projects/linux·blob v4.18 · refs

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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/hw_breakpoint.h>
15#include <linux/trace_seq.h>
16#include <linux/trace_events.h>
17#include <linux/compiler.h>
18#include <linux/trace_seq.h>
19#include <linux/glob.h>
20
21#ifdef CONFIG_FTRACE_SYSCALLS
22#include <asm/unistd.h> /* For NR_SYSCALLS */
23#include <asm/syscall.h> /* some archs define it here */
24#endif
25
26enum trace_type {
27 __TRACE_FIRST_TYPE = 0,
28
29 TRACE_FN,
30 TRACE_CTX,
31 TRACE_WAKE,
32 TRACE_STACK,
33 TRACE_PRINT,
34 TRACE_BPRINT,
35 TRACE_MMIO_RW,
36 TRACE_MMIO_MAP,
37 TRACE_BRANCH,
38 TRACE_GRAPH_RET,
39 TRACE_GRAPH_ENT,
40 TRACE_USER_STACK,
41 TRACE_BLK,
42 TRACE_BPUTS,
43 TRACE_HWLAT,
44 TRACE_RAW_DATA,
45
46 __TRACE_LAST_TYPE,
47};
48
49
50#undef __field
51#define __field(type, item) type item;
52
53#undef __field_struct
54#define __field_struct(type, item) __field(type, item)
55
56#undef __field_desc
57#define __field_desc(type, container, item)
58
59#undef __array
60#define __array(type, item, size) type item[size];
61
62#undef __array_desc
63#define __array_desc(type, container, item, size)
64
65#undef __dynamic_array
66#define __dynamic_array(type, item) type item[];
67
68#undef F_STRUCT
69#define F_STRUCT(args...) args
70
71#undef FTRACE_ENTRY
72#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
73 struct struct_name { \
74 struct trace_entry ent; \
75 tstruct \
76 }
77
78#undef FTRACE_ENTRY_DUP
79#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
80
81#undef FTRACE_ENTRY_REG
82#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
83 filter, regfn) \
84 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
85 filter)
86
87#undef FTRACE_ENTRY_PACKED
88#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \
89 filter) \
90 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
91 filter) __packed
92
93#include "trace_entries.h"
94
95/*
96 * syscalls are special, and need special handling, this is why
97 * they are not included in trace_entries.h
98 */
99struct syscall_trace_enter {
100 struct trace_entry ent;
101 int nr;
102 unsigned long args[];
103};
104
105struct syscall_trace_exit {
106 struct trace_entry ent;
107 int nr;
108 long ret;
109};
110
111struct kprobe_trace_entry_head {
112 struct trace_entry ent;
113 unsigned long ip;
114};
115
116struct kretprobe_trace_entry_head {
117 struct trace_entry ent;
118 unsigned long func;
119 unsigned long ret_ip;
120};
121
122/*
123 * trace_flag_type is an enumeration that holds different
124 * states when a trace occurs. These are:
125 * IRQS_OFF - interrupts were disabled
126 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
127 * NEED_RESCHED - reschedule is requested
128 * HARDIRQ - inside an interrupt handler
129 * SOFTIRQ - inside a softirq handler
130 */
131enum trace_flag_type {
132 TRACE_FLAG_IRQS_OFF = 0x01,
133 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
134 TRACE_FLAG_NEED_RESCHED = 0x04,
135 TRACE_FLAG_HARDIRQ = 0x08,
136 TRACE_FLAG_SOFTIRQ = 0x10,
137 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
138 TRACE_FLAG_NMI = 0x40,
139};
140
141#define TRACE_BUF_SIZE 1024
142
143struct trace_array;
144
145/*
146 * The CPU trace array - it consists of thousands of trace entries
147 * plus some other descriptor data: (for example which task started
148 * the trace, etc.)
149 */
150struct trace_array_cpu {
151 atomic_t disabled;
152 void *buffer_page; /* ring buffer spare */
153
154 unsigned long entries;
155 unsigned long saved_latency;
156 unsigned long critical_start;
157 unsigned long critical_end;
158 unsigned long critical_sequence;
159 unsigned long nice;
160 unsigned long policy;
161 unsigned long rt_priority;
162 unsigned long skipped_entries;
163 u64 preempt_timestamp;
164 pid_t pid;
165 kuid_t uid;
166 char comm[TASK_COMM_LEN];
167
168 bool ignore_pid;
169#ifdef CONFIG_FUNCTION_TRACER
170 bool ftrace_ignore_pid;
171#endif
172};
173
174struct tracer;
175struct trace_option_dentry;
176
177struct trace_buffer {
178 struct trace_array *tr;
179 struct ring_buffer *buffer;
180 struct trace_array_cpu __percpu *data;
181 u64 time_start;
182 int cpu;
183};
184
185#define TRACE_FLAGS_MAX_SIZE 32
186
187struct trace_options {
188 struct tracer *tracer;
189 struct trace_option_dentry *topts;
190};
191
192struct trace_pid_list {
193 int pid_max;
194 unsigned long *pids;
195};
196
197/*
198 * The trace array - an array of per-CPU trace arrays. This is the
199 * highest level data structure that individual tracers deal with.
