Linux kernel mirror (for testing)
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linux
1
2#ifndef _LINUX_TRACE_EVENT_H
3#define _LINUX_TRACE_EVENT_H
4
5#include <linux/ring_buffer.h>
6#include <linux/trace_seq.h>
7#include <linux/percpu.h>
8#include <linux/hardirq.h>
9#include <linux/perf_event.h>
10#include <linux/tracepoint.h>
11
12struct trace_array;
13struct trace_buffer;
14struct tracer;
15struct dentry;
16struct bpf_prog;
17
18const char *trace_print_flags_seq(struct trace_seq *p, const char *delim,
19 unsigned long flags,
20 const struct trace_print_flags *flag_array);
21
22const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
23 const struct trace_print_flags *symbol_array);
24
25#if BITS_PER_LONG == 32
26const char *trace_print_symbols_seq_u64(struct trace_seq *p,
27 unsigned long long val,
28 const struct trace_print_flags_u64
29 *symbol_array);
30#endif
31
32const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
33 unsigned int bitmask_size);
34
35const char *trace_print_hex_seq(struct trace_seq *p,
36 const unsigned char *buf, int len);
37
38const char *trace_print_array_seq(struct trace_seq *p,
39 const void *buf, int count,
40 size_t el_size);
41
42struct trace_iterator;
43struct trace_event;
44
45int trace_raw_output_prep(struct trace_iterator *iter,
46 struct trace_event *event);
47
48/*
49 * The trace entry - the most basic unit of tracing. This is what
50 * is printed in the end as a single line in the trace output, such as:
51 *
52 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
53 */
54struct trace_entry {
55 unsigned short type;
56 unsigned char flags;
57 unsigned char preempt_count;
58 int pid;
59};
60
61#define TRACE_EVENT_TYPE_MAX \
62 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
63
64/*
65 * Trace iterator - used by printout routines who present trace
66 * results to users and which routines might sleep, etc:
67 */
68struct trace_iterator {
69 struct trace_array *tr;
70 struct tracer *trace;
71 struct trace_buffer *trace_buffer;
72 void *private;
73 int cpu_file;
74 struct mutex mutex;
75 struct ring_buffer_iter **buffer_iter;
76 unsigned long iter_flags;
77
78 /* trace_seq for __print_flags() and __print_symbolic() etc. */
79 struct trace_seq tmp_seq;
80
81 cpumask_var_t started;
82
83 /* it's true when current open file is snapshot */
84 bool snapshot;
85
86 /* The below is zeroed out in pipe_read */
87 struct trace_seq seq;
88 struct trace_entry *ent;
89 unsigned long lost_events;
90 int leftover;
91 int ent_size;
92 int cpu;
93 u64 ts;
94
95 loff_t pos;
96 long idx;
97
98 /* All new field here will be zeroed out in pipe_read */
99};
100
101enum trace_iter_flags {
102 TRACE_FILE_LAT_FMT = 1,
103 TRACE_FILE_ANNOTATE = 2,
104 TRACE_FILE_TIME_IN_NS = 4,
105};
106
107
108typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
109 int flags, struct trace_event *event);
110
111struct trace_event_functions {
112 trace_print_func trace;
113 trace_print_func raw;
114 trace_print_func hex;
115 trace_print_func binary;
116};
117
118struct trace_event {
119 struct hlist_node node;
120 struct list_head list;
121 int type;
122 struct trace_event_functions *funcs;
123};
124
125extern int register_trace_event(struct trace_event *event);
126extern int unregister_trace_event(struct trace_event *event);
127
128/* Return values for print_line callback */
129enum print_line_t {
130 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
131 TRACE_TYPE_HANDLED = 1,
132 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */
133 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */
134};
135
136/*
137 * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq
138 * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function
139 * simplifies those functions and keeps them in sync.
140 */
141static inline enum print_line_t trace_handle_return(struct trace_seq *s)
142{
143 return trace_seq_has_overflowed(s) ?
