?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
accel/amdxdna: use modern PM helpers
[drm/drm-misc.git] / kernel / trace / trace_events_hist.c
blob9c058aa8baf332a51d3fc771a4dff97e62d04162
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 C(EXPECT_NUMBER, "Expecting numeric literal"), \
71 C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \
72 C(DIVISION_BY_ZERO, "Division by zero"), \
73 C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"),
74
75 #undef C
76 #define C(a, b) HIST_ERR_##a
77
78 enum { ERRORS };
79
80 #undef C
81 #define C(a, b) b
82
83 static const char *err_text[] = { ERRORS };
84
85 struct hist_field;
86
87 typedef u64 (*hist_field_fn_t) (struct hist_field *field,
88 struct tracing_map_elt *elt,
89 struct trace_buffer *buffer,
90 struct ring_buffer_event *rbe,
91 void *event);
92
93 #define HIST_FIELD_OPERANDS_MAX 2
94 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
95 #define HIST_ACTIONS_MAX 8
96 #define HIST_CONST_DIGITS_MAX 21
97 #define HIST_DIV_SHIFT 20 /* For optimizing division by constants */
98
99 enum field_op_id {
100 FIELD_OP_NONE,
101 FIELD_OP_PLUS,
102 FIELD_OP_MINUS,
103 FIELD_OP_UNARY_MINUS,
104 FIELD_OP_DIV,
105 FIELD_OP_MULT,
106 };
107
108 enum hist_field_fn {
109 HIST_FIELD_FN_NOP,
110 HIST_FIELD_FN_VAR_REF,
111 HIST_FIELD_FN_COUNTER,
112 HIST_FIELD_FN_CONST,
113 HIST_FIELD_FN_LOG2,
114 HIST_FIELD_FN_BUCKET,
115 HIST_FIELD_FN_TIMESTAMP,
116 HIST_FIELD_FN_CPU,
117 HIST_FIELD_FN_STRING,
118 HIST_FIELD_FN_DYNSTRING,
119 HIST_FIELD_FN_RELDYNSTRING,
120 HIST_FIELD_FN_PSTRING,
121 HIST_FIELD_FN_S64,
122 HIST_FIELD_FN_U64,
123 HIST_FIELD_FN_S32,
124 HIST_FIELD_FN_U32,
125 HIST_FIELD_FN_S16,
126 HIST_FIELD_FN_U16,
127 HIST_FIELD_FN_S8,
128 HIST_FIELD_FN_U8,
129 HIST_FIELD_FN_UMINUS,
130 HIST_FIELD_FN_MINUS,
131 HIST_FIELD_FN_PLUS,
132 HIST_FIELD_FN_DIV,
133 HIST_FIELD_FN_MULT,
134 HIST_FIELD_FN_DIV_POWER2,
135 HIST_FIELD_FN_DIV_NOT_POWER2,
136 HIST_FIELD_FN_DIV_MULT_SHIFT,
137 HIST_FIELD_FN_EXECNAME,
138 HIST_FIELD_FN_STACK,
139 };
140
141 /*
142 * A hist_var (histogram variable) contains variable information for
143 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF
144 * flag set. A hist_var has a variable name e.g. ts0, and is
145 * associated with a given histogram trigger, as specified by
146 * hist_data. The hist_var idx is the unique index assigned to the
147 * variable by the hist trigger's tracing_map. The idx is what is
148 * used to set a variable's value and, by a variable reference, to
149 * retrieve it.
150 */
151 struct hist_var {
152 char *name;
153 struct hist_trigger_data *hist_data;
154 unsigned int idx;
155 };
156
157 struct hist_field {
158 struct ftrace_event_field *field;
159 unsigned long flags;
160 unsigned long buckets;
161 const char *type;
162 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
163 struct hist_trigger_data *hist_data;
164 enum hist_field_fn fn_num;
165 unsigned int ref;
166 unsigned int size;
167 unsigned int offset;
168 unsigned int is_signed;
169
170 /*
171 * Variable fields contain variable-specific info in var.
172 */
173 struct hist_var var;
174 enum field_op_id operator;
175 char *system;
176 char *event_name;
177
178 /*
179 * The name field is used for EXPR and VAR_REF fields. VAR
180 * fields contain the variable name in var.name.
181 */
182 char *name;
183
184 /*
185 * When a histogram trigger is hit, if it has any references
186 * to variables, the values of those variables are collected
187 * into a var_ref_vals array by resolve_var_refs(). The
188 * current value of each variable is read from the tracing_map
189 * using the hist field's hist_var.idx and entered into the
190 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx].
191 */
192 unsigned int var_ref_idx;
193 bool read_once;
194
195 unsigned int var_str_idx;
196
197 /* Numeric literals are represented as u64 */
198 u64 constant;
199 /* Used to optimize division by constants */
200 u64 div_multiplier;
201 };
202
203 static u64 hist_fn_call(struct hist_field *hist_field,
204 struct tracing_map_elt *elt,
205 struct trace_buffer *buffer,
206 struct ring_buffer_event *rbe,
207 void *event);
208
209 static u64 hist_field_const(struct hist_field *field,
210 struct tracing_map_elt *elt,
211 struct trace_buffer *buffer,
212 struct ring_buffer_event *rbe,
213 void *event)
214 {
215 return field->constant;
216 }
217
218 static u64 hist_field_counter(struct hist_field *field,
219 struct tracing_map_elt *elt,
220 struct trace_buffer *buffer,
221 struct ring_buffer_event *rbe,
222 void *event)
223 {
224 return 1;
225 }
226
227 static u64 hist_field_string(struct hist_field *hist_field,
228 struct tracing_map_elt *elt,
229 struct trace_buffer *buffer,
230 struct ring_buffer_event *rbe,
231 void *event)
232 {
233 char *addr = (char *)(event + hist_field->field->offset);
234
235 return (u64)(unsigned long)addr;
236 }
237
238 static u64 hist_field_dynstring(struct hist_field *hist_field,
239 struct tracing_map_elt *elt,
240 struct trace_buffer *buffer,
241 struct ring_buffer_event *rbe,
242 void *event)
243 {
244 u32 str_item = *(u32 *)(event + hist_field->field->offset);
245 int str_loc = str_item & 0xffff;
246 char *addr = (char *)(event + str_loc);
247
248 return (u64)(unsigned long)addr;
249 }
250
251 static u64 hist_field_reldynstring(struct hist_field *hist_field,
252 struct tracing_map_elt *elt,
253 struct trace_buffer *buffer,
254 struct ring_buffer_event *rbe,
255 void *event)
256 {
257 u32 *item = event + hist_field->field->offset;
258 u32 str_item = *item;
259 int str_loc = str_item & 0xffff;
260 char *addr = (char *)&item[1] + str_loc;
261
262 return (u64)(unsigned long)addr;
263 }
264
265 static u64 hist_field_pstring(struct hist_field *hist_field,
266 struct tracing_map_elt *elt,
267 struct trace_buffer *buffer,
268 struct ring_buffer_event *rbe,
269 void *event)
270 {
271 char **addr = (char **)(event + hist_field->field->offset);
272
273 return (u64)(unsigned long)*addr;
274 }
275
276 static u64 hist_field_log2(struct hist_field *hist_field,
277 struct tracing_map_elt *elt,
278 struct trace_buffer *buffer,
279 struct ring_buffer_event *rbe,
280 void *event)
281 {
282 struct hist_field *operand = hist_field->operands[0];
283
284 u64 val = hist_fn_call(operand, elt, buffer, rbe, event);
285
286 return (u64) ilog2(roundup_pow_of_two(val));
287 }
288
289 static u64 hist_field_bucket(struct hist_field *hist_field,
290 struct tracing_map_elt *elt,
291 struct trace_buffer *buffer,
292 struct ring_buffer_event *rbe,
293 void *event)
294 {
295 struct hist_field *operand = hist_field->operands[0];
296 unsigned long buckets = hist_field->buckets;
297
298 u64 val = hist_fn_call(operand, elt, buffer, rbe, event);
299
300 if (WARN_ON_ONCE(!buckets))
301 return val;
302
303 if (val >= LONG_MAX)
304 val = div64_ul(val, buckets);
305 else
306 val = (u64)((unsigned long)val / buckets);
307 return val * buckets;
308 }
309
310 static u64 hist_field_plus(struct hist_field *hist_field,
311 struct tracing_map_elt *elt,
312 struct trace_buffer *buffer,
313 struct ring_buffer_event *rbe,
314 void *event)
315 {
316 struct hist_field *operand1 = hist_field->operands[0];
317 struct hist_field *operand2 = hist_field->operands[1];
318
319 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
320 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
321
322 return val1 + val2;
323 }
324
325 static u64 hist_field_minus(struct hist_field *hist_field,
326 struct tracing_map_elt *elt,
327 struct trace_buffer *buffer,
328 struct ring_buffer_event *rbe,
329 void *event)
330 {
331 struct hist_field *operand1 = hist_field->operands[0];
332 struct hist_field *operand2 = hist_field->operands[1];
333
334 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
335 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
336
337 return val1 - val2;
338 }
339
340 static u64 hist_field_div(struct hist_field *hist_field,
341 struct tracing_map_elt *elt,
342 struct trace_buffer *buffer,
343 struct ring_buffer_event *rbe,
344 void *event)
345 {
346 struct hist_field *operand1 = hist_field->operands[0];
347 struct hist_field *operand2 = hist_field->operands[1];
348
349 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
350 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
351
352 /* Return -1 for the undefined case */
353 if (!val2)
354 return -1;
355
356 /* Use shift if the divisor is a power of 2 */
357 if (!(val2 & (val2 - 1)))
358 return val1 >> __ffs64(val2);
359
360 return div64_u64(val1, val2);
361 }
362
363 static u64 div_by_power_of_two(struct hist_field *hist_field,
364 struct tracing_map_elt *elt,
365 struct trace_buffer *buffer,
366 struct ring_buffer_event *rbe,
367 void *event)
368 {
369 struct hist_field *operand1 = hist_field->operands[0];
370 struct hist_field *operand2 = hist_field->operands[1];
371
372 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
373
374 return val1 >> __ffs64(operand2->constant);
375 }
376
377 static u64 div_by_not_power_of_two(struct hist_field *hist_field,
378 struct tracing_map_elt *elt,
379 struct trace_buffer *buffer,
380 struct ring_buffer_event *rbe,
381 void *event)
382 {
383 struct hist_field *operand1 = hist_field->operands[0];
384 struct hist_field *operand2 = hist_field->operands[1];
385
386 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
387
388 return div64_u64(val1, operand2->constant);
389 }
390
391 static u64 div_by_mult_and_shift(struct hist_field *hist_field,
392 struct tracing_map_elt *elt,
393 struct trace_buffer *buffer,
394 struct ring_buffer_event *rbe,
395 void *event)
396 {
397 struct hist_field *operand1 = hist_field->operands[0];
398 struct hist_field *operand2 = hist_field->operands[1];
399
400 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
401
402 /*
403 * If the divisor is a constant, do a multiplication and shift instead.
404 *
405 * Choose Z = some power of 2. If Y <= Z, then:
406 * X / Y = (X * (Z / Y)) / Z
407 *
408 * (Z / Y) is a constant (mult) which is calculated at parse time, so:
409 * X / Y = (X * mult) / Z
410 *
411 * The division by Z can be replaced by a shift since Z is a power of 2:
412 * X / Y = (X * mult) >> HIST_DIV_SHIFT
413 *
414 * As long, as X < Z the results will not be off by more than 1.
415 */
416 if (val1 < (1 << HIST_DIV_SHIFT)) {
417 u64 mult = operand2->div_multiplier;
418
419 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT;
420 }
421
422 return div64_u64(val1, operand2->constant);
423 }
424
425 static u64 hist_field_mult(struct hist_field *hist_field,
426 struct tracing_map_elt *elt,
427 struct trace_buffer *buffer,
428 struct ring_buffer_event *rbe,
429 void *event)
430 {
431 struct hist_field *operand1 = hist_field->operands[0];
432 struct hist_field *operand2 = hist_field->operands[1];
433
434 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
435 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
436
437 return val1 * val2;
438 }
439
440 static u64 hist_field_unary_minus(struct hist_field *hist_field,
441 struct tracing_map_elt *elt,
442 struct trace_buffer *buffer,
443 struct ring_buffer_event *rbe,
444 void *event)
445 {
446 struct hist_field *operand = hist_field->operands[0];
447
448 s64 sval = (s64)hist_fn_call(operand, elt, buffer, rbe, event);
449 u64 val = (u64)-sval;
450
451 return val;
452 }
453
454 #define DEFINE_HIST_FIELD_FN(type) \
455 static u64 hist_field_##type(struct hist_field *hist_field, \
456 struct tracing_map_elt *elt, \
457 struct trace_buffer *buffer, \
458 struct ring_buffer_event *rbe, \
459 void *event) \
460 { \
461 type *addr = (type *)(event + hist_field->field->offset); \
462 \
463 return (u64)(unsigned long)*addr; \
464 }
465
466 DEFINE_HIST_FIELD_FN(s64);
467 DEFINE_HIST_FIELD_FN(u64);
468 DEFINE_HIST_FIELD_FN(s32);
469 DEFINE_HIST_FIELD_FN(u32);
470 DEFINE_HIST_FIELD_FN(s16);
471 DEFINE_HIST_FIELD_FN(u16);
472 DEFINE_HIST_FIELD_FN(s8);
473 DEFINE_HIST_FIELD_FN(u8);
474
475 #define for_each_hist_field(i, hist_data) \
476 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
477
478 #define for_each_hist_val_field(i, hist_data) \
479 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
480
481 #define for_each_hist_key_field(i, hist_data) \
482 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
483
484 #define HITCOUNT_IDX 0
485 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
486
487 enum hist_field_flags {
488 HIST_FIELD_FL_HITCOUNT = 1 << 0,
489 HIST_FIELD_FL_KEY = 1 << 1,
490 HIST_FIELD_FL_STRING = 1 << 2,
491 HIST_FIELD_FL_HEX = 1 << 3,
492 HIST_FIELD_FL_SYM = 1 << 4,
493 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
494 HIST_FIELD_FL_EXECNAME = 1 << 6,
495 HIST_FIELD_FL_SYSCALL = 1 << 7,
496 HIST_FIELD_FL_STACKTRACE = 1 << 8,
497 HIST_FIELD_FL_LOG2 = 1 << 9,
498 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
499 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
500 HIST_FIELD_FL_VAR = 1 << 12,
501 HIST_FIELD_FL_EXPR = 1 << 13,
502 HIST_FIELD_FL_VAR_REF = 1 << 14,
503 HIST_FIELD_FL_CPU = 1 << 15,
504 HIST_FIELD_FL_ALIAS = 1 << 16,
505 HIST_FIELD_FL_BUCKET = 1 << 17,
506 HIST_FIELD_FL_CONST = 1 << 18,
507 HIST_FIELD_FL_PERCENT = 1 << 19,
508 HIST_FIELD_FL_GRAPH = 1 << 20,
509 };
510
511 struct var_defs {
512 unsigned int n_vars;
513 char *name[TRACING_MAP_VARS_MAX];
514 char *expr[TRACING_MAP_VARS_MAX];
515 };
516
517 struct hist_trigger_attrs {
518 char *keys_str;
519 char *vals_str;
520 char *sort_key_str;
521 char *name;
522 char *clock;
523 bool pause;
524 bool cont;
525 bool clear;
526 bool ts_in_usecs;
527 bool no_hitcount;
528 unsigned int map_bits;
529
530 char *assignment_str[TRACING_MAP_VARS_MAX];
531 unsigned int n_assignments;
532
533 char *action_str[HIST_ACTIONS_MAX];
534 unsigned int n_actions;
535
536 struct var_defs var_defs;
537 };
538
539 struct field_var {
540 struct hist_field *var;
541 struct hist_field *val;
542 };
543
544 struct field_var_hist {
545 struct hist_trigger_data *hist_data;
546 char *cmd;
547 };
548
549 struct hist_trigger_data {
550 struct hist_field *fields[HIST_FIELDS_MAX];
551 unsigned int n_vals;
552 unsigned int n_keys;
553 unsigned int n_fields;
554 unsigned int n_vars;
555 unsigned int n_var_str;
556 unsigned int key_size;
557 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
558 unsigned int n_sort_keys;
559 struct trace_event_file *event_file;
560 struct hist_trigger_attrs *attrs;
561 struct tracing_map *map;
562 bool enable_timestamps;
563 bool remove;
564 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
565 unsigned int n_var_refs;
566
567 struct action_data *actions[HIST_ACTIONS_MAX];
568 unsigned int n_actions;
569
570 struct field_var *field_vars[SYNTH_FIELDS_MAX];
571 unsigned int n_field_vars;
572 unsigned int n_field_var_str;
573 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
574 unsigned int n_field_var_hists;
575
576 struct field_var *save_vars[SYNTH_FIELDS_MAX];
577 unsigned int n_save_vars;
578 unsigned int n_save_var_str;
579 };
580
581 struct action_data;
582
583 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
584 struct tracing_map_elt *elt,
585 struct trace_buffer *buffer, void *rec,
586 struct ring_buffer_event *rbe, void *key,
587 struct action_data *data, u64 *var_ref_vals);
588
589 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val);
590
591 enum handler_id {
592 HANDLER_ONMATCH = 1,
593 HANDLER_ONMAX,
594 HANDLER_ONCHANGE,
595 };
596
597 enum action_id {
598 ACTION_SAVE = 1,
599 ACTION_TRACE,
600 ACTION_SNAPSHOT,
601 };
602
603 struct action_data {
604 enum handler_id handler;
605 enum action_id action;
606 char *action_name;
607 action_fn_t fn;
608
609 unsigned int n_params;
610 char *params[SYNTH_FIELDS_MAX];
611
612 /*
613 * When a histogram trigger is hit, the values of any
614 * references to variables, including variables being passed
615 * as parameters to synthetic events, are collected into a
616 * var_ref_vals array. This var_ref_idx array is an array of
617 * indices into the var_ref_vals array, one for each synthetic
618 * event param, and is passed to the synthetic event
619 * invocation.
620 */
621 unsigned int var_ref_idx[SYNTH_FIELDS_MAX];
622 struct synth_event *synth_event;
623 bool use_trace_keyword;
624 char *synth_event_name;
625
626 union {
627 struct {
628 char *event;
629 char *event_system;
630 } match_data;
631
632 struct {
633 /*
634 * var_str contains the $-unstripped variable
635 * name referenced by var_ref, and used when
636 * printing the action. Because var_ref
637 * creation is deferred to create_actions(),
638 * we need a per-action way to save it until
639 * then, thus var_str.
640 */
641 char *var_str;
642
643 /*
644 * var_ref refers to the variable being
645 * tracked e.g onmax($var).
646 */
647 struct hist_field *var_ref;
648
649 /*
650 * track_var contains the 'invisible' tracking
651 * variable created to keep the current
652 * e.g. max value.
653 */
654 struct hist_field *track_var;
655
656 check_track_val_fn_t check_val;
657 action_fn_t save_data;
658 } track_data;
659 };
660 };
661
662 struct track_data {
663 u64 track_val;
664 bool updated;
665
666 unsigned int key_len;
667 void *key;
668 struct tracing_map_elt elt;
669
670 struct action_data *action_data;
671 struct hist_trigger_data *hist_data;
672 };
673
674 struct hist_elt_data {
675 char *comm;
676 u64 *var_ref_vals;
677 char **field_var_str;
678 int n_field_var_str;
679 };
680
681 struct snapshot_context {
682 struct tracing_map_elt *elt;
683 void *key;
684 };
685
686 /*
687 * Returns the specific division function to use if the divisor
688 * is constant. This avoids extra branches when the trigger is hit.
689 */
690 static enum hist_field_fn hist_field_get_div_fn(struct hist_field *divisor)
691 {
692 u64 div = divisor->constant;
693
694 if (!(div & (div - 1)))
695 return HIST_FIELD_FN_DIV_POWER2;
696
697 /* If the divisor is too large, do a regular division */
698 if (div > (1 << HIST_DIV_SHIFT))
699 return HIST_FIELD_FN_DIV_NOT_POWER2;
700
701 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div);
702 return HIST_FIELD_FN_DIV_MULT_SHIFT;
703 }
704
705 static void track_data_free(struct track_data *track_data)
706 {
707 struct hist_elt_data *elt_data;
708
709 if (!track_data)
710 return;
711
712 kfree(track_data->key);
713
714 elt_data = track_data->elt.private_data;
715 if (elt_data) {
716 kfree(elt_data->comm);
717 kfree(elt_data);
718 }
719
720 kfree(track_data);
721 }
722
723 static struct track_data *track_data_alloc(unsigned int key_len,
724 struct action_data *action_data,
725 struct hist_trigger_data *hist_data)
726 {
727 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
728 struct hist_elt_data *elt_data;
729
730 if (!data)
731 return ERR_PTR(-ENOMEM);
732
733 data->key = kzalloc(key_len, GFP_KERNEL);
734 if (!data->key) {
735 track_data_free(data);
736 return ERR_PTR(-ENOMEM);
737 }
738
739 data->key_len = key_len;
740 data->action_data = action_data;
741 data->hist_data = hist_data;
742
743 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
744 if (!elt_data) {
745 track_data_free(data);
746 return ERR_PTR(-ENOMEM);
747 }
748
749 data->elt.private_data = elt_data;
750
751 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL);
752 if (!elt_data->comm) {
753 track_data_free(data);
754 return ERR_PTR(-ENOMEM);
755 }
756
757 return data;
758 }
759
760 #define HIST_PREFIX "hist:"
761
762 static char *last_cmd;
763 static char last_cmd_loc[MAX_FILTER_STR_VAL];
764
765 static int errpos(char *str)
766 {
767 if (!str || !last_cmd)
768 return 0;
769
770 return err_pos(last_cmd, str);
771 }
772
773 static void last_cmd_set(struct trace_event_file *file, char *str)
774 {
775 const char *system = NULL, *name = NULL;
776 struct trace_event_call *call;
777
778 if (!str)
779 return;
780
781 kfree(last_cmd);
782
783 last_cmd = kasprintf(GFP_KERNEL, HIST_PREFIX "%s", str);
784 if (!last_cmd)
785 return;
786
787 if (file) {
788 call = file->event_call;
789 system = call->class->system;
790 if (system) {
791 name = trace_event_name(call);
792 if (!name)
793 system = NULL;
794 }
795 }
796
797 if (system)
798 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name);
799 }
800
801 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos)
802 {
803 if (!last_cmd)
804 return;
805
806 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,
807 err_type, err_pos);
808 }
809
810 static void hist_err_clear(void)
811 {
812 if (last_cmd)
813 last_cmd[0] = '\0';
814 last_cmd_loc[0] = '\0';
815 }
816
817 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
818 unsigned int *var_ref_idx);
819
820 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
821 unsigned int *var_ref_idx)
822 {
823 struct tracepoint *tp = event->tp;
824
825 if (unlikely(static_key_enabled(&tp->key))) {
826 struct tracepoint_func *probe_func_ptr;
827 synth_probe_func_t probe_func;
828 void *__data;
829
830 if (!(cpu_online(raw_smp_processor_id())))
831 return;
832
833 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
834 if (probe_func_ptr) {
835 do {
836 probe_func = probe_func_ptr->func;
837 __data = probe_func_ptr->data;
838 probe_func(__data, var_ref_vals, var_ref_idx);
839 } while ((++probe_func_ptr)->func);
840 }
841 }
842 }
843
844 static void action_trace(struct hist_trigger_data *hist_data,
845 struct tracing_map_elt *elt,
846 struct trace_buffer *buffer, void *rec,
847 struct ring_buffer_event *rbe, void *key,
848 struct action_data *data, u64 *var_ref_vals)
849 {
850 struct synth_event *event = data->synth_event;
851
852 trace_synth(event, var_ref_vals, data->var_ref_idx);
853 }
854
855 struct hist_var_data {
856 struct list_head list;
857 struct hist_trigger_data *hist_data;
858 };
859
860 static u64 hist_field_timestamp(struct hist_field *hist_field,
861 struct tracing_map_elt *elt,
862 struct trace_buffer *buffer,
863 struct ring_buffer_event *rbe,
864 void *event)
865 {
866 struct hist_trigger_data *hist_data = hist_field->hist_data;
867 struct trace_array *tr = hist_data->event_file->tr;
868
869 u64 ts = ring_buffer_event_time_stamp(buffer, rbe);
870
871 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
872 ts = ns2usecs(ts);
873
874 return ts;
875 }
876
877 static u64 hist_field_cpu(struct hist_field *hist_field,
878 struct tracing_map_elt *elt,
879 struct trace_buffer *buffer,
880 struct ring_buffer_event *rbe,
881 void *event)
882 {
883 int cpu = smp_processor_id();
884
885 return cpu;
886 }
887
888 /**
889 * check_field_for_var_ref - Check if a VAR_REF field references a variable
890 * @hist_field: The VAR_REF field to check
891 * @var_data: The hist trigger that owns the variable
892 * @var_idx: The trigger variable identifier
893 *
894 * Check the given VAR_REF field to see whether or not it references
895 * the given variable associated with the given trigger.
896 *
897 * Return: The VAR_REF field if it does reference the variable, NULL if not
898 */
899 static struct hist_field *
900 check_field_for_var_ref(struct hist_field *hist_field,
901 struct hist_trigger_data *var_data,
902 unsigned int var_idx)
903 {
904 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF));
905
906 if (hist_field && hist_field->var.idx == var_idx &&
907 hist_field->var.hist_data == var_data)
908 return hist_field;
909
910 return NULL;
911 }
912
913 /**
914 * find_var_ref - Check if a trigger has a reference to a trigger variable
915 * @hist_data: The hist trigger that might have a reference to the variable
916 * @var_data: The hist trigger that owns the variable
917 * @var_idx: The trigger variable identifier
918 *
919 * Check the list of var_refs[] on the first hist trigger to see
920 * whether any of them are references to the variable on the second
921 * trigger.
