1 // SPDX-License-Identifier: GPL-2.0
2
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
5
6 #include <linux/fs.h>
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/trace.h>
15 #include <linux/hw_breakpoint.h>
16 #include <linux/trace_seq.h>
17 #include <linux/trace_events.h>
18 #include <linux/compiler.h>
19 #include <linux/glob.h>
20 #include <linux/irq_work.h>
21 #include <linux/workqueue.h>
22 #include <linux/ctype.h>
23 #include <linux/once_lite.h>
24
25 #include "pid_list.h"
26
27 #ifdef CONFIG_FTRACE_SYSCALLS
28 #include <asm/unistd.h> /* For NR_syscalls */
29 #include <asm/syscall.h> /* some archs define it here */
30 #endif
31
32 #define TRACE_MODE_WRITE 0640
33 #define TRACE_MODE_READ 0440
34
35 enum trace_type {
36 __TRACE_FIRST_TYPE = 0,
37
38 TRACE_FN,
39 TRACE_CTX,
40 TRACE_WAKE,
41 TRACE_STACK,
42 TRACE_PRINT,
43 TRACE_BPRINT,
44 TRACE_MMIO_RW,
45 TRACE_MMIO_MAP,
46 TRACE_BRANCH,
47 TRACE_GRAPH_RET,
48 TRACE_GRAPH_ENT,
49 TRACE_USER_STACK,
50 TRACE_BLK,
51 TRACE_BPUTS,
52 TRACE_HWLAT,
53 TRACE_OSNOISE,
54 TRACE_TIMERLAT,
55 TRACE_RAW_DATA,
56 TRACE_FUNC_REPEATS,
57
58 __TRACE_LAST_TYPE,
59 };
60
61
62 #undef __field
63 #define __field(type, item) type item;
64
65 #undef __field_fn
66 #define __field_fn(type, item) type item;
67
68 #undef __field_struct
69 #define __field_struct(type, item) __field(type, item)
70
71 #undef __field_desc
72 #define __field_desc(type, container, item)
73
74 #undef __field_packed
75 #define __field_packed(type, container, item)
76
77 #undef __array
78 #define __array(type, item, size) type item[size];
79
80 /*
81 * For backward compatibility, older user space expects to see the
82 * kernel_stack event with a fixed size caller field. But today the fix
83 * size is ignored by the kernel, and the real structure is dynamic.
84 * Expose to user space: "unsigned long caller[8];" but the real structure
85 * will be "unsigned long caller[] __counted_by(size)"
86 */
87 #undef __stack_array
88 #define __stack_array(type, item, size, field) type item[] __counted_by(field);
89
90 #undef __array_desc
91 #define __array_desc(type, container, item, size)
92
93 #undef __dynamic_array
94 #define __dynamic_array(type, item) type item[];
95
96 #undef __rel_dynamic_array
97 #define __rel_dynamic_array(type, item) type item[];
98
99 #undef F_STRUCT
100 #define F_STRUCT(args...) args
101
102 #undef FTRACE_ENTRY
103 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
104 struct struct_name { \
105 struct trace_entry ent; \
106 tstruct \
107 }
108
109 #undef FTRACE_ENTRY_DUP
110 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
111
112 #undef FTRACE_ENTRY_REG
113 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \
114 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
115
116 #undef FTRACE_ENTRY_PACKED
117 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \
118 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
119
120 #include "trace_entries.h"
121
122 /* Use this for memory failure errors */
123 #define MEM_FAIL(condition, fmt, ...) \
124 DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
125
126 #define FAULT_STRING "(fault)"
127
128 #define HIST_STACKTRACE_DEPTH 16
129 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
130 #define HIST_STACKTRACE_SKIP 5
131
132 /*
133 * syscalls are special, and need special handling, this is why
134 * they are not included in trace_entries.h
135 */
136 struct syscall_trace_enter {
137 struct trace_entry ent;
138 int nr;
139 unsigned long args[];
140 };
141
142 struct syscall_trace_exit {
143 struct trace_entry ent;
144 int nr;
145 long ret;
146 };
147
148 struct kprobe_trace_entry_head {
149 struct trace_entry ent;
150 unsigned long ip;
151 };
152
153 struct eprobe_trace_entry_head {
154 struct trace_entry ent;
155 };
156
157 struct kretprobe_trace_entry_head {
158 struct trace_entry ent;
159 unsigned long func;
160 unsigned long ret_ip;
161 };
162
163 struct fentry_trace_entry_head {
164 struct trace_entry ent;
165 unsigned long ip;
166 };
167
168 struct fexit_trace_entry_head {
169 struct trace_entry ent;
170 unsigned long func;
171 unsigned long ret_ip;
172 };
173
174 #define TRACE_BUF_SIZE 1024
175
176 struct trace_array;
177
178 /*
179 * The CPU trace array - it consists of thousands of trace entries
180 * plus some other descriptor data: (for example which task started
181 * the trace, etc.)
182 */
183 struct trace_array_cpu {
184 atomic_t disabled;
185 void *buffer_page; /* ring buffer spare */
186
187 unsigned long entries;
188 unsigned long saved_latency;
189 unsigned long critical_start;
190 unsigned long critical_end;
191 unsigned long critical_sequence;
192 unsigned long nice;
193 unsigned long policy;
194 unsigned long rt_priority;
195 unsigned long skipped_entries;
196 u64 preempt_timestamp;
197 pid_t pid;
198 kuid_t uid;
199 char comm[TASK_COMM_LEN];
200
201 #ifdef CONFIG_FUNCTION_TRACER
202 int ftrace_ignore_pid;
203 #endif
204 bool ignore_pid;
205 };
206
207 struct tracer;
208 struct trace_option_dentry;
209
210 struct array_buffer {
211 struct trace_array *tr;
212 struct trace_buffer *buffer;
213 struct trace_array_cpu __percpu *data;
214 u64 time_start;
215 int cpu;
216 };
217
218 #define TRACE_FLAGS_MAX_SIZE 32
219
220 struct trace_options {
221 struct tracer *tracer;
222 struct trace_option_dentry *topts;
223 };
224
225 struct trace_pid_list *trace_pid_list_alloc(void);
226 void trace_pid_list_free(struct trace_pid_list *pid_list);
227 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
228 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
229 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
230 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
231 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
232 unsigned int *next);
233
234 enum {
235 TRACE_PIDS = BIT(0),
236 TRACE_NO_PIDS = BIT(1),
237 };
238
pid_type_enabled(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)239 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
240 struct trace_pid_list *no_pid_list)
241 {
242 /* Return true if the pid list in type has pids */
243 return ((type & TRACE_PIDS) && pid_list) ||
244 ((type & TRACE_NO_PIDS) && no_pid_list);
245 }
246
still_need_pid_events(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)247 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
248 struct trace_pid_list *no_pid_list)
249 {
250 /*
251 * Turning off what is in @type, return true if the "other"
252 * pid list, still has pids in it.
253 */
254 return (!(type & TRACE_PIDS) && pid_list) ||
255 (!(type & TRACE_NO_PIDS) && no_pid_list);
256 }
257
258 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
259
260 /**
261 * struct cond_snapshot - conditional snapshot data and callback
262 *
263 * The cond_snapshot structure encapsulates a callback function and
264 * data associated with the snapshot for a given tracing instance.
265 *
266 * When a snapshot is taken conditionally, by invoking
267 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
268 * passed in turn to the cond_snapshot.update() function. That data
269 * can be compared by the update() implementation with the cond_data
270 * contained within the struct cond_snapshot instance associated with
271 * the trace_array. Because the tr->max_lock is held throughout the
272 * update() call, the update() function can directly retrieve the
273 * cond_snapshot and cond_data associated with the per-instance
274 * snapshot associated with the trace_array.
275 *
276 * The cond_snapshot.update() implementation can save data to be
277 * associated with the snapshot if it decides to, and returns 'true'
278 * in that case, or it returns 'false' if the conditional snapshot
279 * shouldn't be taken.
280 *
281 * The cond_snapshot instance is created and associated with the
282 * user-defined cond_data by tracing_cond_snapshot_enable().
283 * Likewise, the cond_snapshot instance is destroyed and is no longer
284 * associated with the trace instance by
285 * tracing_cond_snapshot_disable().
286 *
287 * The method below is required.
288 *
289 * @update: When a conditional snapshot is invoked, the update()
290 * callback function is invoked with the tr->max_lock held. The
291 * update() implementation signals whether or not to actually
292 * take the snapshot, by returning 'true' if so, 'false' if no
293 * snapshot should be taken. Because the max_lock is held for
294 * the duration of update(), the implementation is safe to
295 * directly retrieved and save any implementation data it needs
296 * to in association with the snapshot.
297 */
298 struct cond_snapshot {
299 void *cond_data;
300 cond_update_fn_t update;
301 };
302
303 /*
304 * struct trace_func_repeats - used to keep track of the consecutive
305 * (on the same CPU) calls of a single function.
