret = 0;
2107 char *s;
2108
2109 /* we support only -(xxx) i.e. explicit parens required */
2110
2111 if (level > 3) {
2112 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2113 ret = -EINVAL;
2114 goto free;
2115 }
2116
2117 str++; /* skip leading '-' */
2118
2119 s = strchr(str, '(');
2120 if (s)
2121 str++;
2122 else {
2123 ret = -EINVAL;
2124 goto free;
2125 }
2126
2127 s = strrchr(str, ')');
2128 if (s)
2129 *s = '\0';
2130 else {
2131 ret = -EINVAL; /* no closing ')' */
2132 goto free;
2133 }
2134
2135 flags |= HIST_FIELD_FL_EXPR;
2136 expr = create_hist_field(hist_data, NULL, flags, var_name);
2137 if (!expr) {
2138 ret = -ENOMEM;
2139 goto free;
2140 }
2141
2142 operand_flags = 0;
2143 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2144 if (IS_ERR(operand1)) {
2145 ret = PTR_ERR(operand1);
2146 goto free;
2147 }
2148 if (operand1->flags & HIST_FIELD_FL_STRING) {
2149 /* String type can not be the operand of unary operator. */
2150 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2151 destroy_hist_field(operand1, 0);
2152 ret = -EINVAL;
2153 goto free;
2154 }
2155
2156 expr->flags |= operand1->flags &
2157 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2158 expr->fn = hist_field_unary_minus;
2159 expr->operands[0] = operand1;
2160 expr->size = operand1->size;
2161 expr->is_signed = operand1->is_signed;
2162 expr->operator = FIELD_OP_UNARY_MINUS;
2163 expr->name = expr_str(expr, 0);
2164 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2165 if (!expr->type) {
2166 ret = -ENOMEM;
2167 goto free;
2168 }
2169
2170 return expr;
2171 free:
2172 destroy_hist_field(expr, 0);
2173 return ERR_PTR(ret);
2174 }
2175
check_expr_operands(struct trace_array * tr,struct hist_field * operand1,struct hist_field * operand2)2176 static int check_expr_operands(struct trace_array *tr,
2177 struct hist_field *operand1,
2178 struct hist_field *operand2)
2179 {
2180 unsigned long operand1_flags = operand1->flags;
2181 unsigned long operand2_flags = operand2->flags;
2182
2183 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2184 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2185 struct hist_field *var;
2186
2187 var = find_var_field(operand1->var.hist_data, operand1->name);
2188 if (!var)
2189 return -EINVAL;
2190 operand1_flags = var->flags;
2191 }
2192
2193 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2194 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2195 struct hist_field *var;
2196
2197 var = find_var_field(operand2->var.hist_data, operand2->name);
2198 if (!var)
2199 return -EINVAL;
2200 operand2_flags = var->flags;
2201 }
2202
2203 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2204 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2205 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0);
2206 return -EINVAL;
2207 }
2208
2209 return 0;
2210 }
2211
parse_expr(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int level)2212 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2213 struct trace_event_file *file,
2214 char *str, unsigned long flags,
2215 char *var_name, unsigned int level)
2216 {
2217 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2218 unsigned long operand_flags;
2219 int field_op, ret = -EINVAL;
2220 char *sep, *operand1_str;
2221
2222 if (level > 3) {
2223 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2224 return ERR_PTR(-EINVAL);
2225 }
2226
2227 field_op = contains_operator(str);
2228
2229 if (field_op == FIELD_OP_NONE)
2230 return parse_atom(hist_data, file, str, &flags, var_name);
2231
2232 if (field_op == FIELD_OP_UNARY_MINUS)
2233 return parse_unary(hist_data, file, str, flags, var_name, ++level);
2234
2235 switch (field_op) {
2236 case FIELD_OP_MINUS:
2237 sep = "-";
2238 break;
2239 case FIELD_OP_PLUS:
2240 sep = "+";
2241 break;
2242 default:
2243 goto free;
2244 }
2245
2246 operand1_str = strsep(&str, sep);
2247 if (!operand1_str || !str)
2248 goto free;
2249
2250 operand_flags = 0;
2251 operand1 = parse_atom(hist_data, file, operand1_str,
2252 &operand_flags, NULL);
2253 if (IS_ERR(operand1)) {
2254 ret = PTR_ERR(operand1);
2255 operand1 = NULL;
2256 goto free;
2257 }
2258 if (operand1->flags & HIST_FIELD_FL_STRING) {
2259 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str));
2260 ret = -EINVAL;
2261 goto free;
2262 }
2263
2264 /* rest of string could be another expression e.g. b+c in a+b+c */
2265 operand_flags = 0;
2266 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2267 if (IS_ERR(operand2)) {
2268 ret = PTR_ERR(operand2);
2269 operand2 = NULL;
2270 goto free;
2271 }
2272 if (operand2->flags & HIST_FIELD_FL_STRING) {
2273 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2274 ret = -EINVAL;
2275 goto free;
2276 }
2277
2278 ret = check_expr_operands(file->tr, operand1, operand2);
2279 if (ret)
2280 goto free;
2281
2282 flags |= HIST_FIELD_FL_EXPR;
2283
2284 flags |= operand1->flags &
2285 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2286
2287 expr = create_hist_field(hist_data, NULL, flags, var_name);
2288 if (!expr) {
2289 ret = -ENOMEM;
2290 goto free;
2291 }
2292
2293 operand1->read_once = true;
2294 operand2->read_once = true;
2295
2296 expr->operands[0] = operand1;
2297 expr->operands[1] = operand2;
2298
2299 /* The operand sizes should be the same, so just pick one */
2300 expr->size = operand1->size;
2301 expr->is_signed = operand1->is_signed;
2302
2303 expr->operator = field_op;
2304 expr->name = expr_str(expr, 0);
2305 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2306 if (!expr->type) {
2307 ret = -ENOMEM;
2308 goto free;
2309 }
2310
2311 switch (field_op) {
2312 case FIELD_OP_MINUS:
2313 expr->fn = hist_field_minus;
2314 break;
2315 case FIELD_OP_PLUS:
2316 expr->fn = hist_field_plus;
2317 break;
2318 default:
2319 ret = -EINVAL;
2320 goto free;
2321 }
2322
2323 return expr;
2324 free:
2325 destroy_hist_field(operand1, 0);
2326 destroy_hist_field(operand2, 0);
2327 destroy_hist_field(expr, 0);
2328
2329 return ERR_PTR(ret);
2330 }
2331
find_trigger_filter(struct hist_trigger_data * hist_data,struct trace_event_file * file)2332 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2333 struct trace_event_file *file)
2334 {
2335 struct event_trigger_data *test;
2336
2337 lockdep_assert_held(&event_mutex);
2338
2339 list_for_each_entry(test, &file->triggers, list) {
2340 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2341 if (test->private_data == hist_data)
2342 return test->filter_str;
2343 }
2344 }
2345
2346 return NULL;
2347 }
2348
2349 static struct event_command trigger_hist_cmd;
2350 static int event_hist_trigger_func(struct event_command *cmd_ops,
2351 struct trace_event_file *file,
2352 char *glob, char *cmd, char *param);
2353
compatible_keys(struct hist_trigger_data * target_hist_data,struct hist_trigger_data * hist_data,unsigned int n_keys)2354 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2355 struct hist_trigger_data *hist_data,
2356 unsigned int n_keys)
2357 {
2358 struct hist_field *target_hist_field, *hist_field;
2359 unsigned int n, i, j;
2360
2361 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2362 return false;
2363
2364 i = hist_data->n_vals;
2365 j = target_hist_data->n_vals;
2366
2367 for (n = 0; n < n_keys; n++) {
2368 hist_field = hist_data->fields[i + n];
2369 target_hist_field = target_hist_data->fields[j + n];
2370
2371 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2372 return false;
2373 if (hist_field->size != target_hist_field->size)
2374 return false;
2375 if (hist_field->is_signed != target_hist_field->is_signed)
2376 return false;
2377 }
2378
2379 return true;
2380 }
2381
2382 static struct hist_trigger_data *
find_compatible_hist(struct hist_trigger_data * target_hist_data,struct trace_event_file * file)2383 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2384 struct trace_event_file *file)
2385 {
2386 struct hist_trigger_data *hist_data;
2387 struct event_trigger_data *test;
2388 unsigned int n_keys;
2389
2390 lockdep_assert_held(&event_mutex);
2391
2392 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2393
2394 list_for_each_entry(test, &file->triggers, list) {
2395 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2396 hist_data = test->private_data;
2397
2398 if (compatible_keys(target_hist_data, hist_data, n_keys))
2399 return hist_data;
2400 }
2401 }
2402
2403 return NULL;
2404 }
2405
event_file(struct trace_array * tr,char * system,char * event_name)2406 static struct trace_event_file *event_file(struct trace_array *tr,
2407 char *system, char *event_name)
2408 {
2409 struct trace_event_file *file;
2410
2411 file = __find_event_file(tr, system, event_name);
2412 if (!file)
2413 return ERR_PTR(-EINVAL);
2414
2415 return file;
2416 }
2417
2418 static struct hist_field *
find_synthetic_field_var(struct hist_trigger_data * target_hist_data,char * system,char * event_name,char * field_name)2419 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2420 char *system, char *event_name, char *field_name)
2421 {
2422 struct hist_field *event_var;
2423 char *synthetic_name;
2424
2425 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2426 if (!synthetic_name)
2427 return ERR_PTR(-ENOMEM);
2428
2429 strcpy(synthetic_name, "synthetic_");
2430 strcat(synthetic_name, field_name);
2431
2432 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2433
2434 kfree(synthetic_name);
2435
2436 return event_var;
2437 }
2438
2439 /**
2440 * create_field_var_hist - Automatically create a histogram and var for a field
2441 * @target_hist_data: The target hist trigger
2442 * @subsys_name: Optional subsystem name
2443 * @event_name: Optional event name
2444 * @field_name: The name of the field (and the resulting variable)
2445 *
2446 * Hist trigger actions fetch data from variables, not directly from
2447 * events. However, for convenience, users are allowed to directly
2448 * specify an event field in an action, which will be automatically
2449 * converted into a variable on their behalf.
2450
2451 * If a user specifies a field on an event that isn't the event the
2452 * histogram currently being defined (the target event histogram), the
2453 * only way that can be accomplished is if a new hist trigger is
2454 * created and the field variable defined on that.
2455 *
2456 * This function creates a new histogram compatible with the target
2457 * event (meaning a histogram with the same key as the target
2458 * histogram), and creates a variable for the specified field, but
2459 * with 'synthetic_' prepended to the variable name in order to avoid
2460 * collision with normal field variables.
2461 *
2462 * Return: The variable created for the field.
2463 */
2464 static struct hist_field *
create_field_var_hist(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * field_name)2465 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2466 char *subsys_name, char *event_name, char *field_name)
2467 {
2468 struct trace_array *tr = target_hist_data->event_file->tr;
2469 struct hist_field *event_var = ERR_PTR(-EINVAL);
2470 struct hist_trigger_data *hist_data;
2471 unsigned int i, n, first = true;
2472 struct field_var_hist *var_hist;
2473 struct trace_event_file *file;
2474 struct hist_field *key_field;
2475 char *saved_filter;
2476 char *cmd;
2477 int ret;
2478
2479 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2480 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2481 return ERR_PTR(-EINVAL);
2482 }
2483
2484 file = event_file(tr, subsys_name, event_name);
2485
2486 if (IS_ERR(file)) {
2487 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name));
2488 ret = PTR_ERR(file);
2489 return ERR_PTR(ret);
2490 }
2491
2492 /*
2493 * Look for a histogram compatible with target. We'll use the
2494 * found histogram specification to create a new matching
2495 * histogram with our variable on it. target_hist_data is not
2496 * yet a registered histogram so we can't use that.