922 *
923 * Return: The VAR_REF field referencing the variable if so, NULL if not
924 */
925 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
926 struct hist_trigger_data *var_data,
927 unsigned int var_idx)
928 {
929 struct hist_field *hist_field;
930 unsigned int i;
931
932 for (i = 0; i < hist_data->n_var_refs; i++) {
933 hist_field = hist_data->var_refs[i];
934 if (check_field_for_var_ref(hist_field, var_data, var_idx))
935 return hist_field;
936 }
937
938 return NULL;
939 }
940
941 /**
942 * find_any_var_ref - Check if there is a reference to a given trigger variable
943 * @hist_data: The hist trigger
944 * @var_idx: The trigger variable identifier
945 *
946 * Check to see whether the given variable is currently referenced by
947 * any other trigger.
948 *
949 * The trigger the variable is defined on is explicitly excluded - the
950 * assumption being that a self-reference doesn't prevent a trigger
951 * from being removed.
952 *
953 * Return: The VAR_REF field referencing the variable if so, NULL if not
954 */
955 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
956 unsigned int var_idx)
957 {
958 struct trace_array *tr = hist_data->event_file->tr;
959 struct hist_field *found = NULL;
960 struct hist_var_data *var_data;
961
962 list_for_each_entry(var_data, &tr->hist_vars, list) {
963 if (var_data->hist_data == hist_data)
964 continue;
965 found = find_var_ref(var_data->hist_data, hist_data, var_idx);
966 if (found)
967 break;
968 }
969
970 return found;
971 }
972
973 /**
974 * check_var_refs - Check if there is a reference to any of trigger's variables
975 * @hist_data: The hist trigger
976 *
977 * A trigger can define one or more variables. If any one of them is
978 * currently referenced by any other trigger, this function will
979 * determine that.
980 *
981 * Typically used to determine whether or not a trigger can be removed
982 * - if there are any references to a trigger's variables, it cannot.
983 *
984 * Return: True if there is a reference to any of trigger's variables
985 */
986 static bool check_var_refs(struct hist_trigger_data *hist_data)
987 {
988 struct hist_field *field;
989 bool found = false;
990 int i;
991
992 for_each_hist_field(i, hist_data) {
993 field = hist_data->fields[i];
994 if (field && field->flags & HIST_FIELD_FL_VAR) {
995 if (find_any_var_ref(hist_data, field->var.idx)) {
996 found = true;
997 break;
998 }
999 }
1000 }
1001
1002 return found;
1003 }
1004
1005 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
1006 {
1007 struct trace_array *tr = hist_data->event_file->tr;
1008 struct hist_var_data *var_data, *found = NULL;
1009
1010 list_for_each_entry(var_data, &tr->hist_vars, list) {
1011 if (var_data->hist_data == hist_data) {
1012 found = var_data;
1013 break;
1014 }
1015 }
1016
1017 return found;
1018 }
1019
1020 static bool field_has_hist_vars(struct hist_field *hist_field,
1021 unsigned int level)
1022 {
1023 int i;
1024
1025 if (level > 3)
1026 return false;
1027
1028 if (!hist_field)
1029 return false;
1030
1031 if (hist_field->flags & HIST_FIELD_FL_VAR ||
1032 hist_field->flags & HIST_FIELD_FL_VAR_REF)
1033 return true;
1034
1035 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1036 struct hist_field *operand;
1037
1038 operand = hist_field->operands[i];
1039 if (field_has_hist_vars(operand, level + 1))
1040 return true;
1041 }
1042
1043 return false;
1044 }
1045
1046 static bool has_hist_vars(struct hist_trigger_data *hist_data)
1047 {
1048 struct hist_field *hist_field;
1049 int i;
1050
1051 for_each_hist_field(i, hist_data) {
1052 hist_field = hist_data->fields[i];
1053 if (field_has_hist_vars(hist_field, 0))
1054 return true;
1055 }
1056
1057 return false;
1058 }
1059
1060 static int save_hist_vars(struct hist_trigger_data *hist_data)
1061 {
1062 struct trace_array *tr = hist_data->event_file->tr;
1063 struct hist_var_data *var_data;
1064
1065 var_data = find_hist_vars(hist_data);
1066 if (var_data)
1067 return 0;
1068
1069 if (tracing_check_open_get_tr(tr))
1070 return -ENODEV;
1071
1072 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
1073 if (!var_data) {
1074 trace_array_put(tr);
1075 return -ENOMEM;
1076 }
1077
1078 var_data->hist_data = hist_data;
1079 list_add(&var_data->list, &tr->hist_vars);
1080
1081 return 0;
1082 }
1083
1084 static void remove_hist_vars(struct hist_trigger_data *hist_data)
1085 {
1086 struct trace_array *tr = hist_data->event_file->tr;
1087 struct hist_var_data *var_data;
1088
1089 var_data = find_hist_vars(hist_data);
1090 if (!var_data)
1091 return;
1092
1093 if (WARN_ON(check_var_refs(hist_data)))
1094 return;
1095
1096 list_del(&var_data->list);
1097
1098 kfree(var_data);
1099
1100 trace_array_put(tr);
1101 }
1102
1103 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
1104 const char *var_name)
1105 {
1106 struct hist_field *hist_field, *found = NULL;
1107 int i;
1108
1109 for_each_hist_field(i, hist_data) {
1110 hist_field = hist_data->fields[i];
1111 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
1112 strcmp(hist_field->var.name, var_name) == 0) {
1113 found = hist_field;
1114 break;
1115 }
1116 }
1117
1118 return found;
1119 }
1120
1121 static struct hist_field *find_var(struct hist_trigger_data *hist_data,
1122 struct trace_event_file *file,
1123 const char *var_name)
1124 {
1125 struct hist_trigger_data *test_data;
1126 struct event_trigger_data *test;
1127 struct hist_field *hist_field;
1128
1129 lockdep_assert_held(&event_mutex);
1130
1131 hist_field = find_var_field(hist_data, var_name);
1132 if (hist_field)
1133 return hist_field;
1134
1135 list_for_each_entry(test, &file->triggers, list) {
1136 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1137 test_data = test->private_data;
1138 hist_field = find_var_field(test_data, var_name);
1139 if (hist_field)
1140 return hist_field;
1141 }
1142 }
1143
1144 return NULL;
1145 }
1146
1147 static struct trace_event_file *find_var_file(struct trace_array *tr,
1148 char *system,
1149 char *event_name,
1150 char *var_name)
1151 {
1152 struct hist_trigger_data *var_hist_data;
1153 struct hist_var_data *var_data;
1154 struct trace_event_file *file, *found = NULL;
1155
1156 if (system)
1157 return find_event_file(tr, system, event_name);
1158
1159 list_for_each_entry(var_data, &tr->hist_vars, list) {
1160 var_hist_data = var_data->hist_data;
1161 file = var_hist_data->event_file;
1162 if (file == found)
1163 continue;
1164
1165 if (find_var_field(var_hist_data, var_name)) {
1166 if (found) {
1167 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name));
1168 return NULL;
1169 }
1170
1171 found = file;
1172 }
1173 }
1174
1175 return found;
1176 }
1177
1178 static struct hist_field *find_file_var(struct trace_event_file *file,
1179 const char *var_name)
1180 {
1181 struct hist_trigger_data *test_data;
1182 struct event_trigger_data *test;
1183 struct hist_field *hist_field;
1184
1185 lockdep_assert_held(&event_mutex);
1186
1187 list_for_each_entry(test, &file->triggers, list) {
1188 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1189 test_data = test->private_data;
1190 hist_field = find_var_field(test_data, var_name);
1191 if (hist_field)
1192 return hist_field;
1193 }
1194 }
1195
1196 return NULL;
1197 }
1198
1199 static struct hist_field *
1200 find_match_var(struct hist_trigger_data *hist_data, char *var_name)
1201 {
1202 struct trace_array *tr = hist_data->event_file->tr;
1203 struct hist_field *hist_field, *found = NULL;
1204 struct trace_event_file *file;
1205 unsigned int i;
1206
1207 for (i = 0; i < hist_data->n_actions; i++) {
1208 struct action_data *data = hist_data->actions[i];
1209
1210 if (data->handler == HANDLER_ONMATCH) {
1211 char *system = data->match_data.event_system;
1212 char *event_name = data->match_data.event;
1213
1214 file = find_var_file(tr, system, event_name, var_name);
1215 if (!file)
1216 continue;
1217 hist_field = find_file_var(file, var_name);
1218 if (hist_field) {
1219 if (found) {
1220 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE,
1221 errpos(var_name));
1222 return ERR_PTR(-EINVAL);
1223 }
1224
1225 found = hist_field;
1226 }
1227 }
1228 }
1229 return found;
1230 }
1231
1232 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
1233 char *system,
1234 char *event_name,
1235 char *var_name)
1236 {
1237 struct trace_array *tr = hist_data->event_file->tr;
1238 struct hist_field *hist_field = NULL;
1239 struct trace_event_file *file;
1240
1241 if (!system || !event_name) {
1242 hist_field = find_match_var(hist_data, var_name);
1243 if (IS_ERR(hist_field))
1244 return NULL;
1245 if (hist_field)
1246 return hist_field;
1247 }
1248
1249 file = find_var_file(tr, system, event_name, var_name);
1250 if (!file)
1251 return NULL;
1252
1253 hist_field = find_file_var(file, var_name);
1254
1255 return hist_field;
1256 }
1257
1258 static u64 hist_field_var_ref(struct hist_field *hist_field,
1259 struct tracing_map_elt *elt,
1260 struct trace_buffer *buffer,
1261 struct ring_buffer_event *rbe,
1262 void *event)
1263 {
1264 struct hist_elt_data *elt_data;
1265 u64 var_val = 0;
1266
1267 if (WARN_ON_ONCE(!elt))
1268 return var_val;
1269
1270 elt_data = elt->private_data;
1271 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1272
1273 return var_val;
1274 }
1275
1276 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1277 u64 *var_ref_vals, bool self)
1278 {
1279 struct hist_trigger_data *var_data;
1280 struct tracing_map_elt *var_elt;
1281 struct hist_field *hist_field;
1282 unsigned int i, var_idx;
1283 bool resolved = true;
1284 u64 var_val = 0;
1285
1286 for (i = 0; i < hist_data->n_var_refs; i++) {
1287 hist_field = hist_data->var_refs[i];
1288 var_idx = hist_field->var.idx;
1289 var_data = hist_field->var.hist_data;
1290
1291 if (var_data == NULL) {
1292 resolved = false;
1293 break;
1294 }
1295
1296 if ((self && var_data != hist_data) ||
1297 (!self && var_data == hist_data))
1298 continue;
1299
1300 var_elt = tracing_map_lookup(var_data->map, key);
1301 if (!var_elt) {
1302 resolved = false;
1303 break;
1304 }
1305
1306 if (!tracing_map_var_set(var_elt, var_idx)) {
1307 resolved = false;
1308 break;
1309 }
1310
1311 if (self || !hist_field->read_once)
1312 var_val = tracing_map_read_var(var_elt, var_idx);
1313 else
1314 var_val = tracing_map_read_var_once(var_elt, var_idx);
1315
1316 var_ref_vals[i] = var_val;
1317 }
1318
1319 return resolved;
1320 }
1321
1322 static const char *hist_field_name(struct hist_field *field,
1323 unsigned int level)
1324 {
1325 const char *field_name = "";
1326
1327 if (WARN_ON_ONCE(!field))
1328 return field_name;
1329
1330 if (level > 1)
1331 return field_name;
1332
1333 if (field->field)
1334 field_name = field->field->name;
1335 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1336 field->flags & HIST_FIELD_FL_ALIAS ||
1337 field->flags & HIST_FIELD_FL_BUCKET)
1338 field_name = hist_field_name(field->operands[0], ++level);
1339 else if (field->flags & HIST_FIELD_FL_CPU)
1340 field_name = "common_cpu";
1341 else if (field->flags & HIST_FIELD_FL_EXPR ||
1342 field->flags & HIST_FIELD_FL_VAR_REF) {
1343 if (field->system) {
1344 static char full_name[MAX_FILTER_STR_VAL];
1345
1346 strcat(full_name, field->system);
1347 strcat(full_name, ".");
1348 strcat(full_name, field->event_name);
1349 strcat(full_name, ".");
1350 strcat(full_name, field->name);
1351 field_name = full_name;
1352 } else
1353 field_name = field->name;
1354 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1355 field_name = "common_timestamp";
1356 else if (field->flags & HIST_FIELD_FL_STACKTRACE) {
1357 field_name = "common_stacktrace";
1358 } else if (field->flags & HIST_FIELD_FL_HITCOUNT)
1359 field_name = "hitcount";
1360
1361 if (field_name == NULL)
1362 field_name = "";
1363
1364 return field_name;
1365 }
1366
1367 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed)
1368 {
1369 switch (field_size) {
1370 case 8:
1371 if (field_is_signed)
1372 return HIST_FIELD_FN_S64;
1373 else
1374 return HIST_FIELD_FN_U64;
1375 case 4:
1376 if (field_is_signed)
1377 return HIST_FIELD_FN_S32;
1378 else
1379 return HIST_FIELD_FN_U32;
1380 case 2:
1381 if (field_is_signed)
1382 return HIST_FIELD_FN_S16;
1383 else
1384 return HIST_FIELD_FN_U16;
1385 case 1:
1386 if (field_is_signed)
1387 return HIST_FIELD_FN_S8;
1388 else
1389 return HIST_FIELD_FN_U8;
1390 }
1391
1392 return HIST_FIELD_FN_NOP;
1393 }
1394
1395 static int parse_map_size(char *str)
1396 {
1397 unsigned long size, map_bits;
1398 int ret;
1399
1400 ret = kstrtoul(str, 0, &size);
1401 if (ret)
1402 goto out;
1403
1404 map_bits = ilog2(roundup_pow_of_two(size));
1405 if (map_bits < TRACING_MAP_BITS_MIN ||
1406 map_bits > TRACING_MAP_BITS_MAX)
1407 ret = -EINVAL;
1408 else
1409 ret = map_bits;
1410 out:
1411 return ret;
1412 }
1413
1414 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1415 {
1416 unsigned int i;
1417
1418 if (!attrs)
1419 return;
1420
1421 for (i = 0; i < attrs->n_assignments; i++)
1422 kfree(attrs->assignment_str[i]);
1423
1424 for (i = 0; i < attrs->n_actions; i++)
1425 kfree(attrs->action_str[i]);
1426
1427 kfree(attrs->name);
1428 kfree(attrs->sort_key_str);
1429 kfree(attrs->keys_str);
1430 kfree(attrs->vals_str);
1431 kfree(attrs->clock);
1432 kfree(attrs);
1433 }
1434
1435 static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1436 {
1437 int ret = -EINVAL;
1438
1439 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1440 return ret;
1441
1442 if ((str_has_prefix(str, "onmatch(")) ||
1443 (str_has_prefix(str, "onmax(")) ||
1444 (str_has_prefix(str, "onchange("))) {
1445 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
1446 if (!attrs->action_str[attrs->n_actions]) {
1447 ret = -ENOMEM;
1448 return ret;
1449 }
1450 attrs->n_actions++;
1451 ret = 0;
1452 }
1453 return ret;
1454 }
1455
1456 static int parse_assignment(struct trace_array *tr,
1457 char *str, struct hist_trigger_attrs *attrs)
1458 {
1459 int len, ret = 0;
1460
1461 if ((len = str_has_prefix(str, "key=")) ||
1462 (len = str_has_prefix(str, "keys="))) {
1463 attrs->keys_str = kstrdup(str + len, GFP_KERNEL);
1464 if (!attrs->keys_str) {
1465 ret = -ENOMEM;
1466 goto out;
1467 }
1468 } else if ((len = str_has_prefix(str, "val=")) ||
1469 (len = str_has_prefix(str, "vals=")) ||
1470 (len = str_has_prefix(str, "values="))) {
1471 attrs->vals_str = kstrdup(str + len, GFP_KERNEL);
1472 if (!attrs->vals_str) {
1473 ret = -ENOMEM;
1474 goto out;
1475 }
1476 } else if ((len = str_has_prefix(str, "sort="))) {
1477 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL);
1478 if (!attrs->sort_key_str) {
1479 ret = -ENOMEM;
1480 goto out;
1481 }
1482 } else if (str_has_prefix(str, "name=")) {
1483 attrs->name = kstrdup(str, GFP_KERNEL);
1484 if (!attrs->name) {
1485 ret = -ENOMEM;
1486 goto out;
1487 }
1488 } else if ((len = str_has_prefix(str, "clock="))) {
1489 str += len;
1490
1491 str = strstrip(str);
1492 attrs->clock = kstrdup(str, GFP_KERNEL);
1493 if (!attrs->clock) {
1494 ret = -ENOMEM;
1495 goto out;
1496 }
1497 } else if ((len = str_has_prefix(str, "size="))) {
1498 int map_bits = parse_map_size(str + len);
1499
1500 if (map_bits < 0) {
1501 ret = map_bits;
1502 goto out;
1503 }
1504 attrs->map_bits = map_bits;
1505 } else {
1506 char *assignment;
1507
1508 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1509 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str));
1510 ret = -EINVAL;
1511 goto out;
1512 }
1513
1514 assignment = kstrdup(str, GFP_KERNEL);
1515 if (!assignment) {
1516 ret = -ENOMEM;
1517 goto out;
1518 }
1519
1520 attrs->assignment_str[attrs->n_assignments++] = assignment;
1521 }
1522 out:
1523 return ret;
1524 }
1525
1526 static struct hist_trigger_attrs *
1527 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
1528 {
1529 struct hist_trigger_attrs *attrs;
1530 int ret = 0;
1531
1532 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
1533 if (!attrs)
1534 return ERR_PTR(-ENOMEM);
1535
1536 while (trigger_str) {
1537 char *str = strsep(&trigger_str, ":");
1538 char *rhs;
1539
1540 rhs = strchr(str, '=');
1541 if (rhs) {
1542 if (!strlen(++rhs)) {
1543 ret = -EINVAL;
1544 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str));
1545 goto free;
1546 }
1547 ret = parse_assignment(tr, str, attrs);
1548 if (ret)
1549 goto free;
1550 } else if (strcmp(str, "nohitcount") == 0 ||
1551 strcmp(str, "NOHC") == 0)
1552 attrs->no_hitcount = true;
1553 else if (strcmp(str, "pause") == 0)
1554 attrs->pause = true;
1555 else if ((strcmp(str, "cont") == 0) ||
1556 (strcmp(str, "continue") == 0))
1557 attrs->cont = true;
1558 else if (strcmp(str, "clear") == 0)
1559 attrs->clear = true;
1560 else {
1561 ret = parse_action(str, attrs);
1562 if (ret)
1563 goto free;
1564 }
1565 }
1566
1567 if (!attrs->keys_str) {
1568 ret = -EINVAL;
1569 goto free;
1570 }
1571
1572 if (!attrs->clock) {
1573 attrs->clock = kstrdup("global", GFP_KERNEL);
1574 if (!attrs->clock) {
1575 ret = -ENOMEM;
1576 goto free;
1577 }
1578 }
1579
1580 return attrs;
1581 free:
1582 destroy_hist_trigger_attrs(attrs);
1583
1584 return ERR_PTR(ret);
1585 }
1586
1587 static inline void save_comm(char *comm, struct task_struct *task)
1588 {
1589 if (!task->pid) {
1590 strcpy(comm, "<idle>");
1591 return;
1592 }
1593
1594 if (WARN_ON_ONCE(task->pid < 0)) {
1595 strcpy(comm, "<XXX>");
1596 return;
1597 }
1598
1599 strscpy(comm, task->comm, TASK_COMM_LEN);
1600 }
1601
1602 static void hist_elt_data_free(struct hist_elt_data *elt_data)
1603 {
1604 unsigned int i;
1605
1606 for (i = 0; i < elt_data->n_field_var_str; i++)
1607 kfree(elt_data->field_var_str[i]);
1608
1609 kfree(elt_data->field_var_str);
1610
1611 kfree(elt_data->comm);
1612 kfree(elt_data);
1613 }
1614
1615 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1616 {
1617 struct hist_elt_data *elt_data = elt->private_data;
1618
1619 hist_elt_data_free(elt_data);
1620 }
1621
1622 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1623 {
1624 struct hist_trigger_data *hist_data = elt->map->private_data;
1625 unsigned int size = TASK_COMM_LEN;
1626 struct hist_elt_data *elt_data;
1627 struct hist_field *hist_field;
1628 unsigned int i, n_str;
1629
1630 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
1631 if (!elt_data)
1632 return -ENOMEM;
1633
1634 for_each_hist_field(i, hist_data) {
1635 hist_field = hist_data->fields[i];
1636
1637 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) {
1638 elt_data->comm = kzalloc(size, GFP_KERNEL);
1639 if (!elt_data->comm) {
1640 kfree(elt_data);
1641 return -ENOMEM;
1642 }
1643 break;
1644 }
1645 }
1646
1647 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str +
1648 hist_data->n_var_str;
1649 if (n_str > SYNTH_FIELDS_MAX) {
1650 hist_elt_data_free(elt_data);
1651 return -EINVAL;
1652 }
1653
1654 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1));
1655
1656 size = STR_VAR_LEN_MAX;
1657
1658 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL);
1659 if (!elt_data->field_var_str) {
1660 hist_elt_data_free(elt_data);
1661 return -EINVAL;
1662 }
1663 elt_data->n_field_var_str = n_str;
1664
1665 for (i = 0; i < n_str; i++) {
1666 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
1667 if (!elt_data->field_var_str[i]) {
1668 hist_elt_data_free(elt_data);
1669 return -ENOMEM;
1670 }
1671 }
1672
1673 elt->private_data = elt_data;
1674
1675 return 0;
1676 }
1677
1678 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
1679 {
1680 struct hist_elt_data *elt_data = elt->private_data;
1681
1682 if (elt_data->comm)
1683 save_comm(elt_data->comm, current);
1684 }
1685
1686 static const struct tracing_map_ops hist_trigger_elt_data_ops = {
1687 .elt_alloc = hist_trigger_elt_data_alloc,
1688 .elt_free = hist_trigger_elt_data_free,
1689 .elt_init = hist_trigger_elt_data_init,
1690 };
1691
1692 static const char *get_hist_field_flags(struct hist_field *hist_field)
1693 {
1694 const char *flags_str = NULL;
1695
1696 if (hist_field->flags & HIST_FIELD_FL_HEX)
1697 flags_str = "hex";
1698 else if (hist_field->flags & HIST_FIELD_FL_SYM)
1699 flags_str = "sym";
1700 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
1701 flags_str = "sym-offset";
1702 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
1703 flags_str = "execname";
1704 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
1705 flags_str = "syscall";
1706 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
1707 flags_str = "log2";
1708 else if (hist_field->flags & HIST_FIELD_FL_BUCKET)
1709 flags_str = "buckets";
1710 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1711 flags_str = "usecs";
1712 else if (hist_field->flags & HIST_FIELD_FL_PERCENT)
1713 flags_str = "percent";
1714 else if (hist_field->flags & HIST_FIELD_FL_GRAPH)
1715 flags_str = "graph";
1716 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
1717 flags_str = "stacktrace";
1718
1719 return flags_str;
1720 }
1721
1722 static void expr_field_str(struct hist_field *field, char *expr)
1723 {
1724 if (field->flags & HIST_FIELD_FL_VAR_REF)
1725 strcat(expr, "$");
1726 else if (field->flags & HIST_FIELD_FL_CONST) {
1727 char str[HIST_CONST_DIGITS_MAX];
1728
1729 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant);
1730 strcat(expr, str);
1731 }
1732
1733 strcat(expr, hist_field_name(field, 0));
1734
1735 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
1736 const char *flags_str = get_hist_field_flags(field);
1737
1738 if (flags_str) {
1739 strcat(expr, ".");
1740 strcat(expr, flags_str);
1741 }
1742 }
1743 }
1744
1745 static char *expr_str(struct hist_field *field, unsigned int level)
1746 {
1747 char *expr;
1748
1749 if (level > 1)
1750 return NULL;
1751
1752 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
1753 if (!expr)
1754 return NULL;
1755
1756 if (!field->operands[0]) {
1757 expr_field_str(field, expr);
1758 return expr;
1759 }
1760
1761 if (field->operator == FIELD_OP_UNARY_MINUS) {
1762 char *subexpr;
1763
1764 strcat(expr, "-(");
1765 subexpr = expr_str(field->operands[0], ++level);
1766 if (!subexpr) {
1767 kfree(expr);
1768 return NULL;
1769 }
1770 strcat(expr, subexpr);
1771 strcat(expr, ")");
1772
1773 kfree(subexpr);
1774
1775 return expr;
1776 }
1777
1778 expr_field_str(field->operands[0], expr);
1779
1780 switch (field->operator) {
1781 case FIELD_OP_MINUS:
1782 strcat(expr, "-");
1783 break;
1784 case FIELD_OP_PLUS:
1785 strcat(expr, "+");
1786 break;
1787 case FIELD_OP_DIV:
1788 strcat(expr, "/");
1789 break;
1790 case FIELD_OP_MULT:
1791 strcat(expr, "*");
1792 break;
1793 default:
1794 kfree(expr);
1795 return NULL;
1796 }
1797
1798 expr_field_str(field->operands[1], expr);
1799
1800 return expr;
1801 }
1802
1803 /*
1804 * If field_op != FIELD_OP_NONE, *sep points to the root operator
1805 * of the expression tree to be evaluated.