200 * They have on/off state as well:
201 */
202struct trace_array {
203 struct list_head list;
204 char *name;
205 struct trace_buffer trace_buffer;
206#ifdef CONFIG_TRACER_MAX_TRACE
207 /*
208 * The max_buffer is used to snapshot the trace when a maximum
209 * latency is reached, or when the user initiates a snapshot.
210 * Some tracers will use this to store a maximum trace while
211 * it continues examining live traces.
212 *
213 * The buffers for the max_buffer are set up the same as the trace_buffer
214 * When a snapshot is taken, the buffer of the max_buffer is swapped
215 * with the buffer of the trace_buffer and the buffers are reset for
216 * the trace_buffer so the tracing can continue.
217 */
218 struct trace_buffer max_buffer;
219 bool allocated_snapshot;
220#endif
221#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
222 unsigned long max_latency;
223#endif
224 struct trace_pid_list __rcu *filtered_pids;
225 /*
226 * max_lock is used to protect the swapping of buffers
227 * when taking a max snapshot. The buffers themselves are
228 * protected by per_cpu spinlocks. But the action of the swap
229 * needs its own lock.
230 *
231 * This is defined as a arch_spinlock_t in order to help
232 * with performance when lockdep debugging is enabled.
233 *
234 * It is also used in other places outside the update_max_tr
235 * so it needs to be defined outside of the
236 * CONFIG_TRACER_MAX_TRACE.
237 */
238 arch_spinlock_t max_lock;
239 int buffer_disabled;
240#ifdef CONFIG_FTRACE_SYSCALLS
241 int sys_refcount_enter;
242 int sys_refcount_exit;
243 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
244 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
245#endif
246 int stop_count;
247 int clock_id;
248 int nr_topts;
249 bool clear_trace;
250 struct tracer *current_trace;
251 unsigned int trace_flags;
252 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
253 unsigned int flags;
254 raw_spinlock_t start_lock;
255 struct dentry *dir;
256 struct dentry *options;
257 struct dentry *percpu_dir;
258 struct dentry *event_dir;
259 struct trace_options *topts;
260 struct list_head systems;
261 struct list_head events;
262 struct trace_event_file *trace_marker_file;
263 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
264 int ref;
265#ifdef CONFIG_FUNCTION_TRACER
266 struct ftrace_ops *ops;
267 struct trace_pid_list __rcu *function_pids;
268#ifdef CONFIG_DYNAMIC_FTRACE
269 /* All of these are protected by the ftrace_lock */
270 struct list_head func_probes;
271 struct list_head mod_trace;
272 struct list_head mod_notrace;
273#endif
274 /* function tracing enabled */
275 int function_enabled;
276#endif
277 int time_stamp_abs_ref;
278 struct list_head hist_vars;
279};
280
281enum {
282 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
283};
284
285extern struct list_head ftrace_trace_arrays;
286
287extern struct mutex trace_types_lock;
288
289extern int trace_array_get(struct trace_array *tr);
290extern void trace_array_put(struct trace_array *tr);
291
292extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
293extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
294
295extern bool trace_clock_in_ns(struct trace_array *tr);
296
297/*
298 * The global tracer (top) should be the first trace array added,
299 * but we check the flag anyway.
300 */
301static inline struct trace_array *top_trace_array(void)
302{
303 struct trace_array *tr;
304
305 if (list_empty(&ftrace_trace_arrays))
306 return NULL;
307
308 tr = list_entry(ftrace_trace_arrays.prev,
309 typeof(*tr), list);
310 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
311 return tr;
312}
313
314#define FTRACE_CMP_TYPE(var, type) \
315 __builtin_types_compatible_p(typeof(var), type *)
316
317#undef IF_ASSIGN
318#define IF_ASSIGN(var, entry, etype, id) \
319 if (FTRACE_CMP_TYPE(var, etype)) { \
320 var = (typeof(var))(entry); \
321 WARN_ON(id && (entry)->type != id); \
322 break; \
323 }
324
325/* Will cause compile errors if type is not found. */
326extern void __ftrace_bad_type(void);
327
328/*
329 * The trace_assign_type is a verifier that the entry type is
330 * the same as the type being assigned. To add new types simply
331 * add a line with the following format:
332 *
333 * IF_ASSIGN(var, ent, type, id);
334 *
335 * Where "type" is the trace type that includes the trace_entry
336 * as the "ent" item. And "id" is the trace identifier that is
337 * used in the trace_type enum.
338 *
339 * If the type can have more than one id, then use zero.
