1 /* SPDX-License-Identifier: GPL-2.0 */
2
3 #ifndef _LINUX_TRACE_EVENT_H
4 #define _LINUX_TRACE_EVENT_H
5
6 #include <linux/ring_buffer.h>
7 #include <linux/trace_seq.h>
8 #include <linux/percpu.h>
9 #include <linux/hardirq.h>
10 #include <linux/perf_event.h>
11 #include <linux/tracepoint.h>
12
13 struct trace_array;
14 struct array_buffer;
15 struct tracer;
16 struct dentry;
17 struct bpf_prog;
18 union bpf_attr;
19
20 /* Used for event string fields when they are NULL */
21 #define EVENT_NULL_STR "(null)"
22
23 const char *trace_print_flags_seq(struct trace_seq *p, const char *delim,
24 unsigned long flags,
25 const struct trace_print_flags *flag_array);
26
27 const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
28 const struct trace_print_flags *symbol_array);
29
30 #if BITS_PER_LONG == 32
31 const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
32 unsigned long long flags,
33 const struct trace_print_flags_u64 *flag_array);
34
35 const char *trace_print_symbols_seq_u64(struct trace_seq *p,
36 unsigned long long val,
37 const struct trace_print_flags_u64
38 *symbol_array);
39 #endif
40
41 const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
42 unsigned int bitmask_size);
43
44 const char *trace_print_hex_seq(struct trace_seq *p,
45 const unsigned char *buf, int len,
46 bool concatenate);
47
48 const char *trace_print_array_seq(struct trace_seq *p,
49 const void *buf, int count,
50 size_t el_size);
51
52 const char *
53 trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
54 int prefix_type, int rowsize, int groupsize,
55 const void *buf, size_t len, bool ascii);
56
57 struct trace_iterator;
58 struct trace_event;
59
60 int trace_raw_output_prep(struct trace_iterator *iter,
61 struct trace_event *event);
62 extern __printf(2, 3)
63 void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...);
64
65 /* Used to find the offset and length of dynamic fields in trace events */
66 struct trace_dynamic_info {
67 #ifdef CONFIG_CPU_BIG_ENDIAN
68 u16 len;
69 u16 offset;
70 #else
71 u16 offset;
72 u16 len;
73 #endif
74 } __packed;
75
76 /*
77 * The trace entry - the most basic unit of tracing. This is what
78 * is printed in the end as a single line in the trace output, such as:
79 *
80 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
81 */
82 struct trace_entry {
83 unsigned short type;
84 unsigned char flags;
85 unsigned char preempt_count;
86 int pid;
87 };
88
89 #define TRACE_EVENT_TYPE_MAX \
90 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
91
92 /*
93 * Trace iterator - used by printout routines who present trace
94 * results to users and which routines might sleep, etc:
95 */
96 struct trace_iterator {
97 struct trace_array *tr;
98 struct tracer *trace;
99 struct array_buffer *array_buffer;
100 void *private;
101 int cpu_file;
102 struct mutex mutex;
103 struct ring_buffer_iter **buffer_iter;
104 unsigned long iter_flags;
105 void *temp; /* temp holder */
106 unsigned int temp_size;
107 char *fmt; /* modified format holder */
108 unsigned int fmt_size;
109 atomic_t wait_index;
110
111 /* trace_seq for __print_flags() and __print_symbolic() etc. */
112 struct trace_seq tmp_seq;
113
114 cpumask_var_t started;
115
116 /* Set when the file is closed to prevent new waiters */
117 bool closed;
118
119 /* it's true when current open file is snapshot */
120 bool snapshot;
121
122 /* The below is zeroed out in pipe_read */
123 struct trace_seq seq;
124 struct trace_entry *ent;
125 unsigned long lost_events;
126 int leftover;
127 int ent_size;
128 int cpu;
129 u64 ts;
130
131 loff_t pos;
132 long idx;
133
134 /* All new field here will be zeroed out in pipe_read */
135 };
136
137 enum trace_iter_flags {
138 TRACE_FILE_LAT_FMT = 1,
139 TRACE_FILE_ANNOTATE = 2,
140 TRACE_FILE_TIME_IN_NS = 4,
141 };
142
143
144 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
145 int flags, struct trace_event *event);
146