2497 */
2498 hist_data = find_compatible_hist(target_hist_data, file);
2499 if (!hist_data) {
2500 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name));
2501 return ERR_PTR(-EINVAL);
2502 }
2503
2504 /* See if a synthetic field variable has already been created */
2505 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2506 event_name, field_name);
2507 if (!IS_ERR_OR_NULL(event_var))
2508 return event_var;
2509
2510 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2511 if (!var_hist)
2512 return ERR_PTR(-ENOMEM);
2513
2514 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2515 if (!cmd) {
2516 kfree(var_hist);
2517 return ERR_PTR(-ENOMEM);
2518 }
2519
2520 /* Use the same keys as the compatible histogram */
2521 strcat(cmd, "keys=");
2522
2523 for_each_hist_key_field(i, hist_data) {
2524 key_field = hist_data->fields[i];
2525 if (!first)
2526 strcat(cmd, ",");
2527 strcat(cmd, key_field->field->name);
2528 first = false;
2529 }
2530
2531 /* Create the synthetic field variable specification */
2532 strcat(cmd, ":synthetic_");
2533 strcat(cmd, field_name);
2534 strcat(cmd, "=");
2535 strcat(cmd, field_name);
2536
2537 /* Use the same filter as the compatible histogram */
2538 saved_filter = find_trigger_filter(hist_data, file);
2539 if (saved_filter) {
2540 strcat(cmd, " if ");
2541 strcat(cmd, saved_filter);
2542 }
2543
2544 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
2545 if (!var_hist->cmd) {
2546 kfree(cmd);
2547 kfree(var_hist);
2548 return ERR_PTR(-ENOMEM);
2549 }
2550
2551 /* Save the compatible histogram information */
2552 var_hist->hist_data = hist_data;
2553
2554 /* Create the new histogram with our variable */
2555 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
2556 "", "hist", cmd);
2557 if (ret) {
2558 kfree(cmd);
2559 kfree(var_hist->cmd);
2560 kfree(var_hist);
2561 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name));
2562 return ERR_PTR(ret);
2563 }
2564
2565 kfree(cmd);
2566
2567 /* If we can't find the variable, something went wrong */
2568 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2569 event_name, field_name);
2570 if (IS_ERR_OR_NULL(event_var)) {
2571 kfree(var_hist->cmd);
2572 kfree(var_hist);
2573 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name));
2574 return ERR_PTR(-EINVAL);
2575 }
2576
2577 n = target_hist_data->n_field_var_hists;
2578 target_hist_data->field_var_hists[n] = var_hist;
2579 target_hist_data->n_field_var_hists++;
2580
2581 return event_var;
2582 }
2583
2584 static struct hist_field *
find_target_event_var(struct hist_trigger_data * hist_data,char * subsys_name,char * event_name,char * var_name)2585 find_target_event_var(struct hist_trigger_data *hist_data,
2586 char *subsys_name, char *event_name, char *var_name)
2587 {
2588 struct trace_event_file *file = hist_data->event_file;
2589 struct hist_field *hist_field = NULL;
2590
2591 if (subsys_name) {
2592 struct trace_event_call *call;
2593
2594 if (!event_name)
2595 return NULL;
2596
2597 call = file->event_call;
2598
2599 if (strcmp(subsys_name, call->class->system) != 0)
2600 return NULL;
2601
2602 if (strcmp(event_name, trace_event_name(call)) != 0)
2603 return NULL;
2604 }
2605
2606 hist_field = find_var_field(hist_data, var_name);
2607
2608 return hist_field;
2609 }
2610
__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)2611 static inline void __update_field_vars(struct tracing_map_elt *elt,
2612 struct ring_buffer_event *rbe,
2613 void *rec,
2614 struct field_var **field_vars,
2615 unsigned int n_field_vars,
2616 unsigned int field_var_str_start)
2617 {
2618 struct hist_elt_data *elt_data = elt->private_data;
2619 unsigned int i, j, var_idx;
2620 u64 var_val;
2621
2622 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
2623 struct field_var *field_var = field_vars[i];
2624 struct hist_field *var = field_var->var;
2625 struct hist_field *val = field_var->val;
2626
2627 var_val = val->fn(val, elt, rbe, rec);
2628 var_idx = var->var.idx;
2629
2630 if (val->flags & HIST_FIELD_FL_STRING) {
2631 char *str = elt_data->field_var_str[j++];
2632 char *val_str = (char *)(uintptr_t)var_val;
2633 unsigned int size;
2634
2635 size = min(val->size, STR_VAR_LEN_MAX);
2636 strscpy(str, val_str, size);
2637 var_val = (u64)(uintptr_t)str;
2638 }
2639 tracing_map_set_var(elt, var_idx, var_val);
2640 }
2641 }
2642
update_field_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * rec)2643 static void update_field_vars(struct hist_trigger_data *hist_data,
2644 struct tracing_map_elt *elt,
2645 struct ring_buffer_event *rbe,
2646 void *rec)
2647 {
2648 __update_field_vars(elt, rbe, rec, hist_data->field_vars,
2649 hist_data->n_field_vars, 0);
2650 }
2651
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)2652 static void save_track_data_vars(struct hist_trigger_data *hist_data,
2653 struct tracing_map_elt *elt, void *rec,
2654 struct ring_buffer_event *rbe, void *key,
2655 struct action_data *data, u64 *var_ref_vals)
2656 {
2657 __update_field_vars(elt, rbe, rec, hist_data->save_vars,
2658 hist_data->n_save_vars, hist_data->n_field_var_str);
2659 }
2660
create_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * name,int size,const char * type)2661 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
2662 struct trace_event_file *file,
2663 char *name, int size, const char *type)
2664 {
2665 struct hist_field *var;
2666 int idx;
2667
2668 if (find_var(hist_data, file, name) && !hist_data->remove) {
2669 var = ERR_PTR(-EINVAL);
2670 goto out;
2671 }
2672
2673 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
2674 if (!var) {
2675 var = ERR_PTR(-ENOMEM);
2676 goto out;
2677 }
2678
2679 idx = tracing_map_add_var(hist_data->map);
2680 if (idx < 0) {
2681 kfree(var);
2682 var = ERR_PTR(-EINVAL);
2683 goto out;
2684 }
2685
2686 var->ref = 1;
2687 var->flags = HIST_FIELD_FL_VAR;
2688 var->var.idx = idx;
2689 var->var.hist_data = var->hist_data = hist_data;
2690 var->size = size;
2691 var->var.name = kstrdup(name, GFP_KERNEL);
2692 var->type = kstrdup(type, GFP_KERNEL);
2693 if (!var->var.name || !var->type) {
2694 kfree(var->var.name);
2695 kfree(var->type);
2696 kfree(var);
2697 var = ERR_PTR(-ENOMEM);
2698 }
2699 out:
2700 return var;
2701 }
2702
create_field_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_name)2703 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
2704 struct trace_event_file *file,
2705 char *field_name)
2706 {
2707 struct hist_field *val = NULL, *var = NULL;
2708 unsigned long flags = HIST_FIELD_FL_VAR;
2709 struct trace_array *tr = file->tr;
2710 struct field_var *field_var;
2711 int ret = 0;
2712
2713 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
2714 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2715 ret = -EINVAL;
2716 goto err;
2717 }
2718
2719 val = parse_atom(hist_data, file, field_name, &flags, NULL);
2720 if (IS_ERR(val)) {
2721 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name));
2722 ret = PTR_ERR(val);
2723 goto err;
2724 }
2725
2726 var = create_var(hist_data, file, field_name, val->size, val->type);
2727 if (IS_ERR(var)) {
2728 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name));
2729 kfree(val);
2730 ret = PTR_ERR(var);
2731 goto err;
2732 }
2733
2734 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
2735 if (!field_var) {
2736 kfree(val);
2737 kfree(var);
2738 ret = -ENOMEM;
2739 goto err;
2740 }
2741
2742 field_var->var = var;
2743 field_var->val = val;
2744 out:
2745 return field_var;
2746 err:
2747 field_var = ERR_PTR(ret);
2748 goto out;
2749 }
2750
2751 /**
2752 * create_target_field_var - Automatically create a variable for a field
2753 * @target_hist_data: The target hist trigger
2754 * @subsys_name: Optional subsystem name
2755 * @event_name: Optional event name
2756 * @var_name: The name of the field (and the resulting variable)
2757 *
2758 * Hist trigger actions fetch data from variables, not directly from
2759 * events. However, for convenience, users are allowed to directly
2760 * specify an event field in an action, which will be automatically
2761 * converted into a variable on their behalf.
2762
2763 * This function creates a field variable with the name var_name on
2764 * the hist trigger currently being defined on the target event. If
2765 * subsys_name and event_name are specified, this function simply
2766 * verifies that they do in fact match the target event subsystem and
2767 * event name.
2768 *
2769 * Return: The variable created for the field.
2770 */
2771 static struct field_var *
create_target_field_var(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * var_name)2772 create_target_field_var(struct hist_trigger_data *target_hist_data,
2773 char *subsys_name, char *event_name, char *var_name)
2774 {
2775 struct trace_event_file *file = target_hist_data->event_file;
2776
2777 if (subsys_name) {
2778 struct trace_event_call *call;
2779
2780 if (!event_name)
2781 return NULL;
2782
2783 call = file->event_call;
2784
2785 if (strcmp(subsys_name, call->class->system) != 0)
2786 return NULL;
2787
2788 if (strcmp(event_name, trace_event_name(call)) != 0)
2789 return NULL;
2790 }
2791
2792 return create_field_var(target_hist_data, file, var_name);
2793 }
2794
check_track_val_max(u64 track_val,u64 var_val)2795 static bool check_track_val_max(u64 track_val, u64 var_val)
2796 {
2797 if (var_val <= track_val)
2798 return false;
2799
2800 return true;
2801 }
2802
check_track_val_changed(u64 track_val,u64 var_val)2803 static bool check_track_val_changed(u64 track_val, u64 var_val)
2804 {
2805 if (var_val == track_val)
2806 return false;
2807
2808 return true;
2809 }
2810
get_track_val(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)2811 static u64 get_track_val(struct hist_trigger_data *hist_data,
2812 struct tracing_map_elt *elt,
2813 struct action_data *data)
2814 {
2815 unsigned int track_var_idx = data->track_data.track_var->var.idx;
2816 u64 track_val;
2817
2818 track_val = tracing_map_read_var(elt, track_var_idx);
2819
2820 return track_val;
2821 }
2822
save_track_val(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data,u64 var_val)2823 static void save_track_val(struct hist_trigger_data *hist_data,
2824 struct tracing_map_elt *elt,
2825 struct action_data *data, u64 var_val)
2826 {
2827 unsigned int track_var_idx = data->track_data.track_var->var.idx;
2828
2829 tracing_map_set_var(elt, track_var_idx, var_val);
2830 }
2831
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)2832 static void save_track_data(struct hist_trigger_data *hist_data,
2833 struct tracing_map_elt *elt, void *rec,
2834 struct ring_buffer_event *rbe, void *key,
2835 struct action_data *data, u64 *var_ref_vals)
2836 {
2837 if (data->track_data.save_data)
2838 data->track_data.save_data(hist_data, elt, rec, rbe, key, data, var_ref_vals);
2839 }
2840
check_track_val(struct tracing_map_elt * elt,struct action_data * data,u64 var_val)2841 static bool check_track_val(struct tracing_map_elt *elt,
2842 struct action_data *data,
2843 u64 var_val)
2844 {
2845 struct hist_trigger_data *hist_data;
2846 u64 track_val;
2847
2848 hist_data = data->track_data.track_var->hist_data;
2849 track_val = get_track_val(hist_data, elt, data);
2850
2851 return data->track_data.check_val(track_val, var_val);
2852 }
2853
2854 #ifdef CONFIG_TRACER_SNAPSHOT
cond_snapshot_update(struct trace_array * tr,void * cond_data)2855 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
2856 {
2857 /* called with tr->max_lock held */
2858 struct track_data *track_data = tr->cond_snapshot->cond_data;
2859 struct hist_elt_data *elt_data, *track_elt_data;
2860 struct snapshot_context *context = cond_data;
2861 struct action_data *action;
2862 u64 track_val;
2863
2864 if (!track_data)
2865 return false;
2866
2867 action = track_data->action_data;
2868
2869 track_val = get_track_val(track_data->hist_data, context->elt,
2870 track_data->action_data);
2871
2872 if (!action->track_data.check_val(track_data->track_val, track_val))
2873 return false;
2874
2875 track_data->track_val = track_val;
2876 memcpy(track_data->key, context->key, track_data->key_len);
2877
2878 elt_data = context->elt->private_data;
2879 track_elt_data = track_data->elt.private_data;
2880 if (elt_data->comm)
2881 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN);
2882
2883 track_data->updated = true;
2884
2885 return true;
2886 }
2887
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)2888 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
2889 struct tracing_map_elt *elt, void *rec,
2890 struct ring_buffer_event *rbe, void *key,
2891 struct action_data *data,
2892 u64 *var_ref_vals)
2893 {
2894 struct trace_event_file *file = hist_data->event_file;
2895 struct snapshot_context context;
2896
2897 context.elt = elt;
2898 context.key = key;
2899
2900 tracing_snapshot_cond(file->tr, &context);
2901 }
2902
2903 static void hist_trigger_print_key(struct seq_file *m,
2904 struct hist_trigger_data *hist_data,
2905 void *key,
2906 struct tracing_map_elt *elt);
2907
snapshot_action(struct hist_trigger_data * hist_data)2908 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
2909 {
2910 unsigned int i;
2911
2912 if (!hist_data->n_actions)
2913 return NULL;
2914
2915 for (i = 0; i < hist_data->n_actions; i++) {
2916 struct action_data *data = hist_data->actions[i];
2917
2918 if (data->action == ACTION_SNAPSHOT)
2919 return data;
2920 }
2921
2922 return NULL;
2923 }
2924
track_data_snapshot_print(struct seq_file * m,struct hist_trigger_data * hist_data)2925 static void track_data_snapshot_print(struct seq_file *m,
2926 struct hist_trigger_data *hist_data)
2927 {
2928 struct trace_event_file *file = hist_data->event_file;
2929 struct track_data *track_data;
2930 struct action_data *action;
2931
2932 track_data = tracing_cond_snapshot_data(file->tr);
2933 if (!track_data)
2934 return;
2935
2936 if (!track_data->updated)
2937 return;
2938
2939 action = snapshot_action(hist_data);
2940 if (!action)
2941 return;
2942
2943 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n");
2944 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu",
2945 action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
2946 action->track_data.var_str, track_data->track_val);
2947
2948 seq_puts(m, "\ttriggered by event with key: ");
2949 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt);
2950 seq_putc(m, '\n');
2951 }
2952 #else
cond_snapshot_update(struct trace_array * tr,void * cond_data)2953 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
2954 {
2955 return false;
2956 }
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)2957 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
2958 struct tracing_map_elt *elt, void *rec,
2959 struct ring_buffer_event *rbe, void *key,
2960 struct action_data *data,
2961 u64 *var_ref_vals) {}