144 TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED;
145}
146
147void tracing_generic_entry_update(struct trace_entry *entry,
148 unsigned long flags,
149 int pc);
150struct trace_event_file;
151
152struct ring_buffer_event *
153trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
154 struct trace_event_file *trace_file,
155 int type, unsigned long len,
156 unsigned long flags, int pc);
157
158void tracing_record_cmdline(struct task_struct *tsk);
159
160int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...);
161
162struct event_filter;
163
164enum trace_reg {
165 TRACE_REG_REGISTER,
166 TRACE_REG_UNREGISTER,
167#ifdef CONFIG_PERF_EVENTS
168 TRACE_REG_PERF_REGISTER,
169 TRACE_REG_PERF_UNREGISTER,
170 TRACE_REG_PERF_OPEN,
171 TRACE_REG_PERF_CLOSE,
172 TRACE_REG_PERF_ADD,
173 TRACE_REG_PERF_DEL,
174#endif
175};
176
177struct trace_event_call;
178
179struct trace_event_class {
180 const char *system;
181 void *probe;
182#ifdef CONFIG_PERF_EVENTS
183 void *perf_probe;
184#endif
185 int (*reg)(struct trace_event_call *event,
186 enum trace_reg type, void *data);
187 int (*define_fields)(struct trace_event_call *);
188 struct list_head *(*get_fields)(struct trace_event_call *);
189 struct list_head fields;
190 int (*raw_init)(struct trace_event_call *);
191};
192
193extern int trace_event_reg(struct trace_event_call *event,
194 enum trace_reg type, void *data);
195
196struct trace_event_buffer {
197 struct ring_buffer *buffer;
198 struct ring_buffer_event *event;
199 struct trace_event_file *trace_file;
200 void *entry;
201 unsigned long flags;
202 int pc;
203};
204
205void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
206 struct trace_event_file *trace_file,
207 unsigned long len);
208
209void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);
210
211enum {
212 TRACE_EVENT_FL_FILTERED_BIT,
213 TRACE_EVENT_FL_CAP_ANY_BIT,
214 TRACE_EVENT_FL_NO_SET_FILTER_BIT,
215 TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
216 TRACE_EVENT_FL_WAS_ENABLED_BIT,
217 TRACE_EVENT_FL_TRACEPOINT_BIT,
218 TRACE_EVENT_FL_KPROBE_BIT,
219 TRACE_EVENT_FL_UPROBE_BIT,
220};
221
222/*
223 * Event flags:
224 * FILTERED - The event has a filter attached
225 * CAP_ANY - Any user can enable for perf
226 * NO_SET_FILTER - Set when filter has error and is to be ignored
227 * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
228 * WAS_ENABLED - Set and stays set when an event was ever enabled
229 * (used for module unloading, if a module event is enabled,
230 * it is best to clear the buffers that used it).