147 struct trace_event_functions {
148 trace_print_func trace;
149 trace_print_func raw;
150 trace_print_func hex;
151 trace_print_func binary;
152 };
153
154 struct trace_event {
155 struct hlist_node node;
156 int type;
157 struct trace_event_functions *funcs;
158 };
159
160 extern int register_trace_event(struct trace_event *event);
161 extern int unregister_trace_event(struct trace_event *event);
162
163 /* Return values for print_line callback */
164 enum print_line_t {
165 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
166 TRACE_TYPE_HANDLED = 1,
167 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */
168 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */
169 };
170
171 enum print_line_t trace_handle_return(struct trace_seq *s);
172
tracing_generic_entry_update(struct trace_entry * entry,unsigned short type,unsigned int trace_ctx)173 static inline void tracing_generic_entry_update(struct trace_entry *entry,
174 unsigned short type,
175 unsigned int trace_ctx)
176 {
177 entry->preempt_count = trace_ctx & 0xff;
178 entry->pid = current->pid;
179 entry->type = type;
180 entry->flags = trace_ctx >> 16;
181 }
182
183 unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
184
185 enum trace_flag_type {
186 TRACE_FLAG_IRQS_OFF = 0x01,
187 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
188 TRACE_FLAG_NEED_RESCHED = 0x04,
189 TRACE_FLAG_HARDIRQ = 0x08,
190 TRACE_FLAG_SOFTIRQ = 0x10,
191 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
192 TRACE_FLAG_NMI = 0x40,
193 TRACE_FLAG_BH_OFF = 0x80,
194 };
195
196 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
tracing_gen_ctx_flags(unsigned long irqflags)197 static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
198 {
199 unsigned int irq_status = irqs_disabled_flags(irqflags) ?
200 TRACE_FLAG_IRQS_OFF : 0;
201 return tracing_gen_ctx_irq_test(irq_status);
202 }
tracing_gen_ctx(void)203 static inline unsigned int tracing_gen_ctx(void)
204 {
205 unsigned long irqflags;
206
207 local_save_flags(irqflags);
208 return tracing_gen_ctx_flags(irqflags);
209 }
210 #else
211
tracing_gen_ctx_flags(unsigned long irqflags)212 static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
213 {
214 return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
215 }
tracing_gen_ctx(void)216 static inline unsigned int tracing_gen_ctx(void)
217 {
218 return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
219 }
220 #endif
221
tracing_gen_ctx_dec(void)222 static inline unsigned int tracing_gen_ctx_dec(void)
223 {
224 unsigned int trace_ctx;
225
226 trace_ctx = tracing_gen_ctx();
227 /*
228 * Subtract one from the preemption counter if preemption is enabled,
229 * see trace_event_buffer_reserve()for details.
230 */
231 if (IS_ENABLED(CONFIG_PREEMPTION))
232 trace_ctx--;
233 return trace_ctx;
234 }
235
236 struct trace_event_file;
237
238 struct ring_buffer_event *
239 trace_event_buffer_lock_reserve(struct trace_buffer **current_buffer,
240 struct trace_event_file *trace_file,
241 int type, unsigned long len,
242 unsigned int trace_ctx);
243
244 #define TRACE_RECORD_CMDLINE BIT(0)
245 #define TRACE_RECORD_TGID BIT(1)
246
247 void tracing_record_taskinfo(struct task_struct *task, int flags);
248 void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
249 struct task_struct *next, int flags);
250
251 void tracing_record_cmdline(struct task_struct *task);
252 void tracing_record_tgid(struct task_struct *task);
253
254 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
255 __printf(3, 4);
256
257 struct event_filter;
258
259 enum trace_reg {
260 TRACE_REG_REGISTER,
261 TRACE_REG_UNREGISTER,
262 #ifdef CONFIG_PERF_EVENTS
263 TRACE_REG_PERF_REGISTER,
264 TRACE_REG_PERF_UNREGISTER,
265 TRACE_REG_PERF_OPEN,
266 TRACE_REG_PERF_CLOSE,
267 /*
268 * These (ADD/DEL) use a 'boolean' return value, where 1 (true) means a
269 * custom action was taken and the default action is not to be
270 * performed.