1806 */
1807 static int contains_operator(char *str, char **sep)
1808 {
1809 enum field_op_id field_op = FIELD_OP_NONE;
1810 char *minus_op, *plus_op, *div_op, *mult_op;
1811
1812
1813 /*
1814 * Report the last occurrence of the operators first, so that the
1815 * expression is evaluated left to right. This is important since
1816 * subtraction and division are not associative.
1817 *
1818 * e.g
1819 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2
1820 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2
1821 */
1822
1823 /*
1824 * First, find lower precedence addition and subtraction
1825 * since the expression will be evaluated recursively.
1826 */
1827 minus_op = strrchr(str, '-');
1828 if (minus_op) {
1829 /*
1830 * Unary minus is not supported in sub-expressions. If
1831 * present, it is always the next root operator.
1832 */
1833 if (minus_op == str) {
1834 field_op = FIELD_OP_UNARY_MINUS;
1835 goto out;
1836 }
1837
1838 field_op = FIELD_OP_MINUS;
1839 }
1840
1841 plus_op = strrchr(str, '+');
1842 if (plus_op || minus_op) {
1843 /*
1844 * For operators of the same precedence use to rightmost as the
1845 * root, so that the expression is evaluated left to right.
1846 */
1847 if (plus_op > minus_op)
1848 field_op = FIELD_OP_PLUS;
1849 goto out;
1850 }
1851
1852 /*
1853 * Multiplication and division have higher precedence than addition and
1854 * subtraction.
1855 */
1856 div_op = strrchr(str, '/');
1857 if (div_op)
1858 field_op = FIELD_OP_DIV;
1859
1860 mult_op = strrchr(str, '*');
1861 /*
1862 * For operators of the same precedence use to rightmost as the
1863 * root, so that the expression is evaluated left to right.
1864 */
1865 if (mult_op > div_op)
1866 field_op = FIELD_OP_MULT;
1867
1868 out:
1869 if (sep) {
1870 switch (field_op) {
1871 case FIELD_OP_UNARY_MINUS:
1872 case FIELD_OP_MINUS:
1873 *sep = minus_op;
1874 break;
1875 case FIELD_OP_PLUS:
1876 *sep = plus_op;
1877 break;
1878 case FIELD_OP_DIV:
1879 *sep = div_op;
1880 break;
1881 case FIELD_OP_MULT:
1882 *sep = mult_op;
1883 break;
1884 case FIELD_OP_NONE:
1885 default:
1886 *sep = NULL;
1887 break;
1888 }
1889 }
1890
1891 return field_op;
1892 }
1893
1894 static void get_hist_field(struct hist_field *hist_field)
1895 {
1896 hist_field->ref++;
1897 }
1898
1899 static void __destroy_hist_field(struct hist_field *hist_field)
1900 {
1901 if (--hist_field->ref > 1)
1902 return;
1903
1904 kfree(hist_field->var.name);
1905 kfree(hist_field->name);
1906
1907 /* Can likely be a const */
1908 kfree_const(hist_field->type);
1909
1910 kfree(hist_field->system);
1911 kfree(hist_field->event_name);
1912
1913 kfree(hist_field);
1914 }
1915
1916 static void destroy_hist_field(struct hist_field *hist_field,
1917 unsigned int level)
1918 {
1919 unsigned int i;
1920
1921 if (level > 3)
1922 return;
1923
1924 if (!hist_field)
1925 return;
1926
1927 if (hist_field->flags & HIST_FIELD_FL_VAR_REF)
1928 return; /* var refs will be destroyed separately */
1929
1930 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
1931 destroy_hist_field(hist_field->operands[i], level + 1);
1932
1933 __destroy_hist_field(hist_field);
1934 }
1935
1936 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
1937 struct ftrace_event_field *field,
1938 unsigned long flags,
1939 char *var_name)
1940 {
1941 struct hist_field *hist_field;
1942
1943 if (field && is_function_field(field))
1944 return NULL;
1945
1946 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
1947 if (!hist_field)
1948 return NULL;
1949
1950 hist_field->ref = 1;
1951
1952 hist_field->hist_data = hist_data;
1953
1954 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
1955 goto out; /* caller will populate */
1956
1957 if (flags & HIST_FIELD_FL_VAR_REF) {
1958 hist_field->fn_num = HIST_FIELD_FN_VAR_REF;
1959 goto out;
1960 }
1961
1962 if (flags & HIST_FIELD_FL_HITCOUNT) {
1963 hist_field->fn_num = HIST_FIELD_FN_COUNTER;
1964 hist_field->size = sizeof(u64);
1965 hist_field->type = "u64";
1966 goto out;
1967 }
1968
1969 if (flags & HIST_FIELD_FL_CONST) {
1970 hist_field->fn_num = HIST_FIELD_FN_CONST;
1971 hist_field->size = sizeof(u64);
1972 hist_field->type = kstrdup("u64", GFP_KERNEL);
1973 if (!hist_field->type)
1974 goto free;
1975 goto out;
1976 }
1977
1978 if (flags & HIST_FIELD_FL_STACKTRACE) {
1979 if (field)
1980 hist_field->fn_num = HIST_FIELD_FN_STACK;
1981 else
1982 hist_field->fn_num = HIST_FIELD_FN_NOP;
1983 hist_field->size = HIST_STACKTRACE_SIZE;
1984 hist_field->type = kstrdup_const("unsigned long[]", GFP_KERNEL);
1985 if (!hist_field->type)
1986 goto free;
1987 goto out;
1988 }
1989
1990 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) {
1991 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET);
1992 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 :
1993 HIST_FIELD_FN_BUCKET;
1994 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
1995 if (!hist_field->operands[0])
1996 goto free;
1997 hist_field->size = hist_field->operands[0]->size;
1998 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL);
1999 if (!hist_field->type)
2000 goto free;
2001 goto out;
2002 }
2003
2004 if (flags & HIST_FIELD_FL_TIMESTAMP) {
2005 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP;
2006 hist_field->size = sizeof(u64);
2007 hist_field->type = "u64";
2008 goto out;
2009 }
2010
2011 if (flags & HIST_FIELD_FL_CPU) {
2012 hist_field->fn_num = HIST_FIELD_FN_CPU;
2013 hist_field->size = sizeof(int);
2014 hist_field->type = "unsigned int";
2015 goto out;
2016 }
2017
2018 if (WARN_ON_ONCE(!field))
2019 goto out;
2020
2021 /* Pointers to strings are just pointers and dangerous to dereference */
2022 if (is_string_field(field) &&
2023 (field->filter_type != FILTER_PTR_STRING)) {
2024 flags |= HIST_FIELD_FL_STRING;
2025
2026 hist_field->size = MAX_FILTER_STR_VAL;
2027 hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
2028 if (!hist_field->type)
2029 goto free;
2030
2031 if (field->filter_type == FILTER_STATIC_STRING) {
2032 hist_field->fn_num = HIST_FIELD_FN_STRING;
2033 hist_field->size = field->size;
2034 } else if (field->filter_type == FILTER_DYN_STRING) {
2035 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING;
2036 } else if (field->filter_type == FILTER_RDYN_STRING)
2037 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING;
2038 else
2039 hist_field->fn_num = HIST_FIELD_FN_PSTRING;
2040 } else {
2041 hist_field->size = field->size;
2042 hist_field->is_signed = field->is_signed;
2043 hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
2044 if (!hist_field->type)
2045 goto free;
2046
2047 hist_field->fn_num = select_value_fn(field->size,
2048 field->is_signed);
2049 if (hist_field->fn_num == HIST_FIELD_FN_NOP) {
2050 destroy_hist_field(hist_field, 0);
2051 return NULL;
2052 }
2053 }
2054 out:
2055 hist_field->field = field;
2056 hist_field->flags = flags;
2057
2058 if (var_name) {
2059 hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
2060 if (!hist_field->var.name)
2061 goto free;
2062 }
2063
2064 return hist_field;
2065 free:
2066 destroy_hist_field(hist_field, 0);
2067 return NULL;
2068 }
2069
2070 static void destroy_hist_fields(struct hist_trigger_data *hist_data)
2071 {
2072 unsigned int i;
2073
2074 for (i = 0; i < HIST_FIELDS_MAX; i++) {
2075 if (hist_data->fields[i]) {
2076 destroy_hist_field(hist_data->fields[i], 0);
2077 hist_data->fields[i] = NULL;
2078 }
2079 }
2080
2081 for (i = 0; i < hist_data->n_var_refs; i++) {
2082 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF));
2083 __destroy_hist_field(hist_data->var_refs[i]);
2084 hist_data->var_refs[i] = NULL;
2085 }
2086 }
2087
2088 static int init_var_ref(struct hist_field *ref_field,
2089 struct hist_field *var_field,
2090 char *system, char *event_name)
2091 {
2092 int err = 0;
2093
2094 ref_field->var.idx = var_field->var.idx;
2095 ref_field->var.hist_data = var_field->hist_data;
2096 ref_field->size = var_field->size;
2097 ref_field->is_signed = var_field->is_signed;
2098 ref_field->flags |= var_field->flags &
2099 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2100
2101 if (system) {
2102 ref_field->system = kstrdup(system, GFP_KERNEL);
2103 if (!ref_field->system)
2104 return -ENOMEM;
2105 }
2106
2107 if (event_name) {
2108 ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
2109 if (!ref_field->event_name) {
2110 err = -ENOMEM;
2111 goto free;
2112 }
2113 }
2114
2115 if (var_field->var.name) {
2116 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
2117 if (!ref_field->name) {
2118 err = -ENOMEM;
2119 goto free;
2120 }
2121 } else if (var_field->name) {
2122 ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
2123 if (!ref_field->name) {
2124 err = -ENOMEM;
2125 goto free;
2126 }
2127 }
2128
2129 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL);
2130 if (!ref_field->type) {
2131 err = -ENOMEM;
2132 goto free;
2133 }
2134 out:
2135 return err;
2136 free:
2137 kfree(ref_field->system);
2138 ref_field->system = NULL;
2139 kfree(ref_field->event_name);
2140 ref_field->event_name = NULL;
2141 kfree(ref_field->name);
2142 ref_field->name = NULL;
2143
2144 goto out;
2145 }
2146
2147 static int find_var_ref_idx(struct hist_trigger_data *hist_data,
2148 struct hist_field *var_field)
2149 {
2150 struct hist_field *ref_field;
2151 int i;
2152
2153 for (i = 0; i < hist_data->n_var_refs; i++) {
2154 ref_field = hist_data->var_refs[i];
2155 if (ref_field->var.idx == var_field->var.idx &&
2156 ref_field->var.hist_data == var_field->hist_data)
2157 return i;
2158 }
2159
2160 return -ENOENT;
2161 }
2162
2163 /**
2164 * create_var_ref - Create a variable reference and attach it to trigger
2165 * @hist_data: The trigger that will be referencing the variable
2166 * @var_field: The VAR field to create a reference to
2167 * @system: The optional system string
2168 * @event_name: The optional event_name string
2169 *
2170 * Given a variable hist_field, create a VAR_REF hist_field that
2171 * represents a reference to it.
2172 *
2173 * This function also adds the reference to the trigger that
2174 * now references the variable.
2175 *
2176 * Return: The VAR_REF field if successful, NULL if not
2177 */
2178 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
2179 struct hist_field *var_field,
2180 char *system, char *event_name)
2181 {
2182 unsigned long flags = HIST_FIELD_FL_VAR_REF;
2183 struct hist_field *ref_field;
2184 int i;
2185
2186 /* Check if the variable already exists */
2187 for (i = 0; i < hist_data->n_var_refs; i++) {
2188 ref_field = hist_data->var_refs[i];
2189 if (ref_field->var.idx == var_field->var.idx &&
2190 ref_field->var.hist_data == var_field->hist_data) {
2191 get_hist_field(ref_field);
2192 return ref_field;
2193 }
2194 }
2195 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */
2196 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX)
2197 return NULL;
2198 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
2199 if (ref_field) {
2200 if (init_var_ref(ref_field, var_field, system, event_name)) {
2201 destroy_hist_field(ref_field, 0);
2202 return NULL;
2203 }
2204
2205 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
2206 ref_field->var_ref_idx = hist_data->n_var_refs++;
2207 }
2208
2209 return ref_field;
2210 }
2211
2212 static bool is_var_ref(char *var_name)
2213 {
2214 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
2215 return false;
2216
2217 return true;
2218 }
2219
2220 static char *field_name_from_var(struct hist_trigger_data *hist_data,
2221 char *var_name)
2222 {
2223 char *name, *field;
2224 unsigned int i;
2225
2226 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
2227 name = hist_data->attrs->var_defs.name[i];
2228
2229 if (strcmp(var_name, name) == 0) {
2230 field = hist_data->attrs->var_defs.expr[i];
2231 if (contains_operator(field, NULL) || is_var_ref(field))
2232 continue;
2233 return field;
2234 }
2235 }
2236
2237 return NULL;
2238 }
2239
2240 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
2241 char *system, char *event_name,
2242 char *var_name)
2243 {
2244 struct trace_event_call *call;
2245
2246 if (system && event_name) {
2247 call = hist_data->event_file->event_call;
2248
2249 if (strcmp(system, call->class->system) != 0)
2250 return NULL;
2251
2252 if (strcmp(event_name, trace_event_name(call)) != 0)
2253 return NULL;
2254 }
2255
2256 if (!!system != !!event_name)
2257 return NULL;
2258
2259 if (!is_var_ref(var_name))
2260 return NULL;
2261
2262 var_name++;
2263
2264 return field_name_from_var(hist_data, var_name);
2265 }
2266
2267 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
2268 char *system, char *event_name,
2269 char *var_name)
2270 {
2271 struct hist_field *var_field = NULL, *ref_field = NULL;
2272 struct trace_array *tr = hist_data->event_file->tr;
2273
2274 if (!is_var_ref(var_name))
2275 return NULL;
2276
2277 var_name++;
2278
2279 var_field = find_event_var(hist_data, system, event_name, var_name);
2280 if (var_field)
2281 ref_field = create_var_ref(hist_data, var_field,
2282 system, event_name);
2283
2284 if (!ref_field)
2285 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name));
2286
2287 return ref_field;
2288 }
2289
2290 static struct ftrace_event_field *
2291 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
2292 char *field_str, unsigned long *flags, unsigned long *buckets)
2293 {
2294 struct ftrace_event_field *field = NULL;
2295 char *field_name, *modifier, *str;
2296 struct trace_array *tr = file->tr;
2297
2298 modifier = str = kstrdup(field_str, GFP_KERNEL);
2299 if (!modifier)
2300 return ERR_PTR(-ENOMEM);
2301
2302 field_name = strsep(&modifier, ".");
2303 if (modifier) {
2304 if (strcmp(modifier, "hex") == 0)
2305 *flags |= HIST_FIELD_FL_HEX;
2306 else if (strcmp(modifier, "sym") == 0)
2307 *flags |= HIST_FIELD_FL_SYM;
2308 /*
2309 * 'sym-offset' occurrences in the trigger string are modified
2310 * to 'symXoffset' to simplify arithmetic expression parsing.
2311 */
2312 else if (strcmp(modifier, "symXoffset") == 0)
2313 *flags |= HIST_FIELD_FL_SYM_OFFSET;
2314 else if ((strcmp(modifier, "execname") == 0) &&
2315 (strcmp(field_name, "common_pid") == 0))
2316 *flags |= HIST_FIELD_FL_EXECNAME;
2317 else if (strcmp(modifier, "syscall") == 0)
2318 *flags |= HIST_FIELD_FL_SYSCALL;
2319 else if (strcmp(modifier, "stacktrace") == 0)
2320 *flags |= HIST_FIELD_FL_STACKTRACE;
2321 else if (strcmp(modifier, "log2") == 0)
2322 *flags |= HIST_FIELD_FL_LOG2;
2323 else if (strcmp(modifier, "usecs") == 0)
2324 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
2325 else if (strncmp(modifier, "bucket", 6) == 0) {
2326 int ret;
2327
2328 modifier += 6;
2329
2330 if (*modifier == 's')
2331 modifier++;
2332 if (*modifier != '=')
2333 goto error;
2334 modifier++;
2335 ret = kstrtoul(modifier, 0, buckets);
2336 if (ret || !(*buckets))
2337 goto error;
2338 *flags |= HIST_FIELD_FL_BUCKET;
2339 } else if (strncmp(modifier, "percent", 7) == 0) {
2340 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY))
2341 goto error;
2342 *flags |= HIST_FIELD_FL_PERCENT;
2343 } else if (strncmp(modifier, "graph", 5) == 0) {
2344 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY))
2345 goto error;
2346 *flags |= HIST_FIELD_FL_GRAPH;
2347 } else {
2348 error:
2349 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
2350 field = ERR_PTR(-EINVAL);
2351 goto out;
2352 }
2353 }
2354
2355 if (strcmp(field_name, "common_timestamp") == 0) {
2356 *flags |= HIST_FIELD_FL_TIMESTAMP;
2357 hist_data->enable_timestamps = true;
2358 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2359 hist_data->attrs->ts_in_usecs = true;
2360 } else if (strcmp(field_name, "common_stacktrace") == 0) {
2361 *flags |= HIST_FIELD_FL_STACKTRACE;
2362 } else if (strcmp(field_name, "common_cpu") == 0)
2363 *flags |= HIST_FIELD_FL_CPU;
2364 else if (strcmp(field_name, "hitcount") == 0)
2365 *flags |= HIST_FIELD_FL_HITCOUNT;
2366 else {
2367 field = trace_find_event_field(file->event_call, field_name);
2368 if (!field || !field->size) {
2369 /*
2370 * For backward compatibility, if field_name
2371 * was "cpu" or "stacktrace", then we treat this
2372 * the same as common_cpu and common_stacktrace
2373 * respectively. This also works for "CPU", and
2374 * "STACKTRACE".
2375 */
2376 if (field && field->filter_type == FILTER_CPU) {
2377 *flags |= HIST_FIELD_FL_CPU;
2378 } else if (field && field->filter_type == FILTER_STACKTRACE) {
2379 *flags |= HIST_FIELD_FL_STACKTRACE;
2380 } else {
2381 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND,
2382 errpos(field_name));
2383 field = ERR_PTR(-EINVAL);
2384 goto out;
2385 }
2386 }
2387 }
2388 out:
2389 kfree(str);
2390
2391 return field;
2392 }
2393
2394 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2395 struct hist_field *var_ref,
2396 char *var_name)
2397 {
2398 struct hist_field *alias = NULL;
2399 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2400
2401 alias = create_hist_field(hist_data, NULL, flags, var_name);
2402 if (!alias)
2403 return NULL;
2404
2405 alias->fn_num = var_ref->fn_num;
2406 alias->operands[0] = var_ref;
2407
2408 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2409 destroy_hist_field(alias, 0);
2410 return NULL;
2411 }
2412
2413 alias->var_ref_idx = var_ref->var_ref_idx;
2414
2415 return alias;
2416 }
2417
2418 static struct hist_field *parse_const(struct hist_trigger_data *hist_data,
2419 char *str, char *var_name,
2420 unsigned long *flags)
2421 {
2422 struct trace_array *tr = hist_data->event_file->tr;
2423 struct hist_field *field = NULL;
2424 u64 constant;
2425
2426 if (kstrtoull(str, 0, &constant)) {
2427 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str));
2428 return NULL;
2429 }
2430
2431 *flags |= HIST_FIELD_FL_CONST;
2432 field = create_hist_field(hist_data, NULL, *flags, var_name);
2433 if (!field)
2434 return NULL;
2435
2436 field->constant = constant;
2437
2438 return field;
2439 }
2440
2441 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2442 struct trace_event_file *file, char *str,
2443 unsigned long *flags, char *var_name)
2444 {
2445 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2446 struct ftrace_event_field *field = NULL;
2447 struct hist_field *hist_field = NULL;
2448 unsigned long buckets = 0;
2449 int ret = 0;
2450
2451 if (isdigit(str[0])) {
2452 hist_field = parse_const(hist_data, str, var_name, flags);
2453 if (!hist_field) {
2454 ret = -EINVAL;
2455 goto out;
2456 }
2457 return hist_field;
2458 }
2459
2460 s = strchr(str, '.');
2461 if (s) {
2462 s = strchr(++s, '.');
2463 if (s) {
2464 ref_system = strsep(&str, ".");
2465 if (!str) {
2466 ret = -EINVAL;
2467 goto out;
2468 }
2469 ref_event = strsep(&str, ".");
2470 if (!str) {
2471 ret = -EINVAL;
2472 goto out;
2473 }
2474 ref_var = str;
2475 }
2476 }
2477
2478 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2479 if (!s) {
2480 hist_field = parse_var_ref(hist_data, ref_system,
2481 ref_event, ref_var);
2482 if (hist_field) {
2483 if (var_name) {
2484 hist_field = create_alias(hist_data, hist_field, var_name);
2485 if (!hist_field) {
2486 ret = -ENOMEM;
2487 goto out;
2488 }
2489 }
2490 return hist_field;
2491 }
2492 } else
2493 str = s;
2494
2495 field = parse_field(hist_data, file, str, flags, &buckets);
2496 if (IS_ERR(field)) {
2497 ret = PTR_ERR(field);
2498 goto out;
2499 }
2500
2501 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2502 if (!hist_field) {
2503 ret = -ENOMEM;
2504 goto out;
2505 }
2506 hist_field->buckets = buckets;
2507
2508 return hist_field;
2509 out:
2510 return ERR_PTR(ret);
2511 }
2512
2513 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2514 struct trace_event_file *file,
2515 char *str, unsigned long flags,
2516 char *var_name, unsigned int *n_subexprs);
2517
2518 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2519 struct trace_event_file *file,
2520 char *str, unsigned long flags,
2521 char *var_name, unsigned int *n_subexprs)
2522 {
2523 struct hist_field *operand1, *expr = NULL;
2524 unsigned long operand_flags;
2525 int ret = 0;
2526 char *s;
2527
2528 /* Unary minus operator, increment n_subexprs */
2529 ++*n_subexprs;
2530
2531 /* we support only -(xxx) i.e. explicit parens required */
2532
2533 if (*n_subexprs > 3) {
2534 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2535 ret = -EINVAL;
2536 goto free;
2537 }
2538
2539 str++; /* skip leading '-' */
2540
2541 s = strchr(str, '(');
2542 if (s)
2543 str++;
2544 else {
2545 ret = -EINVAL;
2546 goto free;
2547 }
2548
2549 s = strrchr(str, ')');
2550 if (s) {
2551 /* unary minus not supported in sub-expressions */
2552 if (*(s+1) != '\0') {
2553 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR,
2554 errpos(str));
2555 ret = -EINVAL;
2556 goto free;
2557 }
2558 *s = '\0';
2559 }
2560 else {
2561 ret = -EINVAL; /* no closing ')' */
2562 goto free;
2563 }
2564
2565 flags |= HIST_FIELD_FL_EXPR;
2566 expr = create_hist_field(hist_data, NULL, flags, var_name);
2567 if (!expr) {
2568 ret = -ENOMEM;
2569 goto free;
2570 }
2571
2572 operand_flags = 0;
2573 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs);
2574 if (IS_ERR(operand1)) {
2575 ret = PTR_ERR(operand1);
2576 goto free;
2577 }
2578 if (operand1->flags & HIST_FIELD_FL_STRING) {
2579 /* String type can not be the operand of unary operator. */
2580 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2581 destroy_hist_field(operand1, 0);
2582 ret = -EINVAL;
2583 goto free;
2584 }
2585
2586 expr->flags |= operand1->flags &
2587 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2588 expr->fn_num = HIST_FIELD_FN_UMINUS;
2589 expr->operands[0] = operand1;
2590 expr->size = operand1->size;
2591 expr->is_signed = operand1->is_signed;
2592 expr->operator = FIELD_OP_UNARY_MINUS;
2593 expr->name = expr_str(expr, 0);
2594 expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
2595 if (!expr->type) {
2596 ret = -ENOMEM;
2597 goto free;
2598 }
2599
2600 return expr;
2601 free:
2602 destroy_hist_field(expr, 0);
2603 return ERR_PTR(ret);
2604 }
2605
2606 /*
2607 * If the operands are var refs, return pointers the
2608 * variable(s) referenced in var1 and var2, else NULL.