340 */
341#define trace_assign_type(var, ent) \
342 do { \
343 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
344 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
345 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
346 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
347 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
348 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
349 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
350 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
351 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
352 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
353 TRACE_MMIO_RW); \
354 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
355 TRACE_MMIO_MAP); \
356 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
357 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
358 TRACE_GRAPH_ENT); \
359 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
360 TRACE_GRAPH_RET); \
361 __ftrace_bad_type(); \
362 } while (0)
363
364/*
365 * An option specific to a tracer. This is a boolean value.
366 * The bit is the bit index that sets its value on the
367 * flags value in struct tracer_flags.
368 */
369struct tracer_opt {
370 const char *name; /* Will appear on the trace_options file */
371 u32 bit; /* Mask assigned in val field in tracer_flags */
372};
373
374/*
375 * The set of specific options for a tracer. Your tracer
376 * have to set the initial value of the flags val.
377 */
378struct tracer_flags {
379 u32 val;
380 struct tracer_opt *opts;
381 struct tracer *trace;
382};
383
384/* Makes more easy to define a tracer opt */
385#define TRACER_OPT(s, b) .name = #s, .bit = b
386
387
388struct trace_option_dentry {
389 struct tracer_opt *opt;
390 struct tracer_flags *flags;
391 struct trace_array *tr;
392 struct dentry *entry;
393};
394
395/**
396 * struct tracer - a specific tracer and its callbacks to interact with tracefs
397 * @name: the name chosen to select it on the available_tracers file
398 * @init: called when one switches to this tracer (echo name > current_tracer)
399 * @reset: called when one switches to another tracer
400 * @start: called when tracing is unpaused (echo 1 > tracing_on)
401 * @stop: called when tracing is paused (echo 0 > tracing_on)
402 * @update_thresh: called when tracing_thresh is updated
403 * @open: called when the trace file is opened
404 * @pipe_open: called when the trace_pipe file is opened
405 * @close: called when the trace file is released
406 * @pipe_close: called when the trace_pipe file is released
407 * @read: override the default read callback on trace_pipe
408 * @splice_read: override the default splice_read callback on trace_pipe
409 * @selftest: selftest to run on boot (see trace_selftest.c)
410 * @print_headers: override the first lines that describe your columns
411 * @print_line: callback that prints a trace
412 * @set_flag: signals one of your private flags changed (trace_options file)
413 * @flags: your private flags
414 */
415struct tracer {
416 const char *name;
417 int (*init)(struct trace_array *tr);
418 void (*reset)(struct trace_array *tr);
419 void (*start)(struct trace_array *tr);
420 void (*stop)(struct trace_array *tr);
421 int (*update_thresh)(struct trace_array *tr);
422 void (*open)(struct trace_iterator *iter);
423 void (*pipe_open)(struct trace_iterator *iter);
424 void (*close)(struct trace_iterator *iter);
425 void (*pipe_close)(struct trace_iterator *iter);
426 ssize_t (*read)(struct trace_iterator *iter,
427 struct file *filp, char __user *ubuf,
428 size_t cnt, loff_t *ppos);
429 ssize_t (*splice_read)(struct trace_iterator *iter,
430 struct file *filp,
431 loff_t *ppos,
432 struct pipe_inode_info *pipe,
433 size_t len,
434 unsigned int flags);
435#ifdef CONFIG_FTRACE_STARTUP_TEST
436 int (*selftest)(struct tracer *trace,
437 struct trace_array *tr);
438#endif
439 void (*print_header)(struct seq_file *m);
440 enum print_line_t (*print_line)(struct trace_iterator *iter);
441 /* If you handled the flag setting, return 0 */
442 int (*set_flag)(struct trace_array *tr,
443 u32 old_flags, u32 bit, int set);
444 /* Return 0 if OK with change, else return non-zero */
445 int (*flag_changed)(struct trace_array *tr,
446 u32 mask, int set);
447 struct tracer *next;
448 struct tracer_flags *flags;
449 int enabled;
450 int ref;
451 bool print_max;
452 bool allow_instances;
453#ifdef CONFIG_TRACER_MAX_TRACE
454 bool use_max_tr;
455#endif
456 /* True if tracer cannot be enabled in kernel param */
457 bool noboot;
458};
459
460
461/* Only current can touch trace_recursion */
462
463/*
464 * For function tracing recursion:
465 * The order of these bits are important.
466 *
467 * When function tracing occurs, the following steps are made:
468 * If arch does not support a ftrace feature:
469 * call internal function (uses INTERNAL bits) which calls...
470 * If callback is registered to the "global" list, the list
471 * function is called and recursion checks the GLOBAL bits.
472 * then this function calls...
473 * The function callback, which can use the FTRACE bits to
474 * check for recursion.
475 *
476 * Now if the arch does not suppport a feature, and it calls
477 * the global list function which calls the ftrace callback
478 * all three of these steps will do a recursion protection.