271 */
272 TRACE_REG_PERF_ADD,
273 TRACE_REG_PERF_DEL,
274 #endif
275 };
276
277 struct trace_event_call;
278
279 #define TRACE_FUNCTION_TYPE ((const char *)~0UL)
280
281 struct trace_event_fields {
282 const char *type;
283 union {
284 struct {
285 const char *name;
286 const int size;
287 const int align;
288 const int is_signed;
289 const int filter_type;
290 const int len;
291 };
292 int (*define_fields)(struct trace_event_call *);
293 };
294 };
295
296 struct trace_event_class {
297 const char *system;
298 void *probe;
299 #ifdef CONFIG_PERF_EVENTS
300 void *perf_probe;
301 #endif
302 int (*reg)(struct trace_event_call *event,
303 enum trace_reg type, void *data);
304 struct trace_event_fields *fields_array;
305 struct list_head *(*get_fields)(struct trace_event_call *);
306 struct list_head fields;
307 int (*raw_init)(struct trace_event_call *);
308 };
309
310 extern int trace_event_reg(struct trace_event_call *event,
311 enum trace_reg type, void *data);
312
313 struct trace_event_buffer {
314 struct trace_buffer *buffer;
315 struct ring_buffer_event *event;
316 struct trace_event_file *trace_file;
317 void *entry;
318 unsigned int trace_ctx;
319 struct pt_regs *regs;
320 };
321
322 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
323 struct trace_event_file *trace_file,
324 unsigned long len);
325
326 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);
327
328 enum {
329 TRACE_EVENT_FL_FILTERED_BIT,
330 TRACE_EVENT_FL_CAP_ANY_BIT,
331 TRACE_EVENT_FL_NO_SET_FILTER_BIT,
332 TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
333 TRACE_EVENT_FL_TRACEPOINT_BIT,
334 TRACE_EVENT_FL_DYNAMIC_BIT,
335 TRACE_EVENT_FL_KPROBE_BIT,
336 TRACE_EVENT_FL_UPROBE_BIT,
337 TRACE_EVENT_FL_EPROBE_BIT,
338 TRACE_EVENT_FL_FPROBE_BIT,
339 TRACE_EVENT_FL_CUSTOM_BIT,
340 };
341
342 /*
343 * Event flags:
344 * FILTERED - The event has a filter attached
345 * CAP_ANY - Any user can enable for perf
346 * NO_SET_FILTER - Set when filter has error and is to be ignored
347 * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
348 * TRACEPOINT - Event is a tracepoint
349 * DYNAMIC - Event is a dynamic event (created at run time)
350 * KPROBE - Event is a kprobe
351 * UPROBE - Event is a uprobe
352 * EPROBE - Event is an event probe
353 * FPROBE - Event is an function probe
354 * CUSTOM - Event is a custom event (to be attached to an exsiting tracepoint)
355 * This is set when the custom event has not been attached
356 * to a tracepoint yet, then it is cleared when it is.
357 */
358 enum {
359 TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
360 TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
361 TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
362 TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
363 TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
364 TRACE_EVENT_FL_DYNAMIC = (1 << TRACE_EVENT_FL_DYNAMIC_BIT),
365 TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT),
366 TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT),
367 TRACE_EVENT_FL_EPROBE = (1 << TRACE_EVENT_FL_EPROBE_BIT),
368 TRACE_EVENT_FL_FPROBE = (1 << TRACE_EVENT_FL_FPROBE_BIT),
369 TRACE_EVENT_FL_CUSTOM = (1 << TRACE_EVENT_FL_CUSTOM_BIT),
370 };
371
372 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
373
374 struct trace_event_call {
375 struct list_head list;
376 struct trace_event_class *class;
377 union {
378 char *name;
379 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
380 struct tracepoint *tp;
381 };
382 struct trace_event event;
383 char *print_fmt;
384 struct event_filter *filter;
385 /*
386 * Static events can disappear with modules,
387 * where as dynamic ones need their own ref count.