2609 */
2610 static int check_expr_operands(struct trace_array *tr,
2611 struct hist_field *operand1,
2612 struct hist_field *operand2,
2613 struct hist_field **var1,
2614 struct hist_field **var2)
2615 {
2616 unsigned long operand1_flags = operand1->flags;
2617 unsigned long operand2_flags = operand2->flags;
2618
2619 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2620 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2621 struct hist_field *var;
2622
2623 var = find_var_field(operand1->var.hist_data, operand1->name);
2624 if (!var)
2625 return -EINVAL;
2626 operand1_flags = var->flags;
2627 *var1 = var;
2628 }
2629
2630 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2631 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2632 struct hist_field *var;
2633
2634 var = find_var_field(operand2->var.hist_data, operand2->name);
2635 if (!var)
2636 return -EINVAL;
2637 operand2_flags = var->flags;
2638 *var2 = var;
2639 }
2640
2641 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2642 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2643 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0);
2644 return -EINVAL;
2645 }
2646
2647 return 0;
2648 }
2649
2650 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2651 struct trace_event_file *file,
2652 char *str, unsigned long flags,
2653 char *var_name, unsigned int *n_subexprs)
2654 {
2655 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2656 struct hist_field *var1 = NULL, *var2 = NULL;
2657 unsigned long operand_flags, operand2_flags;
2658 int field_op, ret = -EINVAL;
2659 char *sep, *operand1_str;
2660 enum hist_field_fn op_fn;
2661 bool combine_consts;
2662
2663 if (*n_subexprs > 3) {
2664 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2665 return ERR_PTR(-EINVAL);
2666 }
2667
2668 field_op = contains_operator(str, &sep);
2669
2670 if (field_op == FIELD_OP_NONE)
2671 return parse_atom(hist_data, file, str, &flags, var_name);
2672
2673 if (field_op == FIELD_OP_UNARY_MINUS)
2674 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs);
2675
2676 /* Binary operator found, increment n_subexprs */
2677 ++*n_subexprs;
2678
2679 /* Split the expression string at the root operator */
2680 if (!sep)
2681 return ERR_PTR(-EINVAL);
2682
2683 *sep = '\0';
2684 operand1_str = str;
2685 str = sep+1;
2686
2687 /* Binary operator requires both operands */
2688 if (*operand1_str == '\0' || *str == '\0')
2689 return ERR_PTR(-EINVAL);
2690
2691 operand_flags = 0;
2692
2693 /* LHS of string is an expression e.g. a+b in a+b+c */
2694 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs);
2695 if (IS_ERR(operand1))
2696 return ERR_CAST(operand1);
2697
2698 if (operand1->flags & HIST_FIELD_FL_STRING) {
2699 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str));
2700 ret = -EINVAL;
2701 goto free_op1;
2702 }
2703
2704 /* RHS of string is another expression e.g. c in a+b+c */
2705 operand_flags = 0;
2706 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs);
2707 if (IS_ERR(operand2)) {
2708 ret = PTR_ERR(operand2);
2709 goto free_op1;
2710 }
2711 if (operand2->flags & HIST_FIELD_FL_STRING) {
2712 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2713 ret = -EINVAL;
2714 goto free_operands;
2715 }
2716
2717 switch (field_op) {
2718 case FIELD_OP_MINUS:
2719 op_fn = HIST_FIELD_FN_MINUS;
2720 break;
2721 case FIELD_OP_PLUS:
2722 op_fn = HIST_FIELD_FN_PLUS;
2723 break;
2724 case FIELD_OP_DIV:
2725 op_fn = HIST_FIELD_FN_DIV;
2726 break;
2727 case FIELD_OP_MULT:
2728 op_fn = HIST_FIELD_FN_MULT;
2729 break;
2730 default:
2731 ret = -EINVAL;
2732 goto free_operands;
2733 }
2734
2735 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2);
2736 if (ret)
2737 goto free_operands;
2738
2739 operand_flags = var1 ? var1->flags : operand1->flags;
2740 operand2_flags = var2 ? var2->flags : operand2->flags;
2741
2742 /*
2743 * If both operands are constant, the expression can be
2744 * collapsed to a single constant.
2745 */
2746 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST;
2747
2748 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR;
2749
2750 flags |= operand1->flags &
2751 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2752
2753 expr = create_hist_field(hist_data, NULL, flags, var_name);
2754 if (!expr) {
2755 ret = -ENOMEM;
2756 goto free_operands;
2757 }
2758
2759 operand1->read_once = true;
2760 operand2->read_once = true;
2761
2762 /* The operands are now owned and free'd by 'expr' */
2763 expr->operands[0] = operand1;
2764 expr->operands[1] = operand2;
2765
2766 if (field_op == FIELD_OP_DIV &&
2767 operand2_flags & HIST_FIELD_FL_CONST) {
2768 u64 divisor = var2 ? var2->constant : operand2->constant;
2769
2770 if (!divisor) {
2771 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str));
2772 ret = -EDOM;
2773 goto free_expr;
2774 }
2775
2776 /*
2777 * Copy the divisor here so we don't have to look it up
2778 * later if this is a var ref
2779 */
2780 operand2->constant = divisor;
2781 op_fn = hist_field_get_div_fn(operand2);
2782 }
2783
2784 expr->fn_num = op_fn;
2785
2786 if (combine_consts) {
2787 if (var1)
2788 expr->operands[0] = var1;
2789 if (var2)
2790 expr->operands[1] = var2;
2791
2792 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL);
2793 expr->fn_num = HIST_FIELD_FN_CONST;
2794
2795 expr->operands[0] = NULL;
2796 expr->operands[1] = NULL;
2797
2798 /*
2799 * var refs won't be destroyed immediately
2800 * See: destroy_hist_field()
2801 */
2802 destroy_hist_field(operand2, 0);
2803 destroy_hist_field(operand1, 0);
2804
2805 expr->name = expr_str(expr, 0);
2806 } else {
2807 /* The operand sizes should be the same, so just pick one */
2808 expr->size = operand1->size;
2809 expr->is_signed = operand1->is_signed;
2810
2811 expr->operator = field_op;
2812 expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
2813 if (!expr->type) {
2814 ret = -ENOMEM;
2815 goto free_expr;
2816 }
2817
2818 expr->name = expr_str(expr, 0);
2819 }
2820
2821 return expr;
2822
2823 free_operands:
2824 destroy_hist_field(operand2, 0);
2825 free_op1:
2826 destroy_hist_field(operand1, 0);
2827 return ERR_PTR(ret);
2828
2829 free_expr:
2830 destroy_hist_field(expr, 0);
2831 return ERR_PTR(ret);
2832 }
2833
2834 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2835 struct trace_event_file *file)
2836 {
2837 struct event_trigger_data *test;
2838
2839 lockdep_assert_held(&event_mutex);
2840
2841 list_for_each_entry(test, &file->triggers, list) {
2842 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2843 if (test->private_data == hist_data)
2844 return test->filter_str;
2845 }
2846 }
2847
2848 return NULL;
2849 }
2850
2851 static struct event_command trigger_hist_cmd;
2852 static int event_hist_trigger_parse(struct event_command *cmd_ops,
2853 struct trace_event_file *file,
2854 char *glob, char *cmd,
2855 char *param_and_filter);
2856
2857 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2858 struct hist_trigger_data *hist_data,
2859 unsigned int n_keys)
2860 {
2861 struct hist_field *target_hist_field, *hist_field;
2862 unsigned int n, i, j;
2863
2864 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2865 return false;
2866
2867 i = hist_data->n_vals;
2868 j = target_hist_data->n_vals;
2869
2870 for (n = 0; n < n_keys; n++) {
2871 hist_field = hist_data->fields[i + n];
2872 target_hist_field = target_hist_data->fields[j + n];
2873
2874 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2875 return false;
2876 if (hist_field->size != target_hist_field->size)
2877 return false;
2878 if (hist_field->is_signed != target_hist_field->is_signed)
2879 return false;
2880 }
2881
2882 return true;
2883 }
2884
2885 static struct hist_trigger_data *
2886 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2887 struct trace_event_file *file)
2888 {
2889 struct hist_trigger_data *hist_data;
2890 struct event_trigger_data *test;
2891 unsigned int n_keys;
2892
2893 lockdep_assert_held(&event_mutex);
2894
2895 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2896
2897 list_for_each_entry(test, &file->triggers, list) {
2898 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2899 hist_data = test->private_data;
2900
2901 if (compatible_keys(target_hist_data, hist_data, n_keys))
2902 return hist_data;
2903 }
2904 }
2905
2906 return NULL;
2907 }
2908
2909 static struct trace_event_file *event_file(struct trace_array *tr,
2910 char *system, char *event_name)
2911 {
2912 struct trace_event_file *file;
2913
2914 file = __find_event_file(tr, system, event_name);
2915 if (!file)
2916 return ERR_PTR(-EINVAL);
2917
2918 return file;
2919 }
2920
2921 static struct hist_field *
2922 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2923 char *system, char *event_name, char *field_name)
2924 {
2925 struct hist_field *event_var;
2926 char *synthetic_name;
2927
2928 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2929 if (!synthetic_name)
2930 return ERR_PTR(-ENOMEM);
2931
2932 strcpy(synthetic_name, "synthetic_");
2933 strcat(synthetic_name, field_name);
2934
2935 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2936
2937 kfree(synthetic_name);
2938
2939 return event_var;
2940 }
2941
2942 /**
2943 * create_field_var_hist - Automatically create a histogram and var for a field
2944 * @target_hist_data: The target hist trigger
2945 * @subsys_name: Optional subsystem name
2946 * @event_name: Optional event name
2947 * @field_name: The name of the field (and the resulting variable)
2948 *
2949 * Hist trigger actions fetch data from variables, not directly from
2950 * events. However, for convenience, users are allowed to directly
2951 * specify an event field in an action, which will be automatically
2952 * converted into a variable on their behalf.
2953 *
2954 * If a user specifies a field on an event that isn't the event the
2955 * histogram currently being defined (the target event histogram), the
2956 * only way that can be accomplished is if a new hist trigger is
2957 * created and the field variable defined on that.
2958 *
2959 * This function creates a new histogram compatible with the target
2960 * event (meaning a histogram with the same key as the target
2961 * histogram), and creates a variable for the specified field, but
2962 * with 'synthetic_' prepended to the variable name in order to avoid
2963 * collision with normal field variables.
2964 *
2965 * Return: The variable created for the field.
2966 */
2967 static struct hist_field *
2968 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2969 char *subsys_name, char *event_name, char *field_name)
2970 {
2971 struct trace_array *tr = target_hist_data->event_file->tr;
2972 struct hist_trigger_data *hist_data;
2973 unsigned int i, n, first = true;
2974 struct field_var_hist *var_hist;
2975 struct trace_event_file *file;
2976 struct hist_field *key_field;
2977 struct hist_field *event_var;
2978 char *saved_filter;
2979 char *cmd;
2980 int ret;
2981
2982 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2983 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2984 return ERR_PTR(-EINVAL);
2985 }
2986
2987 file = event_file(tr, subsys_name, event_name);
2988
2989 if (IS_ERR(file)) {
2990 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name));
2991 ret = PTR_ERR(file);
2992 return ERR_PTR(ret);
2993 }
2994
2995 /*
2996 * Look for a histogram compatible with target. We'll use the
2997 * found histogram specification to create a new matching
2998 * histogram with our variable on it. target_hist_data is not
2999 * yet a registered histogram so we can't use that.
3000 */
3001 hist_data = find_compatible_hist(target_hist_data, file);
3002 if (!hist_data) {
3003 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name));
3004 return ERR_PTR(-EINVAL);
3005 }
3006
3007 /* See if a synthetic field variable has already been created */
3008 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
3009 event_name, field_name);
3010 if (!IS_ERR_OR_NULL(event_var))
3011 return event_var;
3012
3013 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
3014 if (!var_hist)
3015 return ERR_PTR(-ENOMEM);
3016
3017 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
3018 if (!cmd) {
3019 kfree(var_hist);
3020 return ERR_PTR(-ENOMEM);
3021 }
3022
3023 /* Use the same keys as the compatible histogram */
3024 strcat(cmd, "keys=");
3025
3026 for_each_hist_key_field(i, hist_data) {
3027 key_field = hist_data->fields[i];
3028 if (!first)
3029 strcat(cmd, ",");
3030 strcat(cmd, key_field->field->name);
3031 first = false;
3032 }
3033
3034 /* Create the synthetic field variable specification */
3035 strcat(cmd, ":synthetic_");
3036 strcat(cmd, field_name);
3037 strcat(cmd, "=");
3038 strcat(cmd, field_name);
3039
3040 /* Use the same filter as the compatible histogram */
3041 saved_filter = find_trigger_filter(hist_data, file);
3042 if (saved_filter) {
3043 strcat(cmd, " if ");
3044 strcat(cmd, saved_filter);
3045 }
3046
3047 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
3048 if (!var_hist->cmd) {
3049 kfree(cmd);
3050 kfree(var_hist);
3051 return ERR_PTR(-ENOMEM);
3052 }
3053
3054 /* Save the compatible histogram information */
3055 var_hist->hist_data = hist_data;
3056
3057 /* Create the new histogram with our variable */
3058 ret = event_hist_trigger_parse(&trigger_hist_cmd, file,
3059 "", "hist", cmd);
3060 if (ret) {
3061 kfree(cmd);
3062 kfree(var_hist->cmd);
3063 kfree(var_hist);
3064 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name));
3065 return ERR_PTR(ret);
3066 }
3067
3068 kfree(cmd);
3069
3070 /* If we can't find the variable, something went wrong */
3071 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
3072 event_name, field_name);
3073 if (IS_ERR_OR_NULL(event_var)) {
3074 kfree(var_hist->cmd);
3075 kfree(var_hist);
3076 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name));
3077 return ERR_PTR(-EINVAL);
3078 }
3079
3080 n = target_hist_data->n_field_var_hists;
3081 target_hist_data->field_var_hists[n] = var_hist;
3082 target_hist_data->n_field_var_hists++;
3083
3084 return event_var;
3085 }
3086
3087 static struct hist_field *
3088 find_target_event_var(struct hist_trigger_data *hist_data,
3089 char *subsys_name, char *event_name, char *var_name)
3090 {
3091 struct trace_event_file *file = hist_data->event_file;
3092 struct hist_field *hist_field = NULL;
3093
3094 if (subsys_name) {
3095 struct trace_event_call *call;
3096
3097 if (!event_name)
3098 return NULL;
3099
3100 call = file->event_call;
3101
3102 if (strcmp(subsys_name, call->class->system) != 0)
3103 return NULL;
3104
3105 if (strcmp(event_name, trace_event_name(call)) != 0)
3106 return NULL;
3107 }
3108
3109 hist_field = find_var_field(hist_data, var_name);
3110
3111 return hist_field;
3112 }
3113
3114 static inline void __update_field_vars(struct tracing_map_elt *elt,
3115 struct trace_buffer *buffer,
3116 struct ring_buffer_event *rbe,
3117 void *rec,
3118 struct field_var **field_vars,
3119 unsigned int n_field_vars,
3120 unsigned int field_var_str_start)
3121 {
3122 struct hist_elt_data *elt_data = elt->private_data;
3123 unsigned int i, j, var_idx;
3124 u64 var_val;
3125
3126 /* Make sure stacktrace can fit in the string variable length */
3127 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) >= STR_VAR_LEN_MAX);
3128
3129 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
3130 struct field_var *field_var = field_vars[i];
3131 struct hist_field *var = field_var->var;
3132 struct hist_field *val = field_var->val;
3133
3134 var_val = hist_fn_call(val, elt, buffer, rbe, rec);
3135 var_idx = var->var.idx;
3136
3137 if (val->flags & (HIST_FIELD_FL_STRING |
3138 HIST_FIELD_FL_STACKTRACE)) {
3139 char *str = elt_data->field_var_str[j++];
3140 char *val_str = (char *)(uintptr_t)var_val;
3141 unsigned int size;
3142
3143 if (val->flags & HIST_FIELD_FL_STRING) {
3144 size = min(val->size, STR_VAR_LEN_MAX);
3145 strscpy(str, val_str, size);
3146 } else {
3147 char *stack_start = str + sizeof(unsigned long);
3148 int e;
3149
3150 e = stack_trace_save((void *)stack_start,
3151 HIST_STACKTRACE_DEPTH,
3152 HIST_STACKTRACE_SKIP);
3153 if (e < HIST_STACKTRACE_DEPTH - 1)
3154 ((unsigned long *)stack_start)[e] = 0;
3155 *((unsigned long *)str) = e;
3156 }
3157 var_val = (u64)(uintptr_t)str;
3158 }
3159 tracing_map_set_var(elt, var_idx, var_val);
3160 }
3161 }
3162
3163 static void update_field_vars(struct hist_trigger_data *hist_data,
3164 struct tracing_map_elt *elt,
3165 struct trace_buffer *buffer,
3166 struct ring_buffer_event *rbe,
3167 void *rec)
3168 {
3169 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars,
3170 hist_data->n_field_vars, 0);
3171 }
3172
3173 static void save_track_data_vars(struct hist_trigger_data *hist_data,
3174 struct tracing_map_elt *elt,
3175 struct trace_buffer *buffer, void *rec,
3176 struct ring_buffer_event *rbe, void *key,
3177 struct action_data *data, u64 *var_ref_vals)
3178 {
3179 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars,
3180 hist_data->n_save_vars, hist_data->n_field_var_str);
3181 }
3182
3183 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
3184 struct trace_event_file *file,
3185 char *name, int size, const char *type)
3186 {
3187 struct hist_field *var;
3188 int idx;
3189
3190 if (find_var(hist_data, file, name) && !hist_data->remove) {
3191 var = ERR_PTR(-EINVAL);
3192 goto out;
3193 }
3194
3195 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
3196 if (!var) {
3197 var = ERR_PTR(-ENOMEM);
3198 goto out;
3199 }
3200
3201 idx = tracing_map_add_var(hist_data->map);
3202 if (idx < 0) {
3203 kfree(var);
3204 var = ERR_PTR(-EINVAL);
3205 goto out;
3206 }
3207
3208 var->ref = 1;
3209 var->flags = HIST_FIELD_FL_VAR;
3210 var->var.idx = idx;
3211 var->var.hist_data = var->hist_data = hist_data;
3212 var->size = size;
3213 var->var.name = kstrdup(name, GFP_KERNEL);
3214 var->type = kstrdup_const(type, GFP_KERNEL);
3215 if (!var->var.name || !var->type) {
3216 kfree_const(var->type);
3217 kfree(var->var.name);
3218 kfree(var);
3219 var = ERR_PTR(-ENOMEM);
3220 }
3221 out:
3222 return var;
3223 }
3224
3225 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
3226 struct trace_event_file *file,
3227 char *field_name)
3228 {
3229 struct hist_field *val = NULL, *var = NULL;
3230 unsigned long flags = HIST_FIELD_FL_VAR;
3231 struct trace_array *tr = file->tr;
3232 struct field_var *field_var;
3233 int ret = 0;
3234
3235 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
3236 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
3237 ret = -EINVAL;
3238 goto err;
3239 }
3240
3241 val = parse_atom(hist_data, file, field_name, &flags, NULL);
3242 if (IS_ERR(val)) {
3243 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name));
3244 ret = PTR_ERR(val);
3245 goto err;
3246 }
3247
3248 var = create_var(hist_data, file, field_name, val->size, val->type);
3249 if (IS_ERR(var)) {
3250 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name));
3251 kfree(val);
3252 ret = PTR_ERR(var);
3253 goto err;
3254 }
3255
3256 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
3257 if (!field_var) {
3258 kfree(val);
3259 kfree(var);
3260 ret = -ENOMEM;
3261 goto err;
3262 }
3263
3264 field_var->var = var;
3265 field_var->val = val;
3266 out:
3267 return field_var;
3268 err:
3269 field_var = ERR_PTR(ret);
3270 goto out;
3271 }
3272
3273 /**
3274 * create_target_field_var - Automatically create a variable for a field
3275 * @target_hist_data: The target hist trigger
3276 * @subsys_name: Optional subsystem name
3277 * @event_name: Optional event name
3278 * @var_name: The name of the field (and the resulting variable)
3279 *
3280 * Hist trigger actions fetch data from variables, not directly from
3281 * events. However, for convenience, users are allowed to directly
3282 * specify an event field in an action, which will be automatically
3283 * converted into a variable on their behalf.
3284 *
3285 * This function creates a field variable with the name var_name on
3286 * the hist trigger currently being defined on the target event. If
3287 * subsys_name and event_name are specified, this function simply
3288 * verifies that they do in fact match the target event subsystem and
3289 * event name.
3290 *
3291 * Return: The variable created for the field.