479 * There's no reason to do one if the previous caller already
480 * did. The recursion that we are protecting against will
481 * go through the same steps again.
482 *
483 * To prevent the multiple recursion checks, if a recursion
484 * bit is set that is higher than the MAX bit of the current
485 * check, then we know that the check was made by the previous
486 * caller, and we can skip the current check.
487 */
488enum {
489 TRACE_BUFFER_BIT,
490 TRACE_BUFFER_NMI_BIT,
491 TRACE_BUFFER_IRQ_BIT,
492 TRACE_BUFFER_SIRQ_BIT,
493
494 /* Start of function recursion bits */
495 TRACE_FTRACE_BIT,
496 TRACE_FTRACE_NMI_BIT,
497 TRACE_FTRACE_IRQ_BIT,
498 TRACE_FTRACE_SIRQ_BIT,
499
500 /* INTERNAL_BITs must be greater than FTRACE_BITs */
501 TRACE_INTERNAL_BIT,
502 TRACE_INTERNAL_NMI_BIT,
503 TRACE_INTERNAL_IRQ_BIT,
504 TRACE_INTERNAL_SIRQ_BIT,
505
506 TRACE_BRANCH_BIT,
507/*
508 * Abuse of the trace_recursion.
509 * As we need a way to maintain state if we are tracing the function
510 * graph in irq because we want to trace a particular function that
511 * was called in irq context but we have irq tracing off. Since this
512 * can only be modified by current, we can reuse trace_recursion.
513 */
514 TRACE_IRQ_BIT,
515};
516
517#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
518#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
519#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
520
521#define TRACE_CONTEXT_BITS 4
522
523#define TRACE_FTRACE_START TRACE_FTRACE_BIT
524#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
525
526#define TRACE_LIST_START TRACE_INTERNAL_BIT
527#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
528
529#define TRACE_CONTEXT_MASK TRACE_LIST_MAX
530
531static __always_inline int trace_get_context_bit(void)
532{
533 int bit;
534
535 if (in_interrupt()) {
536 if (in_nmi())
537 bit = 0;
538
539 else if (in_irq())
540 bit = 1;
541 else
542 bit = 2;
543 } else
544 bit = 3;
545
546 return bit;
547}
548
549static __always_inline int trace_test_and_set_recursion(int start, int max)
550{
551 unsigned int val = current->trace_recursion;
552 int bit;
553
554 /* A previous recursion check was made */
555 if ((val & TRACE_CONTEXT_MASK) > max)
556 return 0;
557
558 bit = trace_get_context_bit() + start;
559 if (unlikely(val & (1 << bit)))
560 return -1;
561
562 val |= 1 << bit;
563 current->trace_recursion = val;
564 barrier();
565
566 return bit;
567}
568
569static __always_inline void trace_clear_recursion(int bit)
570{
571 unsigned int val = current->trace_recursion;
572
573 if (!bit)
574 return;
575
576 bit = 1 << bit;
577 val &= ~bit;
578
579 barrier();
580 current->trace_recursion = val;
581}
582
583static inline struct ring_buffer_iter *
584trace_buffer_iter(struct trace_iterator *iter, int cpu)
585{
586 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
587}
588
589int tracer_init(struct tracer *t, struct trace_array *tr);
590int tracing_is_enabled(void);
591void tracing_reset(struct trace_buffer *buf, int cpu);
592void tracing_reset_online_cpus(struct trace_buffer *buf);
593void tracing_reset_current(int cpu);
594void tracing_reset_all_online_cpus(void);
595int tracing_open_generic(struct inode *inode, struct file *filp);
596bool tracing_is_disabled(void);
597int tracer_tracing_is_on(struct trace_array *tr);
598void tracer_tracing_on(struct trace_array *tr);
599void tracer_tracing_off(struct trace_array *tr);
600struct dentry *trace_create_file(const char *name,
601 umode_t mode,
602 struct dentry *parent,
603 void *data,
604 const struct file_operations *fops);
605
606struct dentry *tracing_init_dentry(void);
607
608struct ring_buffer_event;
609
610struct ring_buffer_event *
611trace_buffer_lock_reserve(struct ring_buffer *buffer,
612 int type,
613 unsigned long len,
614 unsigned long flags,
615 int pc);
616
617struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
618 struct trace_array_cpu *data);
619
620struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
621 int *ent_cpu, u64 *ent_ts);
622
623void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
624 struct ring_buffer_event *event);
625
626int trace_empty(struct trace_iterator *iter);
627
628void *trace_find_next_entry_inc(struct trace_iterator *iter);
629
630void trace_init_global_iter(struct trace_iterator *iter);
631
632void tracing_iter_reset(struct trace_iterator *iter, int cpu);