388 */
389 union {
390 void *module;
391 atomic_t refcnt;
392 };
393 void *data;
394
395 /* See the TRACE_EVENT_FL_* flags above */
396 int flags; /* static flags of different events */
397
398 #ifdef CONFIG_PERF_EVENTS
399 int perf_refcount;
400 struct hlist_head __percpu *perf_events;
401 struct bpf_prog_array __rcu *prog_array;
402
403 int (*perf_perm)(struct trace_event_call *,
404 struct perf_event *);
405 #endif
406 };
407
408 #ifdef CONFIG_DYNAMIC_EVENTS
409 bool trace_event_dyn_try_get_ref(struct trace_event_call *call);
410 void trace_event_dyn_put_ref(struct trace_event_call *call);
411 bool trace_event_dyn_busy(struct trace_event_call *call);
412 #else
trace_event_dyn_try_get_ref(struct trace_event_call * call)413 static inline bool trace_event_dyn_try_get_ref(struct trace_event_call *call)
414 {
415 /* Without DYNAMIC_EVENTS configured, nothing should be calling this */
416 return false;
417 }
trace_event_dyn_put_ref(struct trace_event_call * call)418 static inline void trace_event_dyn_put_ref(struct trace_event_call *call)
419 {
420 }
trace_event_dyn_busy(struct trace_event_call * call)421 static inline bool trace_event_dyn_busy(struct trace_event_call *call)
422 {
423 /* Nothing should call this without DYNAIMIC_EVENTS configured. */
424 return true;
425 }
426 #endif
427
trace_event_try_get_ref(struct trace_event_call * call)428 static inline bool trace_event_try_get_ref(struct trace_event_call *call)
429 {
430 if (call->flags & TRACE_EVENT_FL_DYNAMIC)
431 return trace_event_dyn_try_get_ref(call);
432 else
433 return try_module_get(call->module);
434 }
435
trace_event_put_ref(struct trace_event_call * call)436 static inline void trace_event_put_ref(struct trace_event_call *call)
437 {
438 if (call->flags & TRACE_EVENT_FL_DYNAMIC)
439 trace_event_dyn_put_ref(call);
440 else
441 module_put(call->module);
442 }
443
444 #ifdef CONFIG_PERF_EVENTS
bpf_prog_array_valid(struct trace_event_call * call)445 static inline bool bpf_prog_array_valid(struct trace_event_call *call)
446 {
447 /*
448 * This inline function checks whether call->prog_array
449 * is valid or not. The function is called in various places,
450 * outside rcu_read_lock/unlock, as a heuristic to speed up execution.
451 *
452 * If this function returns true, and later call->prog_array
453 * becomes false inside rcu_read_lock/unlock region,
454 * we bail out then. If this function return false,
455 * there is a risk that we might miss a few events if the checking
456 * were delayed until inside rcu_read_lock/unlock region and
457 * call->prog_array happened to become non-NULL then.
458 *
459 * Here, READ_ONCE() is used instead of rcu_access_pointer().
460 * rcu_access_pointer() requires the actual definition of
461 * "struct bpf_prog_array" while READ_ONCE() only needs
462 * a declaration of the same type.
463 */
464 return !!READ_ONCE(call->prog_array);
465 }
466 #endif
467
468 static inline const char *
trace_event_name(struct trace_event_call * call)469 trace_event_name(struct trace_event_call *call)
470 {
471 if (call->flags & TRACE_EVENT_FL_CUSTOM)
472 return call->name;
473 else if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
474 return call->tp ? call->tp->name : NULL;
475 else
476 return call->name;
477 }
478
479 static inline struct list_head *
trace_get_fields(struct trace_event_call * event_call)480 trace_get_fields(struct trace_event_call *event_call)
481 {
482 if (!event_call->class->get_fields)
483 return &event_call->class->fields;
484 return event_call->class->get_fields(event_call);
485 }
486
487 struct trace_subsystem_dir;
488
489 enum {
490 EVENT_FILE_FL_ENABLED_BIT,
491 EVENT_FILE_FL_RECORDED_CMD_BIT,
492 EVENT_FILE_FL_RECORDED_TGID_BIT,
493 EVENT_FILE_FL_FILTERED_BIT,
494 EVENT_FILE_FL_NO_SET_FILTER_BIT,
495 EVENT_FILE_FL_SOFT_MODE_BIT,
496 EVENT_FILE_FL_SOFT_DISABLED_BIT,
497 EVENT_FILE_FL_TRIGGER_MODE_BIT,
498 EVENT_FILE_FL_TRIGGER_COND_BIT,
499 EVENT_FILE_FL_PID_FILTER_BIT,
500 EVENT_FILE_FL_WAS_ENABLED_BIT,
501 EVENT_FILE_FL_FREED_BIT,
502 };
503
504 extern struct trace_event_file *trace_get_event_file(const char *instance,
505 const char *system,
506 const char *event);