3292 */
3293 static struct field_var *
3294 create_target_field_var(struct hist_trigger_data *target_hist_data,
3295 char *subsys_name, char *event_name, char *var_name)
3296 {
3297 struct trace_event_file *file = target_hist_data->event_file;
3298
3299 if (subsys_name) {
3300 struct trace_event_call *call;
3301
3302 if (!event_name)
3303 return NULL;
3304
3305 call = file->event_call;
3306
3307 if (strcmp(subsys_name, call->class->system) != 0)
3308 return NULL;
3309
3310 if (strcmp(event_name, trace_event_name(call)) != 0)
3311 return NULL;
3312 }
3313
3314 return create_field_var(target_hist_data, file, var_name);
3315 }
3316
3317 static bool check_track_val_max(u64 track_val, u64 var_val)
3318 {
3319 if (var_val <= track_val)
3320 return false;
3321
3322 return true;
3323 }
3324
3325 static bool check_track_val_changed(u64 track_val, u64 var_val)
3326 {
3327 if (var_val == track_val)
3328 return false;
3329
3330 return true;
3331 }
3332
3333 static u64 get_track_val(struct hist_trigger_data *hist_data,
3334 struct tracing_map_elt *elt,
3335 struct action_data *data)
3336 {
3337 unsigned int track_var_idx = data->track_data.track_var->var.idx;
3338 u64 track_val;
3339
3340 track_val = tracing_map_read_var(elt, track_var_idx);
3341
3342 return track_val;
3343 }
3344
3345 static void save_track_val(struct hist_trigger_data *hist_data,
3346 struct tracing_map_elt *elt,
3347 struct action_data *data, u64 var_val)
3348 {
3349 unsigned int track_var_idx = data->track_data.track_var->var.idx;
3350
3351 tracing_map_set_var(elt, track_var_idx, var_val);
3352 }
3353
3354 static void save_track_data(struct hist_trigger_data *hist_data,
3355 struct tracing_map_elt *elt,
3356 struct trace_buffer *buffer, void *rec,
3357 struct ring_buffer_event *rbe, void *key,
3358 struct action_data *data, u64 *var_ref_vals)
3359 {
3360 if (data->track_data.save_data)
3361 data->track_data.save_data(hist_data, elt, buffer, rec, rbe,
3362 key, data, var_ref_vals);
3363 }
3364
3365 static bool check_track_val(struct tracing_map_elt *elt,
3366 struct action_data *data,
3367 u64 var_val)
3368 {
3369 struct hist_trigger_data *hist_data;
3370 u64 track_val;
3371
3372 hist_data = data->track_data.track_var->hist_data;
3373 track_val = get_track_val(hist_data, elt, data);
3374
3375 return data->track_data.check_val(track_val, var_val);
3376 }
3377
3378 #ifdef CONFIG_TRACER_SNAPSHOT
3379 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
3380 {
3381 /* called with tr->max_lock held */
3382 struct track_data *track_data = tr->cond_snapshot->cond_data;
3383 struct hist_elt_data *elt_data, *track_elt_data;
3384 struct snapshot_context *context = cond_data;
3385 struct action_data *action;
3386 u64 track_val;
3387
3388 if (!track_data)
3389 return false;
3390
3391 action = track_data->action_data;
3392
3393 track_val = get_track_val(track_data->hist_data, context->elt,
3394 track_data->action_data);
3395
3396 if (!action->track_data.check_val(track_data->track_val, track_val))
3397 return false;
3398
3399 track_data->track_val = track_val;
3400 memcpy(track_data->key, context->key, track_data->key_len);
3401
3402 elt_data = context->elt->private_data;
3403 track_elt_data = track_data->elt.private_data;
3404 if (elt_data->comm)
3405 strscpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN);
3406
3407 track_data->updated = true;
3408
3409 return true;
3410 }
3411
3412 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
3413 struct tracing_map_elt *elt,
3414 struct trace_buffer *buffer, void *rec,
3415 struct ring_buffer_event *rbe, void *key,
3416 struct action_data *data,
3417 u64 *var_ref_vals)
3418 {
3419 struct trace_event_file *file = hist_data->event_file;
3420 struct snapshot_context context;
3421
3422 context.elt = elt;
3423 context.key = key;
3424
3425 tracing_snapshot_cond(file->tr, &context);
3426 }
3427
3428 static void hist_trigger_print_key(struct seq_file *m,
3429 struct hist_trigger_data *hist_data,
3430 void *key,
3431 struct tracing_map_elt *elt);
3432
3433 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
3434 {
3435 unsigned int i;
3436
3437 if (!hist_data->n_actions)
3438 return NULL;
3439
3440 for (i = 0; i < hist_data->n_actions; i++) {
3441 struct action_data *data = hist_data->actions[i];
3442
3443 if (data->action == ACTION_SNAPSHOT)
3444 return data;
3445 }
3446
3447 return NULL;
3448 }
3449
3450 static void track_data_snapshot_print(struct seq_file *m,
3451 struct hist_trigger_data *hist_data)
3452 {
3453 struct trace_event_file *file = hist_data->event_file;
3454 struct track_data *track_data;
3455 struct action_data *action;
3456
3457 track_data = tracing_cond_snapshot_data(file->tr);
3458 if (!track_data)
3459 return;
3460
3461 if (!track_data->updated)
3462 return;
3463
3464 action = snapshot_action(hist_data);
3465 if (!action)
3466 return;
3467
3468 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n");
3469 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu",
3470 action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
3471 action->track_data.var_str, track_data->track_val);
3472
3473 seq_puts(m, "\ttriggered by event with key: ");
3474 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt);
3475 seq_putc(m, '\n');
3476 }
3477 #else
3478 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
3479 {
3480 return false;
3481 }
3482 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
3483 struct tracing_map_elt *elt,
3484 struct trace_buffer *buffer, void *rec,
3485 struct ring_buffer_event *rbe, void *key,
3486 struct action_data *data,
3487 u64 *var_ref_vals) {}
3488 static void track_data_snapshot_print(struct seq_file *m,
3489 struct hist_trigger_data *hist_data) {}
3490 #endif /* CONFIG_TRACER_SNAPSHOT */
3491
3492 static void track_data_print(struct seq_file *m,
3493 struct hist_trigger_data *hist_data,
3494 struct tracing_map_elt *elt,
3495 struct action_data *data)
3496 {
3497 u64 track_val = get_track_val(hist_data, elt, data);
3498 unsigned int i, save_var_idx;
3499
3500 if (data->handler == HANDLER_ONMAX)
3501 seq_printf(m, "\n\tmax: %10llu", track_val);
3502 else if (data->handler == HANDLER_ONCHANGE)
3503 seq_printf(m, "\n\tchanged: %10llu", track_val);
3504
3505 if (data->action == ACTION_SNAPSHOT)
3506 return;
3507
3508 for (i = 0; i < hist_data->n_save_vars; i++) {
3509 struct hist_field *save_val = hist_data->save_vars[i]->val;
3510 struct hist_field *save_var = hist_data->save_vars[i]->var;
3511 u64 val;
3512
3513 save_var_idx = save_var->var.idx;
3514
3515 val = tracing_map_read_var(elt, save_var_idx);
3516
3517 if (save_val->flags & HIST_FIELD_FL_STRING) {
3518 seq_printf(m, " %s: %-32s", save_var->var.name,
3519 (char *)(uintptr_t)(val));
3520 } else
3521 seq_printf(m, " %s: %10llu", save_var->var.name, val);
3522 }
3523 }
3524
3525 static void ontrack_action(struct hist_trigger_data *hist_data,
3526 struct tracing_map_elt *elt,
3527 struct trace_buffer *buffer, void *rec,
3528 struct ring_buffer_event *rbe, void *key,
3529 struct action_data *data, u64 *var_ref_vals)
3530 {
3531 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx];
3532
3533 if (check_track_val(elt, data, var_val)) {
3534 save_track_val(hist_data, elt, data, var_val);
3535 save_track_data(hist_data, elt, buffer, rec, rbe,
3536 key, data, var_ref_vals);
3537 }
3538 }
3539
3540 static void action_data_destroy(struct action_data *data)
3541 {
3542 unsigned int i;
3543
3544 lockdep_assert_held(&event_mutex);
3545
3546 kfree(data->action_name);
3547
3548 for (i = 0; i < data->n_params; i++)
3549 kfree(data->params[i]);
3550
3551 if (data->synth_event)
3552 data->synth_event->ref--;
3553
3554 kfree(data->synth_event_name);
3555
3556 kfree(data);
3557 }
3558
3559 static void track_data_destroy(struct hist_trigger_data *hist_data,
3560 struct action_data *data)
3561 {
3562 struct trace_event_file *file = hist_data->event_file;
3563
3564 destroy_hist_field(data->track_data.track_var, 0);
3565
3566 if (data->action == ACTION_SNAPSHOT) {
3567 struct track_data *track_data;
3568
3569 track_data = tracing_cond_snapshot_data(file->tr);
3570 if (track_data && track_data->hist_data == hist_data) {
3571 tracing_snapshot_cond_disable(file->tr);
3572 track_data_free(track_data);
3573 }
3574 }
3575
3576 kfree(data->track_data.var_str);
3577
3578 action_data_destroy(data);
3579 }
3580
3581 static int action_create(struct hist_trigger_data *hist_data,
3582 struct action_data *data);
3583
3584 static int track_data_create(struct hist_trigger_data *hist_data,
3585 struct action_data *data)
3586 {
3587 struct hist_field *var_field, *ref_field, *track_var = NULL;
3588 struct trace_event_file *file = hist_data->event_file;
3589 struct trace_array *tr = file->tr;
3590 char *track_data_var_str;
3591 int ret = 0;
3592
3593 track_data_var_str = data->track_data.var_str;
3594 if (track_data_var_str[0] != '$') {
3595 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str));
3596 return -EINVAL;
3597 }
3598 track_data_var_str++;
3599
3600 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str);
3601 if (!var_field) {
3602 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str));
3603 return -EINVAL;
3604 }
3605
3606 ref_field = create_var_ref(hist_data, var_field, NULL, NULL);
3607 if (!ref_field)
3608 return -ENOMEM;
3609
3610 data->track_data.var_ref = ref_field;
3611
3612 if (data->handler == HANDLER_ONMAX)
3613 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64");
3614 if (IS_ERR(track_var)) {
3615 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3616 ret = PTR_ERR(track_var);
3617 goto out;
3618 }
3619
3620 if (data->handler == HANDLER_ONCHANGE)
3621 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64");
3622 if (IS_ERR(track_var)) {
3623 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3624 ret = PTR_ERR(track_var);
3625 goto out;
3626 }
3627 data->track_data.track_var = track_var;
3628
3629 ret = action_create(hist_data, data);
3630 out:
3631 return ret;
3632 }
3633
3634 static int parse_action_params(struct trace_array *tr, char *params,
3635 struct action_data *data)
3636 {
3637 char *param, *saved_param;
3638 bool first_param = true;
3639 int ret = 0;
3640
3641 while (params) {
3642 if (data->n_params >= SYNTH_FIELDS_MAX) {
3643 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0);
3644 ret = -EINVAL;
3645 goto out;
3646 }
3647
3648 param = strsep(&params, ",");
3649 if (!param) {
3650 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0);
3651 ret = -EINVAL;
3652 goto out;
3653 }
3654
3655 param = strstrip(param);
3656 if (strlen(param) < 2) {
3657 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param));
3658 ret = -EINVAL;
3659 goto out;
3660 }
3661
3662 saved_param = kstrdup(param, GFP_KERNEL);
3663 if (!saved_param) {
3664 ret = -ENOMEM;
3665 goto out;
3666 }
3667
3668 if (first_param && data->use_trace_keyword) {
3669 data->synth_event_name = saved_param;
3670 first_param = false;
3671 continue;
3672 }
3673 first_param = false;
3674
3675 data->params[data->n_params++] = saved_param;
3676 }
3677 out:
3678 return ret;
3679 }
3680
3681 static int action_parse(struct trace_array *tr, char *str, struct action_data *data,
3682 enum handler_id handler)
3683 {
3684 char *action_name;
3685 int ret = 0;
3686
3687 strsep(&str, ".");
3688 if (!str) {
3689 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3690 ret = -EINVAL;
3691 goto out;
3692 }
3693
3694 action_name = strsep(&str, "(");
3695 if (!action_name || !str) {
3696 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3697 ret = -EINVAL;
3698 goto out;
3699 }
3700
3701 if (str_has_prefix(action_name, "save")) {
3702 char *params = strsep(&str, ")");
3703
3704 if (!params) {
3705 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0);
3706 ret = -EINVAL;
3707 goto out;
3708 }
3709
3710 ret = parse_action_params(tr, params, data);
3711 if (ret)
3712 goto out;
3713
3714 if (handler == HANDLER_ONMAX)
3715 data->track_data.check_val = check_track_val_max;
3716 else if (handler == HANDLER_ONCHANGE)
3717 data->track_data.check_val = check_track_val_changed;
3718 else {
3719 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3720 ret = -EINVAL;
3721 goto out;
3722 }
3723
3724 data->track_data.save_data = save_track_data_vars;
3725 data->fn = ontrack_action;
3726 data->action = ACTION_SAVE;
3727 } else if (str_has_prefix(action_name, "snapshot")) {
3728 char *params = strsep(&str, ")");
3729
3730 if (!str) {
3731 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params));
3732 ret = -EINVAL;
3733 goto out;
3734 }
3735
3736 if (handler == HANDLER_ONMAX)
3737 data->track_data.check_val = check_track_val_max;
3738 else if (handler == HANDLER_ONCHANGE)
3739 data->track_data.check_val = check_track_val_changed;
3740 else {
3741 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3742 ret = -EINVAL;
3743 goto out;
3744 }
3745
3746 data->track_data.save_data = save_track_data_snapshot;
3747 data->fn = ontrack_action;
3748 data->action = ACTION_SNAPSHOT;
3749 } else {
3750 char *params = strsep(&str, ")");
3751
3752 if (str_has_prefix(action_name, "trace"))
3753 data->use_trace_keyword = true;
3754
3755 if (params) {
3756 ret = parse_action_params(tr, params, data);
3757 if (ret)
3758 goto out;
3759 }
3760
3761 if (handler == HANDLER_ONMAX)
3762 data->track_data.check_val = check_track_val_max;
3763 else if (handler == HANDLER_ONCHANGE)
3764 data->track_data.check_val = check_track_val_changed;
3765
3766 if (handler != HANDLER_ONMATCH) {
3767 data->track_data.save_data = action_trace;
3768 data->fn = ontrack_action;
3769 } else
3770 data->fn = action_trace;
3771
3772 data->action = ACTION_TRACE;
3773 }
3774
3775 data->action_name = kstrdup(action_name, GFP_KERNEL);
3776 if (!data->action_name) {
3777 ret = -ENOMEM;
3778 goto out;
3779 }
3780
3781 data->handler = handler;
3782 out:
3783 return ret;
3784 }
3785
3786 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data,
3787 char *str, enum handler_id handler)
3788 {
3789 struct action_data *data;
3790 int ret = -EINVAL;
3791 char *var_str;
3792
3793 data = kzalloc(sizeof(*data), GFP_KERNEL);
3794 if (!data)
3795 return ERR_PTR(-ENOMEM);
3796
3797 var_str = strsep(&str, ")");
3798 if (!var_str || !str) {
3799 ret = -EINVAL;
3800 goto free;
3801 }
3802
3803 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL);
3804 if (!data->track_data.var_str) {
3805 ret = -ENOMEM;
3806 goto free;
3807 }
3808
3809 ret = action_parse(hist_data->event_file->tr, str, data, handler);
3810 if (ret)
3811 goto free;
3812 out:
3813 return data;
3814 free:
3815 track_data_destroy(hist_data, data);
3816 data = ERR_PTR(ret);
3817 goto out;
3818 }
3819
3820 static void onmatch_destroy(struct action_data *data)
3821 {
3822 kfree(data->match_data.event);
3823 kfree(data->match_data.event_system);
3824
3825 action_data_destroy(data);
3826 }
3827
3828 static void destroy_field_var(struct field_var *field_var)
3829 {
3830 if (!field_var)
3831 return;
3832
3833 destroy_hist_field(field_var->var, 0);
3834 destroy_hist_field(field_var->val, 0);
3835
3836 kfree(field_var);
3837 }
3838
3839 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3840 {
3841 unsigned int i;
3842
3843 for (i = 0; i < hist_data->n_field_vars; i++)
3844 destroy_field_var(hist_data->field_vars[i]);
3845
3846 for (i = 0; i < hist_data->n_save_vars; i++)
3847 destroy_field_var(hist_data->save_vars[i]);
3848 }
3849
3850 static void save_field_var(struct hist_trigger_data *hist_data,
3851 struct field_var *field_var)
3852 {
3853 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3854
3855 /* Stack traces are saved in the string storage too */
3856 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE))
3857 hist_data->n_field_var_str++;
3858 }
3859
3860
3861 static int check_synth_field(struct synth_event *event,
3862 struct hist_field *hist_field,
3863 unsigned int field_pos)
3864 {
3865 struct synth_field *field;
3866
3867 if (field_pos >= event->n_fields)
3868 return -EINVAL;
3869
3870 field = event->fields[field_pos];
3871
3872 /*
3873 * A dynamic string synth field can accept static or
3874 * dynamic. A static string synth field can only accept a
3875 * same-sized static string, which is checked for later.
3876 */
3877 if (strstr(hist_field->type, "char[") && field->is_string
3878 && field->is_dynamic)
3879 return 0;
3880
3881 if (strstr(hist_field->type, "long[") && field->is_stack)
3882 return 0;
3883
3884 if (strcmp(field->type, hist_field->type) != 0) {
3885 if (field->size != hist_field->size ||
3886 (!field->is_string && field->is_signed != hist_field->is_signed))
3887 return -EINVAL;
3888 }
3889
3890 return 0;
3891 }
3892
3893 static struct hist_field *
3894 trace_action_find_var(struct hist_trigger_data *hist_data,
3895 struct action_data *data,
3896 char *system, char *event, char *var)
3897 {
3898 struct trace_array *tr = hist_data->event_file->tr;
3899 struct hist_field *hist_field;
3900
3901 var++; /* skip '$' */
3902
3903 hist_field = find_target_event_var(hist_data, system, event, var);
3904 if (!hist_field) {
3905 if (!system && data->handler == HANDLER_ONMATCH) {
3906 system = data->match_data.event_system;
3907 event = data->match_data.event;
3908 }
3909
3910 hist_field = find_event_var(hist_data, system, event, var);
3911 }
3912
3913 if (!hist_field)
3914 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var));
3915
3916 return hist_field;
3917 }
3918
3919 static struct hist_field *
3920 trace_action_create_field_var(struct hist_trigger_data *hist_data,
3921 struct action_data *data, char *system,
3922 char *event, char *var)
3923 {
3924 struct hist_field *hist_field = NULL;
3925 struct field_var *field_var;
3926
3927 /*
3928 * First try to create a field var on the target event (the
3929 * currently being defined). This will create a variable for
3930 * unqualified fields on the target event, or if qualified,
3931 * target fields that have qualified names matching the target.
3932 */
3933 field_var = create_target_field_var(hist_data, system, event, var);
3934
3935 if (field_var && !IS_ERR(field_var)) {
3936 save_field_var(hist_data, field_var);
3937 hist_field = field_var->var;
3938 } else {
3939 field_var = NULL;
3940 /*
3941 * If no explicit system.event is specified, default to
3942 * looking for fields on the onmatch(system.event.xxx)
3943 * event.
3944 */
3945 if (!system && data->handler == HANDLER_ONMATCH) {
3946 system = data->match_data.event_system;
3947 event = data->match_data.event;
3948 }
3949
3950 if (!event)
3951 goto free;
3952 /*
3953 * At this point, we're looking at a field on another
3954 * event. Because we can't modify a hist trigger on
3955 * another event to add a variable for a field, we need
3956 * to create a new trigger on that event and create the
3957 * variable at the same time.
3958 */
3959 hist_field = create_field_var_hist(hist_data, system, event, var);
3960 if (IS_ERR(hist_field))
3961 goto free;
3962 }
3963 out:
3964 return hist_field;
3965 free:
3966 destroy_field_var(field_var);
3967 hist_field = NULL;
3968 goto out;
3969 }
3970
3971 static int trace_action_create(struct hist_trigger_data *hist_data,
3972 struct action_data *data)
3973 {
3974 struct trace_array *tr = hist_data->event_file->tr;
3975 char *event_name, *param, *system = NULL;
3976 struct hist_field *hist_field, *var_ref;
3977 unsigned int i;
3978 unsigned int field_pos = 0;
3979 struct synth_event *event;
3980 char *synth_event_name;
3981 int var_ref_idx, ret = 0;
3982
3983 lockdep_assert_held(&event_mutex);
3984
3985 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */
3986 if (data->n_params > SYNTH_FIELDS_MAX)
3987 return -EINVAL;
3988
3989 if (data->use_trace_keyword)
3990 synth_event_name = data->synth_event_name;
3991 else
3992 synth_event_name = data->action_name;
3993
3994 event = find_synth_event(synth_event_name);
3995 if (!event) {
3996 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name));
3997 return -EINVAL;
3998 }
3999
4000 event->ref++;
4001
4002 for (i = 0; i < data->n_params; i++) {
4003 char *p;
4004
4005 p = param = kstrdup(data->params[i], GFP_KERNEL);
4006 if (!param) {
4007 ret = -ENOMEM;
4008 goto err;
4009 }
4010
4011 system = strsep(&param, ".");
4012 if (!param) {
4013 param = (char *)system;
4014 system = event_name = NULL;
4015 } else {
4016 event_name = strsep(&param, ".");
4017 if (!param) {
4018 kfree(p);
4019 ret = -EINVAL;
4020 goto err;
4021 }
4022 }
4023
4024 if (param[0] == '$')
4025 hist_field = trace_action_find_var(hist_data, data,
4026 system, event_name,
4027 param);
4028 else
4029 hist_field = trace_action_create_field_var(hist_data,
4030 data,
4031 system,
4032 event_name,
4033 param);
4034
4035 if (!hist_field) {
4036 kfree(p);
4037 ret = -EINVAL;
4038 goto err;
4039 }
4040
4041 if (check_synth_field(event, hist_field, field_pos) == 0) {
4042 var_ref = create_var_ref(hist_data, hist_field,
4043 system, event_name);
4044 if (!var_ref) {
4045 kfree(p);
4046 ret = -ENOMEM;
4047 goto err;
4048 }
4049
4050 var_ref_idx = find_var_ref_idx(hist_data, var_ref);
4051 if (WARN_ON(var_ref_idx < 0)) {
4052 kfree(p);
4053 ret = var_ref_idx;
4054 goto err;
4055 }
4056
4057 data->var_ref_idx[i] = var_ref_idx;
4058
4059 field_pos++;
4060 kfree(p);
4061 continue;
4062 }
4063
4064 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param));
4065 kfree(p);
4066 ret = -EINVAL;
4067 goto err;
4068 }
4069
4070 if (field_pos != event->n_fields) {
4071 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name));
4072 ret = -EINVAL;
4073 goto err;
4074 }
4075
4076 data->synth_event = event;
4077 out:
4078 return ret;
4079 err:
4080 event->ref--;
4081
4082 goto out;
4083 }
4084
4085 static int action_create(struct hist_trigger_data *hist_data,
4086 struct action_data *data)
4087 {
4088 struct trace_event_file *file = hist_data->event_file;
4089 struct trace_array *tr = file->tr;
4090 struct track_data *track_data;
4091 struct field_var *field_var;
4092 unsigned int i;
4093 char *param;
4094 int ret = 0;
4095
4096 if (data->action == ACTION_TRACE)
4097 return trace_action_create(hist_data, data);
4098
4099 if (data->action == ACTION_SNAPSHOT) {
4100 track_data = track_data_alloc(hist_data->key_size, data, hist_data);
4101 if (IS_ERR(track_data)) {
4102 ret = PTR_ERR(track_data);
4103 goto out;
4104 }
4105
4106 ret = tracing_snapshot_cond_enable(file->tr, track_data,
4107 cond_snapshot_update);
4108 if (ret)
4109 track_data_free(track_data);
4110
4111 goto out;
4112 }
4113
4114 if (data->action == ACTION_SAVE) {
4115 if (hist_data->n_save_vars) {
4116 ret = -EEXIST;
4117 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0);
4118 goto out;
4119 }
4120
4121 for (i = 0; i < data->n_params; i++) {
4122 param = kstrdup(data->params[i], GFP_KERNEL);
4123 if (!param) {
4124 ret = -ENOMEM;
4125 goto out;
4126 }
4127
4128 field_var = create_target_field_var(hist_data, NULL, NULL, param);
4129 if (IS_ERR(field_var)) {
4130 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL,
4131 errpos(param));
4132 ret = PTR_ERR(field_var);
4133 kfree(param);
4134 goto out;
4135 }
4136
4137 hist_data->save_vars[hist_data->n_save_vars++] = field_var;
4138 if (field_var->val->flags &
4139 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE))
4140 hist_data->n_save_var_str++;
4141 kfree(param);
4142 }
4143 }
4144 out:
4145 return ret;
4146 }
4147
4148 static int onmatch_create(struct hist_trigger_data *hist_data,
4149 struct action_data *data)
4150 {
4151 return action_create(hist_data, data);
4152 }
4153
4154 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
4155 {
4156 char *match_event, *match_event_system;
4157 struct action_data *data;
4158 int ret = -EINVAL;
4159
4160 data = kzalloc(sizeof(*data), GFP_KERNEL);
4161 if (!data)
4162 return ERR_PTR(-ENOMEM);
4163
4164 match_event = strsep(&str, ")");
4165 if (!match_event || !str) {
4166 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event));
4167 goto free;
4168 }
4169
4170 match_event_system = strsep(&match_event, ".");
4171 if (!match_event) {
4172 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system));
4173 goto free;
4174 }
4175
4176 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
4177 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event));
4178 goto free;
4179 }
4180
4181 data->match_data.event = kstrdup(match_event, GFP_KERNEL);
4182 if (!data->match_data.event) {
4183 ret = -ENOMEM;
4184 goto free;
4185 }
4186
4187 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL);
4188 if (!data->match_data.event_system) {
4189 ret = -ENOMEM;
4190 goto free;
4191 }
4192
4193 ret = action_parse(tr, str, data, HANDLER_ONMATCH);
4194 if (ret)
4195 goto free;
4196 out:
4197 return data;
4198 free:
4199 onmatch_destroy(data);
4200 data = ERR_PTR(ret);
4201 goto out;
4202 }
4203
4204 static int create_hitcount_val(struct hist_trigger_data *hist_data)