633
634void trace_function(struct trace_array *tr,
635 unsigned long ip,
636 unsigned long parent_ip,
637 unsigned long flags, int pc);
638void trace_graph_function(struct trace_array *tr,
639 unsigned long ip,
640 unsigned long parent_ip,
641 unsigned long flags, int pc);
642void trace_latency_header(struct seq_file *m);
643void trace_default_header(struct seq_file *m);
644void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
645int trace_empty(struct trace_iterator *iter);
646
647void trace_graph_return(struct ftrace_graph_ret *trace);
648int trace_graph_entry(struct ftrace_graph_ent *trace);
649void set_graph_array(struct trace_array *tr);
650
651void tracing_start_cmdline_record(void);
652void tracing_stop_cmdline_record(void);
653void tracing_start_tgid_record(void);
654void tracing_stop_tgid_record(void);
655
656int register_tracer(struct tracer *type);
657int is_tracing_stopped(void);
658
659loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
660
661extern cpumask_var_t __read_mostly tracing_buffer_mask;
662
663#define for_each_tracing_cpu(cpu) \
664 for_each_cpu(cpu, tracing_buffer_mask)
665
666extern unsigned long nsecs_to_usecs(unsigned long nsecs);
667
668extern unsigned long tracing_thresh;
669
670/* PID filtering */
671
672extern int pid_max;
673
674bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
675 pid_t search_pid);
676bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
677 struct task_struct *task);
678void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
679 struct task_struct *self,
680 struct task_struct *task);
681void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
682void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
683int trace_pid_show(struct seq_file *m, void *v);
684void trace_free_pid_list(struct trace_pid_list *pid_list);
685int trace_pid_write(struct trace_pid_list *filtered_pids,
686 struct trace_pid_list **new_pid_list,
687 const char __user *ubuf, size_t cnt);
688
689#ifdef CONFIG_TRACER_MAX_TRACE
690void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
691void update_max_tr_single(struct trace_array *tr,
692 struct task_struct *tsk, int cpu);
693#endif /* CONFIG_TRACER_MAX_TRACE */
694
695#ifdef CONFIG_STACKTRACE
696void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
697 int pc);
698
699void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
700 int pc);
701#else
702static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
703 unsigned long flags, int pc)
704{
705}
706
707static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
708 int skip, int pc)
709{
710}
711#endif /* CONFIG_STACKTRACE */
712
713extern u64 ftrace_now(int cpu);
714
715extern void trace_find_cmdline(int pid, char comm[]);
716extern int trace_find_tgid(int pid);
717extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
718
719#ifdef CONFIG_DYNAMIC_FTRACE
720extern unsigned long ftrace_update_tot_cnt;
721void ftrace_init_trace_array(struct trace_array *tr);
722#else
723static inline void ftrace_init_trace_array(struct trace_array *tr) { }
724#endif
725#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
726extern int DYN_FTRACE_TEST_NAME(void);
727#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
728extern int DYN_FTRACE_TEST_NAME2(void);
729
730extern bool ring_buffer_expanded;
731extern bool tracing_selftest_disabled;
732
733#ifdef CONFIG_FTRACE_STARTUP_TEST
734extern int trace_selftest_startup_function(struct tracer *trace,
735 struct trace_array *tr);
736extern int trace_selftest_startup_function_graph(struct tracer *trace,
737 struct trace_array *tr);
738extern int trace_selftest_startup_irqsoff(struct tracer *trace,
739 struct trace_array *tr);
740extern int trace_selftest_startup_preemptoff(struct tracer *trace,
741 struct trace_array *tr);
742extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
743 struct trace_array *tr);
744extern int trace_selftest_startup_wakeup(struct tracer *trace,
745 struct trace_array *tr);
746extern int trace_selftest_startup_nop(struct tracer *trace,
747 struct trace_array *tr);
748extern int trace_selftest_startup_branch(struct tracer *trace,
749 struct trace_array *tr);
750/*
751 * Tracer data references selftest functions that only occur
752 * on boot up. These can be __init functions. Thus, when selftests
753 * are enabled, then the tracers need to reference __init functions.