507 extern void trace_put_event_file(struct trace_event_file *file);
508
509 #define MAX_DYNEVENT_CMD_LEN (2048)
510
511 enum dynevent_type {
512 DYNEVENT_TYPE_SYNTH = 1,
513 DYNEVENT_TYPE_KPROBE,
514 DYNEVENT_TYPE_NONE,
515 };
516
517 struct dynevent_cmd;
518
519 typedef int (*dynevent_create_fn_t)(struct dynevent_cmd *cmd);
520
521 struct dynevent_cmd {
522 struct seq_buf seq;
523 const char *event_name;
524 unsigned int n_fields;
525 enum dynevent_type type;
526 dynevent_create_fn_t run_command;
527 void *private_data;
528 };
529
530 extern int dynevent_create(struct dynevent_cmd *cmd);
531
532 extern int synth_event_delete(const char *name);
533
534 extern void synth_event_cmd_init(struct dynevent_cmd *cmd,
535 char *buf, int maxlen);
536
537 extern int __synth_event_gen_cmd_start(struct dynevent_cmd *cmd,
538 const char *name,
539 struct module *mod, ...);
540
541 #define synth_event_gen_cmd_start(cmd, name, mod, ...) \
542 __synth_event_gen_cmd_start(cmd, name, mod, ## __VA_ARGS__, NULL)
543
544 struct synth_field_desc {
545 const char *type;
546 const char *name;
547 };
548
549 extern int synth_event_gen_cmd_array_start(struct dynevent_cmd *cmd,
550 const char *name,
551 struct module *mod,
552 struct synth_field_desc *fields,
553 unsigned int n_fields);
554 extern int synth_event_create(const char *name,
555 struct synth_field_desc *fields,
556 unsigned int n_fields, struct module *mod);
557
558 extern int synth_event_add_field(struct dynevent_cmd *cmd,
559 const char *type,
560 const char *name);
561 extern int synth_event_add_field_str(struct dynevent_cmd *cmd,
562 const char *type_name);
563 extern int synth_event_add_fields(struct dynevent_cmd *cmd,
564 struct synth_field_desc *fields,
565 unsigned int n_fields);
566
567 #define synth_event_gen_cmd_end(cmd) \
568 dynevent_create(cmd)
569
570 struct synth_event;
571
572 struct synth_event_trace_state {
573 struct trace_event_buffer fbuffer;
574 struct synth_trace_event *entry;
575 struct trace_buffer *buffer;
576 struct synth_event *event;
577 unsigned int cur_field;
578 unsigned int n_u64;
579 bool disabled;
580 bool add_next;
581 bool add_name;
582 };
583
584 extern int synth_event_trace(struct trace_event_file *file,
585 unsigned int n_vals, ...);
586 extern int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
587 unsigned int n_vals);
588 extern int synth_event_trace_start(struct trace_event_file *file,
589 struct synth_event_trace_state *trace_state);
590 extern int synth_event_add_next_val(u64 val,
591 struct synth_event_trace_state *trace_state);
592 extern int synth_event_add_val(const char *field_name, u64 val,
593 struct synth_event_trace_state *trace_state);
594 extern int synth_event_trace_end(struct synth_event_trace_state *trace_state);
595
596 extern int kprobe_event_delete(const char *name);
597
598 extern void kprobe_event_cmd_init(struct dynevent_cmd *cmd,
599 char *buf, int maxlen);
600
601 #define kprobe_event_gen_cmd_start(cmd, name, loc, ...) \
602 __kprobe_event_gen_cmd_start(cmd, false, name, loc, ## __VA_ARGS__, NULL)
603
604 #define kretprobe_event_gen_cmd_start(cmd, name, loc, ...) \
605 __kprobe_event_gen_cmd_start(cmd, true, name, loc, ## __VA_ARGS__, NULL)
606
607 extern int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd,
608 bool kretprobe,
609 const char *name,
610 const char *loc, ...);
611
612 #define kprobe_event_add_fields(cmd, ...) \
613 __kprobe_event_add_fields(cmd, ## __VA_ARGS__, NULL)
614
615 #define kprobe_event_add_field(cmd, field) \
616 __kprobe_event_add_fields(cmd, field, NULL)
617
618 extern int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...);
619
620 #define kprobe_event_gen_cmd_end(cmd) \
621 dynevent_create(cmd)
622
623 #define kretprobe_event_gen_cmd_end(cmd) \
624 dynevent_create(cmd)
625
626 /*
627 * Event file flags:
628 * ENABLED - The event is enabled
629 * RECORDED_CMD - The comms should be recorded at sched_switch
630 * RECORDED_TGID - The tgids should be recorded at sched_switch
631 * FILTERED - The event has a filter attached
632 * NO_SET_FILTER - Set when filter has error and is to be ignored
633 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
634 * SOFT_DISABLED - When set, do not trace the event (even though its