track_data_snapshot_print(struct seq_file * m,struct hist_trigger_data * hist_data)2962 static void track_data_snapshot_print(struct seq_file *m,
2963 struct hist_trigger_data *hist_data) {}
2964 #endif /* CONFIG_TRACER_SNAPSHOT */
2965
track_data_print(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)2966 static void track_data_print(struct seq_file *m,
2967 struct hist_trigger_data *hist_data,
2968 struct tracing_map_elt *elt,
2969 struct action_data *data)
2970 {
2971 u64 track_val = get_track_val(hist_data, elt, data);
2972 unsigned int i, save_var_idx;
2973
2974 if (data->handler == HANDLER_ONMAX)
2975 seq_printf(m, "\n\tmax: %10llu", track_val);
2976 else if (data->handler == HANDLER_ONCHANGE)
2977 seq_printf(m, "\n\tchanged: %10llu", track_val);
2978
2979 if (data->action == ACTION_SNAPSHOT)
2980 return;
2981
2982 for (i = 0; i < hist_data->n_save_vars; i++) {
2983 struct hist_field *save_val = hist_data->save_vars[i]->val;
2984 struct hist_field *save_var = hist_data->save_vars[i]->var;
2985 u64 val;
2986
2987 save_var_idx = save_var->var.idx;
2988
2989 val = tracing_map_read_var(elt, save_var_idx);
2990
2991 if (save_val->flags & HIST_FIELD_FL_STRING) {
2992 seq_printf(m, " %s: %-32s", save_var->var.name,
2993 (char *)(uintptr_t)(val));
2994 } else
2995 seq_printf(m, " %s: %10llu", save_var->var.name, val);
2996 }
2997 }
2998
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)2999 static void ontrack_action(struct hist_trigger_data *hist_data,
3000 struct tracing_map_elt *elt, void *rec,
3001 struct ring_buffer_event *rbe, void *key,
3002 struct action_data *data, u64 *var_ref_vals)
3003 {
3004 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx];
3005
3006 if (check_track_val(elt, data, var_val)) {
3007 save_track_val(hist_data, elt, data, var_val);
3008 save_track_data(hist_data, elt, rec, rbe, key, data, var_ref_vals);
3009 }
3010 }
3011
action_data_destroy(struct action_data * data)3012 static void action_data_destroy(struct action_data *data)
3013 {
3014 unsigned int i;
3015
3016 lockdep_assert_held(&event_mutex);
3017
3018 kfree(data->action_name);
3019
3020 for (i = 0; i < data->n_params; i++)
3021 kfree(data->params[i]);
3022
3023 if (data->synth_event)
3024 data->synth_event->ref--;
3025
3026 kfree(data->synth_event_name);
3027
3028 kfree(data);
3029 }
3030
track_data_destroy(struct hist_trigger_data * hist_data,struct action_data * data)3031 static void track_data_destroy(struct hist_trigger_data *hist_data,
3032 struct action_data *data)
3033 {
3034 struct trace_event_file *file = hist_data->event_file;
3035
3036 destroy_hist_field(data->track_data.track_var, 0);
3037
3038 if (data->action == ACTION_SNAPSHOT) {
3039 struct track_data *track_data;
3040
3041 track_data = tracing_cond_snapshot_data(file->tr);
3042 if (track_data && track_data->hist_data == hist_data) {
3043 tracing_snapshot_cond_disable(file->tr);
3044 track_data_free(track_data);
3045 }
3046 }
3047
3048 kfree(data->track_data.var_str);
3049
3050 action_data_destroy(data);
3051 }
3052
3053 static int action_create(struct hist_trigger_data *hist_data,
3054 struct action_data *data);
3055
track_data_create(struct hist_trigger_data * hist_data,struct action_data * data)3056 static int track_data_create(struct hist_trigger_data *hist_data,
3057 struct action_data *data)
3058 {
3059 struct hist_field *var_field, *ref_field, *track_var = NULL;
3060 struct trace_event_file *file = hist_data->event_file;
3061 struct trace_array *tr = file->tr;
3062 char *track_data_var_str;
3063 int ret = 0;
3064
3065 track_data_var_str = data->track_data.var_str;
3066 if (track_data_var_str[0] != '$') {
3067 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str));
3068 return -EINVAL;
3069 }
3070 track_data_var_str++;
3071
3072 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str);
3073 if (!var_field) {
3074 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str));
3075 return -EINVAL;
3076 }
3077
3078 ref_field = create_var_ref(hist_data, var_field, NULL, NULL);
3079 if (!ref_field)
3080 return -ENOMEM;
3081
3082 data->track_data.var_ref = ref_field;
3083
3084 if (data->handler == HANDLER_ONMAX)
3085 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64");
3086 if (IS_ERR(track_var)) {
3087 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3088 ret = PTR_ERR(track_var);
3089 goto out;
3090 }
3091
3092 if (data->handler == HANDLER_ONCHANGE)
3093 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64");
3094 if (IS_ERR(track_var)) {
3095 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3096 ret = PTR_ERR(track_var);
3097 goto out;
3098 }
3099 data->track_data.track_var = track_var;
3100
3101 ret = action_create(hist_data, data);
3102 out:
3103 return ret;
3104 }
3105
parse_action_params(struct trace_array * tr,char * params,struct action_data * data)3106 static int parse_action_params(struct trace_array *tr, char *params,
3107 struct action_data *data)
3108 {
3109 char *param, *saved_param;
3110 bool first_param = true;
3111 int ret = 0;
3112
3113 while (params) {
3114 if (data->n_params >= SYNTH_FIELDS_MAX) {
3115 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0);
3116 goto out;
3117 }
3118
3119 param = strsep(¶ms, ",");
3120 if (!param) {
3121 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0);
3122 ret = -EINVAL;
3123 goto out;
3124 }
3125
3126 param = strstrip(param);
3127 if (strlen(param) < 2) {
3128 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param));
3129 ret = -EINVAL;
3130 goto out;
3131 }
3132
3133 saved_param = kstrdup(param, GFP_KERNEL);
3134 if (!saved_param) {
3135 ret = -ENOMEM;
3136 goto out;
3137 }
3138
3139 if (first_param && data->use_trace_keyword) {
3140 data->synth_event_name = saved_param;
3141 first_param = false;
3142 continue;
3143 }
3144 first_param = false;
3145
3146 data->params[data->n_params++] = saved_param;
3147 }
3148 out:
3149 return ret;
3150 }
3151
action_parse(struct trace_array * tr,char * str,struct action_data * data,enum handler_id handler)3152 static int action_parse(struct trace_array *tr, char *str, struct action_data *data,
3153 enum handler_id handler)
3154 {
3155 char *action_name;
3156 int ret = 0;
3157
3158 strsep(&str, ".");
3159 if (!str) {
3160 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3161 ret = -EINVAL;
3162 goto out;
3163 }
3164
3165 action_name = strsep(&str, "(");
3166 if (!action_name || !str) {
3167 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3168 ret = -EINVAL;
3169 goto out;
3170 }
3171
3172 if (str_has_prefix(action_name, "save")) {
3173 char *params = strsep(&str, ")");
3174
3175 if (!params) {
3176 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0);
3177 ret = -EINVAL;
3178 goto out;
3179 }
3180
3181 ret = parse_action_params(tr, params, data);
3182 if (ret)
3183 goto out;
3184
3185 if (handler == HANDLER_ONMAX)
3186 data->track_data.check_val = check_track_val_max;
3187 else if (handler == HANDLER_ONCHANGE)
3188 data->track_data.check_val = check_track_val_changed;
3189 else {
3190 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3191 ret = -EINVAL;
3192 goto out;
3193 }
3194
3195 data->track_data.save_data = save_track_data_vars;
3196 data->fn = ontrack_action;
3197 data->action = ACTION_SAVE;
3198 } else if (str_has_prefix(action_name, "snapshot")) {
3199 char *params = strsep(&str, ")");
3200
3201 if (!str) {
3202 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params));
3203 ret = -EINVAL;
3204 goto out;
3205 }
3206
3207 if (handler == HANDLER_ONMAX)
3208 data->track_data.check_val = check_track_val_max;
3209 else if (handler == HANDLER_ONCHANGE)
3210 data->track_data.check_val = check_track_val_changed;
3211 else {
3212 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3213 ret = -EINVAL;
3214 goto out;
3215 }
3216
3217 data->track_data.save_data = save_track_data_snapshot;
3218 data->fn = ontrack_action;
3219 data->action = ACTION_SNAPSHOT;
3220 } else {
3221 char *params = strsep(&str, ")");
3222
3223 if (str_has_prefix(action_name, "trace"))
3224 data->use_trace_keyword = true;
3225
3226 if (params) {
3227 ret = parse_action_params(tr, params, data);
3228 if (ret)
3229 goto out;
3230 }
3231
3232 if (handler == HANDLER_ONMAX)
3233 data->track_data.check_val = check_track_val_max;
3234 else if (handler == HANDLER_ONCHANGE)
3235 data->track_data.check_val = check_track_val_changed;
3236
3237 if (handler != HANDLER_ONMATCH) {
3238 data->track_data.save_data = action_trace;
3239 data->fn = ontrack_action;
3240 } else
3241 data->fn = action_trace;
3242
3243 data->action = ACTION_TRACE;
3244 }
3245
3246 data->action_name = kstrdup(action_name, GFP_KERNEL);
3247 if (!data->action_name) {
3248 ret = -ENOMEM;
3249 goto out;
3250 }
3251
3252 data->handler = handler;
3253 out:
3254 return ret;
3255 }
3256
track_data_parse(struct hist_trigger_data * hist_data,char * str,enum handler_id handler)3257 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data,
3258 char *str, enum handler_id handler)
3259 {
3260 struct action_data *data;
3261 int ret = -EINVAL;
3262 char *var_str;
3263
3264 data = kzalloc(sizeof(*data), GFP_KERNEL);
3265 if (!data)
3266 return ERR_PTR(-ENOMEM);
3267
3268 var_str = strsep(&str, ")");
3269 if (!var_str || !str) {
3270 ret = -EINVAL;
3271 goto free;
3272 }
3273
3274 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL);
3275 if (!data->track_data.var_str) {
3276 ret = -ENOMEM;
3277 goto free;
3278 }
3279
3280 ret = action_parse(hist_data->event_file->tr, str, data, handler);
3281 if (ret)
3282 goto free;
3283 out:
3284 return data;
3285 free:
3286 track_data_destroy(hist_data, data);
3287 data = ERR_PTR(ret);
3288 goto out;
3289 }
3290
onmatch_destroy(struct action_data * data)3291 static void onmatch_destroy(struct action_data *data)
3292 {
3293 kfree(data->match_data.event);
3294 kfree(data->match_data.event_system);
3295
3296 action_data_destroy(data);
3297 }
3298
destroy_field_var(struct field_var * field_var)3299 static void destroy_field_var(struct field_var *field_var)
3300 {
3301 if (!field_var)
3302 return;
3303
3304 destroy_hist_field(field_var->var, 0);
3305 destroy_hist_field(field_var->val, 0);
3306
3307 kfree(field_var);
3308 }
3309
destroy_field_vars(struct hist_trigger_data * hist_data)3310 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3311 {
3312 unsigned int i;
3313
3314 for (i = 0; i < hist_data->n_field_vars; i++)
3315 destroy_field_var(hist_data->field_vars[i]);
3316
3317 for (i = 0; i < hist_data->n_save_vars; i++)
3318 destroy_field_var(hist_data->save_vars[i]);
3319 }
3320
save_field_var(struct hist_trigger_data * hist_data,struct field_var * field_var)3321 static void save_field_var(struct hist_trigger_data *hist_data,
3322 struct field_var *field_var)
3323 {
3324 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3325
3326 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3327 hist_data->n_field_var_str++;
3328 }
3329
3330
check_synth_field(struct synth_event * event,struct hist_field * hist_field,unsigned int field_pos)3331 static int check_synth_field(struct synth_event *event,
3332 struct hist_field *hist_field,
3333 unsigned int field_pos)
3334 {
3335 struct synth_field *field;
3336
3337 if (field_pos >= event->n_fields)
3338 return -EINVAL;
3339
3340 field = event->fields[field_pos];
3341
3342 /*
3343 * A dynamic string synth field can accept static or
3344 * dynamic. A static string synth field can only accept a
3345 * same-sized static string, which is checked for later.
3346 */
3347 if (strstr(hist_field->type, "char[") && field->is_string
3348 && field->is_dynamic)
3349 return 0;
3350
3351 if (strcmp(field->type, hist_field->type) != 0) {
3352 if (field->size != hist_field->size ||
3353 (!field->is_string && field->is_signed != hist_field->is_signed))
3354 return -EINVAL;
3355 }
3356
3357 return 0;
3358 }
3359
3360 static struct hist_field *
trace_action_find_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3361 trace_action_find_var(struct hist_trigger_data *hist_data,
3362 struct action_data *data,
3363 char *system, char *event, char *var)
3364 {
3365 struct trace_array *tr = hist_data->event_file->tr;
3366 struct hist_field *hist_field;
3367
3368 var++; /* skip '$' */
3369
3370 hist_field = find_target_event_var(hist_data, system, event, var);
3371 if (!hist_field) {
3372 if (!system && data->handler == HANDLER_ONMATCH) {
3373 system = data->match_data.event_system;
3374 event = data->match_data.event;
3375 }
3376
3377 hist_field = find_event_var(hist_data, system, event, var);
3378 }
3379
3380 if (!hist_field)
3381 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var));
3382
3383 return hist_field;
3384 }
3385
3386 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)3387 trace_action_create_field_var(struct hist_trigger_data *hist_data,
3388 struct action_data *data, char *system,
3389 char *event, char *var)
3390 {
3391 struct hist_field *hist_field = NULL;
3392 struct field_var *field_var;
3393
3394 /*
3395 * First try to create a field var on the target event (the
3396 * currently being defined). This will create a variable for
3397 * unqualified fields on the target event, or if qualified,
3398 * target fields that have qualified names matching the target.
3399 */
3400 field_var = create_target_field_var(hist_data, system, event, var);
3401
3402 if (field_var && !IS_ERR(field_var)) {
3403 save_field_var(hist_data, field_var);
3404 hist_field = field_var->var;
3405 } else {
3406 field_var = NULL;
3407 /*
3408 * If no explicit system.event is specfied, default to
3409 * looking for fields on the onmatch(system.event.xxx)
3410 * event.
3411 */
3412 if (!system && data->handler == HANDLER_ONMATCH) {
3413 system = data->match_data.event_system;
3414 event = data->match_data.event;
3415 }
3416
3417 if (!event)
3418 goto free;
3419 /*
3420 * At this point, we're looking at a field on another
3421 * event. Because we can't modify a hist trigger on
3422 * another event to add a variable for a field, we need
3423 * to create a new trigger on that event and create the
3424 * variable at the same time.
3425 */
3426 hist_field = create_field_var_hist(hist_data, system, event, var);
3427 if (IS_ERR(hist_field))
3428 goto free;
3429 }
3430 out:
3431 return hist_field;
3432 free:
3433 destroy_field_var(field_var);
3434 hist_field = NULL;
3435 goto out;
3436 }
3437
trace_action_create(struct hist_trigger_data * hist_data,struct action_data * data)3438 static int trace_action_create(struct hist_trigger_data *hist_data,
3439 struct action_data *data)
3440 {
3441 struct trace_array *tr = hist_data->event_file->tr;
3442 char *event_name, *param, *system = NULL;
3443 struct hist_field *hist_field, *var_ref;
3444 unsigned int i;
3445 unsigned int field_pos = 0;
3446 struct synth_event *event;
3447 char *synth_event_name;
3448 int var_ref_idx, ret = 0;
3449
3450 lockdep_assert_held(&event_mutex);