231 * TRACEPOINT - Event is a tracepoint
232 * KPROBE - Event is a kprobe
233 * UPROBE - Event is a uprobe
234 */
235enum {
236 TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
237 TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
238 TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
239 TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
240 TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
241 TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
242 TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT),
243 TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT),
244};
245
246#define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
247
248struct trace_event_call {
249 struct list_head list;
250 struct trace_event_class *class;
251 union {
252 char *name;
253 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
254 struct tracepoint *tp;
255 };
256 struct trace_event event;
257 char *print_fmt;
258 struct event_filter *filter;
259 void *mod;
260 void *data;
261 /*
262 * bit 0: filter_active
263 * bit 1: allow trace by non root (cap any)
264 * bit 2: failed to apply filter
265 * bit 3: trace internal event (do not enable)
266 * bit 4: Event was enabled by module
267 * bit 5: use call filter rather than file filter
268 * bit 6: Event is a tracepoint
269 */
270 int flags; /* static flags of different events */
271
272#ifdef CONFIG_PERF_EVENTS
273 int perf_refcount;
274 struct hlist_head __percpu *perf_events;
275 struct bpf_prog *prog;
276
277 int (*perf_perm)(struct trace_event_call *,
278 struct perf_event *);
279#endif
280};
281
282static inline const char *
283trace_event_name(struct trace_event_call *call)
284{
285 if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
286 return call->tp ? call->tp->name : NULL;
287 else
288 return call->name;
289}
290
291struct trace_array;
292struct trace_subsystem_dir;
293
294enum {
295 EVENT_FILE_FL_ENABLED_BIT,
296 EVENT_FILE_FL_RECORDED_CMD_BIT,
297 EVENT_FILE_FL_FILTERED_BIT,
298 EVENT_FILE_FL_NO_SET_FILTER_BIT,
299 EVENT_FILE_FL_SOFT_MODE_BIT,
300 EVENT_FILE_FL_SOFT_DISABLED_BIT,
301 EVENT_FILE_FL_TRIGGER_MODE_BIT,
302 EVENT_FILE_FL_TRIGGER_COND_BIT,
303 EVENT_FILE_FL_PID_FILTER_BIT,
304};
305
306/*
307 * Event file flags:
308 * ENABLED - The event is enabled
309 * RECORDED_CMD - The comms should be recorded at sched_switch
310 * FILTERED - The event has a filter attached
311 * NO_SET_FILTER - Set when filter has error and is to be ignored
312 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
313 * SOFT_DISABLED - When set, do not trace the event (even though its
314 * tracepoint may be enabled)
315 * TRIGGER_MODE - When set, invoke the triggers associated with the event
316 * TRIGGER_COND - When set, one or more triggers has an associated filter
317 * PID_FILTER - When set, the event is filtered based on pid
318 */
319enum {
320 EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT),
321 EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
322 EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT),
323 EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
324 EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT),
325 EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
326 EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
327 EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
328 EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT),
329};
330
331struct trace_event_file {
332 struct list_head list;
333 struct trace_event_call *event_call;
334 struct event_filter *filter;
335 struct dentry *dir;
336 struct trace_array *tr;
337 struct trace_subsystem_dir *system;
338 struct list_head triggers;
339
340 /*
341 * 32 bit flags:
342 * bit 0: enabled
343 * bit 1: enabled cmd record
344 * bit 2: enable/disable with the soft disable bit
345 * bit 3: soft disabled
346 * bit 4: trigger enabled
347 *
348 * Note: The bits must be set atomically to prevent races
349 * from other writers. Reads of flags do not need to be in
350 * sync as they occur in critical sections. But the way flags
351 * is currently used, these changes do not affect the code
352 * except that when a change is made, it may have a slight
353 * delay in propagating the changes to other CPUs due to
354 * caching and such. Which is mostly OK ;-)
355 */
356 unsigned long flags;
357 atomic_t sm_ref; /* soft-mode reference counter */
358 atomic_t tm_ref; /* trigger-mode reference counter */
359};
360
361#define __TRACE_EVENT_FLAGS(name, value) \
362 static int __init trace_init_flags_##name(void) \
363 { \
364 event_##name.flags |= value; \
365 return 0; \
366 } \
367 early_initcall(trace_init_flags_##name);
368
369#define __TRACE_EVENT_PERF_PERM(name, expr...) \
370 static int perf_perm_##name(struct trace_event_call *tp_event, \
371 struct perf_event *p_event) \
372 { \
373 return ({ expr; }); \
374 } \
375 static int __init trace_init_perf_perm_##name(void) \
376 { \
377 event_##name.perf_perm = &perf_perm_##name; \
378 return 0; \
379 } \
380 early_initcall(trace_init_perf_perm_##name);
381
382#define PERF_MAX_TRACE_SIZE 2048
383
384#define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
385
386enum event_trigger_type {
387 ETT_NONE = (0),
388 ETT_TRACE_ONOFF = (1 << 0),
389 ETT_SNAPSHOT = (1 << 1),
390 ETT_STACKTRACE = (1 << 2),
391 ETT_EVENT_ENABLE = (1 << 3),
392 ETT_EVENT_HIST = (1 << 4),
393 ETT_HIST_ENABLE = (1 << 5),
394};
395
396extern int filter_match_preds(struct event_filter *filter, void *rec);
397
398extern enum event_trigger_type event_triggers_call(struct trace_event_file *file,
399 void *rec);
400extern void event_triggers_post_call(struct trace_event_file *file,
401 enum event_trigger_type tt,
402 void *rec);
403
404bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
405
406/**
407 * trace_trigger_soft_disabled - do triggers and test if soft disabled
408 * @file: The file pointer of the event to test
409 *
410 * If any triggers without filters are attached to this event, they
411 * will be called here. If the event is soft disabled and has no
412 * triggers that require testing the fields, it will return true,
413 * otherwise false.