4205 {
4206 hist_data->fields[HITCOUNT_IDX] =
4207 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
4208 if (!hist_data->fields[HITCOUNT_IDX])
4209 return -ENOMEM;
4210
4211 hist_data->n_vals++;
4212 hist_data->n_fields++;
4213
4214 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
4215 return -EINVAL;
4216
4217 return 0;
4218 }
4219
4220 static int __create_val_field(struct hist_trigger_data *hist_data,
4221 unsigned int val_idx,
4222 struct trace_event_file *file,
4223 char *var_name, char *field_str,
4224 unsigned long flags)
4225 {
4226 struct hist_field *hist_field;
4227 int ret = 0, n_subexprs = 0;
4228
4229 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs);
4230 if (IS_ERR(hist_field)) {
4231 ret = PTR_ERR(hist_field);
4232 goto out;
4233 }
4234
4235 /* values and variables should not have some modifiers */
4236 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4237 /* Variable */
4238 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT |
4239 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2))
4240 goto err;
4241 } else {
4242 /* Value */
4243 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT |
4244 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 |
4245 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET |
4246 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE))
4247 goto err;
4248 }
4249
4250 hist_data->fields[val_idx] = hist_field;
4251
4252 ++hist_data->n_vals;
4253 ++hist_data->n_fields;
4254
4255 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
4256 ret = -EINVAL;
4257 out:
4258 return ret;
4259 err:
4260 hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str));
4261 return -EINVAL;
4262 }
4263
4264 static int create_val_field(struct hist_trigger_data *hist_data,
4265 unsigned int val_idx,
4266 struct trace_event_file *file,
4267 char *field_str)
4268 {
4269 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
4270 return -EINVAL;
4271
4272 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
4273 }
4274
4275 static const char no_comm[] = "(no comm)";
4276
4277 static u64 hist_field_execname(struct hist_field *hist_field,
4278 struct tracing_map_elt *elt,
4279 struct trace_buffer *buffer,
4280 struct ring_buffer_event *rbe,
4281 void *event)
4282 {
4283 struct hist_elt_data *elt_data;
4284
4285 if (WARN_ON_ONCE(!elt))
4286 return (u64)(unsigned long)no_comm;
4287
4288 elt_data = elt->private_data;
4289
4290 if (WARN_ON_ONCE(!elt_data->comm))
4291 return (u64)(unsigned long)no_comm;
4292
4293 return (u64)(unsigned long)(elt_data->comm);
4294 }
4295
4296 static u64 hist_field_stack(struct hist_field *hist_field,
4297 struct tracing_map_elt *elt,
4298 struct trace_buffer *buffer,
4299 struct ring_buffer_event *rbe,
4300 void *event)
4301 {
4302 u32 str_item = *(u32 *)(event + hist_field->field->offset);
4303 int str_loc = str_item & 0xffff;
4304 char *addr = (char *)(event + str_loc);
4305
4306 return (u64)(unsigned long)addr;
4307 }
4308
4309 static u64 hist_fn_call(struct hist_field *hist_field,
4310 struct tracing_map_elt *elt,
4311 struct trace_buffer *buffer,
4312 struct ring_buffer_event *rbe,
4313 void *event)
4314 {
4315 switch (hist_field->fn_num) {
4316 case HIST_FIELD_FN_VAR_REF:
4317 return hist_field_var_ref(hist_field, elt, buffer, rbe, event);
4318 case HIST_FIELD_FN_COUNTER:
4319 return hist_field_counter(hist_field, elt, buffer, rbe, event);
4320 case HIST_FIELD_FN_CONST:
4321 return hist_field_const(hist_field, elt, buffer, rbe, event);
4322 case HIST_FIELD_FN_LOG2:
4323 return hist_field_log2(hist_field, elt, buffer, rbe, event);
4324 case HIST_FIELD_FN_BUCKET:
4325 return hist_field_bucket(hist_field, elt, buffer, rbe, event);
4326 case HIST_FIELD_FN_TIMESTAMP:
4327 return hist_field_timestamp(hist_field, elt, buffer, rbe, event);
4328 case HIST_FIELD_FN_CPU:
4329 return hist_field_cpu(hist_field, elt, buffer, rbe, event);
4330 case HIST_FIELD_FN_STRING:
4331 return hist_field_string(hist_field, elt, buffer, rbe, event);
4332 case HIST_FIELD_FN_DYNSTRING:
4333 return hist_field_dynstring(hist_field, elt, buffer, rbe, event);
4334 case HIST_FIELD_FN_RELDYNSTRING:
4335 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event);
4336 case HIST_FIELD_FN_PSTRING:
4337 return hist_field_pstring(hist_field, elt, buffer, rbe, event);
4338 case HIST_FIELD_FN_S64:
4339 return hist_field_s64(hist_field, elt, buffer, rbe, event);
4340 case HIST_FIELD_FN_U64:
4341 return hist_field_u64(hist_field, elt, buffer, rbe, event);
4342 case HIST_FIELD_FN_S32:
4343 return hist_field_s32(hist_field, elt, buffer, rbe, event);
4344 case HIST_FIELD_FN_U32:
4345 return hist_field_u32(hist_field, elt, buffer, rbe, event);
4346 case HIST_FIELD_FN_S16:
4347 return hist_field_s16(hist_field, elt, buffer, rbe, event);
4348 case HIST_FIELD_FN_U16:
4349 return hist_field_u16(hist_field, elt, buffer, rbe, event);
4350 case HIST_FIELD_FN_S8:
4351 return hist_field_s8(hist_field, elt, buffer, rbe, event);
4352 case HIST_FIELD_FN_U8:
4353 return hist_field_u8(hist_field, elt, buffer, rbe, event);
4354 case HIST_FIELD_FN_UMINUS:
4355 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event);
4356 case HIST_FIELD_FN_MINUS:
4357 return hist_field_minus(hist_field, elt, buffer, rbe, event);
4358 case HIST_FIELD_FN_PLUS:
4359 return hist_field_plus(hist_field, elt, buffer, rbe, event);
4360 case HIST_FIELD_FN_DIV:
4361 return hist_field_div(hist_field, elt, buffer, rbe, event);
4362 case HIST_FIELD_FN_MULT:
4363 return hist_field_mult(hist_field, elt, buffer, rbe, event);
4364 case HIST_FIELD_FN_DIV_POWER2:
4365 return div_by_power_of_two(hist_field, elt, buffer, rbe, event);
4366 case HIST_FIELD_FN_DIV_NOT_POWER2:
4367 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event);
4368 case HIST_FIELD_FN_DIV_MULT_SHIFT:
4369 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event);
4370 case HIST_FIELD_FN_EXECNAME:
4371 return hist_field_execname(hist_field, elt, buffer, rbe, event);
4372 case HIST_FIELD_FN_STACK:
4373 return hist_field_stack(hist_field, elt, buffer, rbe, event);
4374 default:
4375 return 0;
4376 }
4377 }
4378
4379 /* Convert a var that points to common_pid.execname to a string */
4380 static void update_var_execname(struct hist_field *hist_field)
4381 {
4382 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR |
4383 HIST_FIELD_FL_EXECNAME;
4384 hist_field->size = MAX_FILTER_STR_VAL;
4385 hist_field->is_signed = 0;
4386
4387 kfree_const(hist_field->type);
4388 hist_field->type = "char[]";
4389
4390 hist_field->fn_num = HIST_FIELD_FN_EXECNAME;
4391 }
4392
4393 static int create_var_field(struct hist_trigger_data *hist_data,
4394 unsigned int val_idx,
4395 struct trace_event_file *file,
4396 char *var_name, char *expr_str)
4397 {
4398 struct trace_array *tr = hist_data->event_file->tr;
4399 unsigned long flags = 0;
4400 int ret;
4401
4402 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
4403 return -EINVAL;
4404
4405 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
4406 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name));
4407 return -EINVAL;
4408 }
4409
4410 flags |= HIST_FIELD_FL_VAR;
4411 hist_data->n_vars++;
4412 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
4413 return -EINVAL;
4414
4415 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
4416
4417 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME)
4418 update_var_execname(hist_data->fields[val_idx]);
4419
4420 if (!ret && hist_data->fields[val_idx]->flags &
4421 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE))
4422 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
4423
4424 return ret;
4425 }
4426
4427 static int create_val_fields(struct hist_trigger_data *hist_data,
4428 struct trace_event_file *file)
4429 {
4430 unsigned int i, j = 1, n_hitcount = 0;
4431 char *fields_str, *field_str;
4432 int ret;
4433
4434 ret = create_hitcount_val(hist_data);
4435 if (ret)
4436 goto out;
4437
4438 fields_str = hist_data->attrs->vals_str;
4439 if (!fields_str)
4440 goto out;
4441
4442 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
4443 j < TRACING_MAP_VALS_MAX; i++) {
4444 field_str = strsep(&fields_str, ",");
4445 if (!field_str)
4446 break;
4447
4448 if (strcmp(field_str, "hitcount") == 0) {
4449 if (!n_hitcount++)
4450 continue;
4451 }
4452
4453 ret = create_val_field(hist_data, j++, file, field_str);
4454 if (ret)
4455 goto out;
4456 }
4457
4458 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
4459 ret = -EINVAL;
4460 out:
4461 /* There is only raw hitcount but nohitcount suppresses it. */
4462 if (j == 1 && hist_data->attrs->no_hitcount) {
4463 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0);
4464 ret = -ENOENT;
4465 }
4466
4467 return ret;
4468 }
4469
4470 static int create_key_field(struct hist_trigger_data *hist_data,
4471 unsigned int key_idx,
4472 unsigned int key_offset,
4473 struct trace_event_file *file,
4474 char *field_str)
4475 {
4476 struct trace_array *tr = hist_data->event_file->tr;
4477 struct hist_field *hist_field = NULL;
4478 unsigned long flags = 0;
4479 unsigned int key_size;
4480 int ret = 0, n_subexprs = 0;
4481
4482 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
4483 return -EINVAL;
4484
4485 flags |= HIST_FIELD_FL_KEY;
4486
4487 if (strcmp(field_str, "stacktrace") == 0) {
4488 flags |= HIST_FIELD_FL_STACKTRACE;
4489 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
4490 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
4491 } else {
4492 hist_field = parse_expr(hist_data, file, field_str, flags,
4493 NULL, &n_subexprs);
4494 if (IS_ERR(hist_field)) {
4495 ret = PTR_ERR(hist_field);
4496 goto out;
4497 }
4498
4499 if (field_has_hist_vars(hist_field, 0)) {
4500 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str));
4501 destroy_hist_field(hist_field, 0);
4502 ret = -EINVAL;
4503 goto out;
4504 }
4505
4506 key_size = hist_field->size;
4507 }
4508
4509 hist_data->fields[key_idx] = hist_field;
4510
4511 key_size = ALIGN(key_size, sizeof(u64));
4512 hist_data->fields[key_idx]->size = key_size;
4513 hist_data->fields[key_idx]->offset = key_offset;
4514
4515 hist_data->key_size += key_size;
4516
4517 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
4518 ret = -EINVAL;
4519 goto out;
4520 }
4521
4522 hist_data->n_keys++;
4523 hist_data->n_fields++;
4524
4525 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
4526 return -EINVAL;
4527
4528 ret = key_size;
4529 out:
4530 return ret;
4531 }
4532
4533 static int create_key_fields(struct hist_trigger_data *hist_data,
4534 struct trace_event_file *file)
4535 {
4536 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
4537 char *fields_str, *field_str;
4538 int ret = -EINVAL;
4539
4540 fields_str = hist_data->attrs->keys_str;
4541 if (!fields_str)
4542 goto out;
4543
4544 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
4545 field_str = strsep(&fields_str, ",");
4546 if (!field_str)
4547 break;
4548 ret = create_key_field(hist_data, i, key_offset,
4549 file, field_str);
4550 if (ret < 0)
4551 goto out;
4552 key_offset += ret;
4553 }
4554 if (fields_str) {
4555 ret = -EINVAL;
4556 goto out;
4557 }
4558 ret = 0;
4559 out:
4560 return ret;
4561 }
4562
4563 static int create_var_fields(struct hist_trigger_data *hist_data,
4564 struct trace_event_file *file)
4565 {
4566 unsigned int i, j = hist_data->n_vals;
4567 int ret = 0;
4568
4569 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
4570
4571 for (i = 0; i < n_vars; i++) {
4572 char *var_name = hist_data->attrs->var_defs.name[i];
4573 char *expr = hist_data->attrs->var_defs.expr[i];
4574
4575 ret = create_var_field(hist_data, j++, file, var_name, expr);
4576 if (ret)
4577 goto out;
4578 }
4579 out:
4580 return ret;
4581 }
4582
4583 static void free_var_defs(struct hist_trigger_data *hist_data)
4584 {
4585 unsigned int i;
4586
4587 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
4588 kfree(hist_data->attrs->var_defs.name[i]);
4589 kfree(hist_data->attrs->var_defs.expr[i]);
4590 }
4591
4592 hist_data->attrs->var_defs.n_vars = 0;
4593 }
4594
4595 static int parse_var_defs(struct hist_trigger_data *hist_data)
4596 {
4597 struct trace_array *tr = hist_data->event_file->tr;
4598 char *s, *str, *var_name, *field_str;
4599 unsigned int i, j, n_vars = 0;
4600 int ret = 0;
4601
4602 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
4603 str = hist_data->attrs->assignment_str[i];
4604 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
4605 field_str = strsep(&str, ",");
4606 if (!field_str)
4607 break;
4608
4609 var_name = strsep(&field_str, "=");
4610 if (!var_name || !field_str) {
4611 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT,
4612 errpos(var_name));
4613 ret = -EINVAL;
4614 goto free;
4615 }
4616
4617 if (n_vars == TRACING_MAP_VARS_MAX) {
4618 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name));
4619 ret = -EINVAL;
4620 goto free;
4621 }
4622
4623 s = kstrdup(var_name, GFP_KERNEL);
4624 if (!s) {
4625 ret = -ENOMEM;
4626 goto free;
4627 }
4628 hist_data->attrs->var_defs.name[n_vars] = s;
4629
4630 s = kstrdup(field_str, GFP_KERNEL);
4631 if (!s) {
4632 kfree(hist_data->attrs->var_defs.name[n_vars]);
4633 hist_data->attrs->var_defs.name[n_vars] = NULL;
4634 ret = -ENOMEM;
4635 goto free;
4636 }
4637 hist_data->attrs->var_defs.expr[n_vars++] = s;
4638
4639 hist_data->attrs->var_defs.n_vars = n_vars;
4640 }
4641 }
4642
4643 return ret;
4644 free:
4645 free_var_defs(hist_data);
4646
4647 return ret;
4648 }
4649
4650 static int create_hist_fields(struct hist_trigger_data *hist_data,
4651 struct trace_event_file *file)
4652 {
4653 int ret;
4654
4655 ret = parse_var_defs(hist_data);
4656 if (ret)
4657 return ret;
4658
4659 ret = create_val_fields(hist_data, file);
4660 if (ret)
4661 goto out;
4662
4663 ret = create_var_fields(hist_data, file);
4664 if (ret)
4665 goto out;
4666
4667 ret = create_key_fields(hist_data, file);
4668
4669 out:
4670 free_var_defs(hist_data);
4671
4672 return ret;
4673 }
4674
4675 static int is_descending(struct trace_array *tr, const char *str)
4676 {
4677 if (!str)
4678 return 0;
4679
4680 if (strcmp(str, "descending") == 0)
4681 return 1;
4682
4683 if (strcmp(str, "ascending") == 0)
4684 return 0;
4685
4686 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str));
4687
4688 return -EINVAL;
4689 }
4690
4691 static int create_sort_keys(struct hist_trigger_data *hist_data)
4692 {
4693 struct trace_array *tr = hist_data->event_file->tr;
4694 char *fields_str = hist_data->attrs->sort_key_str;
4695 struct tracing_map_sort_key *sort_key;
4696 int descending, ret = 0;
4697 unsigned int i, j, k;
4698
4699 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4700
4701 if (!fields_str)
4702 goto out;
4703
4704 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4705 struct hist_field *hist_field;
4706 char *field_str, *field_name;
4707 const char *test_name;
4708
4709 sort_key = &hist_data->sort_keys[i];
4710
4711 field_str = strsep(&fields_str, ",");
4712 if (!field_str)
4713 break;
4714
4715 if (!*field_str) {
4716 ret = -EINVAL;
4717 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4718 break;
4719 }
4720
4721 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4722 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort="));
4723 ret = -EINVAL;
4724 break;
4725 }
4726
4727 field_name = strsep(&field_str, ".");
4728 if (!field_name || !*field_name) {
4729 ret = -EINVAL;
4730 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4731 break;
4732 }
4733
4734 if (strcmp(field_name, "hitcount") == 0) {
4735 descending = is_descending(tr, field_str);
4736 if (descending < 0) {
4737 ret = descending;
4738 break;
4739 }
4740 sort_key->descending = descending;
4741 continue;
4742 }
4743
4744 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4745 unsigned int idx;
4746
4747 hist_field = hist_data->fields[j];
4748 if (hist_field->flags & HIST_FIELD_FL_VAR)
4749 continue;
4750
4751 idx = k++;
4752
4753 test_name = hist_field_name(hist_field, 0);
4754
4755 if (strcmp(field_name, test_name) == 0) {
4756 sort_key->field_idx = idx;
4757 descending = is_descending(tr, field_str);
4758 if (descending < 0) {
4759 ret = descending;
4760 goto out;
4761 }
4762 sort_key->descending = descending;
4763 break;
4764 }
4765 }
4766 if (j == hist_data->n_fields) {
4767 ret = -EINVAL;
4768 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name));
4769 break;
4770 }
4771 }
4772
4773 hist_data->n_sort_keys = i;
4774 out:
4775 return ret;
4776 }
4777
4778 static void destroy_actions(struct hist_trigger_data *hist_data)
4779 {
4780 unsigned int i;
4781
4782 for (i = 0; i < hist_data->n_actions; i++) {
4783 struct action_data *data = hist_data->actions[i];
4784
4785 if (data->handler == HANDLER_ONMATCH)
4786 onmatch_destroy(data);
4787 else if (data->handler == HANDLER_ONMAX ||
4788 data->handler == HANDLER_ONCHANGE)
4789 track_data_destroy(hist_data, data);
4790 else
4791 kfree(data);
4792 }
4793 }
4794
4795 static int parse_actions(struct hist_trigger_data *hist_data)
4796 {
4797 struct trace_array *tr = hist_data->event_file->tr;
4798 struct action_data *data;
4799 unsigned int i;
4800 int ret = 0;
4801 char *str;
4802 int len;
4803
4804 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4805 enum handler_id hid = 0;
4806 char *action_str;
4807
4808 str = hist_data->attrs->action_str[i];
4809
4810 if ((len = str_has_prefix(str, "onmatch(")))
4811 hid = HANDLER_ONMATCH;
4812 else if ((len = str_has_prefix(str, "onmax(")))
4813 hid = HANDLER_ONMAX;
4814 else if ((len = str_has_prefix(str, "onchange(")))
4815 hid = HANDLER_ONCHANGE;
4816
4817 action_str = str + len;
4818
4819 switch (hid) {
4820 case HANDLER_ONMATCH:
4821 data = onmatch_parse(tr, action_str);
4822 break;
4823 case HANDLER_ONMAX:
4824 case HANDLER_ONCHANGE:
4825 data = track_data_parse(hist_data, action_str, hid);
4826 break;
4827 default:
4828 data = ERR_PTR(-EINVAL);
4829 break;
4830 }
4831
4832 if (IS_ERR(data)) {
4833 ret = PTR_ERR(data);
4834 break;
4835 }
4836
4837 hist_data->actions[hist_data->n_actions++] = data;
4838 }
4839
4840 return ret;
4841 }
4842
4843 static int create_actions(struct hist_trigger_data *hist_data)
4844 {
4845 struct action_data *data;
4846 unsigned int i;
4847 int ret = 0;
4848
4849 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4850 data = hist_data->actions[i];
4851
4852 if (data->handler == HANDLER_ONMATCH) {
4853 ret = onmatch_create(hist_data, data);
4854 if (ret)
4855 break;
4856 } else if (data->handler == HANDLER_ONMAX ||
4857 data->handler == HANDLER_ONCHANGE) {
4858 ret = track_data_create(hist_data, data);
4859 if (ret)
4860 break;
4861 } else {
4862 ret = -EINVAL;
4863 break;
4864 }
4865 }
4866
4867 return ret;
4868 }
4869
4870 static void print_actions(struct seq_file *m,
4871 struct hist_trigger_data *hist_data,
4872 struct tracing_map_elt *elt)
4873 {
4874 unsigned int i;
4875
4876 for (i = 0; i < hist_data->n_actions; i++) {
4877 struct action_data *data = hist_data->actions[i];
4878
4879 if (data->action == ACTION_SNAPSHOT)
4880 continue;
4881
4882 if (data->handler == HANDLER_ONMAX ||
4883 data->handler == HANDLER_ONCHANGE)
4884 track_data_print(m, hist_data, elt, data);
4885 }
4886 }
4887
4888 static void print_action_spec(struct seq_file *m,
4889 struct hist_trigger_data *hist_data,
4890 struct action_data *data)
4891 {
4892 unsigned int i;
4893
4894 if (data->action == ACTION_SAVE) {
4895 for (i = 0; i < hist_data->n_save_vars; i++) {
4896 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name);
4897 if (i < hist_data->n_save_vars - 1)
4898 seq_puts(m, ",");
4899 }
4900 } else if (data->action == ACTION_TRACE) {
4901 if (data->use_trace_keyword)
4902 seq_printf(m, "%s", data->synth_event_name);
4903 for (i = 0; i < data->n_params; i++) {
4904 if (i || data->use_trace_keyword)
4905 seq_puts(m, ",");
4906 seq_printf(m, "%s", data->params[i]);
4907 }
4908 }
4909 }
4910
4911 static void print_track_data_spec(struct seq_file *m,
4912 struct hist_trigger_data *hist_data,
4913 struct action_data *data)
4914 {
4915 if (data->handler == HANDLER_ONMAX)
4916 seq_puts(m, ":onmax(");
4917 else if (data->handler == HANDLER_ONCHANGE)
4918 seq_puts(m, ":onchange(");
4919 seq_printf(m, "%s", data->track_data.var_str);
4920 seq_printf(m, ").%s(", data->action_name);
4921
4922 print_action_spec(m, hist_data, data);
4923
4924 seq_puts(m, ")");
4925 }
4926
4927 static void print_onmatch_spec(struct seq_file *m,
4928 struct hist_trigger_data *hist_data,
4929 struct action_data *data)
4930 {
4931 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system,
4932 data->match_data.event);
4933
4934 seq_printf(m, "%s(", data->action_name);
4935
4936 print_action_spec(m, hist_data, data);
4937
4938 seq_puts(m, ")");
4939 }
4940
4941 static bool actions_match(struct hist_trigger_data *hist_data,
4942 struct hist_trigger_data *hist_data_test)
4943 {
4944 unsigned int i, j;
4945
4946 if (hist_data->n_actions != hist_data_test->n_actions)
4947 return false;
4948
4949 for (i = 0; i < hist_data->n_actions; i++) {
4950 struct action_data *data = hist_data->actions[i];
4951 struct action_data *data_test = hist_data_test->actions[i];
4952 char *action_name, *action_name_test;
4953
4954 if (data->handler != data_test->handler)
4955 return false;
4956 if (data->action != data_test->action)
4957 return false;
4958
4959 if (data->n_params != data_test->n_params)
4960 return false;
4961
4962 for (j = 0; j < data->n_params; j++) {
4963 if (strcmp(data->params[j], data_test->params[j]) != 0)
4964 return false;
4965 }
4966
4967 if (data->use_trace_keyword)
4968 action_name = data->synth_event_name;
4969 else
4970 action_name = data->action_name;
4971
4972 if (data_test->use_trace_keyword)
4973 action_name_test = data_test->synth_event_name;
4974 else
4975 action_name_test = data_test->action_name;
4976
4977 if (strcmp(action_name, action_name_test) != 0)
4978 return false;
4979
4980 if (data->handler == HANDLER_ONMATCH) {
4981 if (strcmp(data->match_data.event_system,
4982 data_test->match_data.event_system) != 0)
4983 return false;
4984 if (strcmp(data->match_data.event,
4985 data_test->match_data.event) != 0)
4986 return false;
4987 } else if (data->handler == HANDLER_ONMAX ||
4988 data->handler == HANDLER_ONCHANGE) {
4989 if (strcmp(data->track_data.var_str,
4990 data_test->track_data.var_str) != 0)
4991 return false;
4992 }
4993 }
4994
4995 return true;
4996 }
4997
4998
4999 static void print_actions_spec(struct seq_file *m,
5000 struct hist_trigger_data *hist_data)
5001 {
5002 unsigned int i;
5003
5004 for (i = 0; i < hist_data->n_actions; i++) {
5005 struct action_data *data = hist_data->actions[i];
5006
5007 if (data->handler == HANDLER_ONMATCH)
5008 print_onmatch_spec(m, hist_data, data);
5009 else if (data->handler == HANDLER_ONMAX ||
5010 data->handler == HANDLER_ONCHANGE)
5011 print_track_data_spec(m, hist_data, data);
5012 }
5013 }
5014
5015 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
5016 {
5017 unsigned int i;
5018
5019 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5020 kfree(hist_data->field_var_hists[i]->cmd);
5021 kfree(hist_data->field_var_hists[i]);
5022 }
5023 }
5024
5025 static void destroy_hist_data(struct hist_trigger_data *hist_data)
5026 {
5027 if (!hist_data)
5028 return;
5029
5030 destroy_hist_trigger_attrs(hist_data->attrs);
5031 destroy_hist_fields(hist_data);
5032 tracing_map_destroy(hist_data->map);
5033
5034 destroy_actions(hist_data);
5035 destroy_field_vars(hist_data);
5036 destroy_field_var_hists(hist_data);
5037
5038 kfree(hist_data);
5039 }
5040
5041 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
5042 {
5043 struct tracing_map *map = hist_data->map;
5044 struct ftrace_event_field *field;
5045 struct hist_field *hist_field;
5046 int i, idx = 0;
5047
5048 for_each_hist_field(i, hist_data) {
5049 hist_field = hist_data->fields[i];
5050 if (hist_field->flags & HIST_FIELD_FL_KEY) {
5051 tracing_map_cmp_fn_t cmp_fn;
5052
5053 field = hist_field->field;
5054
5055 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
5056 cmp_fn = tracing_map_cmp_none;
5057 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU)
5058 cmp_fn = tracing_map_cmp_num(hist_field->size,
5059 hist_field->is_signed);
5060 else if (is_string_field(field))
5061 cmp_fn = tracing_map_cmp_string;
5062 else
5063 cmp_fn = tracing_map_cmp_num(field->size,
5064 field->is_signed);
5065 idx = tracing_map_add_key_field(map,
5066 hist_field->offset,
5067 cmp_fn);
5068 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
5069 idx = tracing_map_add_sum_field(map);
5070
5071 if (idx < 0)
5072 return idx;
5073
5074 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5075 idx = tracing_map_add_var(map);
5076 if (idx < 0)
5077 return idx;
5078 hist_field->var.idx = idx;
5079 hist_field->var.hist_data = hist_data;
5080 }
5081 }
5082
5083 return 0;
5084 }
5085