3451
3452 if (data->use_trace_keyword)
3453 synth_event_name = data->synth_event_name;
3454 else
3455 synth_event_name = data->action_name;
3456
3457 event = find_synth_event(synth_event_name);
3458 if (!event) {
3459 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name));
3460 return -EINVAL;
3461 }
3462
3463 event->ref++;
3464
3465 for (i = 0; i < data->n_params; i++) {
3466 char *p;
3467
3468 p = param = kstrdup(data->params[i], GFP_KERNEL);
3469 if (!param) {
3470 ret = -ENOMEM;
3471 goto err;
3472 }
3473
3474 system = strsep(¶m, ".");
3475 if (!param) {
3476 param = (char *)system;
3477 system = event_name = NULL;
3478 } else {
3479 event_name = strsep(¶m, ".");
3480 if (!param) {
3481 kfree(p);
3482 ret = -EINVAL;
3483 goto err;
3484 }
3485 }
3486
3487 if (param[0] == '$')
3488 hist_field = trace_action_find_var(hist_data, data,
3489 system, event_name,
3490 param);
3491 else
3492 hist_field = trace_action_create_field_var(hist_data,
3493 data,
3494 system,
3495 event_name,
3496 param);
3497
3498 if (!hist_field) {
3499 kfree(p);
3500 ret = -EINVAL;
3501 goto err;
3502 }
3503
3504 if (check_synth_field(event, hist_field, field_pos) == 0) {
3505 var_ref = create_var_ref(hist_data, hist_field,
3506 system, event_name);
3507 if (!var_ref) {
3508 kfree(p);
3509 ret = -ENOMEM;
3510 goto err;
3511 }
3512
3513 var_ref_idx = find_var_ref_idx(hist_data, var_ref);
3514 if (WARN_ON(var_ref_idx < 0)) {
3515 kfree(p);
3516 ret = var_ref_idx;
3517 goto err;
3518 }
3519
3520 data->var_ref_idx[i] = var_ref_idx;
3521
3522 field_pos++;
3523 kfree(p);
3524 continue;
3525 }
3526
3527 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param));
3528 kfree(p);
3529 ret = -EINVAL;
3530 goto err;
3531 }
3532
3533 if (field_pos != event->n_fields) {
3534 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name));
3535 ret = -EINVAL;
3536 goto err;
3537 }
3538
3539 data->synth_event = event;
3540 out:
3541 return ret;
3542 err:
3543 event->ref--;
3544
3545 goto out;
3546 }
3547
action_create(struct hist_trigger_data * hist_data,struct action_data * data)3548 static int action_create(struct hist_trigger_data *hist_data,
3549 struct action_data *data)
3550 {
3551 struct trace_event_file *file = hist_data->event_file;
3552 struct trace_array *tr = file->tr;
3553 struct track_data *track_data;
3554 struct field_var *field_var;
3555 unsigned int i;
3556 char *param;
3557 int ret = 0;
3558
3559 if (data->action == ACTION_TRACE)
3560 return trace_action_create(hist_data, data);
3561
3562 if (data->action == ACTION_SNAPSHOT) {
3563 track_data = track_data_alloc(hist_data->key_size, data, hist_data);
3564 if (IS_ERR(track_data)) {
3565 ret = PTR_ERR(track_data);
3566 goto out;
3567 }
3568
3569 ret = tracing_snapshot_cond_enable(file->tr, track_data,
3570 cond_snapshot_update);
3571 if (ret)
3572 track_data_free(track_data);
3573
3574 goto out;
3575 }
3576
3577 if (data->action == ACTION_SAVE) {
3578 if (hist_data->n_save_vars) {
3579 ret = -EEXIST;
3580 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0);
3581 goto out;
3582 }
3583
3584 for (i = 0; i < data->n_params; i++) {
3585 param = kstrdup(data->params[i], GFP_KERNEL);
3586 if (!param) {
3587 ret = -ENOMEM;
3588 goto out;
3589 }
3590
3591 field_var = create_target_field_var(hist_data, NULL, NULL, param);
3592 if (IS_ERR(field_var)) {
3593 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL,
3594 errpos(param));
3595 ret = PTR_ERR(field_var);
3596 kfree(param);
3597 goto out;
3598 }
3599
3600 hist_data->save_vars[hist_data->n_save_vars++] = field_var;
3601 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3602 hist_data->n_save_var_str++;
3603 kfree(param);
3604 }
3605 }
3606 out:
3607 return ret;
3608 }
3609
onmatch_create(struct hist_trigger_data * hist_data,struct action_data * data)3610 static int onmatch_create(struct hist_trigger_data *hist_data,
3611 struct action_data *data)
3612 {
3613 return action_create(hist_data, data);
3614 }
3615
onmatch_parse(struct trace_array * tr,char * str)3616 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
3617 {
3618 char *match_event, *match_event_system;
3619 struct action_data *data;
3620 int ret = -EINVAL;
3621
3622 data = kzalloc(sizeof(*data), GFP_KERNEL);
3623 if (!data)
3624 return ERR_PTR(-ENOMEM);
3625
3626 match_event = strsep(&str, ")");
3627 if (!match_event || !str) {
3628 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event));
3629 goto free;
3630 }
3631
3632 match_event_system = strsep(&match_event, ".");
3633 if (!match_event) {
3634 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system));
3635 goto free;
3636 }
3637
3638 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
3639 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event));
3640 goto free;
3641 }
3642
3643 data->match_data.event = kstrdup(match_event, GFP_KERNEL);
3644 if (!data->match_data.event) {
3645 ret = -ENOMEM;
3646 goto free;
3647 }
3648
3649 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL);
3650 if (!data->match_data.event_system) {
3651 ret = -ENOMEM;
3652 goto free;
3653 }
3654
3655 ret = action_parse(tr, str, data, HANDLER_ONMATCH);
3656 if (ret)
3657 goto free;
3658 out:
3659 return data;
3660 free:
3661 onmatch_destroy(data);
3662 data = ERR_PTR(ret);
3663 goto out;
3664 }
3665
create_hitcount_val(struct hist_trigger_data * hist_data)3666 static int create_hitcount_val(struct hist_trigger_data *hist_data)
3667 {
3668 hist_data->fields[HITCOUNT_IDX] =
3669 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
3670 if (!hist_data->fields[HITCOUNT_IDX])
3671 return -ENOMEM;
3672
3673 hist_data->n_vals++;
3674 hist_data->n_fields++;
3675
3676 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
3677 return -EINVAL;
3678
3679 return 0;
3680 }
3681
__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)3682 static int __create_val_field(struct hist_trigger_data *hist_data,
3683 unsigned int val_idx,
3684 struct trace_event_file *file,
3685 char *var_name, char *field_str,
3686 unsigned long flags)
3687 {
3688 struct hist_field *hist_field;
3689 int ret = 0;
3690
3691 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
3692 if (IS_ERR(hist_field)) {
3693 ret = PTR_ERR(hist_field);
3694 goto out;
3695 }
3696
3697 hist_data->fields[val_idx] = hist_field;
3698
3699 ++hist_data->n_vals;
3700 ++hist_data->n_fields;
3701
3702 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3703 ret = -EINVAL;
3704 out:
3705 return ret;
3706 }
3707
create_val_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * field_str)3708 static int create_val_field(struct hist_trigger_data *hist_data,
3709 unsigned int val_idx,
3710 struct trace_event_file *file,
3711 char *field_str)
3712 {
3713 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
3714 return -EINVAL;
3715
3716 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
3717 }
3718
create_var_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * var_name,char * expr_str)3719 static int create_var_field(struct hist_trigger_data *hist_data,
3720 unsigned int val_idx,
3721 struct trace_event_file *file,
3722 char *var_name, char *expr_str)
3723 {
3724 struct trace_array *tr = hist_data->event_file->tr;
3725 unsigned long flags = 0;
3726 int ret;
3727
3728 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3729 return -EINVAL;
3730
3731 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
3732 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name));
3733 return -EINVAL;
3734 }
3735
3736 flags |= HIST_FIELD_FL_VAR;
3737 hist_data->n_vars++;
3738 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
3739 return -EINVAL;
3740
3741 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
3742
3743 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING)
3744 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
3745
3746 return ret;
3747 }
3748
create_val_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3749 static int create_val_fields(struct hist_trigger_data *hist_data,
3750 struct trace_event_file *file)
3751 {
3752 char *fields_str, *field_str;
3753 unsigned int i, j = 1;
3754 int ret;
3755
3756 ret = create_hitcount_val(hist_data);
3757 if (ret)
3758 goto out;
3759
3760 fields_str = hist_data->attrs->vals_str;
3761 if (!fields_str)
3762 goto out;
3763
3764 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
3765 j < TRACING_MAP_VALS_MAX; i++) {
3766 field_str = strsep(&fields_str, ",");
3767 if (!field_str)
3768 break;
3769
3770 if (strcmp(field_str, "hitcount") == 0)
3771 continue;
3772
3773 ret = create_val_field(hist_data, j++, file, field_str);
3774 if (ret)
3775 goto out;
3776 }
3777
3778 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
3779 ret = -EINVAL;
3780 out:
3781 return ret;
3782 }
3783
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)3784 static int create_key_field(struct hist_trigger_data *hist_data,
3785 unsigned int key_idx,
3786 unsigned int key_offset,
3787 struct trace_event_file *file,
3788 char *field_str)
3789 {
3790 struct trace_array *tr = hist_data->event_file->tr;
3791 struct hist_field *hist_field = NULL;
3792 unsigned long flags = 0;
3793 unsigned int key_size;
3794 int ret = 0;
3795
3796 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
3797 return -EINVAL;
3798
3799 flags |= HIST_FIELD_FL_KEY;
3800
3801 if (strcmp(field_str, "stacktrace") == 0) {
3802 flags |= HIST_FIELD_FL_STACKTRACE;
3803 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
3804 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
3805 } else {
3806 hist_field = parse_expr(hist_data, file, field_str, flags,
3807 NULL, 0);
3808 if (IS_ERR(hist_field)) {
3809 ret = PTR_ERR(hist_field);
3810 goto out;
3811 }
3812
3813 if (field_has_hist_vars(hist_field, 0)) {
3814 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str));
3815 destroy_hist_field(hist_field, 0);
3816 ret = -EINVAL;
3817 goto out;
3818 }
3819
3820 key_size = hist_field->size;
3821 }
3822
3823 hist_data->fields[key_idx] = hist_field;
3824
3825 key_size = ALIGN(key_size, sizeof(u64));
3826 hist_data->fields[key_idx]->size = key_size;
3827 hist_data->fields[key_idx]->offset = key_offset;
3828
3829 hist_data->key_size += key_size;
3830
3831 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
3832 ret = -EINVAL;
3833 goto out;
3834 }
3835
3836 hist_data->n_keys++;
3837 hist_data->n_fields++;
3838
3839 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
3840 return -EINVAL;
3841
3842 ret = key_size;
3843 out:
3844 return ret;
3845 }
3846
create_key_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3847 static int create_key_fields(struct hist_trigger_data *hist_data,
3848 struct trace_event_file *file)
3849 {
3850 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
3851 char *fields_str, *field_str;
3852 int ret = -EINVAL;
3853
3854 fields_str = hist_data->attrs->keys_str;
3855 if (!fields_str)
3856 goto out;
3857
3858 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
3859 field_str = strsep(&fields_str, ",");
3860 if (!field_str)
3861 break;
3862 ret = create_key_field(hist_data, i, key_offset,
3863 file, field_str);
3864 if (ret < 0)
3865 goto out;
3866 key_offset += ret;
3867 }
3868 if (fields_str) {
3869 ret = -EINVAL;
3870 goto out;
3871 }
3872 ret = 0;
3873 out:
3874 return ret;
3875 }
3876
create_var_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3877 static int create_var_fields(struct hist_trigger_data *hist_data,
3878 struct trace_event_file *file)
3879 {
3880 unsigned int i, j = hist_data->n_vals;
3881 int ret = 0;
3882
3883 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
3884
3885 for (i = 0; i < n_vars; i++) {
3886 char *var_name = hist_data->attrs->var_defs.name[i];
3887 char *expr = hist_data->attrs->var_defs.expr[i];
3888
3889 ret = create_var_field(hist_data, j++, file, var_name, expr);
3890 if (ret)
3891 goto out;
3892 }
3893 out:
3894 return ret;
3895 }
3896
free_var_defs(struct hist_trigger_data * hist_data)3897 static void free_var_defs(struct hist_trigger_data *hist_data)
3898 {
3899 unsigned int i;
3900
3901 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
3902 kfree(hist_data->attrs->var_defs.name[i]);
3903 kfree(hist_data->attrs->var_defs.expr[i]);
3904 }
3905
3906 hist_data->attrs->var_defs.n_vars = 0;
3907 }
3908
parse_var_defs(struct hist_trigger_data * hist_data)3909 static int parse_var_defs(struct hist_trigger_data *hist_data)
3910 {
3911 struct trace_array *tr = hist_data->event_file->tr;
3912 char *s, *str, *var_name, *field_str;
3913 unsigned int i, j, n_vars = 0;
3914 int ret = 0;
3915
3916 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
3917 str = hist_data->attrs->assignment_str[i];
3918 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
3919 field_str = strsep(&str, ",");
3920 if (!field_str)
3921 break;
3922
3923 var_name = strsep(&field_str, "=");
3924 if (!var_name || !field_str) {
3925 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT,
3926 errpos(var_name));
3927 ret = -EINVAL;
3928 goto free;
3929 }
3930
3931 if (n_vars == TRACING_MAP_VARS_MAX) {
3932 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name));
3933 ret = -EINVAL;
3934 goto free;
3935 }
3936
3937 s = kstrdup(var_name, GFP_KERNEL);
3938 if (!s) {
3939 ret = -ENOMEM;
3940 goto free;
3941 }
3942 hist_data->attrs->var_defs.name[n_vars] = s;
3943
3944 s = kstrdup(field_str, GFP_KERNEL);
3945 if (!s) {
3946 kfree(hist_data->attrs->var_defs.name[n_vars]);
3947 hist_data->attrs->var_defs.name[n_vars] = NULL;
3948 ret = -ENOMEM;
3949 goto free;
3950 }
3951 hist_data->attrs->var_defs.expr[n_vars++] = s;
3952
3953 hist_data->attrs->var_defs.n_vars = n_vars;
3954 }
3955 }
3956
3957 return ret;
3958 free:
3959 free_var_defs(hist_data);
3960
3961 return ret;
3962 }
3963
create_hist_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3964 static int create_hist_fields(struct hist_trigger_data *hist_data,
3965 struct trace_event_file *file)
3966 {
3967 int ret;
3968
3969 ret = parse_var_defs(hist_data);
3970 if (ret)
3971 goto out;
3972
3973 ret = create_val_fields(hist_data, file);
3974 if (ret)
3975 goto out;
3976
3977 ret = create_var_fields(hist_data, file);
3978 if (ret)
3979 goto out;
3980
3981 ret = create_key_fields(hist_data, file);
3982 if (ret)
3983 goto out;
3984 out:
3985 free_var_defs(hist_data);
3986
3987 return ret;
3988 }
3989
is_descending(struct trace_array * tr,const char * str)3990 static int is_descending(struct trace_array *tr, const char *str)
3991 {
3992 if (!str)
3993 return 0;
3994
3995 if (strcmp(str, "descending") == 0)
3996 return 1;
3997
3998 if (strcmp(str, "ascending") == 0)
3999 return 0;
4000
4001 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str));
4002
4003 return -EINVAL;
4004 }
4005
create_sort_keys(struct hist_trigger_data * hist_data)4006 static int create_sort_keys(struct hist_trigger_data *hist_data)
4007 {