306 */
307 struct trace_func_repeats {
308 unsigned long ip;
309 unsigned long parent_ip;
310 unsigned long count;
311 u64 ts_last_call;
312 };
313
314 /*
315 * The trace array - an array of per-CPU trace arrays. This is the
316 * highest level data structure that individual tracers deal with.
317 * They have on/off state as well:
318 */
319 struct trace_array {
320 struct list_head list;
321 char *name;
322 struct array_buffer array_buffer;
323 #ifdef CONFIG_TRACER_MAX_TRACE
324 /*
325 * The max_buffer is used to snapshot the trace when a maximum
326 * latency is reached, or when the user initiates a snapshot.
327 * Some tracers will use this to store a maximum trace while
328 * it continues examining live traces.
329 *
330 * The buffers for the max_buffer are set up the same as the array_buffer
331 * When a snapshot is taken, the buffer of the max_buffer is swapped
332 * with the buffer of the array_buffer and the buffers are reset for
333 * the array_buffer so the tracing can continue.
334 */
335 struct array_buffer max_buffer;
336 bool allocated_snapshot;
337 #endif
338 #ifdef CONFIG_TRACER_MAX_TRACE
339 unsigned long max_latency;
340 #ifdef CONFIG_FSNOTIFY
341 struct dentry *d_max_latency;
342 struct work_struct fsnotify_work;
343 struct irq_work fsnotify_irqwork;
344 #endif
345 #endif
346 struct trace_pid_list __rcu *filtered_pids;
347 struct trace_pid_list __rcu *filtered_no_pids;
348 /*
349 * max_lock is used to protect the swapping of buffers
350 * when taking a max snapshot. The buffers themselves are
351 * protected by per_cpu spinlocks. But the action of the swap
352 * needs its own lock.
353 *
354 * This is defined as a arch_spinlock_t in order to help
355 * with performance when lockdep debugging is enabled.
356 *
357 * It is also used in other places outside the update_max_tr
358 * so it needs to be defined outside of the
359 * CONFIG_TRACER_MAX_TRACE.
360 */
361 arch_spinlock_t max_lock;
362 int buffer_disabled;
363 #ifdef CONFIG_FTRACE_SYSCALLS
364 int sys_refcount_enter;
365 int sys_refcount_exit;
366 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
367 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
368 #endif
369 int stop_count;
370 int clock_id;
371 int nr_topts;
372 bool clear_trace;
373 int buffer_percent;
374 unsigned int n_err_log_entries;
375 struct tracer *current_trace;
376 unsigned int trace_flags;
377 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
378 unsigned int flags;
379 raw_spinlock_t start_lock;
380 struct list_head err_log;
381 struct dentry *dir;
382 struct dentry *options;
383 struct dentry *percpu_dir;
384 struct eventfs_inode *event_dir;
385 struct trace_options *topts;
386 struct list_head systems;
387 struct list_head events;
388 struct trace_event_file *trace_marker_file;
389 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
390 /* one per_cpu trace_pipe can be opened by only one user */
391 cpumask_var_t pipe_cpumask;
392 int ref;
393 int trace_ref;
394 #ifdef CONFIG_FUNCTION_TRACER
395 struct ftrace_ops *ops;
396 struct trace_pid_list __rcu *function_pids;
397 struct trace_pid_list __rcu *function_no_pids;
398 #ifdef CONFIG_DYNAMIC_FTRACE
399 /* All of these are protected by the ftrace_lock */
400 struct list_head func_probes;
401 struct list_head mod_trace;
402 struct list_head mod_notrace;
403 #endif
404 /* function tracing enabled */
405 int function_enabled;
406 #endif
407 int no_filter_buffering_ref;
408 struct list_head hist_vars;
409 #ifdef CONFIG_TRACER_SNAPSHOT
410 struct cond_snapshot *cond_snapshot;
411 #endif
412 struct trace_func_repeats __percpu *last_func_repeats;
413 };
414
415 enum {
416 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
417 };
418
419 extern struct list_head ftrace_trace_arrays;
420
421 extern struct mutex trace_types_lock;
422
423 extern int trace_array_get(struct trace_array *tr);
424 extern int tracing_check_open_get_tr(struct trace_array *tr);
425 extern struct trace_array *trace_array_find(const char *instance);
426 extern struct trace_array *trace_array_find_get(const char *instance);
427
428 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
429 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
430 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
431
432 extern bool trace_clock_in_ns(struct trace_array *tr);
433
434 /*
435 * The global tracer (top) should be the first trace array added,
436 * but we check the flag anyway.
437 */
top_trace_array(void)438 static inline struct trace_array *top_trace_array(void)
439 {
440 struct trace_array *tr;
441
442 if (list_empty(&ftrace_trace_arrays))
443 return NULL;
444
445 tr = list_entry(ftrace_trace_arrays.prev,
446 typeof(*tr), list);
447 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
448 return tr;
449 }
450
451 #define FTRACE_CMP_TYPE(var, type) \
452 __builtin_types_compatible_p(typeof(var), type *)
453
454 #undef IF_ASSIGN
455 #define IF_ASSIGN(var, entry, etype, id) \
456 if (FTRACE_CMP_TYPE(var, etype)) { \
457 var = (typeof(var))(entry); \
458 WARN_ON(id != 0 && (entry)->type != id); \
459 break; \
460 }
461
462 /* Will cause compile errors if type is not found. */
463 extern void __ftrace_bad_type(void);
464
465 /*
466 * The trace_assign_type is a verifier that the entry type is
467 * the same as the type being assigned. To add new types simply
468 * add a line with the following format:
469 *
470 * IF_ASSIGN(var, ent, type, id);
471 *
472 * Where "type" is the trace type that includes the trace_entry
473 * as the "ent" item. And "id" is the trace identifier that is
474 * used in the trace_type enum.
475 *
476 * If the type can have more than one id, then use zero.
477 */
478 #define trace_assign_type(var, ent) \
479 do { \
480 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
481 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
482 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
483 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
484 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
485 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
486 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
487 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
488 IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
489 IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
490 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
491 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
492 TRACE_MMIO_RW); \
493 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
494 TRACE_MMIO_MAP); \
495 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
496 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
497 TRACE_GRAPH_ENT); \
498 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
499 TRACE_GRAPH_RET); \
500 IF_ASSIGN(var, ent, struct func_repeats_entry, \
501 TRACE_FUNC_REPEATS); \
502 __ftrace_bad_type(); \
503 } while (0)
504
505 /*
506 * An option specific to a tracer. This is a boolean value.
507 * The bit is the bit index that sets its value on the
508 * flags value in struct tracer_flags.
509 */
510 struct tracer_opt {
511 const char *name; /* Will appear on the trace_options file */
512 u32 bit; /* Mask assigned in val field in tracer_flags */
513 };
514
515 /*
516 * The set of specific options for a tracer. Your tracer
517 * have to set the initial value of the flags val.