5086 static struct hist_trigger_data *
5087 create_hist_data(unsigned int map_bits,
5088 struct hist_trigger_attrs *attrs,
5089 struct trace_event_file *file,
5090 bool remove)
5091 {
5092 const struct tracing_map_ops *map_ops = NULL;
5093 struct hist_trigger_data *hist_data;
5094 int ret = 0;
5095
5096 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
5097 if (!hist_data)
5098 return ERR_PTR(-ENOMEM);
5099
5100 hist_data->attrs = attrs;
5101 hist_data->remove = remove;
5102 hist_data->event_file = file;
5103
5104 ret = parse_actions(hist_data);
5105 if (ret)
5106 goto free;
5107
5108 ret = create_hist_fields(hist_data, file);
5109 if (ret)
5110 goto free;
5111
5112 ret = create_sort_keys(hist_data);
5113 if (ret)
5114 goto free;
5115
5116 map_ops = &hist_trigger_elt_data_ops;
5117
5118 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
5119 map_ops, hist_data);
5120 if (IS_ERR(hist_data->map)) {
5121 ret = PTR_ERR(hist_data->map);
5122 hist_data->map = NULL;
5123 goto free;
5124 }
5125
5126 ret = create_tracing_map_fields(hist_data);
5127 if (ret)
5128 goto free;
5129 out:
5130 return hist_data;
5131 free:
5132 hist_data->attrs = NULL;
5133
5134 destroy_hist_data(hist_data);
5135
5136 hist_data = ERR_PTR(ret);
5137
5138 goto out;
5139 }
5140
5141 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
5142 struct tracing_map_elt *elt,
5143 struct trace_buffer *buffer, void *rec,
5144 struct ring_buffer_event *rbe,
5145 u64 *var_ref_vals)
5146 {
5147 struct hist_elt_data *elt_data;
5148 struct hist_field *hist_field;
5149 unsigned int i, var_idx;
5150 u64 hist_val;
5151
5152 elt_data = elt->private_data;
5153 elt_data->var_ref_vals = var_ref_vals;
5154
5155 for_each_hist_val_field(i, hist_data) {
5156 hist_field = hist_data->fields[i];
5157 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec);
5158 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5159 var_idx = hist_field->var.idx;
5160
5161 if (hist_field->flags &
5162 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) {
5163 unsigned int str_start, var_str_idx, idx;
5164 char *str, *val_str;
5165 unsigned int size;
5166
5167 str_start = hist_data->n_field_var_str +
5168 hist_data->n_save_var_str;
5169 var_str_idx = hist_field->var_str_idx;
5170 idx = str_start + var_str_idx;
5171
5172 str = elt_data->field_var_str[idx];
5173 val_str = (char *)(uintptr_t)hist_val;
5174
5175 if (hist_field->flags & HIST_FIELD_FL_STRING) {
5176 size = min(hist_field->size, STR_VAR_LEN_MAX);
5177 strscpy(str, val_str, size);
5178 } else {
5179 char *stack_start = str + sizeof(unsigned long);
5180 int e;
5181
5182 e = stack_trace_save((void *)stack_start,
5183 HIST_STACKTRACE_DEPTH,
5184 HIST_STACKTRACE_SKIP);
5185 if (e < HIST_STACKTRACE_DEPTH - 1)
5186 ((unsigned long *)stack_start)[e] = 0;
5187 *((unsigned long *)str) = e;
5188 }
5189 hist_val = (u64)(uintptr_t)str;
5190 }
5191 tracing_map_set_var(elt, var_idx, hist_val);
5192 continue;
5193 }
5194 tracing_map_update_sum(elt, i, hist_val);
5195 }
5196
5197 for_each_hist_key_field(i, hist_data) {
5198 hist_field = hist_data->fields[i];
5199 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5200 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec);
5201 var_idx = hist_field->var.idx;
5202 tracing_map_set_var(elt, var_idx, hist_val);
5203 }
5204 }
5205
5206 update_field_vars(hist_data, elt, buffer, rbe, rec);
5207 }
5208
5209 static inline void add_to_key(char *compound_key, void *key,
5210 struct hist_field *key_field, void *rec)
5211 {
5212 size_t size = key_field->size;
5213
5214 if (key_field->flags & HIST_FIELD_FL_STRING) {
5215 struct ftrace_event_field *field;
5216
5217 field = key_field->field;
5218 if (field->filter_type == FILTER_DYN_STRING ||
5219 field->filter_type == FILTER_RDYN_STRING)
5220 size = *(u32 *)(rec + field->offset) >> 16;
5221 else if (field->filter_type == FILTER_STATIC_STRING)
5222 size = field->size;
5223
5224 /* ensure NULL-termination */
5225 if (size > key_field->size - 1)
5226 size = key_field->size - 1;
5227
5228 strncpy(compound_key + key_field->offset, (char *)key, size);
5229 } else
5230 memcpy(compound_key + key_field->offset, key, size);
5231 }
5232
5233 static void
5234 hist_trigger_actions(struct hist_trigger_data *hist_data,
5235 struct tracing_map_elt *elt,
5236 struct trace_buffer *buffer, void *rec,
5237 struct ring_buffer_event *rbe, void *key,
5238 u64 *var_ref_vals)
5239 {
5240 struct action_data *data;
5241 unsigned int i;
5242
5243 for (i = 0; i < hist_data->n_actions; i++) {
5244 data = hist_data->actions[i];
5245 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals);
5246 }
5247 }
5248
5249 static void event_hist_trigger(struct event_trigger_data *data,
5250 struct trace_buffer *buffer, void *rec,
5251 struct ring_buffer_event *rbe)
5252 {
5253 struct hist_trigger_data *hist_data = data->private_data;
5254 bool use_compound_key = (hist_data->n_keys > 1);
5255 unsigned long entries[HIST_STACKTRACE_DEPTH];
5256 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
5257 char compound_key[HIST_KEY_SIZE_MAX];
5258 struct tracing_map_elt *elt = NULL;
5259 struct hist_field *key_field;
5260 u64 field_contents;
5261 void *key = NULL;
5262 unsigned int i;
5263
5264 if (unlikely(!rbe))
5265 return;
5266
5267 memset(compound_key, 0, hist_data->key_size);
5268
5269 for_each_hist_key_field(i, hist_data) {
5270 key_field = hist_data->fields[i];
5271
5272 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
5273 memset(entries, 0, HIST_STACKTRACE_SIZE);
5274 if (key_field->field) {
5275 unsigned long *stack, n_entries;
5276
5277 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec);
5278 stack = (unsigned long *)(long)field_contents;
5279 n_entries = *stack;
5280 memcpy(entries, ++stack, n_entries * sizeof(unsigned long));
5281 } else {
5282 stack_trace_save(entries, HIST_STACKTRACE_DEPTH,
5283 HIST_STACKTRACE_SKIP);
5284 }
5285 key = entries;
5286 } else {
5287 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec);
5288 if (key_field->flags & HIST_FIELD_FL_STRING) {
5289 key = (void *)(unsigned long)field_contents;
5290 use_compound_key = true;
5291 } else
5292 key = (void *)&field_contents;
5293 }
5294
5295 if (use_compound_key)
5296 add_to_key(compound_key, key, key_field, rec);
5297 }
5298
5299 if (use_compound_key)
5300 key = compound_key;
5301
5302 if (hist_data->n_var_refs &&
5303 !resolve_var_refs(hist_data, key, var_ref_vals, false))
5304 return;
5305
5306 elt = tracing_map_insert(hist_data->map, key);
5307 if (!elt)
5308 return;
5309
5310 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals);
5311
5312 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
5313 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals);
5314 }
5315
5316 static void hist_trigger_stacktrace_print(struct seq_file *m,
5317 unsigned long *stacktrace_entries,
5318 unsigned int max_entries)
5319 {
5320 unsigned int spaces = 8;
5321 unsigned int i;
5322
5323 for (i = 0; i < max_entries; i++) {
5324 if (!stacktrace_entries[i])
5325 return;
5326
5327 seq_printf(m, "%*c", 1 + spaces, ' ');
5328 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]);
5329 }
5330 }
5331
5332 static void hist_trigger_print_key(struct seq_file *m,
5333 struct hist_trigger_data *hist_data,
5334 void *key,
5335 struct tracing_map_elt *elt)
5336 {
5337 struct hist_field *key_field;
5338 bool multiline = false;
5339 const char *field_name;
5340 unsigned int i;
5341 u64 uval;
5342
5343 seq_puts(m, "{ ");
5344
5345 for_each_hist_key_field(i, hist_data) {
5346 key_field = hist_data->fields[i];
5347
5348 if (i > hist_data->n_vals)
5349 seq_puts(m, ", ");
5350
5351 field_name = hist_field_name(key_field, 0);
5352
5353 if (key_field->flags & HIST_FIELD_FL_HEX) {
5354 uval = *(u64 *)(key + key_field->offset);
5355 seq_printf(m, "%s: %llx", field_name, uval);
5356 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
5357 uval = *(u64 *)(key + key_field->offset);
5358 seq_printf(m, "%s: [%llx] %-45ps", field_name,
5359 uval, (void *)(uintptr_t)uval);
5360 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
5361 uval = *(u64 *)(key + key_field->offset);
5362 seq_printf(m, "%s: [%llx] %-55pS", field_name,
5363 uval, (void *)(uintptr_t)uval);
5364 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
5365 struct hist_elt_data *elt_data = elt->private_data;
5366 char *comm;
5367
5368 if (WARN_ON_ONCE(!elt_data))
5369 return;
5370
5371 comm = elt_data->comm;
5372
5373 uval = *(u64 *)(key + key_field->offset);
5374 seq_printf(m, "%s: %-16s[%10llu]", field_name,
5375 comm, uval);
5376 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
5377 const char *syscall_name;
5378
5379 uval = *(u64 *)(key + key_field->offset);
5380 syscall_name = get_syscall_name(uval);
5381 if (!syscall_name)
5382 syscall_name = "unknown_syscall";
5383
5384 seq_printf(m, "%s: %-30s[%3llu]", field_name,
5385 syscall_name, uval);
5386 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
5387 if (key_field->field)
5388 seq_printf(m, "%s.stacktrace", key_field->field->name);
5389 else
5390 seq_puts(m, "common_stacktrace:\n");
5391 hist_trigger_stacktrace_print(m,
5392 key + key_field->offset,
5393 HIST_STACKTRACE_DEPTH);
5394 multiline = true;
5395 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
5396 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
5397 *(u64 *)(key + key_field->offset));
5398 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) {
5399 unsigned long buckets = key_field->buckets;
5400 uval = *(u64 *)(key + key_field->offset);
5401 seq_printf(m, "%s: ~ %llu-%llu", field_name,
5402 uval, uval + buckets -1);
5403 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
5404 seq_printf(m, "%s: %-50s", field_name,
5405 (char *)(key + key_field->offset));
5406 } else {
5407 uval = *(u64 *)(key + key_field->offset);
5408 seq_printf(m, "%s: %10llu", field_name, uval);
5409 }
5410 }
5411
5412 if (!multiline)
5413 seq_puts(m, " ");
5414
5415 seq_puts(m, "}");
5416 }
5417
5418 /* Get the 100 times of the percentage of @val in @total */
5419 static inline unsigned int __get_percentage(u64 val, u64 total)
5420 {
5421 if (!total)
5422 goto div0;
5423
5424 if (val < (U64_MAX / 10000))
5425 return (unsigned int)div64_ul(val * 10000, total);
5426
5427 total = div64_u64(total, 10000);
5428 if (!total)
5429 goto div0;
5430
5431 return (unsigned int)div64_ul(val, total);
5432 div0:
5433 return val ? UINT_MAX : 0;
5434 }
5435
5436 #define BAR_CHAR '#'
5437
5438 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max)
5439 {
5440 unsigned int len = __get_percentage(val, max);
5441 int i;
5442
5443 if (len == UINT_MAX) {
5444 snprintf(buf, size, "[ERROR]");
5445 return buf;
5446 }
5447
5448 len = len * size / 10000;
5449 for (i = 0; i < len && i < size; i++)
5450 buf[i] = BAR_CHAR;
5451 while (i < size)
5452 buf[i++] = ' ';
5453 buf[size] = '\0';
5454
5455 return buf;
5456 }
5457
5458 struct hist_val_stat {
5459 u64 max;
5460 u64 total;
5461 };
5462
5463 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx,
5464 const char *field_name, unsigned long flags,
5465 struct hist_val_stat *stats,
5466 struct tracing_map_elt *elt)
5467 {
5468 u64 val = tracing_map_read_sum(elt, idx);
5469 unsigned int pc;
5470 char bar[21];
5471
5472 if (flags & HIST_FIELD_FL_PERCENT) {
5473 pc = __get_percentage(val, stats[idx].total);
5474 if (pc == UINT_MAX)
5475 seq_printf(m, " %s (%%):[ERROR]", field_name);
5476 else
5477 seq_printf(m, " %s (%%): %3u.%02u", field_name,
5478 pc / 100, pc % 100);
5479 } else if (flags & HIST_FIELD_FL_GRAPH) {
5480 seq_printf(m, " %s: %20s", field_name,
5481 __fill_bar_str(bar, 20, val, stats[idx].max));
5482 } else if (flags & HIST_FIELD_FL_HEX) {
5483 seq_printf(m, " %s: %10llx", field_name, val);
5484 } else {
5485 seq_printf(m, " %s: %10llu", field_name, val);
5486 }
5487 }
5488
5489 static void hist_trigger_entry_print(struct seq_file *m,
5490 struct hist_trigger_data *hist_data,
5491 struct hist_val_stat *stats,
5492 void *key,
5493 struct tracing_map_elt *elt)
5494 {
5495 const char *field_name;
5496 unsigned int i = HITCOUNT_IDX;
5497 unsigned long flags;
5498
5499 hist_trigger_print_key(m, hist_data, key, elt);
5500
5501 /* At first, show the raw hitcount if !nohitcount */
5502 if (!hist_data->attrs->no_hitcount)
5503 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt);
5504
5505 for (i = 1; i < hist_data->n_vals; i++) {
5506 field_name = hist_field_name(hist_data->fields[i], 0);
5507 flags = hist_data->fields[i]->flags;
5508 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR)
5509 continue;
5510
5511 seq_puts(m, " ");
5512 hist_trigger_print_val(m, i, field_name, flags, stats, elt);
5513 }
5514
5515 print_actions(m, hist_data, elt);
5516
5517 seq_puts(m, "\n");
5518 }
5519
5520 static int print_entries(struct seq_file *m,
5521 struct hist_trigger_data *hist_data)
5522 {
5523 struct tracing_map_sort_entry **sort_entries = NULL;
5524 struct tracing_map *map = hist_data->map;
5525 int i, j, n_entries;
5526 struct hist_val_stat *stats = NULL;
5527 u64 val;
5528
5529 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
5530 hist_data->n_sort_keys,
5531 &sort_entries);
5532 if (n_entries < 0)
5533 return n_entries;
5534
5535 /* Calculate the max and the total for each field if needed. */
5536 for (j = 0; j < hist_data->n_vals; j++) {
5537 if (!(hist_data->fields[j]->flags &
5538 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH)))
5539 continue;
5540 if (!stats) {
5541 stats = kcalloc(hist_data->n_vals, sizeof(*stats),
5542 GFP_KERNEL);
5543 if (!stats) {
5544 n_entries = -ENOMEM;
5545 goto out;
5546 }
5547 }
5548 for (i = 0; i < n_entries; i++) {
5549 val = tracing_map_read_sum(sort_entries[i]->elt, j);
5550 stats[j].total += val;
5551 if (stats[j].max < val)
5552 stats[j].max = val;
5553 }
5554 }
5555
5556 for (i = 0; i < n_entries; i++)
5557 hist_trigger_entry_print(m, hist_data, stats,
5558 sort_entries[i]->key,
5559 sort_entries[i]->elt);
5560
5561 kfree(stats);
5562 out:
5563 tracing_map_destroy_sort_entries(sort_entries, n_entries);
5564
5565 return n_entries;
5566 }
5567
5568 static void hist_trigger_show(struct seq_file *m,
5569 struct event_trigger_data *data, int n)
5570 {
5571 struct hist_trigger_data *hist_data;
5572 int n_entries;
5573
5574 if (n > 0)
5575 seq_puts(m, "\n\n");
5576
5577 seq_puts(m, "# event histogram\n#\n# trigger info: ");
5578 data->ops->print(m, data);
5579 seq_puts(m, "#\n\n");
5580
5581 hist_data = data->private_data;
5582 n_entries = print_entries(m, hist_data);
5583 if (n_entries < 0)
5584 n_entries = 0;
5585
5586 track_data_snapshot_print(m, hist_data);
5587
5588 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
5589 (u64)atomic64_read(&hist_data->map->hits),
5590 n_entries, (u64)atomic64_read(&hist_data->map->drops));
5591 }
5592
5593 static int hist_show(struct seq_file *m, void *v)
5594 {
5595 struct event_trigger_data *data;
5596 struct trace_event_file *event_file;
5597 int n = 0, ret = 0;
5598
5599 mutex_lock(&event_mutex);
5600
5601 event_file = event_file_file(m->private);
5602 if (unlikely(!event_file)) {
5603 ret = -ENODEV;
5604 goto out_unlock;
5605 }
5606
5607 list_for_each_entry(data, &event_file->triggers, list) {
5608 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5609 hist_trigger_show(m, data, n++);
5610 }
5611
5612 out_unlock:
5613 mutex_unlock(&event_mutex);
5614
5615 return ret;
5616 }
5617
5618 static int event_hist_open(struct inode *inode, struct file *file)
5619 {
5620 int ret;
5621
5622 ret = tracing_open_file_tr(inode, file);
5623 if (ret)
5624 return ret;
5625
5626 /* Clear private_data to avoid warning in single_open() */
5627 file->private_data = NULL;
5628 return single_open(file, hist_show, file);
5629 }
5630
5631 const struct file_operations event_hist_fops = {
5632 .open = event_hist_open,
5633 .read = seq_read,
5634 .llseek = seq_lseek,
5635 .release = tracing_single_release_file_tr,
5636 };
5637
5638 #ifdef CONFIG_HIST_TRIGGERS_DEBUG
5639 static void hist_field_debug_show_flags(struct seq_file *m,
5640 unsigned long flags)
5641 {
5642 seq_puts(m, " flags:\n");
5643
5644 if (flags & HIST_FIELD_FL_KEY)
5645 seq_puts(m, " HIST_FIELD_FL_KEY\n");
5646 else if (flags & HIST_FIELD_FL_HITCOUNT)
5647 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n");
5648 else if (flags & HIST_FIELD_FL_VAR)
5649 seq_puts(m, " HIST_FIELD_FL_VAR\n");
5650 else if (flags & HIST_FIELD_FL_VAR_REF)
5651 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n");
5652 else
5653 seq_puts(m, " VAL: normal u64 value\n");
5654
5655 if (flags & HIST_FIELD_FL_ALIAS)
5656 seq_puts(m, " HIST_FIELD_FL_ALIAS\n");
5657 else if (flags & HIST_FIELD_FL_CONST)
5658 seq_puts(m, " HIST_FIELD_FL_CONST\n");
5659 }
5660
5661 static int hist_field_debug_show(struct seq_file *m,
5662 struct hist_field *field, unsigned long flags)
5663 {
5664 if ((field->flags & flags) != flags) {
5665 seq_printf(m, "ERROR: bad flags - %lx\n", flags);
5666 return -EINVAL;
5667 }
5668
5669 hist_field_debug_show_flags(m, field->flags);
5670 if (field->field)
5671 seq_printf(m, " ftrace_event_field name: %s\n",
5672 field->field->name);
5673
5674 if (field->flags & HIST_FIELD_FL_VAR) {
5675 seq_printf(m, " var.name: %s\n", field->var.name);
5676 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
5677 field->var.idx);
5678 }
5679
5680 if (field->flags & HIST_FIELD_FL_CONST)
5681 seq_printf(m, " constant: %llu\n", field->constant);
5682
5683 if (field->flags & HIST_FIELD_FL_ALIAS)
5684 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
5685 field->var_ref_idx);
5686
5687 if (field->flags & HIST_FIELD_FL_VAR_REF) {
5688 seq_printf(m, " name: %s\n", field->name);
5689 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
5690 field->var.idx);
5691 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data);
5692 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
5693 field->var_ref_idx);
5694 if (field->system)
5695 seq_printf(m, " system: %s\n", field->system);
5696 if (field->event_name)
5697 seq_printf(m, " event_name: %s\n", field->event_name);
5698 }
5699
5700 seq_printf(m, " type: %s\n", field->type);
5701 seq_printf(m, " size: %u\n", field->size);
5702 seq_printf(m, " is_signed: %u\n", field->is_signed);
5703
5704 return 0;
5705 }
5706
5707 static int field_var_debug_show(struct seq_file *m,
5708 struct field_var *field_var, unsigned int i,
5709 bool save_vars)
5710 {
5711 const char *vars_name = save_vars ? "save_vars" : "field_vars";
5712 struct hist_field *field;
5713 int ret = 0;
5714
5715 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i);
5716
5717 field = field_var->var;
5718
5719 seq_printf(m, "\n %s[%d].var:\n", vars_name, i);
5720
5721 hist_field_debug_show_flags(m, field->flags);
5722 seq_printf(m, " var.name: %s\n", field->var.name);
5723 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
5724 field->var.idx);
5725
5726 field = field_var->val;
5727
5728 seq_printf(m, "\n %s[%d].val:\n", vars_name, i);
5729 if (field->field)
5730 seq_printf(m, " ftrace_event_field name: %s\n",
5731 field->field->name);
5732 else {
5733 ret = -EINVAL;
5734 goto out;
5735 }
5736
5737 seq_printf(m, " type: %s\n", field->type);
5738 seq_printf(m, " size: %u\n", field->size);
5739 seq_printf(m, " is_signed: %u\n", field->is_signed);
5740 out:
5741 return ret;
5742 }
5743
5744 static int hist_action_debug_show(struct seq_file *m,
5745 struct action_data *data, int i)
5746 {
5747 int ret = 0;
5748
5749 if (data->handler == HANDLER_ONMAX ||
5750 data->handler == HANDLER_ONCHANGE) {
5751 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i);
5752 ret = hist_field_debug_show(m, data->track_data.var_ref,
5753 HIST_FIELD_FL_VAR_REF);
5754 if (ret)
5755 goto out;
5756
5757 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i);
5758 ret = hist_field_debug_show(m, data->track_data.track_var,
5759 HIST_FIELD_FL_VAR);
5760 if (ret)
5761 goto out;
5762 }
5763
5764 if (data->handler == HANDLER_ONMATCH) {
5765 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n",
5766 i, data->match_data.event_system);
5767 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n",
5768 i, data->match_data.event);
5769 }
5770 out:
5771 return ret;
5772 }
5773
5774 static int hist_actions_debug_show(struct seq_file *m,
5775 struct hist_trigger_data *hist_data)
5776 {
5777 int i, ret = 0;
5778
5779 if (hist_data->n_actions)
5780 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n");
5781
5782 for (i = 0; i < hist_data->n_actions; i++) {
5783 struct action_data *action = hist_data->actions[i];
5784
5785 ret = hist_action_debug_show(m, action, i);
5786 if (ret)
5787 goto out;
5788 }
5789
5790 if (hist_data->n_save_vars)
5791 seq_puts(m, "\n save action variables (save() params):\n");
5792
5793 for (i = 0; i < hist_data->n_save_vars; i++) {
5794 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true);
5795 if (ret)
5796 goto out;
5797 }
5798 out:
5799 return ret;
5800 }
5801
5802 static void hist_trigger_debug_show(struct seq_file *m,
5803 struct event_trigger_data *data, int n)
5804 {
5805 struct hist_trigger_data *hist_data;
5806 int i, ret;
5807
5808 if (n > 0)
5809 seq_puts(m, "\n\n");
5810
5811 seq_puts(m, "# event histogram\n#\n# trigger info: ");
5812 data->ops->print(m, data);
5813 seq_puts(m, "#\n\n");
5814
5815 hist_data = data->private_data;
5816
5817 seq_printf(m, "hist_data: %p\n\n", hist_data);
5818 seq_printf(m, " n_vals: %u\n", hist_data->n_vals);
5819 seq_printf(m, " n_keys: %u\n", hist_data->n_keys);
5820 seq_printf(m, " n_fields: %u\n", hist_data->n_fields);
5821
5822 seq_puts(m, "\n val fields:\n\n");
5823
5824 seq_puts(m, " hist_data->fields[0]:\n");
5825 ret = hist_field_debug_show(m, hist_data->fields[0],
5826 HIST_FIELD_FL_HITCOUNT);
5827 if (ret)
5828 return;
5829
5830 for (i = 1; i < hist_data->n_vals; i++) {
5831 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5832 ret = hist_field_debug_show(m, hist_data->fields[i], 0);
5833 if (ret)
5834 return;
5835 }
5836
5837 seq_puts(m, "\n key fields:\n");
5838
5839 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) {
5840 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5841 ret = hist_field_debug_show(m, hist_data->fields[i],
5842 HIST_FIELD_FL_KEY);
5843 if (ret)
5844 return;
5845 }
5846
5847 if (hist_data->n_var_refs)
5848 seq_puts(m, "\n variable reference fields:\n");
5849
5850 for (i = 0; i < hist_data->n_var_refs; i++) {
5851 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i);
5852 ret = hist_field_debug_show(m, hist_data->var_refs[i],
5853 HIST_FIELD_FL_VAR_REF);
5854 if (ret)
5855 return;
5856 }
5857
5858 if (hist_data->n_field_vars)
5859 seq_puts(m, "\n field variables:\n");
5860
5861 for (i = 0; i < hist_data->n_field_vars; i++) {
5862 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false);
5863 if (ret)
5864 return;
5865 }
5866
5867 ret = hist_actions_debug_show(m, hist_data);
5868 if (ret)
5869 return;
5870 }
5871
5872 static int hist_debug_show(struct seq_file *m, void *v)
5873 {
5874 struct event_trigger_data *data;
5875 struct trace_event_file *event_file;
5876 int n = 0, ret = 0;
5877
5878 mutex_lock(&event_mutex);
5879
5880 event_file = event_file_file(m->private);
5881 if (unlikely(!event_file)) {
5882 ret = -ENODEV;
5883 goto out_unlock;
5884 }
5885
5886 list_for_each_entry(data, &event_file->triggers, list) {
5887 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5888 hist_trigger_debug_show(m, data, n++);
5889 }
5890
5891 out_unlock:
5892 mutex_unlock(&event_mutex);
5893
5894 return ret;
5895 }
5896
5897 static int event_hist_debug_open(struct inode *inode, struct file *file)
5898 {
5899 int ret;
5900
5901 ret = tracing_open_file_tr(inode, file);
5902 if (ret)
5903 return ret;
5904
5905 /* Clear private_data to avoid warning in single_open() */
5906 file->private_data = NULL;
5907 return single_open(file, hist_debug_show, file);
5908 }
5909
5910 const struct file_operations event_hist_debug_fops = {
5911 .open = event_hist_debug_open,
5912 .read = seq_read,
5913 .llseek = seq_lseek,
5914 .release = tracing_single_release_file_tr,
5915 };
5916 #endif
5917
5918 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
5919 {
5920 const char *field_name = hist_field_name(hist_field, 0);
5921
5922 if (hist_field->var.name)
5923 seq_printf(m, "%s=", hist_field->var.name);
5924
5925 if (hist_field->flags & HIST_FIELD_FL_CPU)
5926 seq_puts(m, "common_cpu");
5927 else if (hist_field->flags & HIST_FIELD_FL_CONST)
5928 seq_printf(m, "%llu", hist_field->constant);
5929 else if (field_name) {
5930 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
5931 hist_field->flags & HIST_FIELD_FL_ALIAS)
5932 seq_putc(m, '$');
5933 seq_printf(m, "%s", field_name);
5934 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
5935 seq_puts(m, "common_timestamp");
5936
5937 if (hist_field->flags) {
5938 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