4008 struct trace_array *tr = hist_data->event_file->tr;
4009 char *fields_str = hist_data->attrs->sort_key_str;
4010 struct tracing_map_sort_key *sort_key;
4011 int descending, ret = 0;
4012 unsigned int i, j, k;
4013
4014 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4015
4016 if (!fields_str)
4017 goto out;
4018
4019 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4020 struct hist_field *hist_field;
4021 char *field_str, *field_name;
4022 const char *test_name;
4023
4024 sort_key = &hist_data->sort_keys[i];
4025
4026 field_str = strsep(&fields_str, ",");
4027 if (!field_str)
4028 break;
4029
4030 if (!*field_str) {
4031 ret = -EINVAL;
4032 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4033 break;
4034 }
4035
4036 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4037 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort="));
4038 ret = -EINVAL;
4039 break;
4040 }
4041
4042 field_name = strsep(&field_str, ".");
4043 if (!field_name || !*field_name) {
4044 ret = -EINVAL;
4045 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4046 break;
4047 }
4048
4049 if (strcmp(field_name, "hitcount") == 0) {
4050 descending = is_descending(tr, field_str);
4051 if (descending < 0) {
4052 ret = descending;
4053 break;
4054 }
4055 sort_key->descending = descending;
4056 continue;
4057 }
4058
4059 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4060 unsigned int idx;
4061
4062 hist_field = hist_data->fields[j];
4063 if (hist_field->flags & HIST_FIELD_FL_VAR)
4064 continue;
4065
4066 idx = k++;
4067
4068 test_name = hist_field_name(hist_field, 0);
4069
4070 if (strcmp(field_name, test_name) == 0) {
4071 sort_key->field_idx = idx;
4072 descending = is_descending(tr, field_str);
4073 if (descending < 0) {
4074 ret = descending;
4075 goto out;
4076 }
4077 sort_key->descending = descending;
4078 break;
4079 }
4080 }
4081 if (j == hist_data->n_fields) {
4082 ret = -EINVAL;
4083 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name));
4084 break;
4085 }
4086 }
4087
4088 hist_data->n_sort_keys = i;
4089 out:
4090 return ret;
4091 }
4092
destroy_actions(struct hist_trigger_data * hist_data)4093 static void destroy_actions(struct hist_trigger_data *hist_data)
4094 {
4095 unsigned int i;
4096
4097 for (i = 0; i < hist_data->n_actions; i++) {
4098 struct action_data *data = hist_data->actions[i];
4099
4100 if (data->handler == HANDLER_ONMATCH)
4101 onmatch_destroy(data);
4102 else if (data->handler == HANDLER_ONMAX ||
4103 data->handler == HANDLER_ONCHANGE)
4104 track_data_destroy(hist_data, data);
4105 else
4106 kfree(data);
4107 }
4108 }
4109
parse_actions(struct hist_trigger_data * hist_data)4110 static int parse_actions(struct hist_trigger_data *hist_data)
4111 {
4112 struct trace_array *tr = hist_data->event_file->tr;
4113 struct action_data *data;
4114 unsigned int i;
4115 int ret = 0;
4116 char *str;
4117 int len;
4118
4119 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4120 str = hist_data->attrs->action_str[i];
4121
4122 if ((len = str_has_prefix(str, "onmatch("))) {
4123 char *action_str = str + len;
4124
4125 data = onmatch_parse(tr, action_str);
4126 if (IS_ERR(data)) {
4127 ret = PTR_ERR(data);
4128 break;
4129 }
4130 } else if ((len = str_has_prefix(str, "onmax("))) {
4131 char *action_str = str + len;
4132
4133 data = track_data_parse(hist_data, action_str,
4134 HANDLER_ONMAX);
4135 if (IS_ERR(data)) {
4136 ret = PTR_ERR(data);
4137 break;
4138 }
4139 } else if ((len = str_has_prefix(str, "onchange("))) {
4140 char *action_str = str + len;
4141
4142 data = track_data_parse(hist_data, action_str,
4143 HANDLER_ONCHANGE);
4144 if (IS_ERR(data)) {
4145 ret = PTR_ERR(data);
4146 break;
4147 }
4148 } else {
4149 ret = -EINVAL;
4150 break;
4151 }
4152
4153 hist_data->actions[hist_data->n_actions++] = data;
4154 }
4155
4156 return ret;
4157 }
4158
create_actions(struct hist_trigger_data * hist_data)4159 static int create_actions(struct hist_trigger_data *hist_data)
4160 {
4161 struct action_data *data;
4162 unsigned int i;
4163 int ret = 0;
4164
4165 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4166 data = hist_data->actions[i];
4167
4168 if (data->handler == HANDLER_ONMATCH) {
4169 ret = onmatch_create(hist_data, data);
4170 if (ret)
4171 break;
4172 } else if (data->handler == HANDLER_ONMAX ||
4173 data->handler == HANDLER_ONCHANGE) {
4174 ret = track_data_create(hist_data, data);
4175 if (ret)
4176 break;
4177 } else {
4178 ret = -EINVAL;
4179 break;
4180 }
4181 }
4182
4183 return ret;
4184 }
4185
print_actions(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt)4186 static void print_actions(struct seq_file *m,
4187 struct hist_trigger_data *hist_data,
4188 struct tracing_map_elt *elt)
4189 {
4190 unsigned int i;
4191
4192 for (i = 0; i < hist_data->n_actions; i++) {
4193 struct action_data *data = hist_data->actions[i];
4194
4195 if (data->action == ACTION_SNAPSHOT)
4196 continue;
4197
4198 if (data->handler == HANDLER_ONMAX ||
4199 data->handler == HANDLER_ONCHANGE)
4200 track_data_print(m, hist_data, elt, data);
4201 }
4202 }
4203
print_action_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4204 static void print_action_spec(struct seq_file *m,
4205 struct hist_trigger_data *hist_data,
4206 struct action_data *data)
4207 {
4208 unsigned int i;
4209
4210 if (data->action == ACTION_SAVE) {
4211 for (i = 0; i < hist_data->n_save_vars; i++) {
4212 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name);
4213 if (i < hist_data->n_save_vars - 1)
4214 seq_puts(m, ",");
4215 }
4216 } else if (data->action == ACTION_TRACE) {
4217 if (data->use_trace_keyword)
4218 seq_printf(m, "%s", data->synth_event_name);
4219 for (i = 0; i < data->n_params; i++) {
4220 if (i || data->use_trace_keyword)
4221 seq_puts(m, ",");
4222 seq_printf(m, "%s", data->params[i]);
4223 }
4224 }
4225 }
4226
print_track_data_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4227 static void print_track_data_spec(struct seq_file *m,
4228 struct hist_trigger_data *hist_data,
4229 struct action_data *data)
4230 {
4231 if (data->handler == HANDLER_ONMAX)
4232 seq_puts(m, ":onmax(");
4233 else if (data->handler == HANDLER_ONCHANGE)
4234 seq_puts(m, ":onchange(");
4235 seq_printf(m, "%s", data->track_data.var_str);
4236 seq_printf(m, ").%s(", data->action_name);
4237
4238 print_action_spec(m, hist_data, data);
4239
4240 seq_puts(m, ")");
4241 }
4242
print_onmatch_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4243 static void print_onmatch_spec(struct seq_file *m,
4244 struct hist_trigger_data *hist_data,
4245 struct action_data *data)
4246 {
4247 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system,
4248 data->match_data.event);
4249
4250 seq_printf(m, "%s(", data->action_name);
4251
4252 print_action_spec(m, hist_data, data);
4253
4254 seq_puts(m, ")");
4255 }
4256
actions_match(struct hist_trigger_data * hist_data,struct hist_trigger_data * hist_data_test)4257 static bool actions_match(struct hist_trigger_data *hist_data,
4258 struct hist_trigger_data *hist_data_test)
4259 {
4260 unsigned int i, j;
4261
4262 if (hist_data->n_actions != hist_data_test->n_actions)
4263 return false;
4264
4265 for (i = 0; i < hist_data->n_actions; i++) {
4266 struct action_data *data = hist_data->actions[i];
4267 struct action_data *data_test = hist_data_test->actions[i];
4268 char *action_name, *action_name_test;
4269
4270 if (data->handler != data_test->handler)
4271 return false;
4272 if (data->action != data_test->action)
4273 return false;
4274
4275 if (data->n_params != data_test->n_params)
4276 return false;
4277
4278 for (j = 0; j < data->n_params; j++) {
4279 if (strcmp(data->params[j], data_test->params[j]) != 0)
4280 return false;
4281 }
4282
4283 if (data->use_trace_keyword)
4284 action_name = data->synth_event_name;
4285 else
4286 action_name = data->action_name;
4287
4288 if (data_test->use_trace_keyword)
4289 action_name_test = data_test->synth_event_name;
4290 else
4291 action_name_test = data_test->action_name;
4292
4293 if (strcmp(action_name, action_name_test) != 0)
4294 return false;
4295
4296 if (data->handler == HANDLER_ONMATCH) {
4297 if (strcmp(data->match_data.event_system,
4298 data_test->match_data.event_system) != 0)
4299 return false;
4300 if (strcmp(data->match_data.event,
4301 data_test->match_data.event) != 0)
4302 return false;
4303 } else if (data->handler == HANDLER_ONMAX ||
4304 data->handler == HANDLER_ONCHANGE) {
4305 if (strcmp(data->track_data.var_str,
4306 data_test->track_data.var_str) != 0)
4307 return false;
4308 }
4309 }
4310
4311 return true;
4312 }
4313
4314
print_actions_spec(struct seq_file * m,struct hist_trigger_data * hist_data)4315 static void print_actions_spec(struct seq_file *m,
4316 struct hist_trigger_data *hist_data)
4317 {
4318 unsigned int i;
4319
4320 for (i = 0; i < hist_data->n_actions; i++) {
4321 struct action_data *data = hist_data->actions[i];
4322
4323 if (data->handler == HANDLER_ONMATCH)
4324 print_onmatch_spec(m, hist_data, data);
4325 else if (data->handler == HANDLER_ONMAX ||
4326 data->handler == HANDLER_ONCHANGE)
4327 print_track_data_spec(m, hist_data, data);
4328 }
4329 }
4330
destroy_field_var_hists(struct hist_trigger_data * hist_data)4331 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4332 {
4333 unsigned int i;
4334
4335 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4336 kfree(hist_data->field_var_hists[i]->cmd);
4337 kfree(hist_data->field_var_hists[i]);
4338 }
4339 }
4340
destroy_hist_data(struct hist_trigger_data * hist_data)4341 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4342 {
4343 if (!hist_data)
4344 return;
4345
4346 destroy_hist_trigger_attrs(hist_data->attrs);
4347 destroy_hist_fields(hist_data);
4348 tracing_map_destroy(hist_data->map);
4349
4350 destroy_actions(hist_data);
4351 destroy_field_vars(hist_data);
4352 destroy_field_var_hists(hist_data);
4353
4354 kfree(hist_data);
4355 }
4356
create_tracing_map_fields(struct hist_trigger_data * hist_data)4357 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4358 {
4359 struct tracing_map *map = hist_data->map;
4360 struct ftrace_event_field *field;
4361 struct hist_field *hist_field;
4362 int i, idx = 0;
4363
4364 for_each_hist_field(i, hist_data) {
4365 hist_field = hist_data->fields[i];
4366 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4367 tracing_map_cmp_fn_t cmp_fn;
4368
4369 field = hist_field->field;
4370
4371 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4372 cmp_fn = tracing_map_cmp_none;
4373 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU)
4374 cmp_fn = tracing_map_cmp_num(hist_field->size,
4375 hist_field->is_signed);
4376 else if (is_string_field(field))
4377 cmp_fn = tracing_map_cmp_string;
4378 else
4379 cmp_fn = tracing_map_cmp_num(field->size,
4380 field->is_signed);
4381 idx = tracing_map_add_key_field(map,
4382 hist_field->offset,
4383 cmp_fn);
4384 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4385 idx = tracing_map_add_sum_field(map);
4386
4387 if (idx < 0)
4388 return idx;
4389
4390 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4391 idx = tracing_map_add_var(map);
4392 if (idx < 0)
4393 return idx;
4394 hist_field->var.idx = idx;
4395 hist_field->var.hist_data = hist_data;
4396 }
4397 }
4398
4399 return 0;
4400 }
4401
4402 static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,struct hist_trigger_attrs * attrs,struct trace_event_file * file,bool remove)4403 create_hist_data(unsigned int map_bits,
4404 struct hist_trigger_attrs *attrs,
4405 struct trace_event_file *file,
4406 bool remove)
4407 {
4408 const struct tracing_map_ops *map_ops = NULL;
4409 struct hist_trigger_data *hist_data;
4410 int ret = 0;
4411
4412 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4413 if (!hist_data)
4414 return ERR_PTR(-ENOMEM);
4415
4416 hist_data->attrs = attrs;
4417 hist_data->remove = remove;
4418 hist_data->event_file = file;
4419
4420 ret = parse_actions(hist_data);
4421 if (ret)
4422 goto free;
4423
4424 ret = create_hist_fields(hist_data, file);
4425 if (ret)
4426 goto free;
4427
4428 ret = create_sort_keys(hist_data);
4429 if (ret)
4430 goto free;
4431
4432 map_ops = &hist_trigger_elt_data_ops;
4433
4434 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
4435 map_ops, hist_data);
4436 if (IS_ERR(hist_data->map)) {
4437 ret = PTR_ERR(hist_data->map);
4438 hist_data->map = NULL;
4439 goto free;
4440 }
4441
4442 ret = create_tracing_map_fields(hist_data);
4443 if (ret)
4444 goto free;
4445 out:
4446 return hist_data;
4447 free:
4448 hist_data->attrs = NULL;
4449
4450 destroy_hist_data(hist_data);
4451
4452 hist_data = ERR_PTR(ret);
4453
4454 goto out;
4455 }
4456
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)4457 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
4458 struct tracing_map_elt *elt, void *rec,
4459 struct ring_buffer_event *rbe,
4460 u64 *var_ref_vals)
4461 {
4462 struct hist_elt_data *elt_data;
4463 struct hist_field *hist_field;
4464 unsigned int i, var_idx;
4465 u64 hist_val;
4466
4467 elt_data = elt->private_data;
4468 elt_data->var_ref_vals = var_ref_vals;
4469
4470 for_each_hist_val_field(i, hist_data) {
4471 hist_field = hist_data->fields[i];
4472 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4473 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4474 var_idx = hist_field->var.idx;
4475
4476 if (hist_field->flags & HIST_FIELD_FL_STRING) {
4477 unsigned int str_start, var_str_idx, idx;
4478 char *str, *val_str;
4479 unsigned int size;
4480
4481 str_start = hist_data->n_field_var_str +
4482 hist_data->n_save_var_str;
4483 var_str_idx = hist_field->var_str_idx;
4484 idx = str_start + var_str_idx;
4485
4486 str = elt_data->field_var_str[idx];
4487 val_str = (char *)(uintptr_t)hist_val;
4488
4489 size = min(hist_field->size, STR_VAR_LEN_MAX);
4490 strscpy(str, val_str, size);
4491
4492 hist_val = (u64)(uintptr_t)str;
4493 }
4494 tracing_map_set_var(elt, var_idx, hist_val);
4495 continue;
4496 }
4497 tracing_map_update_sum(elt, i, hist_val);
4498 }
4499
4500 for_each_hist_key_field(i, hist_data) {
4501 hist_field = hist_data->fields[i];
4502 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4503 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4504 var_idx = hist_field->var.idx;
4505 tracing_map_set_var(elt, var_idx, hist_val);
4506 }
4507 }
4508
4509 update_field_vars(hist_data, elt, rbe, rec);
4510 }
4511
add_to_key(char * compound_key,void * key,struct hist_field * key_field,void * rec)4512 static inline void add_to_key(char *compound_key, void *key,
4513 struct hist_field *key_field, void *rec)
4514 {
4515 size_t size = key_field->size;
4516
4517 if (key_field->flags & HIST_FIELD_FL_STRING) {
4518 struct ftrace_event_field *field;
4519
4520 field = key_field->field;
4521 if (field->filter_type == FILTER_DYN_STRING)
4522 size = *(u32 *)(rec + field->offset) >> 16;