518 */
519 struct tracer_flags {
520 u32 val;
521 struct tracer_opt *opts;
522 struct tracer *trace;
523 };
524
525 /* Makes more easy to define a tracer opt */
526 #define TRACER_OPT(s, b) .name = #s, .bit = b
527
528
529 struct trace_option_dentry {
530 struct tracer_opt *opt;
531 struct tracer_flags *flags;
532 struct trace_array *tr;
533 struct dentry *entry;
534 };
535
536 /**
537 * struct tracer - a specific tracer and its callbacks to interact with tracefs
538 * @name: the name chosen to select it on the available_tracers file
539 * @init: called when one switches to this tracer (echo name > current_tracer)
540 * @reset: called when one switches to another tracer
541 * @start: called when tracing is unpaused (echo 1 > tracing_on)
542 * @stop: called when tracing is paused (echo 0 > tracing_on)
543 * @update_thresh: called when tracing_thresh is updated
544 * @open: called when the trace file is opened
545 * @pipe_open: called when the trace_pipe file is opened
546 * @close: called when the trace file is released
547 * @pipe_close: called when the trace_pipe file is released
548 * @read: override the default read callback on trace_pipe
549 * @splice_read: override the default splice_read callback on trace_pipe
550 * @selftest: selftest to run on boot (see trace_selftest.c)
551 * @print_headers: override the first lines that describe your columns
552 * @print_line: callback that prints a trace
553 * @set_flag: signals one of your private flags changed (trace_options file)
554 * @flags: your private flags
555 */
556 struct tracer {
557 const char *name;
558 int (*init)(struct trace_array *tr);
559 void (*reset)(struct trace_array *tr);
560 void (*start)(struct trace_array *tr);
561 void (*stop)(struct trace_array *tr);
562 int (*update_thresh)(struct trace_array *tr);
563 void (*open)(struct trace_iterator *iter);
564 void (*pipe_open)(struct trace_iterator *iter);
565 void (*close)(struct trace_iterator *iter);
566 void (*pipe_close)(struct trace_iterator *iter);
567 ssize_t (*read)(struct trace_iterator *iter,
568 struct file *filp, char __user *ubuf,
569 size_t cnt, loff_t *ppos);
570 ssize_t (*splice_read)(struct trace_iterator *iter,
571 struct file *filp,
572 loff_t *ppos,
573 struct pipe_inode_info *pipe,
574 size_t len,
575 unsigned int flags);
576 #ifdef CONFIG_FTRACE_STARTUP_TEST
577 int (*selftest)(struct tracer *trace,
578 struct trace_array *tr);
579 #endif
580 void (*print_header)(struct seq_file *m);
581 enum print_line_t (*print_line)(struct trace_iterator *iter);
582 /* If you handled the flag setting, return 0 */
583 int (*set_flag)(struct trace_array *tr,
584 u32 old_flags, u32 bit, int set);
585 /* Return 0 if OK with change, else return non-zero */
586 int (*flag_changed)(struct trace_array *tr,
587 u32 mask, int set);
588 struct tracer *next;
589 struct tracer_flags *flags;
590 int enabled;
591 bool print_max;
592 bool allow_instances;
593 #ifdef CONFIG_TRACER_MAX_TRACE
594 bool use_max_tr;
595 #endif
596 /* True if tracer cannot be enabled in kernel param */
597 bool noboot;
598 };
599
600 static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator * iter,int cpu)601 trace_buffer_iter(struct trace_iterator *iter, int cpu)
602 {
603 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
604 }
605
606 int tracer_init(struct tracer *t, struct trace_array *tr);
607 int tracing_is_enabled(void);
608 void tracing_reset_online_cpus(struct array_buffer *buf);
609 void tracing_reset_all_online_cpus(void);
610 void tracing_reset_all_online_cpus_unlocked(void);
611 int tracing_open_generic(struct inode *inode, struct file *filp);
612 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
613 int tracing_open_file_tr(struct inode *inode, struct file *filp);
614 int tracing_release_file_tr(struct inode *inode, struct file *filp);
615 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
616 bool tracing_is_disabled(void);
617 bool tracer_tracing_is_on(struct trace_array *tr);
618 void tracer_tracing_on(struct trace_array *tr);
619 void tracer_tracing_off(struct trace_array *tr);
620 struct dentry *trace_create_file(const char *name,
621 umode_t mode,
622 struct dentry *parent,
623 void *data,
624 const struct file_operations *fops);
625
626 int tracing_init_dentry(void);
627
628 struct ring_buffer_event;
629
630 struct ring_buffer_event *
631 trace_buffer_lock_reserve(struct trace_buffer *buffer,
632 int type,
633 unsigned long len,
634 unsigned int trace_ctx);
635
636 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
637 struct trace_array_cpu *data);
638
639 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
640 int *ent_cpu, u64 *ent_ts);
641
642 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
643 struct ring_buffer_event *event);
644
645 bool trace_is_tracepoint_string(const char *str);
646 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
647 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
648 va_list ap) __printf(2, 0);
649 char *trace_iter_expand_format(struct trace_iterator *iter);
650
651 int trace_empty(struct trace_iterator *iter);
652
653 void *trace_find_next_entry_inc(struct trace_iterator *iter);
654
655 void trace_init_global_iter(struct trace_iterator *iter);
656
657 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
658
659 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
660 unsigned long trace_total_entries(struct trace_array *tr);
661
662 void trace_function(struct trace_array *tr,
663 unsigned long ip,
664 unsigned long parent_ip,
665 unsigned int trace_ctx);
666 void trace_graph_function(struct trace_array *tr,
667 unsigned long ip,
668 unsigned long parent_ip,
669 unsigned int trace_ctx);
670 void trace_latency_header(struct seq_file *m);
671 void trace_default_header(struct seq_file *m);
672 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
673
674 void trace_graph_return(struct ftrace_graph_ret *trace);
675 int trace_graph_entry(struct ftrace_graph_ent *trace);
676 void set_graph_array(struct trace_array *tr);
677
678 void tracing_start_cmdline_record(void);
679 void tracing_stop_cmdline_record(void);
680 void tracing_start_tgid_record(void);
681 void tracing_stop_tgid_record(void);
682
683 int register_tracer(struct tracer *type);
684 int is_tracing_stopped(void);
685
686 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
687
688 extern cpumask_var_t __read_mostly tracing_buffer_mask;
689
690 #define for_each_tracing_cpu(cpu) \
691 for_each_cpu(cpu, tracing_buffer_mask)
692
693 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
694
695 extern unsigned long tracing_thresh;
696
697 /* PID filtering */
698
699 extern int pid_max;
700
701 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
702 pid_t search_pid);
703 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
704 struct trace_pid_list *filtered_no_pids,
705 struct task_struct *task);
706 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
707 struct task_struct *self,
708 struct task_struct *task);
709 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
710 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
711 int trace_pid_show(struct seq_file *m, void *v);
712 int trace_pid_write(struct trace_pid_list *filtered_pids,
713 struct trace_pid_list **new_pid_list,
714 const char __user *ubuf, size_t cnt);
715
716 #ifdef CONFIG_TRACER_MAX_TRACE
717 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
718 void *cond_data);
719 void update_max_tr_single(struct trace_array *tr,
720 struct task_struct *tsk, int cpu);
721
722 #ifdef CONFIG_FSNOTIFY
723 #define LATENCY_FS_NOTIFY
724 #endif
725 #endif /* CONFIG_TRACER_MAX_TRACE */
726
727 #ifdef LATENCY_FS_NOTIFY
728 void latency_fsnotify(struct trace_array *tr);
729 #else
latency_fsnotify(struct trace_array * tr)730 static inline void latency_fsnotify(struct trace_array *tr) { }
731 #endif
732
733 #ifdef CONFIG_STACKTRACE
734 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
735 #else
__trace_stack(struct trace_array * tr,unsigned int trace_ctx,int skip)736 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
737 int skip)
738 {
739 }
740 #endif /* CONFIG_STACKTRACE */
741
742 void trace_last_func_repeats(struct trace_array *tr,
743 struct trace_func_repeats *last_info,
744 unsigned int trace_ctx);
745
746 extern u64 ftrace_now(int cpu);
747
748 extern void trace_find_cmdline(int pid, char comm[]);
749 extern int trace_find_tgid(int pid);
750 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
751
752 #ifdef CONFIG_DYNAMIC_FTRACE
753 extern unsigned long ftrace_update_tot_cnt;
754 extern unsigned long ftrace_number_of_pages;
755 extern unsigned long ftrace_number_of_groups;
756 void ftrace_init_trace_array(struct trace_array *tr);
757 #else
ftrace_init_trace_array(struct trace_array * tr)758 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
759 #endif
760 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
761 extern int DYN_FTRACE_TEST_NAME(void);
762 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
763 extern int DYN_FTRACE_TEST_NAME2(void);
764
765 extern bool ring_buffer_expanded;
766 extern bool tracing_selftest_disabled;
767
768 #ifdef CONFIG_FTRACE_STARTUP_TEST
769 extern void __init disable_tracing_selftest(const char *reason);
770
771 extern int trace_selftest_startup_function(struct tracer *trace,
772 struct trace_array *tr);
773 extern int trace_selftest_startup_function_graph(struct tracer *trace,
774 struct trace_array *tr);
775 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
776 struct trace_array *tr);
777 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
778 struct trace_array *tr);
779 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
780 struct trace_array *tr);
781 extern int trace_selftest_startup_wakeup(struct tracer *trace,
782 struct trace_array *tr);
783 extern int trace_selftest_startup_nop(struct tracer *trace,
784 struct trace_array *tr);
785 extern int trace_selftest_startup_branch(struct tracer *trace,
786 struct trace_array *tr);
787 /*
788 * Tracer data references selftest functions that only occur
789 * on boot up. These can be __init functions. Thus, when selftests
790 * are enabled, then the tracers need to reference __init functions.