754 */
755#define __tracer_data __refdata
756#else
757/* Tracers are seldom changed. Optimize when selftests are disabled. */
758#define __tracer_data __read_mostly
759#endif /* CONFIG_FTRACE_STARTUP_TEST */
760
761extern void *head_page(struct trace_array_cpu *data);
762extern unsigned long long ns2usecs(u64 nsec);
763extern int
764trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
765extern int
766trace_vprintk(unsigned long ip, const char *fmt, va_list args);
767extern int
768trace_array_vprintk(struct trace_array *tr,
769 unsigned long ip, const char *fmt, va_list args);
770int trace_array_printk(struct trace_array *tr,
771 unsigned long ip, const char *fmt, ...);
772int trace_array_printk_buf(struct ring_buffer *buffer,
773 unsigned long ip, const char *fmt, ...);
774void trace_printk_seq(struct trace_seq *s);
775enum print_line_t print_trace_line(struct trace_iterator *iter);
776
777extern char trace_find_mark(unsigned long long duration);
778
779struct ftrace_hash;
780
781struct ftrace_mod_load {
782 struct list_head list;
783 char *func;
784 char *module;
785 int enable;
786};
787
788enum {
789 FTRACE_HASH_FL_MOD = (1 << 0),
790};
791
792struct ftrace_hash {
793 unsigned long size_bits;
794 struct hlist_head *buckets;
795 unsigned long count;
796 unsigned long flags;
797 struct rcu_head rcu;
798};
799
800struct ftrace_func_entry *
801ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
802
803static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
804{
805 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
806}
807
808/* Standard output formatting function used for function return traces */
809#ifdef CONFIG_FUNCTION_GRAPH_TRACER
810
811/* Flag options */
812#define TRACE_GRAPH_PRINT_OVERRUN 0x1
813#define TRACE_GRAPH_PRINT_CPU 0x2
814#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
815#define TRACE_GRAPH_PRINT_PROC 0x8
816#define TRACE_GRAPH_PRINT_DURATION 0x10
817#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
818#define TRACE_GRAPH_PRINT_IRQS 0x40
819#define TRACE_GRAPH_PRINT_TAIL 0x80
820#define TRACE_GRAPH_SLEEP_TIME 0x100
821#define TRACE_GRAPH_GRAPH_TIME 0x200
822#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
823#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
824
825extern void ftrace_graph_sleep_time_control(bool enable);
826extern void ftrace_graph_graph_time_control(bool enable);
827
828extern enum print_line_t
829print_graph_function_flags(struct trace_iterator *iter, u32 flags);
830extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
831extern void
832trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
833extern void graph_trace_open(struct trace_iterator *iter);
834extern void graph_trace_close(struct trace_iterator *iter);
835extern int __trace_graph_entry(struct trace_array *tr,
836 struct ftrace_graph_ent *trace,
837 unsigned long flags, int pc);
838extern void __trace_graph_return(struct trace_array *tr,
839 struct ftrace_graph_ret *trace,
840 unsigned long flags, int pc);
841
842#ifdef CONFIG_DYNAMIC_FTRACE
843extern struct ftrace_hash *ftrace_graph_hash;
844extern struct ftrace_hash *ftrace_graph_notrace_hash;
845
846static inline int ftrace_graph_addr(unsigned long addr)
847{
848 int ret = 0;
849
850 preempt_disable_notrace();
851
852 if (ftrace_hash_empty(ftrace_graph_hash)) {
853 ret = 1;
854 goto out;
855 }
856
857 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
858 /*
859 * If no irqs are to be traced, but a set_graph_function
860 * is set, and called by an interrupt handler, we still
861 * want to trace it.
862 */
863 if (in_irq())
864 trace_recursion_set(TRACE_IRQ_BIT);
865 else
866 trace_recursion_clear(TRACE_IRQ_BIT);
867 ret = 1;
868 }
869
870out:
871 preempt_enable_notrace();
872 return ret;
873}
874
875static inline int ftrace_graph_notrace_addr(unsigned long addr)
876{
877 int ret = 0;
878
879 preempt_disable_notrace();
880
881 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
882 ret = 1;
883
884 preempt_enable_notrace();
885 return ret;
886}
887#else
888static inline int ftrace_graph_addr(unsigned long addr)
889{
890 return 1;
891}
892
893static inline int ftrace_graph_notrace_addr(unsigned long addr)
894{
895 return 0;
896}
897#endif /* CONFIG_DYNAMIC_FTRACE */
898
899extern unsigned int fgraph_max_depth;
900
901static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
902{
903 /* trace it when it is-nested-in or is a function enabled. */
904 return !(trace->depth || ftrace_graph_addr(trace->func)) ||
905 (trace->depth < 0) ||
906 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
907}
908
909#else /* CONFIG_FUNCTION_GRAPH_TRACER */
910static inline enum print_line_t
911print_graph_function_flags(struct trace_iterator *iter, u32 flags)
912{
913 return TRACE_TYPE_UNHANDLED;
914}
915#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
916
917extern struct list_head ftrace_pids;
918
919#ifdef CONFIG_FUNCTION_TRACER
920struct ftrace_func_command {
921 struct list_head list;
922 char *name;
923 int (*func)(struct trace_array *tr,
924 struct ftrace_hash *hash,
925 char *func, char *cmd,
926 char *params, int enable);
927};
928extern bool ftrace_filter_param __initdata;
929static inline int ftrace_trace_task(struct trace_array *tr)
930{