4523 else if (field->filter_type == FILTER_STATIC_STRING)
4524 size = field->size;
4525
4526 /* ensure NULL-termination */
4527 if (size > key_field->size - 1)
4528 size = key_field->size - 1;
4529
4530 strncpy(compound_key + key_field->offset, (char *)key, size);
4531 } else
4532 memcpy(compound_key + key_field->offset, key, size);
4533 }
4534
4535 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)4536 hist_trigger_actions(struct hist_trigger_data *hist_data,
4537 struct tracing_map_elt *elt, void *rec,
4538 struct ring_buffer_event *rbe, void *key,
4539 u64 *var_ref_vals)
4540 {
4541 struct action_data *data;
4542 unsigned int i;
4543
4544 for (i = 0; i < hist_data->n_actions; i++) {
4545 data = hist_data->actions[i];
4546 data->fn(hist_data, elt, rec, rbe, key, data, var_ref_vals);
4547 }
4548 }
4549
event_hist_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * rbe)4550 static void event_hist_trigger(struct event_trigger_data *data, void *rec,
4551 struct ring_buffer_event *rbe)
4552 {
4553 struct hist_trigger_data *hist_data = data->private_data;
4554 bool use_compound_key = (hist_data->n_keys > 1);
4555 unsigned long entries[HIST_STACKTRACE_DEPTH];
4556 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
4557 char compound_key[HIST_KEY_SIZE_MAX];
4558 struct tracing_map_elt *elt = NULL;
4559 struct hist_field *key_field;
4560 u64 field_contents;
4561 void *key = NULL;
4562 unsigned int i;
4563
4564 memset(compound_key, 0, hist_data->key_size);
4565
4566 for_each_hist_key_field(i, hist_data) {
4567 key_field = hist_data->fields[i];
4568
4569 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4570 memset(entries, 0, HIST_STACKTRACE_SIZE);
4571 stack_trace_save(entries, HIST_STACKTRACE_DEPTH,
4572 HIST_STACKTRACE_SKIP);
4573 key = entries;
4574 } else {
4575 field_contents = key_field->fn(key_field, elt, rbe, rec);
4576 if (key_field->flags & HIST_FIELD_FL_STRING) {
4577 key = (void *)(unsigned long)field_contents;
4578 use_compound_key = true;
4579 } else
4580 key = (void *)&field_contents;
4581 }
4582
4583 if (use_compound_key)
4584 add_to_key(compound_key, key, key_field, rec);
4585 }
4586
4587 if (use_compound_key)
4588 key = compound_key;
4589
4590 if (hist_data->n_var_refs &&
4591 !resolve_var_refs(hist_data, key, var_ref_vals, false))
4592 return;
4593
4594 elt = tracing_map_insert(hist_data->map, key);
4595 if (!elt)
4596 return;
4597
4598 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
4599
4600 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
4601 hist_trigger_actions(hist_data, elt, rec, rbe, key, var_ref_vals);
4602 }
4603
hist_trigger_stacktrace_print(struct seq_file * m,unsigned long * stacktrace_entries,unsigned int max_entries)4604 static void hist_trigger_stacktrace_print(struct seq_file *m,
4605 unsigned long *stacktrace_entries,
4606 unsigned int max_entries)
4607 {
4608 char str[KSYM_SYMBOL_LEN];
4609 unsigned int spaces = 8;
4610 unsigned int i;
4611
4612 for (i = 0; i < max_entries; i++) {
4613 if (!stacktrace_entries[i])
4614 return;
4615
4616 seq_printf(m, "%*c", 1 + spaces, ' ');
4617 sprint_symbol(str, stacktrace_entries[i]);
4618 seq_printf(m, "%s\n", str);
4619 }
4620 }
4621
hist_trigger_print_key(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)4622 static void hist_trigger_print_key(struct seq_file *m,
4623 struct hist_trigger_data *hist_data,
4624 void *key,
4625 struct tracing_map_elt *elt)
4626 {
4627 struct hist_field *key_field;
4628 char str[KSYM_SYMBOL_LEN];
4629 bool multiline = false;
4630 const char *field_name;
4631 unsigned int i;
4632 u64 uval;
4633
4634 seq_puts(m, "{ ");
4635
4636 for_each_hist_key_field(i, hist_data) {
4637 key_field = hist_data->fields[i];
4638
4639 if (i > hist_data->n_vals)
4640 seq_puts(m, ", ");
4641
4642 field_name = hist_field_name(key_field, 0);
4643
4644 if (key_field->flags & HIST_FIELD_FL_HEX) {
4645 uval = *(u64 *)(key + key_field->offset);
4646 seq_printf(m, "%s: %llx", field_name, uval);
4647 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
4648 uval = *(u64 *)(key + key_field->offset);
4649 sprint_symbol_no_offset(str, uval);
4650 seq_printf(m, "%s: [%llx] %-45s", field_name,
4651 uval, str);
4652 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
4653 uval = *(u64 *)(key + key_field->offset);
4654 sprint_symbol(str, uval);
4655 seq_printf(m, "%s: [%llx] %-55s", field_name,
4656 uval, str);
4657 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
4658 struct hist_elt_data *elt_data = elt->private_data;
4659 char *comm;
4660
4661 if (WARN_ON_ONCE(!elt_data))
4662 return;
4663
4664 comm = elt_data->comm;
4665
4666 uval = *(u64 *)(key + key_field->offset);
4667 seq_printf(m, "%s: %-16s[%10llu]", field_name,
4668 comm, uval);
4669 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
4670 const char *syscall_name;
4671
4672 uval = *(u64 *)(key + key_field->offset);
4673 syscall_name = get_syscall_name(uval);
4674 if (!syscall_name)
4675 syscall_name = "unknown_syscall";
4676
4677 seq_printf(m, "%s: %-30s[%3llu]", field_name,
4678 syscall_name, uval);
4679 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4680 seq_puts(m, "stacktrace:\n");
4681 hist_trigger_stacktrace_print(m,
4682 key + key_field->offset,
4683 HIST_STACKTRACE_DEPTH);
4684 multiline = true;
4685 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
4686 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
4687 *(u64 *)(key + key_field->offset));
4688 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
4689 seq_printf(m, "%s: %-50s", field_name,
4690 (char *)(key + key_field->offset));
4691 } else {
4692 uval = *(u64 *)(key + key_field->offset);
4693 seq_printf(m, "%s: %10llu", field_name, uval);
4694 }
4695 }
4696
4697 if (!multiline)
4698 seq_puts(m, " ");
4699
4700 seq_puts(m, "}");
4701 }
4702
hist_trigger_entry_print(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)4703 static void hist_trigger_entry_print(struct seq_file *m,
4704 struct hist_trigger_data *hist_data,
4705 void *key,
4706 struct tracing_map_elt *elt)
4707 {
4708 const char *field_name;
4709 unsigned int i;
4710
4711 hist_trigger_print_key(m, hist_data, key, elt);
4712
4713 seq_printf(m, " hitcount: %10llu",
4714 tracing_map_read_sum(elt, HITCOUNT_IDX));
4715
4716 for (i = 1; i < hist_data->n_vals; i++) {
4717 field_name = hist_field_name(hist_data->fields[i], 0);
4718
4719 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
4720 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
4721 continue;
4722
4723 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
4724 seq_printf(m, " %s: %10llx", field_name,
4725 tracing_map_read_sum(elt, i));
4726 } else {
4727 seq_printf(m, " %s: %10llu", field_name,
4728 tracing_map_read_sum(elt, i));
4729 }
4730 }
4731
4732 print_actions(m, hist_data, elt);
4733
4734 seq_puts(m, "\n");
4735 }
4736
print_entries(struct seq_file * m,struct hist_trigger_data * hist_data)4737 static int print_entries(struct seq_file *m,
4738 struct hist_trigger_data *hist_data)
4739 {
4740 struct tracing_map_sort_entry **sort_entries = NULL;
4741 struct tracing_map *map = hist_data->map;
4742 int i, n_entries;
4743
4744 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
4745 hist_data->n_sort_keys,
4746 &sort_entries);
4747 if (n_entries < 0)
4748 return n_entries;
4749
4750 for (i = 0; i < n_entries; i++)
4751 hist_trigger_entry_print(m, hist_data,
4752 sort_entries[i]->key,
4753 sort_entries[i]->elt);
4754
4755 tracing_map_destroy_sort_entries(sort_entries, n_entries);
4756
4757 return n_entries;
4758 }
4759
hist_trigger_show(struct seq_file * m,struct event_trigger_data * data,int n)4760 static void hist_trigger_show(struct seq_file *m,
4761 struct event_trigger_data *data, int n)
4762 {
4763 struct hist_trigger_data *hist_data;
4764 int n_entries;
4765
4766 if (n > 0)
4767 seq_puts(m, "\n\n");
4768
4769 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4770 data->ops->print(m, data->ops, data);
4771 seq_puts(m, "#\n\n");
4772
4773 hist_data = data->private_data;
4774 n_entries = print_entries(m, hist_data);
4775 if (n_entries < 0)
4776 n_entries = 0;
4777
4778 track_data_snapshot_print(m, hist_data);
4779
4780 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
4781 (u64)atomic64_read(&hist_data->map->hits),
4782 n_entries, (u64)atomic64_read(&hist_data->map->drops));
4783 }
4784
hist_show(struct seq_file * m,void * v)4785 static int hist_show(struct seq_file *m, void *v)
4786 {
4787 struct event_trigger_data *data;
4788 struct trace_event_file *event_file;
4789 int n = 0, ret = 0;
4790
4791 mutex_lock(&event_mutex);
4792
4793 event_file = event_file_data(m->private);
4794 if (unlikely(!event_file)) {
4795 ret = -ENODEV;
4796 goto out_unlock;
4797 }
4798
4799 list_for_each_entry(data, &event_file->triggers, list) {
4800 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
4801 hist_trigger_show(m, data, n++);
4802 }
4803
4804 out_unlock:
4805 mutex_unlock(&event_mutex);
4806
4807 return ret;
4808 }
4809
event_hist_open(struct inode * inode,struct file * file)4810 static int event_hist_open(struct inode *inode, struct file *file)
4811 {
4812 int ret;
4813
4814 ret = security_locked_down(LOCKDOWN_TRACEFS);
4815 if (ret)
4816 return ret;
4817
4818 return single_open(file, hist_show, file);
4819 }
4820
4821 const struct file_operations event_hist_fops = {
4822 .open = event_hist_open,
4823 .read = seq_read,
4824 .llseek = seq_lseek,
4825 .release = single_release,
4826 };
4827
4828 #ifdef CONFIG_HIST_TRIGGERS_DEBUG
hist_field_debug_show_flags(struct seq_file * m,unsigned long flags)4829 static void hist_field_debug_show_flags(struct seq_file *m,
4830 unsigned long flags)
4831 {
4832 seq_puts(m, " flags:\n");
4833
4834 if (flags & HIST_FIELD_FL_KEY)
4835 seq_puts(m, " HIST_FIELD_FL_KEY\n");
4836 else if (flags & HIST_FIELD_FL_HITCOUNT)
4837 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n");
4838 else if (flags & HIST_FIELD_FL_VAR)
4839 seq_puts(m, " HIST_FIELD_FL_VAR\n");
4840 else if (flags & HIST_FIELD_FL_VAR_REF)
4841 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n");
4842 else
4843 seq_puts(m, " VAL: normal u64 value\n");
4844
4845 if (flags & HIST_FIELD_FL_ALIAS)
4846 seq_puts(m, " HIST_FIELD_FL_ALIAS\n");
4847 }
4848
hist_field_debug_show(struct seq_file * m,struct hist_field * field,unsigned long flags)4849 static int hist_field_debug_show(struct seq_file *m,
4850 struct hist_field *field, unsigned long flags)
4851 {
4852 if ((field->flags & flags) != flags) {
4853 seq_printf(m, "ERROR: bad flags - %lx\n", flags);
4854 return -EINVAL;
4855 }
4856
4857 hist_field_debug_show_flags(m, field->flags);
4858 if (field->field)
4859 seq_printf(m, " ftrace_event_field name: %s\n",
4860 field->field->name);
4861
4862 if (field->flags & HIST_FIELD_FL_VAR) {
4863 seq_printf(m, " var.name: %s\n", field->var.name);
4864 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4865 field->var.idx);
4866 }
4867
4868 if (field->flags & HIST_FIELD_FL_ALIAS)
4869 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
4870 field->var_ref_idx);
4871
4872 if (field->flags & HIST_FIELD_FL_VAR_REF) {
4873 seq_printf(m, " name: %s\n", field->name);
4874 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4875 field->var.idx);
4876 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data);
4877 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
4878 field->var_ref_idx);
4879 if (field->system)
4880 seq_printf(m, " system: %s\n", field->system);
4881 if (field->event_name)
4882 seq_printf(m, " event_name: %s\n", field->event_name);
4883 }
4884
4885 seq_printf(m, " type: %s\n", field->type);
4886 seq_printf(m, " size: %u\n", field->size);
4887 seq_printf(m, " is_signed: %u\n", field->is_signed);
4888
4889 return 0;
4890 }
4891
field_var_debug_show(struct seq_file * m,struct field_var * field_var,unsigned int i,bool save_vars)4892 static int field_var_debug_show(struct seq_file *m,
4893 struct field_var *field_var, unsigned int i,
4894 bool save_vars)
4895 {
4896 const char *vars_name = save_vars ? "save_vars" : "field_vars";
4897 struct hist_field *field;
4898 int ret = 0;
4899
4900 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i);
4901
4902 field = field_var->var;
4903
4904 seq_printf(m, "\n %s[%d].var:\n", vars_name, i);
4905
4906 hist_field_debug_show_flags(m, field->flags);
4907 seq_printf(m, " var.name: %s\n", field->var.name);
4908 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
4909 field->var.idx);
4910
4911 field = field_var->val;
4912
4913 seq_printf(m, "\n %s[%d].val:\n", vars_name, i);
4914 if (field->field)
4915 seq_printf(m, " ftrace_event_field name: %s\n",
4916 field->field->name);
4917 else {
4918 ret = -EINVAL;
4919 goto out;
4920 }
4921
4922 seq_printf(m, " type: %s\n", field->type);
4923 seq_printf(m, " size: %u\n", field->size);
4924 seq_printf(m, " is_signed: %u\n", field->is_signed);
4925 out:
4926 return ret;
4927 }
4928
hist_action_debug_show(struct seq_file * m,struct action_data * data,int i)4929 static int hist_action_debug_show(struct seq_file *m,
4930 struct action_data *data, int i)
4931 {
4932 int ret = 0;
4933
4934 if (data->handler == HANDLER_ONMAX ||
4935 data->handler == HANDLER_ONCHANGE) {
4936 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i);
4937 ret = hist_field_debug_show(m, data->track_data.var_ref,
4938 HIST_FIELD_FL_VAR_REF);
4939 if (ret)
4940 goto out;
4941
4942 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i);
4943 ret = hist_field_debug_show(m, data->track_data.track_var,
4944 HIST_FIELD_FL_VAR);
4945 if (ret)
4946 goto out;
4947 }
4948
4949 if (data->handler == HANDLER_ONMATCH) {
4950 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n",
4951 i, data->match_data.event_system);
4952 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n",
4953 i, data->match_data.event);
4954 }
4955 out:
4956 return ret;
4957 }
4958
hist_actions_debug_show(struct seq_file * m,struct hist_trigger_data * hist_data)4959 static int hist_actions_debug_show(struct seq_file *m,
4960 struct hist_trigger_data *hist_data)
4961 {
4962 int i, ret = 0;
4963
4964 if (hist_data->n_actions)
4965 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n");
4966
4967 for (i = 0; i < hist_data->n_actions; i++) {
4968 struct action_data *action = hist_data->actions[i];
4969
4970 ret = hist_action_debug_show(m, action, i);
4971 if (ret)
4972 goto out;
4973 }
4974
4975 if (hist_data->n_save_vars)
4976 seq_puts(m, "\n save action variables (save() params):\n");
4977
4978 for (i = 0; i < hist_data->n_save_vars; i++) {
4979 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true);
4980 if (ret)
4981 goto out;
4982 }
4983 out:
4984 return ret;
4985 }
4986
hist_trigger_debug_show(struct seq_file * m,struct event_trigger_data * data,int n)4987 static void hist_trigger_debug_show(struct seq_file *m,