791 */
792 #define __tracer_data __refdata
793 #else
disable_tracing_selftest(const char * reason)794 static inline void __init disable_tracing_selftest(const char *reason)
795 {
796 }
797 /* Tracers are seldom changed. Optimize when selftests are disabled. */
798 #define __tracer_data __read_mostly
799 #endif /* CONFIG_FTRACE_STARTUP_TEST */
800
801 extern void *head_page(struct trace_array_cpu *data);
802 extern unsigned long long ns2usecs(u64 nsec);
803 extern int
804 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
805 extern int
806 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
807 extern int
808 trace_array_vprintk(struct trace_array *tr,
809 unsigned long ip, const char *fmt, va_list args);
810 int trace_array_printk_buf(struct trace_buffer *buffer,
811 unsigned long ip, const char *fmt, ...);
812 void trace_printk_seq(struct trace_seq *s);
813 enum print_line_t print_trace_line(struct trace_iterator *iter);
814
815 extern char trace_find_mark(unsigned long long duration);
816
817 struct ftrace_hash;
818
819 struct ftrace_mod_load {
820 struct list_head list;
821 char *func;
822 char *module;
823 int enable;
824 };
825
826 enum {
827 FTRACE_HASH_FL_MOD = (1 << 0),
828 };
829
830 struct ftrace_hash {
831 unsigned long size_bits;
832 struct hlist_head *buckets;
833 unsigned long count;
834 unsigned long flags;
835 struct rcu_head rcu;
836 };
837
838 struct ftrace_func_entry *
839 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
840
ftrace_hash_empty(struct ftrace_hash * hash)841 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
842 {
843 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
844 }
845
846 /* Standard output formatting function used for function return traces */
847 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
848
849 /* Flag options */
850 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
851 #define TRACE_GRAPH_PRINT_CPU 0x2
852 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
853 #define TRACE_GRAPH_PRINT_PROC 0x8
854 #define TRACE_GRAPH_PRINT_DURATION 0x10
855 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
856 #define TRACE_GRAPH_PRINT_REL_TIME 0x40
857 #define TRACE_GRAPH_PRINT_IRQS 0x80
858 #define TRACE_GRAPH_PRINT_TAIL 0x100
859 #define TRACE_GRAPH_SLEEP_TIME 0x200
860 #define TRACE_GRAPH_GRAPH_TIME 0x400
861 #define TRACE_GRAPH_PRINT_RETVAL 0x800
862 #define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000
863 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
864 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
865
866 extern void ftrace_graph_sleep_time_control(bool enable);
867
868 #ifdef CONFIG_FUNCTION_PROFILER
869 extern void ftrace_graph_graph_time_control(bool enable);
870 #else
ftrace_graph_graph_time_control(bool enable)871 static inline void ftrace_graph_graph_time_control(bool enable) { }
872 #endif
873
874 extern enum print_line_t
875 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
876 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
877 extern void
878 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
879 extern void graph_trace_open(struct trace_iterator *iter);
880 extern void graph_trace_close(struct trace_iterator *iter);
881 extern int __trace_graph_entry(struct trace_array *tr,
882 struct ftrace_graph_ent *trace,
883 unsigned int trace_ctx);
884 extern void __trace_graph_return(struct trace_array *tr,
885 struct ftrace_graph_ret *trace,
886 unsigned int trace_ctx);
887
888 #ifdef CONFIG_DYNAMIC_FTRACE
889 extern struct ftrace_hash __rcu *ftrace_graph_hash;
890 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
891
ftrace_graph_addr(struct ftrace_graph_ent * trace)892 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
893 {
894 unsigned long addr = trace->func;
895 int ret = 0;
896 struct ftrace_hash *hash;
897
898 preempt_disable_notrace();
899
900 /*
901 * Have to open code "rcu_dereference_sched()" because the
902 * function graph tracer can be called when RCU is not
903 * "watching".
904 * Protected with schedule_on_each_cpu(ftrace_sync)
905 */
906 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
907
908 if (ftrace_hash_empty(hash)) {
909 ret = 1;
910 goto out;
911 }
912
913 if (ftrace_lookup_ip(hash, addr)) {
914
915 /*
916 * This needs to be cleared on the return functions
917 * when the depth is zero.
918 */
919 trace_recursion_set(TRACE_GRAPH_BIT);
920 trace_recursion_set_depth(trace->depth);
921
922 /*
923 * If no irqs are to be traced, but a set_graph_function
924 * is set, and called by an interrupt handler, we still
925 * want to trace it.
926 */
927 if (in_hardirq())
928 trace_recursion_set(TRACE_IRQ_BIT);
929 else
930 trace_recursion_clear(TRACE_IRQ_BIT);
931 ret = 1;
932 }
933
934 out:
935 preempt_enable_notrace();
936 return ret;
937 }
938
ftrace_graph_addr_finish(struct ftrace_graph_ret * trace)939 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
940 {
941 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
942 trace->depth == trace_recursion_depth())
943 trace_recursion_clear(TRACE_GRAPH_BIT);
944 }
945
ftrace_graph_notrace_addr(unsigned long addr)946 static inline int ftrace_graph_notrace_addr(unsigned long addr)
947 {
948 int ret = 0;
949 struct ftrace_hash *notrace_hash;
950
951 preempt_disable_notrace();
952
953 /*
954 * Have to open code "rcu_dereference_sched()" because the
955 * function graph tracer can be called when RCU is not
956 * "watching".
957 * Protected with schedule_on_each_cpu(ftrace_sync)
958 */
959 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
960 !preemptible());
961
962 if (ftrace_lookup_ip(notrace_hash, addr))
963 ret = 1;
964
965 preempt_enable_notrace();
966 return ret;
967 }
968 #else
ftrace_graph_addr(struct ftrace_graph_ent * trace)969 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
970 {
971 return 1;
972 }
973
ftrace_graph_notrace_addr(unsigned long addr)974 static inline int ftrace_graph_notrace_addr(unsigned long addr)
975 {
976 return 0;
977 }
ftrace_graph_addr_finish(struct ftrace_graph_ret * trace)978 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
979 { }
980 #endif /* CONFIG_DYNAMIC_FTRACE */
981
982 extern unsigned int fgraph_max_depth;
983
ftrace_graph_ignore_func(struct ftrace_graph_ent * trace)984 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
985 {
986 /* trace it when it is-nested-in or is a function enabled. */
987 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
988 ftrace_graph_addr(trace)) ||
989 (trace->depth < 0) ||
990 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
991 }
992
993 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
994 static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)995 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
996 {
997 return TRACE_TYPE_UNHANDLED;
998 }
999 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1000
1001 extern struct list_head ftrace_pids;
1002
1003 #ifdef CONFIG_FUNCTION_TRACER
1004
1005 #define FTRACE_PID_IGNORE -1
1006 #define FTRACE_PID_TRACE -2
1007
1008 struct ftrace_func_command {
1009 struct list_head list;
1010 char *name;
1011 int (*func)(struct trace_array *tr,
1012 struct ftrace_hash *hash,
1013 char *func, char *cmd,
1014 char *params, int enable);
1015 };
1016 extern bool ftrace_filter_param __initdata;
ftrace_trace_task(struct trace_array * tr)1017 static inline int ftrace_trace_task(struct trace_array *tr)
1018 {
1019 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1020 FTRACE_PID_IGNORE;
1021 }
1022 extern int ftrace_is_dead(void);
1023 int ftrace_create_function_files(struct trace_array *tr,
1024 struct dentry *parent);
1025 void ftrace_destroy_function_files(struct trace_array *tr);
1026 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1027 void ftrace_free_ftrace_ops(struct trace_array *tr);
1028 void ftrace_init_global_array_ops(struct trace_array *tr);
1029 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1030 void ftrace_reset_array_ops(struct trace_array *tr);
1031 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1032 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1033 struct dentry *d_tracer);
1034 void ftrace_clear_pids(struct trace_array *tr);
1035 int init_function_trace(void);
1036 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1037 #else
ftrace_trace_task(struct trace_array * tr)1038 static inline int ftrace_trace_task(struct trace_array *tr)
1039 {
1040 return 1;
1041 }
ftrace_is_dead(void)1042 static inline int ftrace_is_dead(void) { return 0; }
1043 static inline int
ftrace_create_function_files(struct trace_array * tr,struct dentry * parent)1044 ftrace_create_function_files(struct trace_array *tr,
1045 struct dentry *parent)
1046 {
1047 return 0;
1048 }
ftrace_allocate_ftrace_ops(struct trace_array * tr)1049 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1050 {
1051 return 0;
1052 }
ftrace_free_ftrace_ops(struct trace_array * tr)1053 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
ftrace_destroy_function_files(struct trace_array * tr)1054 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1055 static inline __init void
ftrace_init_global_array_ops(struct trace_array * tr)1056 ftrace_init_global_array_ops(struct trace_array *tr) { }
ftrace_reset_array_ops(struct trace_array * tr)1057 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
ftrace_init_tracefs(struct trace_array * tr,struct dentry * d)1058 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
ftrace_init_tracefs_toplevel(struct trace_array * tr,struct dentry * d)1059 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
ftrace_clear_pids(struct trace_array * tr)1060 static inline void ftrace_clear_pids(struct trace_array *tr) { }
init_function_trace(void)1061 static inline int init_function_trace(void) { return 0; }
ftrace_pid_follow_fork(struct trace_array * tr,bool enable)1062 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1063 /* ftace_func_t type is not defined, use macro instead of static inline */
1064 #define ftrace_init_array_ops(tr, func) do { } while (0)
1065 #endif /* CONFIG_FUNCTION_TRACER */
1066
1067 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1068
1069 struct ftrace_probe_ops {
1070 void (*func)(unsigned long ip,
1071 unsigned long parent_ip,
1072 struct trace_array *tr,
1073 struct ftrace_probe_ops *ops,
1074 void *data);
1075 int (*init)(struct ftrace_probe_ops *ops,
1076 struct trace_array *tr,
1077 unsigned long ip, void *init_data,
1078 void **data);
1079 void (*free)(struct ftrace_probe_ops *ops,
1080 struct trace_array *tr,
1081 unsigned long ip, void *data);
1082 int (*print)(struct seq_file *m,
1083 unsigned long ip,
1084 struct ftrace_probe_ops *ops,
1085 void *data);
1086 };
1087
1088 struct ftrace_func_mapper;
1089 typedef int (*ftrace_mapper_func)(void *data);
1090
1091 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1092 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1093 unsigned long ip);
1094 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1095 unsigned long ip, void *data);
1096 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1097 unsigned long ip);
1098 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1099 ftrace_mapper_func free_func);
1100
1101 extern int
1102 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1103 struct ftrace_probe_ops *ops, void *data);
1104 extern int
1105 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1106 struct ftrace_probe_ops *ops);
1107 extern void clear_ftrace_function_probes(struct trace_array *tr);
1108
1109 int register_ftrace_command(struct ftrace_func_command *cmd);
1110 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1111
1112 void ftrace_create_filter_files(struct ftrace_ops *ops,
1113 struct dentry *parent);
1114 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1115
1116 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1117 int len, int reset);
1118 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1119 int len, int reset);
1120 #else
1121 struct ftrace_func_command;
1122
register_ftrace_command(struct ftrace_func_command * cmd)1123 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1124 {
1125 return -EINVAL;
1126 }
unregister_ftrace_command(char * cmd_name)1127 static inline __init int unregister_ftrace_command(char *cmd_name)
1128 {
1129 return -EINVAL;
1130 }
clear_ftrace_function_probes(struct trace_array * tr)1131 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1132 {
1133 }
1134
1135 /*
1136 * The ops parameter passed in is usually undefined.