931 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
932}
933extern int ftrace_is_dead(void);
934int ftrace_create_function_files(struct trace_array *tr,
935 struct dentry *parent);
936void ftrace_destroy_function_files(struct trace_array *tr);
937void ftrace_init_global_array_ops(struct trace_array *tr);
938void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
939void ftrace_reset_array_ops(struct trace_array *tr);
940int using_ftrace_ops_list_func(void);
941void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
942void ftrace_init_tracefs_toplevel(struct trace_array *tr,
943 struct dentry *d_tracer);
944void ftrace_clear_pids(struct trace_array *tr);
945int init_function_trace(void);
946void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
947#else
948static inline int ftrace_trace_task(struct trace_array *tr)
949{
950 return 1;
951}
952static inline int ftrace_is_dead(void) { return 0; }
953static inline int
954ftrace_create_function_files(struct trace_array *tr,
955 struct dentry *parent)
956{
957 return 0;
958}
959static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
960static inline __init void
961ftrace_init_global_array_ops(struct trace_array *tr) { }
962static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
963static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
964static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
965static inline void ftrace_clear_pids(struct trace_array *tr) { }
966static inline int init_function_trace(void) { return 0; }
967static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
968/* ftace_func_t type is not defined, use macro instead of static inline */
969#define ftrace_init_array_ops(tr, func) do { } while (0)
970#endif /* CONFIG_FUNCTION_TRACER */
971
972#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
973
974struct ftrace_probe_ops {
975 void (*func)(unsigned long ip,
976 unsigned long parent_ip,
977 struct trace_array *tr,
978 struct ftrace_probe_ops *ops,
979 void *data);
980 int (*init)(struct ftrace_probe_ops *ops,
981 struct trace_array *tr,
982 unsigned long ip, void *init_data,
983 void **data);
984 void (*free)(struct ftrace_probe_ops *ops,
985 struct trace_array *tr,
986 unsigned long ip, void *data);
987 int (*print)(struct seq_file *m,
988 unsigned long ip,
989 struct ftrace_probe_ops *ops,
990 void *data);
991};
992
993struct ftrace_func_mapper;
994typedef int (*ftrace_mapper_func)(void *data);
995
996struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
997void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
998 unsigned long ip);
999int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1000 unsigned long ip, void *data);
1001void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1002 unsigned long ip);
1003void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1004 ftrace_mapper_func free_func);
1005
1006extern int
1007register_ftrace_function_probe(char *glob, struct trace_array *tr,
1008 struct ftrace_probe_ops *ops, void *data);
1009extern int
1010unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1011 struct ftrace_probe_ops *ops);
1012extern void clear_ftrace_function_probes(struct trace_array *tr);
1013
1014int register_ftrace_command(struct ftrace_func_command *cmd);
1015int unregister_ftrace_command(struct ftrace_func_command *cmd);
1016
1017void ftrace_create_filter_files(struct ftrace_ops *ops,
1018 struct dentry *parent);
1019void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1020#else
1021struct ftrace_func_command;
1022
1023static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1024{
1025 return -EINVAL;
1026}
1027static inline __init int unregister_ftrace_command(char *cmd_name)
1028{
1029 return -EINVAL;
1030}
1031static inline void clear_ftrace_function_probes(struct trace_array *tr)
1032{
1033}
1034
1035/*
1036 * The ops parameter passed in is usually undefined.
1037 * This must be a macro.
1038 */
1039#define ftrace_create_filter_files(ops, parent) do { } while (0)
1040#define ftrace_destroy_filter_files(ops) do { } while (0)
1041#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1042
1043bool ftrace_event_is_function(struct trace_event_call *call);
1044
1045/*
1046 * struct trace_parser - servers for reading the user input separated by spaces
1047 * @cont: set if the input is not complete - no final space char was found
1048 * @buffer: holds the parsed user input
1049 * @idx: user input length
1050 * @size: buffer size
1051 */
1052struct trace_parser {
1053 bool cont;
1054 char *buffer;
1055 unsigned idx;
1056 unsigned size;
1057};
1058
1059static inline bool trace_parser_loaded(struct trace_parser *parser)
1060{
1061 return (parser->idx != 0);
1062}
1063
1064static inline bool trace_parser_cont(struct trace_parser *parser)
1065{
1066 return parser->cont;
1067}
1068
1069static inline void trace_parser_clear(struct trace_parser *parser)
1070{
1071 parser->cont = false;
1072 parser->idx = 0;
1073}
1074
1075extern int trace_parser_get_init(struct trace_parser *parser, int size);
1076extern void trace_parser_put(struct trace_parser *parser);
1077extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1078 size_t cnt, loff_t *ppos);
1079
1080/*
1081 * Only create function graph options if function graph is configured.