4988 struct event_trigger_data *data, int n)
4989 {
4990 struct hist_trigger_data *hist_data;
4991 int i, ret;
4992
4993 if (n > 0)
4994 seq_puts(m, "\n\n");
4995
4996 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4997 data->ops->print(m, data->ops, data);
4998 seq_puts(m, "#\n\n");
4999
5000 hist_data = data->private_data;
5001
5002 seq_printf(m, "hist_data: %p\n\n", hist_data);
5003 seq_printf(m, " n_vals: %u\n", hist_data->n_vals);
5004 seq_printf(m, " n_keys: %u\n", hist_data->n_keys);
5005 seq_printf(m, " n_fields: %u\n", hist_data->n_fields);
5006
5007 seq_puts(m, "\n val fields:\n\n");
5008
5009 seq_puts(m, " hist_data->fields[0]:\n");
5010 ret = hist_field_debug_show(m, hist_data->fields[0],
5011 HIST_FIELD_FL_HITCOUNT);
5012 if (ret)
5013 return;
5014
5015 for (i = 1; i < hist_data->n_vals; i++) {
5016 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5017 ret = hist_field_debug_show(m, hist_data->fields[i], 0);
5018 if (ret)
5019 return;
5020 }
5021
5022 seq_puts(m, "\n key fields:\n");
5023
5024 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) {
5025 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5026 ret = hist_field_debug_show(m, hist_data->fields[i],
5027 HIST_FIELD_FL_KEY);
5028 if (ret)
5029 return;
5030 }
5031
5032 if (hist_data->n_var_refs)
5033 seq_puts(m, "\n variable reference fields:\n");
5034
5035 for (i = 0; i < hist_data->n_var_refs; i++) {
5036 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i);
5037 ret = hist_field_debug_show(m, hist_data->var_refs[i],
5038 HIST_FIELD_FL_VAR_REF);
5039 if (ret)
5040 return;
5041 }
5042
5043 if (hist_data->n_field_vars)
5044 seq_puts(m, "\n field variables:\n");
5045
5046 for (i = 0; i < hist_data->n_field_vars; i++) {
5047 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false);
5048 if (ret)
5049 return;
5050 }
5051
5052 ret = hist_actions_debug_show(m, hist_data);
5053 if (ret)
5054 return;
5055 }
5056
hist_debug_show(struct seq_file * m,void * v)5057 static int hist_debug_show(struct seq_file *m, void *v)
5058 {
5059 struct event_trigger_data *data;
5060 struct trace_event_file *event_file;
5061 int n = 0, ret = 0;
5062
5063 mutex_lock(&event_mutex);
5064
5065 event_file = event_file_data(m->private);
5066 if (unlikely(!event_file)) {
5067 ret = -ENODEV;
5068 goto out_unlock;
5069 }
5070
5071 list_for_each_entry(data, &event_file->triggers, list) {
5072 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5073 hist_trigger_debug_show(m, data, n++);
5074 }
5075
5076 out_unlock:
5077 mutex_unlock(&event_mutex);
5078
5079 return ret;
5080 }
5081
event_hist_debug_open(struct inode * inode,struct file * file)5082 static int event_hist_debug_open(struct inode *inode, struct file *file)
5083 {
5084 int ret;
5085
5086 ret = security_locked_down(LOCKDOWN_TRACEFS);
5087 if (ret)
5088 return ret;
5089
5090 return single_open(file, hist_debug_show, file);
5091 }
5092
5093 const struct file_operations event_hist_debug_fops = {
5094 .open = event_hist_debug_open,
5095 .read = seq_read,
5096 .llseek = seq_lseek,
5097 .release = single_release,
5098 };
5099 #endif
5100
hist_field_print(struct seq_file * m,struct hist_field * hist_field)5101 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
5102 {
5103 const char *field_name = hist_field_name(hist_field, 0);
5104
5105 if (hist_field->var.name)
5106 seq_printf(m, "%s=", hist_field->var.name);
5107
5108 if (hist_field->flags & HIST_FIELD_FL_CPU)
5109 seq_puts(m, "common_cpu");
5110 else if (field_name) {
5111 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
5112 hist_field->flags & HIST_FIELD_FL_ALIAS)
5113 seq_putc(m, '$');
5114 seq_printf(m, "%s", field_name);
5115 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
5116 seq_puts(m, "common_timestamp");
5117
5118 if (hist_field->flags) {
5119 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
5120 !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
5121 const char *flags = get_hist_field_flags(hist_field);
5122
5123 if (flags)
5124 seq_printf(m, ".%s", flags);
5125 }
5126 }
5127 }
5128
event_hist_trigger_print(struct seq_file * m,struct event_trigger_ops * ops,struct event_trigger_data * data)5129 static int event_hist_trigger_print(struct seq_file *m,
5130 struct event_trigger_ops *ops,
5131 struct event_trigger_data *data)
5132 {
5133 struct hist_trigger_data *hist_data = data->private_data;
5134 struct hist_field *field;
5135 bool have_var = false;
5136 unsigned int i;
5137
5138 seq_puts(m, "hist:");
5139
5140 if (data->name)
5141 seq_printf(m, "%s:", data->name);
5142
5143 seq_puts(m, "keys=");
5144
5145 for_each_hist_key_field(i, hist_data) {
5146 field = hist_data->fields[i];
5147
5148 if (i > hist_data->n_vals)
5149 seq_puts(m, ",");
5150
5151 if (field->flags & HIST_FIELD_FL_STACKTRACE)
5152 seq_puts(m, "stacktrace");
5153 else
5154 hist_field_print(m, field);
5155 }
5156
5157 seq_puts(m, ":vals=");
5158
5159 for_each_hist_val_field(i, hist_data) {
5160 field = hist_data->fields[i];
5161 if (field->flags & HIST_FIELD_FL_VAR) {
5162 have_var = true;
5163 continue;
5164 }
5165
5166 if (i == HITCOUNT_IDX)
5167 seq_puts(m, "hitcount");
5168 else {
5169 seq_puts(m, ",");
5170 hist_field_print(m, field);
5171 }
5172 }
5173
5174 if (have_var) {
5175 unsigned int n = 0;
5176
5177 seq_puts(m, ":");
5178
5179 for_each_hist_val_field(i, hist_data) {
5180 field = hist_data->fields[i];
5181
5182 if (field->flags & HIST_FIELD_FL_VAR) {
5183 if (n++)
5184 seq_puts(m, ",");
5185 hist_field_print(m, field);
5186 }
5187 }
5188 }
5189
5190 seq_puts(m, ":sort=");
5191
5192 for (i = 0; i < hist_data->n_sort_keys; i++) {
5193 struct tracing_map_sort_key *sort_key;
5194 unsigned int idx, first_key_idx;
5195
5196 /* skip VAR vals */
5197 first_key_idx = hist_data->n_vals - hist_data->n_vars;
5198
5199 sort_key = &hist_data->sort_keys[i];
5200 idx = sort_key->field_idx;
5201
5202 if (WARN_ON(idx >= HIST_FIELDS_MAX))
5203 return -EINVAL;
5204
5205 if (i > 0)
5206 seq_puts(m, ",");
5207
5208 if (idx == HITCOUNT_IDX)
5209 seq_puts(m, "hitcount");
5210 else {
5211 if (idx >= first_key_idx)
5212 idx += hist_data->n_vars;
5213 hist_field_print(m, hist_data->fields[idx]);
5214 }
5215
5216 if (sort_key->descending)
5217 seq_puts(m, ".descending");
5218 }
5219 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5220 if (hist_data->enable_timestamps)
5221 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5222
5223 print_actions_spec(m, hist_data);
5224
5225 if (data->filter_str)
5226 seq_printf(m, " if %s", data->filter_str);
5227
5228 if (data->paused)
5229 seq_puts(m, " [paused]");
5230 else
5231 seq_puts(m, " [active]");
5232
5233 seq_putc(m, '\n');
5234
5235 return 0;
5236 }
5237
event_hist_trigger_init(struct event_trigger_ops * ops,struct event_trigger_data * data)5238 static int event_hist_trigger_init(struct event_trigger_ops *ops,
5239 struct event_trigger_data *data)
5240 {
5241 struct hist_trigger_data *hist_data = data->private_data;
5242
5243 if (!data->ref && hist_data->attrs->name)
5244 save_named_trigger(hist_data->attrs->name, data);
5245
5246 data->ref++;
5247
5248 return 0;
5249 }
5250
unregister_field_var_hists(struct hist_trigger_data * hist_data)5251 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5252 {
5253 struct trace_event_file *file;
5254 unsigned int i;
5255 char *cmd;
5256 int ret;
5257
5258 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5259 file = hist_data->field_var_hists[i]->hist_data->event_file;
5260 cmd = hist_data->field_var_hists[i]->cmd;
5261 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
5262 "!hist", "hist", cmd);
5263 }
5264 }
5265
event_hist_trigger_free(struct event_trigger_ops * ops,struct event_trigger_data * data)5266 static void event_hist_trigger_free(struct event_trigger_ops *ops,
5267 struct event_trigger_data *data)
5268 {
5269 struct hist_trigger_data *hist_data = data->private_data;
5270
5271 if (WARN_ON_ONCE(data->ref <= 0))
5272 return;
5273
5274 data->ref--;
5275 if (!data->ref) {
5276 if (data->name)
5277 del_named_trigger(data);
5278
5279 trigger_data_free(data);
5280
5281 remove_hist_vars(hist_data);
5282
5283 unregister_field_var_hists(hist_data);
5284
5285 destroy_hist_data(hist_data);
5286 }
5287 }
5288
5289 static struct event_trigger_ops event_hist_trigger_ops = {
5290 .func = event_hist_trigger,
5291 .print = event_hist_trigger_print,
5292 .init = event_hist_trigger_init,
5293 .free = event_hist_trigger_free,
5294 };
5295
event_hist_trigger_named_init(struct event_trigger_ops * ops,struct event_trigger_data * data)5296 static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
5297 struct event_trigger_data *data)
5298 {
5299 data->ref++;
5300
5301 save_named_trigger(data->named_data->name, data);
5302
5303 event_hist_trigger_init(ops, data->named_data);
5304
5305 return 0;
5306 }
5307
event_hist_trigger_named_free(struct event_trigger_ops * ops,struct event_trigger_data * data)5308 static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
5309 struct event_trigger_data *data)
5310 {
5311 if (WARN_ON_ONCE(data->ref <= 0))
5312 return;
5313
5314 event_hist_trigger_free(ops, data->named_data);
5315
5316 data->ref--;
5317 if (!data->ref) {
5318 del_named_trigger(data);
5319 trigger_data_free(data);
5320 }
5321 }
5322
5323 static struct event_trigger_ops event_hist_trigger_named_ops = {
5324 .func = event_hist_trigger,
5325 .print = event_hist_trigger_print,
5326 .init = event_hist_trigger_named_init,
5327 .free = event_hist_trigger_named_free,
5328 };
5329
event_hist_get_trigger_ops(char * cmd,char * param)5330 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5331 char *param)
5332 {
5333 return &event_hist_trigger_ops;
5334 }
5335
hist_clear(struct event_trigger_data * data)5336 static void hist_clear(struct event_trigger_data *data)
5337 {
5338 struct hist_trigger_data *hist_data = data->private_data;
5339
5340 if (data->name)
5341 pause_named_trigger(data);
5342
5343 tracepoint_synchronize_unregister();
5344
5345 tracing_map_clear(hist_data->map);
5346
5347 if (data->name)
5348 unpause_named_trigger(data);
5349 }
5350
compatible_field(struct ftrace_event_field * field,struct ftrace_event_field * test_field)5351 static bool compatible_field(struct ftrace_event_field *field,
5352 struct ftrace_event_field *test_field)
5353 {
5354 if (field == test_field)
5355 return true;
5356 if (field == NULL || test_field == NULL)
5357 return false;
5358 if (strcmp(field->name, test_field->name) != 0)
5359 return false;
5360 if (strcmp(field->type, test_field->type) != 0)
5361 return false;
5362 if (field->size != test_field->size)
5363 return false;
5364 if (field->is_signed != test_field->is_signed)
5365 return false;
5366
5367 return true;
5368 }
5369
hist_trigger_match(struct event_trigger_data * data,struct event_trigger_data * data_test,struct event_trigger_data * named_data,bool ignore_filter)5370 static bool hist_trigger_match(struct event_trigger_data *data,
5371 struct event_trigger_data *data_test,
5372 struct event_trigger_data *named_data,
5373 bool ignore_filter)
5374 {
5375 struct tracing_map_sort_key *sort_key, *sort_key_test;
5376 struct hist_trigger_data *hist_data, *hist_data_test;
5377 struct hist_field *key_field, *key_field_test;
5378 unsigned int i;
5379
5380 if (named_data && (named_data != data_test) &&
5381 (named_data != data_test->named_data))
5382 return false;
5383
5384 if (!named_data && is_named_trigger(data_test))
5385 return false;
5386
5387 hist_data = data->private_data;
5388 hist_data_test = data_test->private_data;
5389
5390 if (hist_data->n_vals != hist_data_test->n_vals ||
5391 hist_data->n_fields != hist_data_test->n_fields ||
5392 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5393 return false;
5394
5395 if (!ignore_filter) {
5396 if ((data->filter_str && !data_test->filter_str) ||
5397 (!data->filter_str && data_test->filter_str))
5398 return false;
5399 }
5400
5401 for_each_hist_field(i, hist_data) {
5402 key_field = hist_data->fields[i];
5403 key_field_test = hist_data_test->fields[i];
5404
5405 if (key_field->flags != key_field_test->flags)
5406 return false;
5407 if (!compatible_field(key_field->field, key_field_test->field))
5408 return false;
5409 if (key_field->offset != key_field_test->offset)
5410 return false;
5411 if (key_field->size != key_field_test->size)
5412 return false;
5413 if (key_field->is_signed != key_field_test->is_signed)
5414 return false;
5415 if (!!key_field->var.name != !!key_field_test->var.name)
5416 return false;
5417 if (key_field->var.name &&
5418 strcmp(key_field->var.name, key_field_test->var.name) != 0)
5419 return false;
5420 }
5421
5422 for (i = 0; i < hist_data->n_sort_keys; i++) {
5423 sort_key = &hist_data->sort_keys[i];
5424 sort_key_test = &hist_data_test->sort_keys[i];
5425
5426 if (sort_key->field_idx != sort_key_test->field_idx ||
5427 sort_key->descending != sort_key_test->descending)
5428 return false;
5429 }
5430
5431 if (!ignore_filter && data->filter_str &&
5432 (strcmp(data->filter_str, data_test->filter_str) != 0))
5433 return false;
5434
5435 if (!actions_match(hist_data, hist_data_test))
5436 return false;
5437
5438 return true;
5439 }
5440
hist_register_trigger(char * glob,struct event_trigger_ops * ops,struct event_trigger_data * data,struct trace_event_file * file)5441 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
5442 struct event_trigger_data *data,
5443 struct trace_event_file *file)
5444 {
5445 struct hist_trigger_data *hist_data = data->private_data;
5446 struct event_trigger_data *test, *named_data = NULL;
5447 struct trace_array *tr = file->tr;
5448 int ret = 0;
5449
5450 if (hist_data->attrs->name) {
5451 named_data = find_named_trigger(hist_data->attrs->name);
5452 if (named_data) {
5453 if (!hist_trigger_match(data, named_data, named_data,
5454 true)) {
5455 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name));
5456 ret = -EINVAL;
5457 goto out;
5458 }
5459 }
5460 }
5461
5462 if (hist_data->attrs->name && !named_data)
5463 goto new;
5464
5465 lockdep_assert_held(&event_mutex);
5466
5467 list_for_each_entry(test, &file->triggers, list) {
5468 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5469 if (!hist_trigger_match(data, test, named_data, false))
5470 continue;
5471 if (hist_data->attrs->pause)
5472 test->paused = true;
5473 else if (hist_data->attrs->cont)
5474 test->paused = false;
5475 else if (hist_data->attrs->clear)
5476 hist_clear(test);
5477 else {
5478 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0);
5479 ret = -EEXIST;
5480 }
5481 goto out;
5482 }
5483 }
5484 new:
5485 if (hist_data->attrs->cont || hist_data->attrs->clear) {
5486 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0);
5487 ret = -ENOENT;
5488 goto out;
5489 }
5490
5491 if (hist_data->attrs->pause)
5492 data->paused = true;
5493
5494 if (named_data) {