1137 * This must be a macro.
1138 */
1139 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1140 #define ftrace_destroy_filter_files(ops) do { } while (0)
1141 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1142
1143 bool ftrace_event_is_function(struct trace_event_call *call);
1144
1145 /*
1146 * struct trace_parser - servers for reading the user input separated by spaces
1147 * @cont: set if the input is not complete - no final space char was found
1148 * @buffer: holds the parsed user input
1149 * @idx: user input length
1150 * @size: buffer size
1151 */
1152 struct trace_parser {
1153 bool cont;
1154 char *buffer;
1155 unsigned idx;
1156 unsigned size;
1157 };
1158
trace_parser_loaded(struct trace_parser * parser)1159 static inline bool trace_parser_loaded(struct trace_parser *parser)
1160 {
1161 return (parser->idx != 0);
1162 }
1163
trace_parser_cont(struct trace_parser * parser)1164 static inline bool trace_parser_cont(struct trace_parser *parser)
1165 {
1166 return parser->cont;
1167 }
1168
trace_parser_clear(struct trace_parser * parser)1169 static inline void trace_parser_clear(struct trace_parser *parser)
1170 {
1171 parser->cont = false;
1172 parser->idx = 0;
1173 }
1174
1175 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1176 extern void trace_parser_put(struct trace_parser *parser);
1177 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1178 size_t cnt, loff_t *ppos);
1179
1180 /*
1181 * Only create function graph options if function graph is configured.
1182 */
1183 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1184 # define FGRAPH_FLAGS \
1185 C(DISPLAY_GRAPH, "display-graph"),
1186 #else
1187 # define FGRAPH_FLAGS
1188 #endif
1189
1190 #ifdef CONFIG_BRANCH_TRACER
1191 # define BRANCH_FLAGS \
1192 C(BRANCH, "branch"),
1193 #else
1194 # define BRANCH_FLAGS
1195 #endif
1196
1197 #ifdef CONFIG_FUNCTION_TRACER
1198 # define FUNCTION_FLAGS \
1199 C(FUNCTION, "function-trace"), \
1200 C(FUNC_FORK, "function-fork"),
1201 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1202 #else
1203 # define FUNCTION_FLAGS
1204 # define FUNCTION_DEFAULT_FLAGS 0UL
1205 # define TRACE_ITER_FUNC_FORK 0UL
1206 #endif
1207
1208 #ifdef CONFIG_STACKTRACE
1209 # define STACK_FLAGS \
1210 C(STACKTRACE, "stacktrace"),
1211 #else
1212 # define STACK_FLAGS
1213 #endif
1214
1215 /*
1216 * trace_iterator_flags is an enumeration that defines bit
1217 * positions into trace_flags that controls the output.
1218 *
1219 * NOTE: These bits must match the trace_options array in
1220 * trace.c (this macro guarantees it).
1221 */
1222 #define TRACE_FLAGS \
1223 C(PRINT_PARENT, "print-parent"), \
1224 C(SYM_OFFSET, "sym-offset"), \
1225 C(SYM_ADDR, "sym-addr"), \
1226 C(VERBOSE, "verbose"), \
1227 C(RAW, "raw"), \
1228 C(HEX, "hex"), \
1229 C(BIN, "bin"), \
1230 C(BLOCK, "block"), \
1231 C(FIELDS, "fields"), \
1232 C(PRINTK, "trace_printk"), \
1233 C(ANNOTATE, "annotate"), \
1234 C(USERSTACKTRACE, "userstacktrace"), \
1235 C(SYM_USEROBJ, "sym-userobj"), \
1236 C(PRINTK_MSGONLY, "printk-msg-only"), \
1237 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1238 C(LATENCY_FMT, "latency-format"), \
1239 C(RECORD_CMD, "record-cmd"), \
1240 C(RECORD_TGID, "record-tgid"), \
1241 C(OVERWRITE, "overwrite"), \
1242 C(STOP_ON_FREE, "disable_on_free"), \
1243 C(IRQ_INFO, "irq-info"), \
1244 C(MARKERS, "markers"), \
1245 C(EVENT_FORK, "event-fork"), \
1246 C(PAUSE_ON_TRACE, "pause-on-trace"), \
1247 C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \
1248 FUNCTION_FLAGS \
1249 FGRAPH_FLAGS \
1250 STACK_FLAGS \
1251 BRANCH_FLAGS
1252
1253 /*
1254 * By defining C, we can make TRACE_FLAGS a list of bit names
1255 * that will define the bits for the flag masks.
1256 */
1257 #undef C
1258 #define C(a, b) TRACE_ITER_##a##_BIT
1259
1260 enum trace_iterator_bits {
1261 TRACE_FLAGS
1262 /* Make sure we don't go more than we have bits for */
1263 TRACE_ITER_LAST_BIT
1264 };
1265
1266 /*
1267 * By redefining C, we can make TRACE_FLAGS a list of masks that
1268 * use the bits as defined above.
1269 */
1270 #undef C
1271 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1272
1273 enum trace_iterator_flags { TRACE_FLAGS };
1274
1275 /*
1276 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1277 * control the output of kernel symbols.
1278 */
1279 #define TRACE_ITER_SYM_MASK \
1280 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1281
1282 extern struct tracer nop_trace;
1283
1284 #ifdef CONFIG_BRANCH_TRACER
1285 extern int enable_branch_tracing(struct trace_array *tr);
1286 extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)1287 static inline int trace_branch_enable(struct trace_array *tr)
1288 {
1289 if (tr->trace_flags & TRACE_ITER_BRANCH)
1290 return enable_branch_tracing(tr);
1291 return 0;
1292 }
trace_branch_disable(void)1293 static inline void trace_branch_disable(void)
1294 {
1295 /* due to races, always disable */
1296 disable_branch_tracing();
1297 }
1298 #else
trace_branch_enable(struct trace_array * tr)1299 static inline int trace_branch_enable(struct trace_array *tr)
1300 {
1301 return 0;
1302 }
trace_branch_disable(void)1303 static inline void trace_branch_disable(void)
1304 {
1305 }
1306 #endif /* CONFIG_BRANCH_TRACER */
1307
1308 /* set ring buffers to default size if not already done so */
1309 int tracing_update_buffers(void);
1310
1311 union trace_synth_field {
1312 u8 as_u8;
1313 u16 as_u16;
1314 u32 as_u32;
1315 u64 as_u64;
1316 struct trace_dynamic_info as_dynamic;
1317 };
1318
1319 struct ftrace_event_field {
1320 struct list_head link;
1321 const char *name;
1322 const char *type;
1323 int filter_type;
1324 int offset;
1325 int size;
1326 int is_signed;
1327 int len;
1328 };
1329
1330 struct prog_entry;
1331
1332 struct event_filter {
1333 struct prog_entry __rcu *prog;
1334 char *filter_string;
1335 };
1336
1337 struct event_subsystem {
1338 struct list_head list;
1339 const char *name;
1340 struct event_filter *filter;
1341 int ref_count;
1342 };
1343
1344 struct trace_subsystem_dir {
1345 struct list_head list;
1346 struct event_subsystem *subsystem;
1347 struct trace_array *tr;
1348 struct eventfs_inode *ei;
1349 int ref_count;
1350 int nr_events;
1351 };
1352
1353 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1354 struct trace_buffer *buffer,
1355 struct ring_buffer_event *event);
1356
1357 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1358 struct trace_buffer *buffer,
1359 struct ring_buffer_event *event,
1360 unsigned int trcace_ctx,
1361 struct pt_regs *regs);
1362
trace_buffer_unlock_commit(struct trace_array * tr,struct trace_buffer * buffer,struct ring_buffer_event * event,unsigned int trace_ctx)1363 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1364 struct trace_buffer *buffer,
1365 struct ring_buffer_event *event,
1366 unsigned int trace_ctx)
1367 {
1368 trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1369 }
1370
1371 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1372 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1373 void trace_buffered_event_disable(void);
1374 void trace_buffered_event_enable(void);
1375
1376 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1377
1378 static inline void
__trace_event_discard_commit(struct trace_buffer * buffer,struct ring_buffer_event * event)1379 __trace_event_discard_commit(struct trace_buffer *buffer,
1380 struct ring_buffer_event *event)
1381 {
1382 if (this_cpu_read(trace_buffered_event) == event) {
1383 /* Simply release the temp buffer and enable preemption */
1384 this_cpu_dec(trace_buffered_event_cnt);
1385 preempt_enable_notrace();
1386 return;
1387 }
1388 /* ring_buffer_discard_commit() enables preemption */
1389 ring_buffer_discard_commit(buffer, event);
1390 }
1391
1392 /*
1393 * Helper function for event_trigger_unlock_commit{_regs}().