635 * tracepoint may be enabled)
636 * TRIGGER_MODE - When set, invoke the triggers associated with the event
637 * TRIGGER_COND - When set, one or more triggers has an associated filter
638 * PID_FILTER - When set, the event is filtered based on pid
639 * WAS_ENABLED - Set when enabled to know to clear trace on module removal
640 * FREED - File descriptor is freed, all fields should be considered invalid
641 */
642 enum {
643 EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT),
644 EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
645 EVENT_FILE_FL_RECORDED_TGID = (1 << EVENT_FILE_FL_RECORDED_TGID_BIT),
646 EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT),
647 EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
648 EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT),
649 EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
650 EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
651 EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
652 EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT),
653 EVENT_FILE_FL_WAS_ENABLED = (1 << EVENT_FILE_FL_WAS_ENABLED_BIT),
654 EVENT_FILE_FL_FREED = (1 << EVENT_FILE_FL_FREED_BIT),
655 };
656
657 struct trace_event_file {
658 struct list_head list;
659 struct trace_event_call *event_call;
660 struct event_filter __rcu *filter;
661 struct eventfs_inode *ei;
662 struct trace_array *tr;
663 struct trace_subsystem_dir *system;
664 struct list_head triggers;
665
666 /*
667 * 32 bit flags:
668 * bit 0: enabled
669 * bit 1: enabled cmd record
670 * bit 2: enable/disable with the soft disable bit
671 * bit 3: soft disabled
672 * bit 4: trigger enabled
673 *
674 * Note: The bits must be set atomically to prevent races
675 * from other writers. Reads of flags do not need to be in
676 * sync as they occur in critical sections. But the way flags
677 * is currently used, these changes do not affect the code
678 * except that when a change is made, it may have a slight
679 * delay in propagating the changes to other CPUs due to
680 * caching and such. Which is mostly OK ;-)
681 */
682 unsigned long flags;
683 atomic_t ref; /* ref count for opened files */
684 atomic_t sm_ref; /* soft-mode reference counter */
685 atomic_t tm_ref; /* trigger-mode reference counter */
686 };
687
688 #define __TRACE_EVENT_FLAGS(name, value) \
689 static int __init trace_init_flags_##name(void) \
690 { \
691 event_##name.flags |= value; \
692 return 0; \
693 } \
694 early_initcall(trace_init_flags_##name);
695
696 #define __TRACE_EVENT_PERF_PERM(name, expr...) \
697 static int perf_perm_##name(struct trace_event_call *tp_event, \
698 struct perf_event *p_event) \
699 { \
700 return ({ expr; }); \
701 } \
702 static int __init trace_init_perf_perm_##name(void) \
703 { \
704 event_##name.perf_perm = &perf_perm_##name; \
705 return 0; \
706 } \
707 early_initcall(trace_init_perf_perm_##name);
708
709 #define PERF_MAX_TRACE_SIZE 8192
710
711 #define MAX_FILTER_STR_VAL 256U /* Should handle KSYM_SYMBOL_LEN */
712
713 enum event_trigger_type {
714 ETT_NONE = (0),
715 ETT_TRACE_ONOFF = (1 << 0),
716 ETT_SNAPSHOT = (1 << 1),
717 ETT_STACKTRACE = (1 << 2),
718 ETT_EVENT_ENABLE = (1 << 3),
719 ETT_EVENT_HIST = (1 << 4),
720 ETT_HIST_ENABLE = (1 << 5),
721 ETT_EVENT_EPROBE = (1 << 6),
722 };
723
724 extern int filter_match_preds(struct event_filter *filter, void *rec);
725
726 extern enum event_trigger_type
727 event_triggers_call(struct trace_event_file *file,
728 struct trace_buffer *buffer, void *rec,
729 struct ring_buffer_event *event);
730 extern void
731 event_triggers_post_call(struct trace_event_file *file,
732 enum event_trigger_type tt);
733
734 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
735
736 bool __trace_trigger_soft_disabled(struct trace_event_file *file);
737
738 /**
739 * trace_trigger_soft_disabled - do triggers and test if soft disabled
740 * @file: The file pointer of the event to test
741 *
742 * If any triggers without filters are attached to this event, they
743 * will be called here. If the event is soft disabled and has no
744 * triggers that require testing the fields, it will return true,
745 * otherwise false.