5939 !(hist_field->flags & HIST_FIELD_FL_EXPR) &&
5940 !(hist_field->flags & HIST_FIELD_FL_STACKTRACE)) {
5941 const char *flags = get_hist_field_flags(hist_field);
5942
5943 if (flags)
5944 seq_printf(m, ".%s", flags);
5945 }
5946 }
5947 if (hist_field->buckets)
5948 seq_printf(m, "=%ld", hist_field->buckets);
5949 }
5950
5951 static int event_hist_trigger_print(struct seq_file *m,
5952 struct event_trigger_data *data)
5953 {
5954 struct hist_trigger_data *hist_data = data->private_data;
5955 struct hist_field *field;
5956 bool have_var = false;
5957 bool show_val = false;
5958 unsigned int i;
5959
5960 seq_puts(m, HIST_PREFIX);
5961
5962 if (data->name)
5963 seq_printf(m, "%s:", data->name);
5964
5965 seq_puts(m, "keys=");
5966
5967 for_each_hist_key_field(i, hist_data) {
5968 field = hist_data->fields[i];
5969
5970 if (i > hist_data->n_vals)
5971 seq_puts(m, ",");
5972
5973 if (field->flags & HIST_FIELD_FL_STACKTRACE) {
5974 if (field->field)
5975 seq_printf(m, "%s.stacktrace", field->field->name);
5976 else
5977 seq_puts(m, "common_stacktrace");
5978 } else
5979 hist_field_print(m, field);
5980 }
5981
5982 seq_puts(m, ":vals=");
5983
5984 for_each_hist_val_field(i, hist_data) {
5985 field = hist_data->fields[i];
5986 if (field->flags & HIST_FIELD_FL_VAR) {
5987 have_var = true;
5988 continue;
5989 }
5990
5991 if (i == HITCOUNT_IDX) {
5992 if (hist_data->attrs->no_hitcount)
5993 continue;
5994 seq_puts(m, "hitcount");
5995 } else {
5996 if (show_val)
5997 seq_puts(m, ",");
5998 hist_field_print(m, field);
5999 }
6000 show_val = true;
6001 }
6002
6003 if (have_var) {
6004 unsigned int n = 0;
6005
6006 seq_puts(m, ":");
6007
6008 for_each_hist_val_field(i, hist_data) {
6009 field = hist_data->fields[i];
6010
6011 if (field->flags & HIST_FIELD_FL_VAR) {
6012 if (n++)
6013 seq_puts(m, ",");
6014 hist_field_print(m, field);
6015 }
6016 }
6017 }
6018
6019 seq_puts(m, ":sort=");
6020
6021 for (i = 0; i < hist_data->n_sort_keys; i++) {
6022 struct tracing_map_sort_key *sort_key;
6023 unsigned int idx, first_key_idx;
6024
6025 /* skip VAR vals */
6026 first_key_idx = hist_data->n_vals - hist_data->n_vars;
6027
6028 sort_key = &hist_data->sort_keys[i];
6029 idx = sort_key->field_idx;
6030
6031 if (WARN_ON(idx >= HIST_FIELDS_MAX))
6032 return -EINVAL;
6033
6034 if (i > 0)
6035 seq_puts(m, ",");
6036
6037 if (idx == HITCOUNT_IDX)
6038 seq_puts(m, "hitcount");
6039 else {
6040 if (idx >= first_key_idx)
6041 idx += hist_data->n_vars;
6042 hist_field_print(m, hist_data->fields[idx]);
6043 }
6044
6045 if (sort_key->descending)
6046 seq_puts(m, ".descending");
6047 }
6048 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
6049 if (hist_data->enable_timestamps)
6050 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
6051 if (hist_data->attrs->no_hitcount)
6052 seq_puts(m, ":nohitcount");
6053
6054 print_actions_spec(m, hist_data);
6055
6056 if (data->filter_str)
6057 seq_printf(m, " if %s", data->filter_str);
6058
6059 if (data->paused)
6060 seq_puts(m, " [paused]");
6061 else
6062 seq_puts(m, " [active]");
6063
6064 seq_putc(m, '\n');
6065
6066 return 0;
6067 }
6068
6069 static int event_hist_trigger_init(struct event_trigger_data *data)
6070 {
6071 struct hist_trigger_data *hist_data = data->private_data;
6072
6073 if (!data->ref && hist_data->attrs->name)
6074 save_named_trigger(hist_data->attrs->name, data);
6075
6076 data->ref++;
6077
6078 return 0;
6079 }
6080
6081 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
6082 {
6083 struct trace_event_file *file;
6084 unsigned int i;
6085 char *cmd;
6086 int ret;
6087
6088 for (i = 0; i < hist_data->n_field_var_hists; i++) {
6089 file = hist_data->field_var_hists[i]->hist_data->event_file;
6090 cmd = hist_data->field_var_hists[i]->cmd;
6091 ret = event_hist_trigger_parse(&trigger_hist_cmd, file,
6092 "!hist", "hist", cmd);
6093 WARN_ON_ONCE(ret < 0);
6094 }
6095 }
6096
6097 static void event_hist_trigger_free(struct event_trigger_data *data)
6098 {
6099 struct hist_trigger_data *hist_data = data->private_data;
6100
6101 if (WARN_ON_ONCE(data->ref <= 0))
6102 return;
6103
6104 data->ref--;
6105 if (!data->ref) {
6106 if (data->name)
6107 del_named_trigger(data);
6108
6109 trigger_data_free(data);
6110
6111 remove_hist_vars(hist_data);
6112
6113 unregister_field_var_hists(hist_data);
6114
6115 destroy_hist_data(hist_data);
6116 }
6117 }
6118
6119 static struct event_trigger_ops event_hist_trigger_ops = {
6120 .trigger = event_hist_trigger,
6121 .print = event_hist_trigger_print,
6122 .init = event_hist_trigger_init,
6123 .free = event_hist_trigger_free,
6124 };
6125
6126 static int event_hist_trigger_named_init(struct event_trigger_data *data)
6127 {
6128 data->ref++;
6129
6130 save_named_trigger(data->named_data->name, data);
6131
6132 event_hist_trigger_init(data->named_data);
6133
6134 return 0;
6135 }
6136
6137 static void event_hist_trigger_named_free(struct event_trigger_data *data)
6138 {
6139 if (WARN_ON_ONCE(data->ref <= 0))
6140 return;
6141
6142 event_hist_trigger_free(data->named_data);
6143
6144 data->ref--;
6145 if (!data->ref) {
6146 del_named_trigger(data);
6147 trigger_data_free(data);
6148 }
6149 }
6150
6151 static struct event_trigger_ops event_hist_trigger_named_ops = {
6152 .trigger = event_hist_trigger,
6153 .print = event_hist_trigger_print,
6154 .init = event_hist_trigger_named_init,
6155 .free = event_hist_trigger_named_free,
6156 };
6157
6158 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
6159 char *param)
6160 {
6161 return &event_hist_trigger_ops;
6162 }
6163
6164 static void hist_clear(struct event_trigger_data *data)
6165 {
6166 struct hist_trigger_data *hist_data = data->private_data;
6167
6168 if (data->name)
6169 pause_named_trigger(data);
6170
6171 tracepoint_synchronize_unregister();
6172
6173 tracing_map_clear(hist_data->map);
6174
6175 if (data->name)
6176 unpause_named_trigger(data);
6177 }
6178
6179 static bool compatible_field(struct ftrace_event_field *field,
6180 struct ftrace_event_field *test_field)
6181 {
6182 if (field == test_field)
6183 return true;
6184 if (field == NULL || test_field == NULL)
6185 return false;
6186 if (strcmp(field->name, test_field->name) != 0)
6187 return false;
6188 if (strcmp(field->type, test_field->type) != 0)
6189 return false;
6190 if (field->size != test_field->size)
6191 return false;
6192 if (field->is_signed != test_field->is_signed)
6193 return false;
6194
6195 return true;
6196 }
6197
6198 static bool hist_trigger_match(struct event_trigger_data *data,
6199 struct event_trigger_data *data_test,
6200 struct event_trigger_data *named_data,
6201 bool ignore_filter)
6202 {
6203 struct tracing_map_sort_key *sort_key, *sort_key_test;
6204 struct hist_trigger_data *hist_data, *hist_data_test;
6205 struct hist_field *key_field, *key_field_test;
6206 unsigned int i;
6207
6208 if (named_data && (named_data != data_test) &&
6209 (named_data != data_test->named_data))
6210 return false;
6211
6212 if (!named_data && is_named_trigger(data_test))
6213 return false;
6214
6215 hist_data = data->private_data;
6216 hist_data_test = data_test->private_data;
6217
6218 if (hist_data->n_vals != hist_data_test->n_vals ||
6219 hist_data->n_fields != hist_data_test->n_fields ||
6220 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
6221 return false;
6222
6223 if (!ignore_filter) {
6224 if ((data->filter_str && !data_test->filter_str) ||
6225 (!data->filter_str && data_test->filter_str))
6226 return false;
6227 }
6228
6229 for_each_hist_field(i, hist_data) {
6230 key_field = hist_data->fields[i];
6231 key_field_test = hist_data_test->fields[i];
6232
6233 if (key_field->flags != key_field_test->flags)
6234 return false;
6235 if (!compatible_field(key_field->field, key_field_test->field))
6236 return false;
6237 if (key_field->offset != key_field_test->offset)
6238 return false;
6239 if (key_field->size != key_field_test->size)
6240 return false;
6241 if (key_field->is_signed != key_field_test->is_signed)
6242 return false;
6243 if (!!key_field->var.name != !!key_field_test->var.name)
6244 return false;
6245 if (key_field->var.name &&
6246 strcmp(key_field->var.name, key_field_test->var.name) != 0)
6247 return false;
6248 }
6249
6250 for (i = 0; i < hist_data->n_sort_keys; i++) {
6251 sort_key = &hist_data->sort_keys[i];
6252 sort_key_test = &hist_data_test->sort_keys[i];
6253
6254 if (sort_key->field_idx != sort_key_test->field_idx ||
6255 sort_key->descending != sort_key_test->descending)
6256 return false;
6257 }
6258
6259 if (!ignore_filter && data->filter_str &&
6260 (strcmp(data->filter_str, data_test->filter_str) != 0))
6261 return false;
6262
6263 if (!actions_match(hist_data, hist_data_test))
6264 return false;
6265
6266 return true;
6267 }
6268
6269 static bool existing_hist_update_only(char *glob,
6270 struct event_trigger_data *data,
6271 struct trace_event_file *file)
6272 {
6273 struct hist_trigger_data *hist_data = data->private_data;
6274 struct event_trigger_data *test, *named_data = NULL;
6275 bool updated = false;
6276
6277 if (!hist_data->attrs->pause && !hist_data->attrs->cont &&
6278 !hist_data->attrs->clear)
6279 goto out;
6280
6281 if (hist_data->attrs->name) {
6282 named_data = find_named_trigger(hist_data->attrs->name);
6283 if (named_data) {
6284 if (!hist_trigger_match(data, named_data, named_data,
6285 true))
6286 goto out;
6287 }
6288 }
6289
6290 if (hist_data->attrs->name && !named_data)
6291 goto out;
6292
6293 list_for_each_entry(test, &file->triggers, list) {
6294 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6295 if (!hist_trigger_match(data, test, named_data, false))
6296 continue;
6297 if (hist_data->attrs->pause)
6298 test->paused = true;
6299 else if (hist_data->attrs->cont)
6300 test->paused = false;
6301 else if (hist_data->attrs->clear)
6302 hist_clear(test);
6303 updated = true;
6304 goto out;
6305 }
6306 }
6307 out:
6308 return updated;
6309 }
6310
6311 static int hist_register_trigger(char *glob,
6312 struct event_trigger_data *data,
6313 struct trace_event_file *file)
6314 {
6315 struct hist_trigger_data *hist_data = data->private_data;
6316 struct event_trigger_data *test, *named_data = NULL;
6317 struct trace_array *tr = file->tr;
6318 int ret = 0;
6319
6320 if (hist_data->attrs->name) {
6321 named_data = find_named_trigger(hist_data->attrs->name);
6322 if (named_data) {
6323 if (!hist_trigger_match(data, named_data, named_data,
6324 true)) {
6325 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name));
6326 ret = -EINVAL;
6327 goto out;
6328 }
6329 }
6330 }
6331
6332 if (hist_data->attrs->name && !named_data)
6333 goto new;
6334
6335 lockdep_assert_held(&event_mutex);
6336
6337 list_for_each_entry(test, &file->triggers, list) {
6338 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6339 if (hist_trigger_match(data, test, named_data, false)) {
6340 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0);
6341 ret = -EEXIST;
6342 goto out;
6343 }
6344 }
6345 }
6346 new:
6347 if (hist_data->attrs->cont || hist_data->attrs->clear) {
6348 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0);
6349 ret = -ENOENT;
6350 goto out;
6351 }
6352
6353 if (hist_data->attrs->pause)
6354 data->paused = true;
6355
6356 if (named_data) {
6357 data->private_data = named_data->private_data;
6358 set_named_trigger_data(data, named_data);
6359 data->ops = &event_hist_trigger_named_ops;
6360 }
6361
6362 if (data->ops->init) {
6363 ret = data->ops->init(data);
6364 if (ret < 0)
6365 goto out;
6366 }
6367
6368 if (hist_data->enable_timestamps) {
6369 char *clock = hist_data->attrs->clock;
6370
6371 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
6372 if (ret) {
6373 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock));
6374 goto out;
6375 }
6376
6377 tracing_set_filter_buffering(file->tr, true);
6378 }
6379
6380 if (named_data)
6381 destroy_hist_data(hist_data);
6382 out:
6383 return ret;
6384 }
6385
6386 static int hist_trigger_enable(struct event_trigger_data *data,
6387 struct trace_event_file *file)
6388 {
6389 int ret = 0;
6390
6391 list_add_tail_rcu(&data->list, &file->triggers);
6392
6393 update_cond_flag(file);
6394
6395 if (trace_event_trigger_enable_disable(file, 1) < 0) {
6396 list_del_rcu(&data->list);
6397 update_cond_flag(file);
6398 ret--;
6399 }
6400
6401 return ret;
6402 }
6403
6404 static bool have_hist_trigger_match(struct event_trigger_data *data,
6405 struct trace_event_file *file)
6406 {
6407 struct hist_trigger_data *hist_data = data->private_data;
6408 struct event_trigger_data *test, *named_data = NULL;
6409 bool match = false;
6410
6411 lockdep_assert_held(&event_mutex);
6412
6413 if (hist_data->attrs->name)
6414 named_data = find_named_trigger(hist_data->attrs->name);
6415
6416 list_for_each_entry(test, &file->triggers, list) {
6417 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6418 if (hist_trigger_match(data, test, named_data, false)) {
6419 match = true;
6420 break;
6421 }
6422 }
6423 }
6424
6425 return match;
6426 }
6427
6428 static bool hist_trigger_check_refs(struct event_trigger_data *data,
6429 struct trace_event_file *file)
6430 {
6431 struct hist_trigger_data *hist_data = data->private_data;
6432 struct event_trigger_data *test, *named_data = NULL;
6433
6434 lockdep_assert_held(&event_mutex);
6435
6436 if (hist_data->attrs->name)
6437 named_data = find_named_trigger(hist_data->attrs->name);
6438
6439 list_for_each_entry(test, &file->triggers, list) {
6440 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6441 if (!hist_trigger_match(data, test, named_data, false))
6442 continue;
6443 hist_data = test->private_data;
6444 if (check_var_refs(hist_data))
6445 return true;
6446 break;
6447 }
6448 }
6449
6450 return false;
6451 }
6452
6453 static void hist_unregister_trigger(char *glob,
6454 struct event_trigger_data *data,
6455 struct trace_event_file *file)
6456 {
6457 struct event_trigger_data *test = NULL, *iter, *named_data = NULL;
6458 struct hist_trigger_data *hist_data = data->private_data;
6459
6460 lockdep_assert_held(&event_mutex);
6461
6462 if (hist_data->attrs->name)
6463 named_data = find_named_trigger(hist_data->attrs->name);
6464
6465 list_for_each_entry(iter, &file->triggers, list) {
6466 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6467 if (!hist_trigger_match(data, iter, named_data, false))
6468 continue;
6469 test = iter;
6470 list_del_rcu(&test->list);
6471 trace_event_trigger_enable_disable(file, 0);
6472 update_cond_flag(file);
6473 break;
6474 }
6475 }
6476
6477 if (test && test->ops->free)
6478 test->ops->free(test);
6479
6480 if (hist_data->enable_timestamps) {
6481 if (!hist_data->remove || test)
6482 tracing_set_filter_buffering(file->tr, false);
6483 }
6484 }
6485
6486 static bool hist_file_check_refs(struct trace_event_file *file)
6487 {
6488 struct hist_trigger_data *hist_data;
6489 struct event_trigger_data *test;
6490
6491 lockdep_assert_held(&event_mutex);
6492
6493 list_for_each_entry(test, &file->triggers, list) {
6494 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6495 hist_data = test->private_data;
6496 if (check_var_refs(hist_data))
6497 return true;
6498 }
6499 }
6500
6501 return false;
6502 }
6503
6504 static void hist_unreg_all(struct trace_event_file *file)
6505 {
6506 struct event_trigger_data *test, *n;
6507 struct hist_trigger_data *hist_data;
6508 struct synth_event *se;
6509 const char *se_name;
6510
6511 lockdep_assert_held(&event_mutex);
6512
6513 if (hist_file_check_refs(file))
6514 return;
6515
6516 list_for_each_entry_safe(test, n, &file->triggers, list) {
6517 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6518 hist_data = test->private_data;
6519 list_del_rcu(&test->list);
6520 trace_event_trigger_enable_disable(file, 0);
6521
6522 se_name = trace_event_name(file->event_call);
6523 se = find_synth_event(se_name);
6524 if (se)
6525 se->ref--;
6526
6527 update_cond_flag(file);
6528 if (hist_data->enable_timestamps)
6529 tracing_set_filter_buffering(file->tr, false);
6530 if (test->ops->free)
6531 test->ops->free(test);
6532 }
6533 }
6534 }
6535
6536 static int event_hist_trigger_parse(struct event_command *cmd_ops,
6537 struct trace_event_file *file,
6538 char *glob, char *cmd,
6539 char *param_and_filter)
6540 {
6541 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
6542 struct event_trigger_data *trigger_data;
6543 struct hist_trigger_attrs *attrs;
6544 struct hist_trigger_data *hist_data;
6545 char *param, *filter, *p, *start;
6546 struct synth_event *se;
6547 const char *se_name;
6548 bool remove;
6549 int ret = 0;
6550
6551 lockdep_assert_held(&event_mutex);
6552
6553 if (WARN_ON(!glob))
6554 return -EINVAL;
6555
6556 if (glob[0]) {
6557 hist_err_clear();
6558 last_cmd_set(file, param_and_filter);
6559 }
6560
6561 remove = event_trigger_check_remove(glob);
6562
6563 if (event_trigger_empty_param(param_and_filter))
6564 return -EINVAL;
6565
6566 /*
6567 * separate the trigger from the filter (k:v [if filter])
6568 * allowing for whitespace in the trigger
6569 */
6570 p = param = param_and_filter;
6571 do {
6572 p = strstr(p, "if");
6573 if (!p)
6574 break;
6575 if (p == param_and_filter)
6576 return -EINVAL;
6577 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
6578 p++;
6579 continue;
6580 }
6581 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1)
6582 return -EINVAL;
6583 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
6584 p++;
6585 continue;
6586 }
6587 break;
6588 } while (1);
6589
6590 if (!p)
6591 filter = NULL;
6592 else {
6593 *(p - 1) = '\0';
6594 filter = strstrip(p);
6595 param = strstrip(param);
6596 }
6597
6598 /*
6599 * To simplify arithmetic expression parsing, replace occurrences of
6600 * '.sym-offset' modifier with '.symXoffset'
6601 */
6602 start = strstr(param, ".sym-offset");
6603 while (start) {
6604 *(start + 4) = 'X';
6605 start = strstr(start + 11, ".sym-offset");
6606 }
6607
6608 attrs = parse_hist_trigger_attrs(file->tr, param);
6609 if (IS_ERR(attrs))
6610 return PTR_ERR(attrs);
6611
6612 if (attrs->map_bits)
6613 hist_trigger_bits = attrs->map_bits;
6614
6615 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
6616 if (IS_ERR(hist_data)) {
6617 destroy_hist_trigger_attrs(attrs);
6618 return PTR_ERR(hist_data);
6619 }
6620
6621 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data);
6622 if (!trigger_data) {
6623 ret = -ENOMEM;
6624 goto out_free;
6625 }
6626
6627 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
6628 if (ret < 0)
6629 goto out_free;
6630
6631 if (remove) {
6632 if (!have_hist_trigger_match(trigger_data, file))
6633 goto out_free;
6634
6635 if (hist_trigger_check_refs(trigger_data, file)) {
6636 ret = -EBUSY;
6637 goto out_free;
6638 }
6639
6640 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
6641 se_name = trace_event_name(file->event_call);
6642 se = find_synth_event(se_name);
6643 if (se)
6644 se->ref--;
6645 ret = 0;
6646 goto out_free;
6647 }
6648
6649 if (existing_hist_update_only(glob, trigger_data, file))
6650 goto out_free;
6651
6652 ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
6653 if (ret < 0)
6654 goto out_free;
6655
6656 if (get_named_trigger_data(trigger_data))
6657 goto enable;
6658
6659 ret = create_actions(hist_data);
6660 if (ret)
6661 goto out_unreg;
6662
6663 if (has_hist_vars(hist_data) || hist_data->n_var_refs) {
6664 ret = save_hist_vars(hist_data);
6665 if (ret)
6666 goto out_unreg;
6667 }
6668
6669 ret = tracing_map_init(hist_data->map);
6670 if (ret)
6671 goto out_unreg;
6672 enable:
6673 ret = hist_trigger_enable(trigger_data, file);
6674 if (ret)
6675 goto out_unreg;
6676
6677 se_name = trace_event_name(file->event_call);
6678 se = find_synth_event(se_name);
6679 if (se)
6680 se->ref++;
6681 out:
6682 if (ret == 0 && glob[0])
6683 hist_err_clear();
6684
6685 return ret;
6686 out_unreg:
6687 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
6688 out_free:
6689 event_trigger_reset_filter(cmd_ops, trigger_data);
6690
6691 remove_hist_vars(hist_data);
6692
6693 kfree(trigger_data);
6694
6695 destroy_hist_data(hist_data);
6696 goto out;
6697 }
6698
6699 static struct event_command trigger_hist_cmd = {
6700 .name = "hist",
6701 .trigger_type = ETT_EVENT_HIST,
6702 .flags = EVENT_CMD_FL_NEEDS_REC,
6703 .parse = event_hist_trigger_parse,
6704 .reg = hist_register_trigger,
6705 .unreg = hist_unregister_trigger,
6706 .unreg_all = hist_unreg_all,
6707 .get_trigger_ops = event_hist_get_trigger_ops,
6708 .set_filter = set_trigger_filter,
6709 };
6710
6711 __init int register_trigger_hist_cmd(void)
6712 {
6713 int ret;
6714
6715 ret = register_event_command(&trigger_hist_cmd);
6716 WARN_ON(ret < 0);
6717
6718 return ret;
6719 }
6720
6721 static void
6722 hist_enable_trigger(struct event_trigger_data *data,
6723 struct trace_buffer *buffer, void *rec,
6724 struct ring_buffer_event *event)
6725 {
6726 struct enable_trigger_data *enable_data = data->private_data;
6727 struct event_trigger_data *test;
6728
6729 list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
6730 lockdep_is_held(&event_mutex)) {
6731 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6732 if (enable_data->enable)
6733 test->paused = false;
6734 else
6735 test->paused = true;
6736 }
6737 }
6738 }
6739
6740 static void
6741 hist_enable_count_trigger(struct event_trigger_data *data,
6742 struct trace_buffer *buffer, void *rec,
6743 struct ring_buffer_event *event)
6744 {
6745 if (!data->count)
6746 return;
6747
6748 if (data->count != -1)
6749 (data->count)--;
6750
6751 hist_enable_trigger(data, buffer, rec, event);
6752 }
6753
6754 static struct event_trigger_ops hist_enable_trigger_ops = {
6755 .trigger = hist_enable_trigger,
6756 .print = event_enable_trigger_print,
6757 .init = event_trigger_init,
6758 .free = event_enable_trigger_free,
6759 };
6760
6761 static struct event_trigger_ops hist_enable_count_trigger_ops = {
6762 .trigger = hist_enable_count_trigger,
6763 .print = event_enable_trigger_print,
6764 .init = event_trigger_init,
6765 .free = event_enable_trigger_free,
6766 };
6767
6768 static struct event_trigger_ops hist_disable_trigger_ops = {
6769 .trigger = hist_enable_trigger,
6770 .print = event_enable_trigger_print,
6771 .init = event_trigger_init,
6772 .free = event_enable_trigger_free,
6773 };
6774
6775 static struct event_trigger_ops hist_disable_count_trigger_ops = {
6776 .trigger = hist_enable_count_trigger,
6777 .print = event_enable_trigger_print,
6778 .init = event_trigger_init,
6779 .free = event_enable_trigger_free,
6780 };
6781
6782 static struct event_trigger_ops *
6783 hist_enable_get_trigger_ops(char *cmd, char *param)
6784 {
6785 struct event_trigger_ops *ops;
6786 bool enable;
6787
6788 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
6789
6790 if (enable)
6791 ops = param ? &hist_enable_count_trigger_ops :
6792 &hist_enable_trigger_ops;
6793 else
6794 ops = param ? &hist_disable_count_trigger_ops :
6795 &hist_disable_trigger_ops;
6796
6797 return ops;
6798 }
6799
6800 static void hist_enable_unreg_all(struct trace_event_file *file)
6801 {
6802 struct event_trigger_data *test, *n;
6803
6804 list_for_each_entry_safe(test, n, &file->triggers, list) {
6805 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
6806 list_del_rcu(&test->list);
6807 update_cond_flag(file);
6808 trace_event_trigger_enable_disable(file, 0);
6809 if (test->ops->free)
6810 test->ops->free(test);
6811 }
6812 }
6813 }
6814
6815 static struct event_command trigger_hist_enable_cmd = {
6816 .name = ENABLE_HIST_STR,
6817 .trigger_type = ETT_HIST_ENABLE,
6818 .parse = event_enable_trigger_parse,
6819 .reg = event_enable_register_trigger,
6820 .unreg = event_enable_unregister_trigger,
6821 .unreg_all = hist_enable_unreg_all,
6822 .get_trigger_ops = hist_enable_get_trigger_ops,
6823 .set_filter = set_trigger_filter,
6824 };
6825
6826 static struct event_command trigger_hist_disable_cmd = {
6827 .name = DISABLE_HIST_STR,
6828 .trigger_type = ETT_HIST_ENABLE,
6829 .parse = event_enable_trigger_parse,
6830 .reg = event_enable_register_trigger,
6831 .unreg = event_enable_unregister_trigger,
6832 .unreg_all = hist_enable_unreg_all,
6833 .get_trigger_ops = hist_enable_get_trigger_ops,
6834 .set_filter = set_trigger_filter,
6835 };
6836
6837 static __init void unregister_trigger_hist_enable_disable_cmds(void)
6838 {
6839 unregister_event_command(&trigger_hist_enable_cmd);
6840 unregister_event_command(&trigger_hist_disable_cmd);
6841 }
6842
6843 __init int register_trigger_hist_enable_disable_cmds(void)
6844 {
6845 int ret;
6846
6847 ret = register_event_command(&trigger_hist_enable_cmd);
6848 if (WARN_ON(ret < 0))
6849 return ret;
6850 ret = register_event_command(&trigger_hist_disable_cmd);
6851 if (WARN_ON(ret < 0))
6852 unregister_trigger_hist_enable_disable_cmds();
6853
6854 return ret;
6855 }
Kernel DRM miscellaneous fixes and cross-tree changes