1394 * If there are event triggers attached to this event that requires
1395 * filtering against its fields, then they will be called as the
1396 * entry already holds the field information of the current event.
1397 *
1398 * It also checks if the event should be discarded or not.
1399 * It is to be discarded if the event is soft disabled and the
1400 * event was only recorded to process triggers, or if the event
1401 * filter is active and this event did not match the filters.
1402 *
1403 * Returns true if the event is discarded, false otherwise.
1404 */
1405 static inline bool
__event_trigger_test_discard(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,enum event_trigger_type * tt)1406 __event_trigger_test_discard(struct trace_event_file *file,
1407 struct trace_buffer *buffer,
1408 struct ring_buffer_event *event,
1409 void *entry,
1410 enum event_trigger_type *tt)
1411 {
1412 unsigned long eflags = file->flags;
1413
1414 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1415 *tt = event_triggers_call(file, buffer, entry, event);
1416
1417 if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1418 EVENT_FILE_FL_FILTERED |
1419 EVENT_FILE_FL_PID_FILTER))))
1420 return false;
1421
1422 if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1423 goto discard;
1424
1425 if (file->flags & EVENT_FILE_FL_FILTERED &&
1426 !filter_match_preds(file->filter, entry))
1427 goto discard;
1428
1429 if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1430 trace_event_ignore_this_pid(file))
1431 goto discard;
1432
1433 return false;
1434 discard:
1435 __trace_event_discard_commit(buffer, event);
1436 return true;
1437 }
1438
1439 /**
1440 * event_trigger_unlock_commit - handle triggers and finish event commit
1441 * @file: The file pointer associated with the event
1442 * @buffer: The ring buffer that the event is being written to
1443 * @event: The event meta data in the ring buffer
1444 * @entry: The event itself
1445 * @trace_ctx: The tracing context flags.
1446 *
1447 * This is a helper function to handle triggers that require data
1448 * from the event itself. It also tests the event against filters and
1449 * if the event is soft disabled and should be discarded.
1450 */
1451 static inline void
event_trigger_unlock_commit(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,unsigned int trace_ctx)1452 event_trigger_unlock_commit(struct trace_event_file *file,
1453 struct trace_buffer *buffer,
1454 struct ring_buffer_event *event,
1455 void *entry, unsigned int trace_ctx)
1456 {
1457 enum event_trigger_type tt = ETT_NONE;
1458
1459 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1460 trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1461
1462 if (tt)
1463 event_triggers_post_call(file, tt);
1464 }
1465
1466 #define FILTER_PRED_INVALID ((unsigned short)-1)
1467 #define FILTER_PRED_IS_RIGHT (1 << 15)
1468 #define FILTER_PRED_FOLD (1 << 15)
1469
1470 /*
1471 * The max preds is the size of unsigned short with
1472 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1473 * and FOLD flags. The other is reserved.
1474 *
1475 * 2^14 preds is way more than enough.
1476 */
1477 #define MAX_FILTER_PRED 16384
1478
1479 struct filter_pred;
1480 struct regex;
1481
1482 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1483
1484 enum regex_type {
1485 MATCH_FULL = 0,
1486 MATCH_FRONT_ONLY,
1487 MATCH_MIDDLE_ONLY,
1488 MATCH_END_ONLY,
1489 MATCH_GLOB,
1490 MATCH_INDEX,
1491 };
1492
1493 struct regex {
1494 char pattern[MAX_FILTER_STR_VAL];
1495 int len;
1496 int field_len;
1497 regex_match_func match;
1498 };
1499
is_string_field(struct ftrace_event_field * field)1500 static inline bool is_string_field(struct ftrace_event_field *field)
1501 {
1502 return field->filter_type == FILTER_DYN_STRING ||
1503 field->filter_type == FILTER_RDYN_STRING ||
1504 field->filter_type == FILTER_STATIC_STRING ||
1505 field->filter_type == FILTER_PTR_STRING ||
1506 field->filter_type == FILTER_COMM;
1507 }
1508
is_function_field(struct ftrace_event_field * field)1509 static inline bool is_function_field(struct ftrace_event_field *field)
1510 {
1511 return field->filter_type == FILTER_TRACE_FN;
1512 }
1513
1514 extern enum regex_type
1515 filter_parse_regex(char *buff, int len, char **search, int *not);
1516 extern void print_event_filter(struct trace_event_file *file,
1517 struct trace_seq *s);
1518 extern int apply_event_filter(struct trace_event_file *file,
1519 char *filter_string);
1520 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1521 char *filter_string);
1522 extern void print_subsystem_event_filter(struct event_subsystem *system,
1523 struct trace_seq *s);
1524 extern int filter_assign_type(const char *type);
1525 extern int create_event_filter(struct trace_array *tr,
1526 struct trace_event_call *call,
1527 char *filter_str, bool set_str,
1528 struct event_filter **filterp);
1529 extern void free_event_filter(struct event_filter *filter);
1530
1531 struct ftrace_event_field *
1532 trace_find_event_field(struct trace_event_call *call, char *name);
1533
1534 extern void trace_event_enable_cmd_record(bool enable);
1535 extern void trace_event_enable_tgid_record(bool enable);
1536
1537 extern int event_trace_init(void);
1538 extern int init_events(void);
1539 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1540 extern int event_trace_del_tracer(struct trace_array *tr);
1541 extern void __trace_early_add_events(struct trace_array *tr);
1542
1543 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1544 const char *system,
1545 const char *event);
1546 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1547 const char *system,
1548 const char *event);
1549
event_file_data(struct file * filp)1550 static inline void *event_file_data(struct file *filp)
1551 {
1552 return READ_ONCE(file_inode(filp)->i_private);
1553 }
1554
1555 extern struct mutex event_mutex;
1556 extern struct list_head ftrace_events;
1557
1558 /*
1559 * When the trace_event_file is the filp->i_private pointer,
1560 * it must be taken under the event_mutex lock, and then checked
1561 * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1562 * data pointed to by the trace_event_file can not be trusted.
1563 *
1564 * Use the event_file_file() to access the trace_event_file from
1565 * the filp the first time under the event_mutex and check for
1566 * NULL. If it is needed to be retrieved again and the event_mutex
1567 * is still held, then the event_file_data() can be used and it
1568 * is guaranteed to be valid.