5495 data->private_data = named_data->private_data;
5496 set_named_trigger_data(data, named_data);
5497 data->ops = &event_hist_trigger_named_ops;
5498 }
5499
5500 if (data->ops->init) {
5501 ret = data->ops->init(data->ops, data);
5502 if (ret < 0)
5503 goto out;
5504 }
5505
5506 if (hist_data->enable_timestamps) {
5507 char *clock = hist_data->attrs->clock;
5508
5509 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
5510 if (ret) {
5511 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock));
5512 goto out;
5513 }
5514
5515 tracing_set_time_stamp_abs(file->tr, true);
5516 }
5517
5518 if (named_data)
5519 destroy_hist_data(hist_data);
5520
5521 ret++;
5522 out:
5523 return ret;
5524 }
5525
hist_trigger_enable(struct event_trigger_data * data,struct trace_event_file * file)5526 static int hist_trigger_enable(struct event_trigger_data *data,
5527 struct trace_event_file *file)
5528 {
5529 int ret = 0;
5530
5531 list_add_tail_rcu(&data->list, &file->triggers);
5532
5533 update_cond_flag(file);
5534
5535 if (trace_event_trigger_enable_disable(file, 1) < 0) {
5536 list_del_rcu(&data->list);
5537 update_cond_flag(file);
5538 ret--;
5539 }
5540
5541 return ret;
5542 }
5543
have_hist_trigger_match(struct event_trigger_data * data,struct trace_event_file * file)5544 static bool have_hist_trigger_match(struct event_trigger_data *data,
5545 struct trace_event_file *file)
5546 {
5547 struct hist_trigger_data *hist_data = data->private_data;
5548 struct event_trigger_data *test, *named_data = NULL;
5549 bool match = false;
5550
5551 lockdep_assert_held(&event_mutex);
5552
5553 if (hist_data->attrs->name)
5554 named_data = find_named_trigger(hist_data->attrs->name);
5555
5556 list_for_each_entry(test, &file->triggers, list) {
5557 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5558 if (hist_trigger_match(data, test, named_data, false)) {
5559 match = true;
5560 break;
5561 }
5562 }
5563 }
5564
5565 return match;
5566 }
5567
hist_trigger_check_refs(struct event_trigger_data * data,struct trace_event_file * file)5568 static bool hist_trigger_check_refs(struct event_trigger_data *data,
5569 struct trace_event_file *file)
5570 {
5571 struct hist_trigger_data *hist_data = data->private_data;
5572 struct event_trigger_data *test, *named_data = NULL;
5573
5574 lockdep_assert_held(&event_mutex);
5575
5576 if (hist_data->attrs->name)
5577 named_data = find_named_trigger(hist_data->attrs->name);
5578
5579 list_for_each_entry(test, &file->triggers, list) {
5580 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5581 if (!hist_trigger_match(data, test, named_data, false))
5582 continue;
5583 hist_data = test->private_data;
5584 if (check_var_refs(hist_data))
5585 return true;
5586 break;
5587 }
5588 }
5589
5590 return false;
5591 }
5592
hist_unregister_trigger(char * glob,struct event_trigger_ops * ops,struct event_trigger_data * data,struct trace_event_file * file)5593 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
5594 struct event_trigger_data *data,
5595 struct trace_event_file *file)
5596 {
5597 struct hist_trigger_data *hist_data = data->private_data;
5598 struct event_trigger_data *test, *named_data = NULL;
5599 bool unregistered = false;
5600
5601 lockdep_assert_held(&event_mutex);
5602
5603 if (hist_data->attrs->name)
5604 named_data = find_named_trigger(hist_data->attrs->name);
5605
5606 list_for_each_entry(test, &file->triggers, list) {
5607 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5608 if (!hist_trigger_match(data, test, named_data, false))
5609 continue;
5610 unregistered = true;
5611 list_del_rcu(&test->list);
5612 trace_event_trigger_enable_disable(file, 0);
5613 update_cond_flag(file);
5614 break;
5615 }
5616 }
5617
5618 if (unregistered && test->ops->free)
5619 test->ops->free(test->ops, test);
5620
5621 if (hist_data->enable_timestamps) {
5622 if (!hist_data->remove || unregistered)
5623 tracing_set_time_stamp_abs(file->tr, false);
5624 }
5625 }
5626
hist_file_check_refs(struct trace_event_file * file)5627 static bool hist_file_check_refs(struct trace_event_file *file)
5628 {
5629 struct hist_trigger_data *hist_data;
5630 struct event_trigger_data *test;
5631
5632 lockdep_assert_held(&event_mutex);
5633
5634 list_for_each_entry(test, &file->triggers, list) {
5635 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5636 hist_data = test->private_data;
5637 if (check_var_refs(hist_data))
5638 return true;
5639 }
5640 }
5641
5642 return false;
5643 }
5644
hist_unreg_all(struct trace_event_file * file)5645 static void hist_unreg_all(struct trace_event_file *file)
5646 {
5647 struct event_trigger_data *test, *n;
5648 struct hist_trigger_data *hist_data;
5649 struct synth_event *se;
5650 const char *se_name;
5651
5652 lockdep_assert_held(&event_mutex);
5653
5654 if (hist_file_check_refs(file))
5655 return;
5656
5657 list_for_each_entry_safe(test, n, &file->triggers, list) {
5658 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5659 hist_data = test->private_data;
5660 list_del_rcu(&test->list);
5661 trace_event_trigger_enable_disable(file, 0);
5662
5663 se_name = trace_event_name(file->event_call);
5664 se = find_synth_event(se_name);
5665 if (se)
5666 se->ref--;
5667
5668 update_cond_flag(file);
5669 if (hist_data->enable_timestamps)
5670 tracing_set_time_stamp_abs(file->tr, false);
5671 if (test->ops->free)
5672 test->ops->free(test->ops, test);
5673 }
5674 }
5675 }
5676
event_hist_trigger_func(struct event_command * cmd_ops,struct trace_event_file * file,char * glob,char * cmd,char * param)5677 static int event_hist_trigger_func(struct event_command *cmd_ops,
5678 struct trace_event_file *file,
5679 char *glob, char *cmd, char *param)
5680 {
5681 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
5682 struct event_trigger_data *trigger_data;
5683 struct hist_trigger_attrs *attrs;
5684 struct event_trigger_ops *trigger_ops;
5685 struct hist_trigger_data *hist_data;
5686 struct synth_event *se;
5687 const char *se_name;
5688 bool remove = false;
5689 char *trigger, *p;
5690 int ret = 0;
5691
5692 lockdep_assert_held(&event_mutex);
5693
5694 if (glob && strlen(glob)) {
5695 hist_err_clear();
5696 last_cmd_set(file, param);
5697 }
5698
5699 if (!param)
5700 return -EINVAL;
5701
5702 if (glob[0] == '!')
5703 remove = true;
5704
5705 /*
5706 * separate the trigger from the filter (k:v [if filter])
5707 * allowing for whitespace in the trigger
5708 */
5709 p = trigger = param;
5710 do {
5711 p = strstr(p, "if");
5712 if (!p)
5713 break;
5714 if (p == param)
5715 return -EINVAL;
5716 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
5717 p++;
5718 continue;
5719 }
5720 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1)
5721 return -EINVAL;
5722 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
5723 p++;
5724 continue;
5725 }
5726 break;
5727 } while (p);
5728
5729 if (!p)
5730 param = NULL;
5731 else {
5732 *(p - 1) = '\0';
5733 param = strstrip(p);
5734 trigger = strstrip(trigger);
5735 }
5736
5737 attrs = parse_hist_trigger_attrs(file->tr, trigger);
5738 if (IS_ERR(attrs))
5739 return PTR_ERR(attrs);
5740
5741 if (attrs->map_bits)
5742 hist_trigger_bits = attrs->map_bits;
5743
5744 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
5745 if (IS_ERR(hist_data)) {
5746 destroy_hist_trigger_attrs(attrs);
5747 return PTR_ERR(hist_data);
5748 }
5749
5750 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
5751
5752 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
5753 if (!trigger_data) {
5754 ret = -ENOMEM;
5755 goto out_free;
5756 }
5757
5758 trigger_data->count = -1;
5759 trigger_data->ops = trigger_ops;
5760 trigger_data->cmd_ops = cmd_ops;
5761
5762 INIT_LIST_HEAD(&trigger_data->list);
5763 RCU_INIT_POINTER(trigger_data->filter, NULL);
5764
5765 trigger_data->private_data = hist_data;
5766
5767 /* if param is non-empty, it's supposed to be a filter */
5768 if (param && cmd_ops->set_filter) {
5769 ret = cmd_ops->set_filter(param, trigger_data, file);
5770 if (ret < 0)
5771 goto out_free;
5772 }
5773
5774 if (remove) {
5775 if (!have_hist_trigger_match(trigger_data, file))
5776 goto out_free;
5777
5778 if (hist_trigger_check_refs(trigger_data, file)) {
5779 ret = -EBUSY;
5780 goto out_free;
5781 }
5782
5783 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5784 se_name = trace_event_name(file->event_call);
5785 se = find_synth_event(se_name);
5786 if (se)
5787 se->ref--;
5788 ret = 0;
5789 goto out_free;
5790 }
5791
5792 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
5793 /*
5794 * The above returns on success the # of triggers registered,
5795 * but if it didn't register any it returns zero. Consider no
5796 * triggers registered a failure too.
5797 */
5798 if (!ret) {
5799 if (!(attrs->pause || attrs->cont || attrs->clear))
5800 ret = -ENOENT;
5801 goto out_free;
5802 } else if (ret < 0)
5803 goto out_free;
5804
5805 if (get_named_trigger_data(trigger_data))
5806 goto enable;
5807
5808 if (has_hist_vars(hist_data))
5809 save_hist_vars(hist_data);
5810
5811 ret = create_actions(hist_data);
5812 if (ret)
5813 goto out_unreg;
5814
5815 ret = tracing_map_init(hist_data->map);
5816 if (ret)
5817 goto out_unreg;
5818 enable:
5819 ret = hist_trigger_enable(trigger_data, file);
5820 if (ret)
5821 goto out_unreg;
5822
5823 se_name = trace_event_name(file->event_call);
5824 se = find_synth_event(se_name);
5825 if (se)
5826 se->ref++;
5827 /* Just return zero, not the number of registered triggers */
5828 ret = 0;
5829 out:
5830 if (ret == 0)
5831 hist_err_clear();
5832
5833 return ret;
5834 out_unreg:
5835 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5836 out_free:
5837 if (cmd_ops->set_filter)
5838 cmd_ops->set_filter(NULL, trigger_data, NULL);
5839
5840 remove_hist_vars(hist_data);
5841
5842 kfree(trigger_data);
5843
5844 destroy_hist_data(hist_data);
5845 goto out;
5846 }
5847
5848 static struct event_command trigger_hist_cmd = {
5849 .name = "hist",
5850 .trigger_type = ETT_EVENT_HIST,
5851 .flags = EVENT_CMD_FL_NEEDS_REC,
5852 .func = event_hist_trigger_func,
5853 .reg = hist_register_trigger,
5854 .unreg = hist_unregister_trigger,
5855 .unreg_all = hist_unreg_all,
5856 .get_trigger_ops = event_hist_get_trigger_ops,
5857 .set_filter = set_trigger_filter,
5858 };
5859
register_trigger_hist_cmd(void)5860 __init int register_trigger_hist_cmd(void)
5861 {
5862 int ret;
5863
5864 ret = register_event_command(&trigger_hist_cmd);
5865 WARN_ON(ret < 0);
5866
5867 return ret;
5868 }
5869
5870 static void
hist_enable_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * event)5871 hist_enable_trigger(struct event_trigger_data *data, void *rec,
5872 struct ring_buffer_event *event)
5873 {
5874 struct enable_trigger_data *enable_data = data->private_data;
5875 struct event_trigger_data *test;
5876
5877 list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
5878 lockdep_is_held(&event_mutex)) {
5879 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5880 if (enable_data->enable)
5881 test->paused = false;
5882 else
5883 test->paused = true;
5884 }
5885 }
5886 }
5887
5888 static void
hist_enable_count_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * event)5889 hist_enable_count_trigger(struct event_trigger_data *data, void *rec,
5890 struct ring_buffer_event *event)
5891 {
5892 if (!data->count)
5893 return;
5894
5895 if (data->count != -1)
5896 (data->count)--;
5897
5898 hist_enable_trigger(data, rec, event);
5899 }
5900
5901 static struct event_trigger_ops hist_enable_trigger_ops = {
5902 .func = hist_enable_trigger,
5903 .print = event_enable_trigger_print,
5904 .init = event_trigger_init,
5905 .free = event_enable_trigger_free,
5906 };
5907
5908 static struct event_trigger_ops hist_enable_count_trigger_ops = {
5909 .func = hist_enable_count_trigger,
5910 .print = event_enable_trigger_print,
5911 .init = event_trigger_init,
5912 .free = event_enable_trigger_free,
5913 };
5914
5915 static struct event_trigger_ops hist_disable_trigger_ops = {
5916 .func = hist_enable_trigger,
5917 .print = event_enable_trigger_print,
5918 .init = event_trigger_init,
5919 .free = event_enable_trigger_free,
5920 };
5921
5922 static struct event_trigger_ops hist_disable_count_trigger_ops = {
5923 .func = hist_enable_count_trigger,
5924 .print = event_enable_trigger_print,
5925 .init = event_trigger_init,
5926 .free = event_enable_trigger_free,
5927 };
5928
5929 static struct event_trigger_ops *
hist_enable_get_trigger_ops(char * cmd,char * param)5930 hist_enable_get_trigger_ops(char *cmd, char *param)
5931 {
5932 struct event_trigger_ops *ops;
5933 bool enable;
5934
5935 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
5936
5937 if (enable)
5938 ops = param ? &hist_enable_count_trigger_ops :
5939 &hist_enable_trigger_ops;
5940 else
5941 ops = param ? &hist_disable_count_trigger_ops :
5942 &hist_disable_trigger_ops;
5943
5944 return ops;
5945 }
5946
hist_enable_unreg_all(struct trace_event_file * file)5947 static void hist_enable_unreg_all(struct trace_event_file *file)
5948 {
5949 struct event_trigger_data *test, *n;
5950
5951 list_for_each_entry_safe(test, n, &file->triggers, list) {
5952 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
5953 list_del_rcu(&test->list);
5954 update_cond_flag(file);
5955 trace_event_trigger_enable_disable(file, 0);
5956 if (test->ops->free)
5957 test->ops->free(test->ops, test);
5958 }
5959 }
5960 }
5961
5962 static struct event_command trigger_hist_enable_cmd = {
5963 .name = ENABLE_HIST_STR,
5964 .trigger_type = ETT_HIST_ENABLE,
5965 .func = event_enable_trigger_func,
5966 .reg = event_enable_register_trigger,
5967 .unreg = event_enable_unregister_trigger,
5968 .unreg_all = hist_enable_unreg_all,
5969 .get_trigger_ops = hist_enable_get_trigger_ops,
5970 .set_filter = set_trigger_filter,
5971 };
5972
5973 static struct event_command trigger_hist_disable_cmd = {
5974 .name = DISABLE_HIST_STR,
5975 .trigger_type = ETT_HIST_ENABLE,
5976 .func = event_enable_trigger_func,
5977 .reg = event_enable_register_trigger,
5978 .unreg = event_enable_unregister_trigger,
5979 .unreg_all = hist_enable_unreg_all,
5980 .get_trigger_ops = hist_enable_get_trigger_ops,
5981 .set_filter = set_trigger_filter,
5982 };
5983
unregister_trigger_hist_enable_disable_cmds(void)5984 static __init void unregister_trigger_hist_enable_disable_cmds(void)
5985 {
5986 unregister_event_command(&trigger_hist_enable_cmd);
5987 unregister_event_command(&trigger_hist_disable_cmd);
5988 }
5989
register_trigger_hist_enable_disable_cmds(void)5990 __init int register_trigger_hist_enable_disable_cmds(void)
5991 {
5992 int ret;
5993
5994 ret = register_event_command(&trigger_hist_enable_cmd);
5995 if (WARN_ON(ret < 0))
5996 return ret;
5997 ret = register_event_command(&trigger_hist_disable_cmd);
5998 if (WARN_ON(ret < 0))
5999 unregister_trigger_hist_enable_disable_cmds();
6000
6001 return ret;
6002 }
6003