746 */
747 static __always_inline bool
trace_trigger_soft_disabled(struct trace_event_file * file)748 trace_trigger_soft_disabled(struct trace_event_file *file)
749 {
750 unsigned long eflags = file->flags;
751
752 if (likely(!(eflags & (EVENT_FILE_FL_TRIGGER_MODE |
753 EVENT_FILE_FL_SOFT_DISABLED |
754 EVENT_FILE_FL_PID_FILTER))))
755 return false;
756
757 if (likely(eflags & EVENT_FILE_FL_TRIGGER_COND))
758 return false;
759
760 return __trace_trigger_soft_disabled(file);
761 }
762
763 #ifdef CONFIG_BPF_EVENTS
764 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx);
765 int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
766 void perf_event_detach_bpf_prog(struct perf_event *event);
767 int perf_event_query_prog_array(struct perf_event *event, void __user *info);
768
769 struct bpf_raw_tp_link;
770 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
771 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
772
773 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name);
774 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp);
775 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
776 u32 *fd_type, const char **buf,
777 u64 *probe_offset, u64 *probe_addr,
778 unsigned long *missed);
779 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
780 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
781 #else
trace_call_bpf(struct trace_event_call * call,void * ctx)782 static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
783 {
784 return 1;
785 }
786
787 static inline int
perf_event_attach_bpf_prog(struct perf_event * event,struct bpf_prog * prog,u64 bpf_cookie)788 perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie)
789 {
790 return -EOPNOTSUPP;
791 }
792
perf_event_detach_bpf_prog(struct perf_event * event)793 static inline void perf_event_detach_bpf_prog(struct perf_event *event) { }
794
795 static inline int
perf_event_query_prog_array(struct perf_event * event,void __user * info)796 perf_event_query_prog_array(struct perf_event *event, void __user *info)
797 {
798 return -EOPNOTSUPP;
799 }
800 struct bpf_raw_tp_link;
bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_raw_tp_link * link)801 static inline int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
802 {
803 return -EOPNOTSUPP;
804 }
bpf_probe_unregister(struct bpf_raw_event_map * btp,struct bpf_raw_tp_link * link)805 static inline int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
806 {
807 return -EOPNOTSUPP;
808 }
bpf_get_raw_tracepoint(const char * name)809 static inline struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
810 {
811 return NULL;
812 }
bpf_put_raw_tracepoint(struct bpf_raw_event_map * btp)813 static inline void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
814 {
815 }
bpf_get_perf_event_info(const struct perf_event * event,u32 * prog_id,u32 * fd_type,const char ** buf,u64 * probe_offset,u64 * probe_addr,unsigned long * missed)816 static inline int bpf_get_perf_event_info(const struct perf_event *event,
817 u32 *prog_id, u32 *fd_type,
818 const char **buf, u64 *probe_offset,
819 u64 *probe_addr, unsigned long *missed)
820 {
821 return -EOPNOTSUPP;
822 }
823 static inline int
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)824 bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
825 {
826 return -EOPNOTSUPP;
827 }
828 static inline int
bpf_uprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)829 bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
830 {
831 return -EOPNOTSUPP;
832 }
833 #endif
834
835 enum {
836 FILTER_OTHER = 0,
837 FILTER_STATIC_STRING,
838 FILTER_DYN_STRING,
839 FILTER_RDYN_STRING,
840 FILTER_PTR_STRING,
841 FILTER_TRACE_FN,
842 FILTER_CPUMASK,
843 FILTER_COMM,
844 FILTER_CPU,
845 FILTER_STACKTRACE,
846 };
847
848 extern int trace_event_raw_init(struct trace_event_call *call);
849 extern int trace_define_field(struct trace_event_call *call, const char *type,
850 const char *name, int offset, int size,
851 int is_signed, int filter_type);
852 extern int trace_add_event_call(struct trace_event_call *call);
853 extern int trace_remove_event_call(struct trace_event_call *call);
854 extern int trace_event_get_offsets(struct trace_event_call *call);
855
856 int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
857 int trace_set_clr_event(const char *system, const char *event, int set);
858 int trace_array_set_clr_event(struct trace_array *tr, const char *system,
859 const char *event, bool enable);
860 /*
861 * The double __builtin_constant_p is because gcc will give us an error
862 * if we try to allocate the static variable to fmt if it is not a
863 * constant. Even with the outer if statement optimizing out.