1569 */
event_file_file(struct file * filp)1570 static inline struct trace_event_file *event_file_file(struct file *filp)
1571 {
1572 struct trace_event_file *file;
1573
1574 lockdep_assert_held(&event_mutex);
1575 file = READ_ONCE(file_inode(filp)->i_private);
1576 if (!file || file->flags & EVENT_FILE_FL_FREED)
1577 return NULL;
1578 return file;
1579 }
1580
1581 extern const struct file_operations event_trigger_fops;
1582 extern const struct file_operations event_hist_fops;
1583 extern const struct file_operations event_hist_debug_fops;
1584 extern const struct file_operations event_inject_fops;
1585
1586 #ifdef CONFIG_HIST_TRIGGERS
1587 extern int register_trigger_hist_cmd(void);
1588 extern int register_trigger_hist_enable_disable_cmds(void);
1589 #else
register_trigger_hist_cmd(void)1590 static inline int register_trigger_hist_cmd(void) { return 0; }
register_trigger_hist_enable_disable_cmds(void)1591 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1592 #endif
1593
1594 extern int register_trigger_cmds(void);
1595 extern void clear_event_triggers(struct trace_array *tr);
1596
1597 enum {
1598 EVENT_TRIGGER_FL_PROBE = BIT(0),
1599 };
1600
1601 struct event_trigger_data {
1602 unsigned long count;
1603 int ref;
1604 int flags;
1605 struct event_trigger_ops *ops;
1606 struct event_command *cmd_ops;
1607 struct event_filter __rcu *filter;
1608 char *filter_str;
1609 void *private_data;
1610 bool paused;
1611 bool paused_tmp;
1612 struct list_head list;
1613 char *name;
1614 struct list_head named_list;
1615 struct event_trigger_data *named_data;
1616 };
1617
1618 /* Avoid typos */
1619 #define ENABLE_EVENT_STR "enable_event"
1620 #define DISABLE_EVENT_STR "disable_event"
1621 #define ENABLE_HIST_STR "enable_hist"
1622 #define DISABLE_HIST_STR "disable_hist"
1623
1624 struct enable_trigger_data {
1625 struct trace_event_file *file;
1626 bool enable;
1627 bool hist;
1628 };
1629
1630 extern int event_enable_trigger_print(struct seq_file *m,
1631 struct event_trigger_data *data);
1632 extern void event_enable_trigger_free(struct event_trigger_data *data);
1633 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1634 struct trace_event_file *file,
1635 char *glob, char *cmd,
1636 char *param_and_filter);
1637 extern int event_enable_register_trigger(char *glob,
1638 struct event_trigger_data *data,
1639 struct trace_event_file *file);
1640 extern void event_enable_unregister_trigger(char *glob,
1641 struct event_trigger_data *test,
1642 struct trace_event_file *file);
1643 extern void trigger_data_free(struct event_trigger_data *data);
1644 extern int event_trigger_init(struct event_trigger_data *data);
1645 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1646 int trigger_enable);
1647 extern void update_cond_flag(struct trace_event_file *file);
1648 extern int set_trigger_filter(char *filter_str,
1649 struct event_trigger_data *trigger_data,
1650 struct trace_event_file *file);
1651 extern struct event_trigger_data *find_named_trigger(const char *name);
1652 extern bool is_named_trigger(struct event_trigger_data *test);
1653 extern int save_named_trigger(const char *name,
1654 struct event_trigger_data *data);
1655 extern void del_named_trigger(struct event_trigger_data *data);
1656 extern void pause_named_trigger(struct event_trigger_data *data);
1657 extern void unpause_named_trigger(struct event_trigger_data *data);
1658 extern void set_named_trigger_data(struct event_trigger_data *data,
1659 struct event_trigger_data *named_data);
1660 extern struct event_trigger_data *
1661 get_named_trigger_data(struct event_trigger_data *data);
1662 extern int register_event_command(struct event_command *cmd);
1663 extern int unregister_event_command(struct event_command *cmd);
1664 extern int register_trigger_hist_enable_disable_cmds(void);
1665 extern bool event_trigger_check_remove(const char *glob);
1666 extern bool event_trigger_empty_param(const char *param);
1667 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1668 char **filter, bool param_required);
1669 extern struct event_trigger_data *
1670 event_trigger_alloc(struct event_command *cmd_ops,
1671 char *cmd,
1672 char *param,
1673 void *private_data);
1674 extern int event_trigger_parse_num(char *trigger,
1675 struct event_trigger_data *trigger_data);
1676 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1677 struct trace_event_file *file,
1678 char *param,
1679 struct event_trigger_data *trigger_data);
1680 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1681 struct event_trigger_data *trigger_data);
1682 extern int event_trigger_register(struct event_command *cmd_ops,
1683 struct trace_event_file *file,
1684 char *glob,
1685 struct event_trigger_data *trigger_data);
1686 extern void event_trigger_unregister(struct event_command *cmd_ops,
1687 struct trace_event_file *file,
1688 char *glob,
1689 struct event_trigger_data *trigger_data);
1690
1691 extern void event_file_get(struct trace_event_file *file);
1692 extern void event_file_put(struct trace_event_file *file);
1693
1694 /**
1695 * struct event_trigger_ops - callbacks for trace event triggers
1696 *
1697 * The methods in this structure provide per-event trigger hooks for
1698 * various trigger operations.
1699 *
1700 * The @init and @free methods are used during trigger setup and
1701 * teardown, typically called from an event_command's @parse()
1702 * function implementation.
1703 *
1704 * The @print method is used to print the trigger spec.
1705 *
1706 * The @trigger method is the function that actually implements the
1707 * trigger and is called in the context of the triggering event
1708 * whenever that event occurs.
1709 *
1710 * All the methods below, except for @init() and @free(), must be
1711 * implemented.
1712 *
1713 * @trigger: The trigger 'probe' function called when the triggering
1714 * event occurs. The data passed into this callback is the data
1715 * that was supplied to the event_command @reg() function that
1716 * registered the trigger (see struct event_command) along with
1717 * the trace record, rec.
1718 *
1719 * @init: An optional initialization function called for the trigger
1720 * when the trigger is registered (via the event_command reg()
1721 * function). This can be used to perform per-trigger
1722 * initialization such as incrementing a per-trigger reference
1723 * count, for instance. This is usually implemented by the
1724 * generic utility function @event_trigger_init() (see
1725 * trace_event_triggers.c).
1726 *
1727 * @free: An optional de-initialization function called for the
1728 * trigger when the trigger is unregistered (via the
1729 * event_command @reg() function). This can be used to perform
1730 * per-trigger de-initialization such as decrementing a
1731 * per-trigger reference count and freeing corresponding trigger
1732 * data, for instance. This is usually implemented by the
1733 * generic utility function @event_trigger_free() (see
1734 * trace_event_triggers.c).
1735 *
1736 * @print: The callback function invoked to have the trigger print
1737 * itself. This is usually implemented by a wrapper function
1738 * that calls the generic utility function @event_trigger_print()
1739 * (see trace_event_triggers.c).
1740 */
1741 struct event_trigger_ops {
1742 void (*trigger)(struct event_trigger_data *data,
1743 struct trace_buffer *buffer,
1744 void *rec,
1745 struct ring_buffer_event *rbe);
1746 int (*init)(struct event_trigger_data *data);
1747 void (*free)(struct event_trigger_data *data);
1748 int (*print)(struct seq_file *m,
1749 struct event_trigger_data *data);
1750 };
1751
1752 /**
1753 * struct event_command - callbacks and data members for event commands
1754 *
1755 * Event commands are invoked by users by writing the command name
1756 * into the 'trigger' file associated with a trace event. The
1757 * parameters associated with a specific invocation of an event
1758 * command are used to create an event trigger instance, which is
1759 * added to the list of trigger instances associated with that trace
1760 * event. When the event is hit, the set of triggers associated with
1761 * that event is invoked.
1762 *
1763 * The data members in this structure provide per-event command data
1764 * for various event commands.
1765 *
1766 * All the data members below, except for @post_trigger, must be set
1767 * for each event command.
1768 *
1769 * @name: The unique name that identifies the event command. This is
1770 * the name used when setting triggers via trigger files.
1771 *
1772 * @trigger_type: A unique id that identifies the event command
1773 * 'type'. This value has two purposes, the first to ensure that
1774 * only one trigger of the same type can be set at a given time
1775 * for a particular event e.g. it doesn't make sense to have both
1776 * a traceon and traceoff trigger attached to a single event at
1777 * the same time, so traceon and traceoff have the same type
1778 * though they have different names. The @trigger_type value is
1779 * also used as a bit value for deferring the actual trigger
1780 * action until after the current event is finished. Some
1781 * commands need to do this if they themselves log to the trace
1782 * buffer (see the @post_trigger() member below). @trigger_type
1783 * values are defined by adding new values to the trigger_type
1784 * enum in include/linux/trace_events.h.
1785 *
1786 * @flags: See the enum event_command_flags below.
1787 *
1788 * All the methods below, except for @set_filter() and @unreg_all(),
1789 * must be implemented.
1790 *
1791 * @parse: The callback function responsible for parsing and
1792 * registering the trigger written to the 'trigger' file by the
1793 * user. It allocates the trigger instance and registers it with
1794 * the appropriate trace event. It makes use of the other
1795 * event_command callback functions to orchestrate this, and is
1796 * usually implemented by the generic utility function
1797 * @event_trigger_callback() (see trace_event_triggers.c).
1798 *
1799 * @reg: Adds the trigger to the list of triggers associated with the
1800 * event, and enables the event trigger itself, after
1801 * initializing it (via the event_trigger_ops @init() function).
1802 * This is also where commands can use the @trigger_type value to
1803 * make the decision as to whether or not multiple instances of
1804 * the trigger should be allowed. This is usually implemented by
1805 * the generic utility function @register_trigger() (see
1806 * trace_event_triggers.c).
1807 *
1808 * @unreg: Removes the trigger from the list of triggers associated
1809 * with the event, and disables the event trigger itself, after
1810 * initializing it (via the event_trigger_ops @free() function).
1811 * This is usually implemented by the generic utility function
1812 * @unregister_trigger() (see trace_event_triggers.c).
1813 *
1814 * @unreg_all: An optional function called to remove all the triggers
1815 * from the list of triggers associated with the event. Called
1816 * when a trigger file is opened in truncate mode.
1817 *
1818 * @set_filter: An optional function called to parse and set a filter
1819 * for the trigger. If no @set_filter() method is set for the
1820 * event command, filters set by the user for the command will be
1821 * ignored. This is usually implemented by the generic utility
1822 * function @set_trigger_filter() (see trace_event_triggers.c).
1823 *
1824 * @get_trigger_ops: The callback function invoked to retrieve the
1825 * event_trigger_ops implementation associated with the command.