414 */
415static inline bool
416trace_trigger_soft_disabled(struct trace_event_file *file)
417{
418 unsigned long eflags = file->flags;
419
420 if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) {
421 if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
422 event_triggers_call(file, NULL);
423 if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
424 return true;
425 if (eflags & EVENT_FILE_FL_PID_FILTER)
426 return trace_event_ignore_this_pid(file);
427 }
428 return false;
429}
430
431#ifdef CONFIG_BPF_EVENTS
432unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx);
433#else
434static inline unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx)
435{
436 return 1;
437}
438#endif
439
440enum {
441 FILTER_OTHER = 0,
442 FILTER_STATIC_STRING,
443 FILTER_DYN_STRING,
444 FILTER_PTR_STRING,
445 FILTER_TRACE_FN,
446 FILTER_COMM,
447 FILTER_CPU,
448};
449
450extern int trace_event_raw_init(struct trace_event_call *call);
451extern int trace_define_field(struct trace_event_call *call, const char *type,
452 const char *name, int offset, int size,
453 int is_signed, int filter_type);
454extern int trace_add_event_call(struct trace_event_call *call);
455extern int trace_remove_event_call(struct trace_event_call *call);
456extern int trace_event_get_offsets(struct trace_event_call *call);
457
458#define is_signed_type(type) (((type)(-1)) < (type)1)
459
460int trace_set_clr_event(const char *system, const char *event, int set);
461
462/*
463 * The double __builtin_constant_p is because gcc will give us an error
464 * if we try to allocate the static variable to fmt if it is not a
465 * constant. Even with the outer if statement optimizing out.
466 */
467#define event_trace_printk(ip, fmt, args...) \
468do { \
469 __trace_printk_check_format(fmt, ##args); \
470 tracing_record_cmdline(current); \
471 if (__builtin_constant_p(fmt)) { \
472 static const char *trace_printk_fmt \
473 __attribute__((section("__trace_printk_fmt"))) = \
474 __builtin_constant_p(fmt) ? fmt : NULL; \
475 \
476 __trace_bprintk(ip, trace_printk_fmt, ##args); \
477 } else \
478 __trace_printk(ip, fmt, ##args); \
479} while (0)
480
481#ifdef CONFIG_PERF_EVENTS
482struct perf_event;
483
484DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
485
486extern int perf_trace_init(struct perf_event *event);
487extern void perf_trace_destroy(struct perf_event *event);
488extern int perf_trace_add(struct perf_event *event, int flags);
489extern void perf_trace_del(struct perf_event *event, int flags);
490extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
491 char *filter_str);
492extern void ftrace_profile_free_filter(struct perf_event *event);
493void perf_trace_buf_update(void *record, u16 type);
494void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp);
495
496void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
497 struct trace_event_call *call, u64 count,
498 struct pt_regs *regs, struct hlist_head *head,
499 struct task_struct *task);
500
501static inline void
502perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type,
503 u64 count, struct pt_regs *regs, void *head,
504 struct task_struct *task)
505{
506 perf_tp_event(type, count, raw_data, size, regs, head, rctx, task);
507}
508#endif
509
510#endif /* _LINUX_TRACE_EVENT_H */