864 */
865 #define event_trace_printk(ip, fmt, args...) \
866 do { \
867 __trace_printk_check_format(fmt, ##args); \
868 tracing_record_cmdline(current); \
869 if (__builtin_constant_p(fmt)) { \
870 static const char *trace_printk_fmt \
871 __section("__trace_printk_fmt") = \
872 __builtin_constant_p(fmt) ? fmt : NULL; \
873 \
874 __trace_bprintk(ip, trace_printk_fmt, ##args); \
875 } else \
876 __trace_printk(ip, fmt, ##args); \
877 } while (0)
878
879 #ifdef CONFIG_PERF_EVENTS
880 struct perf_event;
881
882 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
883 DECLARE_PER_CPU(int, bpf_kprobe_override);
884
885 extern int perf_trace_init(struct perf_event *event);
886 extern void perf_trace_destroy(struct perf_event *event);
887 extern int perf_trace_add(struct perf_event *event, int flags);
888 extern void perf_trace_del(struct perf_event *event, int flags);
889 #ifdef CONFIG_KPROBE_EVENTS
890 extern int perf_kprobe_init(struct perf_event *event, bool is_retprobe);
891 extern void perf_kprobe_destroy(struct perf_event *event);
892 extern int bpf_get_kprobe_info(const struct perf_event *event,
893 u32 *fd_type, const char **symbol,
894 u64 *probe_offset, u64 *probe_addr,
895 unsigned long *missed,
896 bool perf_type_tracepoint);
897 #endif
898 #ifdef CONFIG_UPROBE_EVENTS
899 extern int perf_uprobe_init(struct perf_event *event,
900 unsigned long ref_ctr_offset, bool is_retprobe);
901 extern void perf_uprobe_destroy(struct perf_event *event);
902 extern int bpf_get_uprobe_info(const struct perf_event *event,
903 u32 *fd_type, const char **filename,
904 u64 *probe_offset, u64 *probe_addr,
905 bool perf_type_tracepoint);
906 #endif
907 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
908 char *filter_str);
909 extern void ftrace_profile_free_filter(struct perf_event *event);
910 void perf_trace_buf_update(void *record, u16 type);
911 void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp);
912
913 int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
914 void perf_event_free_bpf_prog(struct perf_event *event);
915
916 void bpf_trace_run1(struct bpf_raw_tp_link *link, u64 arg1);
917 void bpf_trace_run2(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2);
918 void bpf_trace_run3(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
919 u64 arg3);
920 void bpf_trace_run4(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
921 u64 arg3, u64 arg4);
922 void bpf_trace_run5(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
923 u64 arg3, u64 arg4, u64 arg5);
924 void bpf_trace_run6(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
925 u64 arg3, u64 arg4, u64 arg5, u64 arg6);
926 void bpf_trace_run7(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
927 u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7);
928 void bpf_trace_run8(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
929 u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
930 u64 arg8);
931 void bpf_trace_run9(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
932 u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
933 u64 arg8, u64 arg9);
934 void bpf_trace_run10(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
935 u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
936 u64 arg8, u64 arg9, u64 arg10);
937 void bpf_trace_run11(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
938 u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
939 u64 arg8, u64 arg9, u64 arg10, u64 arg11);
940 void bpf_trace_run12(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
941 u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
942 u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12);
943 void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
944 struct trace_event_call *call, u64 count,
945 struct pt_regs *regs, struct hlist_head *head,
946 struct task_struct *task);
947
948 static inline void
perf_trace_buf_submit(void * raw_data,int size,int rctx,u16 type,u64 count,struct pt_regs * regs,void * head,struct task_struct * task)949 perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type,
950 u64 count, struct pt_regs *regs, void *head,
951 struct task_struct *task)
952 {
953 perf_tp_event(type, count, raw_data, size, regs, head, rctx, task);
954 }
955
956 #endif
957
958 #define TRACE_EVENT_STR_MAX 512
959
960 /*
961 * gcc warns that you can not use a va_list in an inlined
962 * function. But lets me make it into a macro :-/
963 */
964 #define __trace_event_vstr_len(fmt, va) \
965 ({ \
966 va_list __ap; \
967 int __ret; \
968 \
969 va_copy(__ap, *(va)); \
970 __ret = vsnprintf(NULL, 0, fmt, __ap) + 1; \
971 va_end(__ap); \
972 \
973 min(__ret, TRACE_EVENT_STR_MAX); \
974 })
975
976 #endif /* _LINUX_TRACE_EVENT_H */
977
978 /*
979 * Note: we keep the TRACE_CUSTOM_EVENT outside the include file ifdef protection.
980 * This is due to the way trace custom events work. If a file includes two
981 * trace event headers under one "CREATE_CUSTOM_TRACE_EVENTS" the first include
982 * will override the TRACE_CUSTOM_EVENT and break the second include.
983 */
984
985 #ifndef TRACE_CUSTOM_EVENT
986
987 #define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print)
988 #define DEFINE_CUSTOM_EVENT(template, name, proto, args)
989 #define TRACE_CUSTOM_EVENT(name, proto, args, struct, assign, print)
990
991 #endif /* ifdef TRACE_CUSTOM_EVENT (see note above) */
992