1826 * This callback function allows a single event_command to
1827 * support multiple trigger implementations via different sets of
1828 * event_trigger_ops, depending on the value of the @param
1829 * string.
1830 */
1831 struct event_command {
1832 struct list_head list;
1833 char *name;
1834 enum event_trigger_type trigger_type;
1835 int flags;
1836 int (*parse)(struct event_command *cmd_ops,
1837 struct trace_event_file *file,
1838 char *glob, char *cmd,
1839 char *param_and_filter);
1840 int (*reg)(char *glob,
1841 struct event_trigger_data *data,
1842 struct trace_event_file *file);
1843 void (*unreg)(char *glob,
1844 struct event_trigger_data *data,
1845 struct trace_event_file *file);
1846 void (*unreg_all)(struct trace_event_file *file);
1847 int (*set_filter)(char *filter_str,
1848 struct event_trigger_data *data,
1849 struct trace_event_file *file);
1850 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1851 };
1852
1853 /**
1854 * enum event_command_flags - flags for struct event_command
1855 *
1856 * @POST_TRIGGER: A flag that says whether or not this command needs
1857 * to have its action delayed until after the current event has
1858 * been closed. Some triggers need to avoid being invoked while
1859 * an event is currently in the process of being logged, since
1860 * the trigger may itself log data into the trace buffer. Thus
1861 * we make sure the current event is committed before invoking
1862 * those triggers. To do that, the trigger invocation is split
1863 * in two - the first part checks the filter using the current
1864 * trace record; if a command has the @post_trigger flag set, it
1865 * sets a bit for itself in the return value, otherwise it
1866 * directly invokes the trigger. Once all commands have been
1867 * either invoked or set their return flag, the current record is
1868 * either committed or discarded. At that point, if any commands
1869 * have deferred their triggers, those commands are finally
1870 * invoked following the close of the current event. In other
1871 * words, if the event_trigger_ops @func() probe implementation
1872 * itself logs to the trace buffer, this flag should be set,
1873 * otherwise it can be left unspecified.
1874 *
1875 * @NEEDS_REC: A flag that says whether or not this command needs
1876 * access to the trace record in order to perform its function,
1877 * regardless of whether or not it has a filter associated with
1878 * it (filters make a trigger require access to the trace record
1879 * but are not always present).
1880 */
1881 enum event_command_flags {
1882 EVENT_CMD_FL_POST_TRIGGER = 1,
1883 EVENT_CMD_FL_NEEDS_REC = 2,
1884 };
1885
event_command_post_trigger(struct event_command * cmd_ops)1886 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1887 {
1888 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1889 }
1890
event_command_needs_rec(struct event_command * cmd_ops)1891 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1892 {
1893 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1894 }
1895
1896 extern int trace_event_enable_disable(struct trace_event_file *file,
1897 int enable, int soft_disable);
1898 extern int tracing_alloc_snapshot(void);
1899 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1900 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1901
1902 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1903 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1904
1905 extern const char *__start___trace_bprintk_fmt[];
1906 extern const char *__stop___trace_bprintk_fmt[];
1907
1908 extern const char *__start___tracepoint_str[];
1909 extern const char *__stop___tracepoint_str[];
1910
1911 void trace_printk_control(bool enabled);
1912 void trace_printk_start_comm(void);
1913 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1914 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1915
1916 /* Used from boot time tracer */
1917 extern int trace_set_options(struct trace_array *tr, char *option);
1918 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1919 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1920 unsigned long size, int cpu_id);
1921 extern int tracing_set_cpumask(struct trace_array *tr,
1922 cpumask_var_t tracing_cpumask_new);
1923
1924
1925 #define MAX_EVENT_NAME_LEN 64
1926
1927 extern ssize_t trace_parse_run_command(struct file *file,
1928 const char __user *buffer, size_t count, loff_t *ppos,
1929 int (*createfn)(const char *));
1930
1931 extern unsigned int err_pos(char *cmd, const char *str);
1932 extern void tracing_log_err(struct trace_array *tr,
1933 const char *loc, const char *cmd,
1934 const char **errs, u8 type, u16 pos);
1935
1936 /*
1937 * Normal trace_printk() and friends allocates special buffers
1938 * to do the manipulation, as well as saves the print formats
1939 * into sections to display. But the trace infrastructure wants
1940 * to use these without the added overhead at the price of being
1941 * a bit slower (used mainly for warnings, where we don't care
1942 * about performance). The internal_trace_puts() is for such
1943 * a purpose.
1944 */
1945 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1946
1947 #undef FTRACE_ENTRY
1948 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
1949 extern struct trace_event_call \
1950 __aligned(4) event_##call;
1951 #undef FTRACE_ENTRY_DUP
1952 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
1953 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1954 #undef FTRACE_ENTRY_PACKED
1955 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1956 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1957
1958 #include "trace_entries.h"
1959
1960 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1961 int perf_ftrace_event_register(struct trace_event_call *call,
1962 enum trace_reg type, void *data);
1963 #else
1964 #define perf_ftrace_event_register NULL
1965 #endif
1966
1967 #ifdef CONFIG_FTRACE_SYSCALLS
1968 void init_ftrace_syscalls(void);
1969 const char *get_syscall_name(int syscall);
1970 #else
init_ftrace_syscalls(void)1971 static inline void init_ftrace_syscalls(void) { }
get_syscall_name(int syscall)1972 static inline const char *get_syscall_name(int syscall)
1973 {
1974 return NULL;
1975 }
1976 #endif
1977
1978 #ifdef CONFIG_EVENT_TRACING
1979 void trace_event_init(void);
1980 void trace_event_eval_update(struct trace_eval_map **map, int len);
1981 /* Used from boot time tracer */
1982 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1983 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1984 #else
trace_event_init(void)1985 static inline void __init trace_event_init(void) { }
trace_event_eval_update(struct trace_eval_map ** map,int len)1986 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1987 #endif
1988
1989 #ifdef CONFIG_TRACER_SNAPSHOT
1990 void tracing_snapshot_instance(struct trace_array *tr);
1991 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1992 #else
tracing_snapshot_instance(struct trace_array * tr)1993 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
tracing_alloc_snapshot_instance(struct trace_array * tr)1994 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1995 {
1996 return 0;
1997 }
1998 #endif
1999
2000 #ifdef CONFIG_PREEMPT_TRACER
2001 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2002 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2003 #else
tracer_preempt_on(unsigned long a0,unsigned long a1)2004 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
tracer_preempt_off(unsigned long a0,unsigned long a1)2005 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2006 #endif
2007 #ifdef CONFIG_IRQSOFF_TRACER
2008 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2009 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2010 #else
tracer_hardirqs_on(unsigned long a0,unsigned long a1)2011 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
tracer_hardirqs_off(unsigned long a0,unsigned long a1)2012 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2013 #endif
2014
2015 /*
2016 * Reset the state of the trace_iterator so that it can read consumed data.
2017 * Normally, the trace_iterator is used for reading the data when it is not
2018 * consumed, and must retain state.
2019 */
trace_iterator_reset(struct trace_iterator * iter)2020 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2021 {
2022 memset_startat(iter, 0, seq);
2023 iter->pos = -1;
2024 }
2025
2026 /* Check the name is good for event/group/fields */
__is_good_name(const char * name,bool hash_ok)2027 static inline bool __is_good_name(const char *name, bool hash_ok)
2028 {
2029 if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2030 return false;
2031 while (*++name != '\0') {
2032 if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2033 (!hash_ok || *name != '-'))
2034 return false;
2035 }
2036 return true;
2037 }
2038
2039 /* Check the name is good for event/group/fields */
is_good_name(const char * name)2040 static inline bool is_good_name(const char *name)
2041 {
2042 return __is_good_name(name, false);
2043 }
2044
2045 /* Check the name is good for system */
is_good_system_name(const char * name)2046 static inline bool is_good_system_name(const char *name)
2047 {
2048 return __is_good_name(name, true);
2049 }
2050
2051 /* Convert certain expected symbols into '_' when generating event names */
sanitize_event_name(char * name)2052 static inline void sanitize_event_name(char *name)
2053 {
2054 while (*name++ != '\0')
2055 if (*name == ':' || *name == '.')
2056 *name = '_';
2057 }
2058
2059 /*
2060 * This is a generic way to read and write a u64 value from a file in tracefs.
2061 *
2062 * The value is stored on the variable pointed by *val. The value needs
2063 * to be at least *min and at most *max. The write is protected by an
2064 * existing *lock.
2065 */
2066 struct trace_min_max_param {
2067 struct mutex *lock;
2068 u64 *val;
2069 u64 *min;
2070 u64 *max;
2071 };
2072
2073 #define U64_STR_SIZE 24 /* 20 digits max */
2074
2075 extern const struct file_operations trace_min_max_fops;
2076
2077 #ifdef CONFIG_RV
2078 extern int rv_init_interface(void);
2079 #else
rv_init_interface(void)2080 static inline int rv_init_interface(void)
2081 {
2082 return 0;
2083 }
2084 #endif
2085
2086 #endif /* _LINUX_KERNEL_TRACE_H */
2087