1082 */
1083#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1084# define FGRAPH_FLAGS \
1085 C(DISPLAY_GRAPH, "display-graph"),
1086#else
1087# define FGRAPH_FLAGS
1088#endif
1089
1090#ifdef CONFIG_BRANCH_TRACER
1091# define BRANCH_FLAGS \
1092 C(BRANCH, "branch"),
1093#else
1094# define BRANCH_FLAGS
1095#endif
1096
1097#ifdef CONFIG_FUNCTION_TRACER
1098# define FUNCTION_FLAGS \
1099 C(FUNCTION, "function-trace"), \
1100 C(FUNC_FORK, "function-fork"),
1101# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1102#else
1103# define FUNCTION_FLAGS
1104# define FUNCTION_DEFAULT_FLAGS 0UL
1105# define TRACE_ITER_FUNC_FORK 0UL
1106#endif
1107
1108#ifdef CONFIG_STACKTRACE
1109# define STACK_FLAGS \
1110 C(STACKTRACE, "stacktrace"),
1111#else
1112# define STACK_FLAGS
1113#endif
1114
1115/*
1116 * trace_iterator_flags is an enumeration that defines bit
1117 * positions into trace_flags that controls the output.
1118 *
1119 * NOTE: These bits must match the trace_options array in
1120 * trace.c (this macro guarantees it).
1121 */
1122#define TRACE_FLAGS \
1123 C(PRINT_PARENT, "print-parent"), \
1124 C(SYM_OFFSET, "sym-offset"), \
1125 C(SYM_ADDR, "sym-addr"), \
1126 C(VERBOSE, "verbose"), \
1127 C(RAW, "raw"), \
1128 C(HEX, "hex"), \
1129 C(BIN, "bin"), \
1130 C(BLOCK, "block"), \
1131 C(PRINTK, "trace_printk"), \
1132 C(ANNOTATE, "annotate"), \
1133 C(USERSTACKTRACE, "userstacktrace"), \
1134 C(SYM_USEROBJ, "sym-userobj"), \
1135 C(PRINTK_MSGONLY, "printk-msg-only"), \
1136 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1137 C(LATENCY_FMT, "latency-format"), \
1138 C(RECORD_CMD, "record-cmd"), \
1139 C(RECORD_TGID, "record-tgid"), \
1140 C(OVERWRITE, "overwrite"), \
1141 C(STOP_ON_FREE, "disable_on_free"), \
1142 C(IRQ_INFO, "irq-info"), \
1143 C(MARKERS, "markers"), \
1144 C(EVENT_FORK, "event-fork"), \
1145 FUNCTION_FLAGS \
1146 FGRAPH_FLAGS \
1147 STACK_FLAGS \
1148 BRANCH_FLAGS
1149
1150/*
1151 * By defining C, we can make TRACE_FLAGS a list of bit names
1152 * that will define the bits for the flag masks.
1153 */
1154#undef C
1155#define C(a, b) TRACE_ITER_##a##_BIT
1156
1157enum trace_iterator_bits {
1158 TRACE_FLAGS
1159 /* Make sure we don't go more than we have bits for */
1160 TRACE_ITER_LAST_BIT
1161};
1162
1163/*
1164 * By redefining C, we can make TRACE_FLAGS a list of masks that
1165 * use the bits as defined above.
1166 */
1167#undef C
1168#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1169
1170enum trace_iterator_flags { TRACE_FLAGS };
1171
1172/*
1173 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1174 * control the output of kernel symbols.
1175 */
1176#define TRACE_ITER_SYM_MASK \
1177 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1178
1179extern struct tracer nop_trace;
1180
1181#ifdef CONFIG_BRANCH_TRACER
1182extern int enable_branch_tracing(struct trace_array *tr);
1183extern void disable_branch_tracing(void);
1184static inline int trace_branch_enable(struct trace_array *tr)
1185{
1186 if (tr->trace_flags & TRACE_ITER_BRANCH)
1187 return enable_branch_tracing(tr);
1188 return 0;
1189}
1190static inline void trace_branch_disable(void)
1191{
1192 /* due to races, always disable */
1193 disable_branch_tracing();
1194}
1195#else
1196static inline int trace_branch_enable(struct trace_array *tr)
1197{
1198 return 0;
1199}
1200static inline void trace_branch_disable(void)
1201{
1202}
1203#endif /* CONFIG_BRANCH_TRACER */
1204
1205/* set ring buffers to default size if not already done so */
1206int tracing_update_buffers(void);
1207
1208struct ftrace_event_field {
1209 struct list_head link;
1210 const char *name;
1211 const char *type;
1212 int filter_type;
1213 int offset;
1214 int size;
1215 int is_signed;
1216};
1217
1218struct prog_entry;
1219
1220struct event_filter {
1221 struct prog_entry __rcu *prog;
1222 char *filter_string;
1223};
1224
1225struct event_subsystem {
1226 struct list_head list;
1227 const char *name;
1228 struct event_filter *filter;
1229 int ref_count;
1230};
1231
1232struct trace_subsystem_dir {
1233 struct list_head list;
1234 struct event_subsystem *subsystem;
1235 struct trace_array *tr;
1236 struct dentry *entry;
1237 int ref_count;
1238 int nr_events;
1239};
1240
1241extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1242 struct ring_buffer *buffer,
1243 struct ring_buffer_event *event);
1244
1245void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1246 struct ring_buffer *buffer,
1247 struct ring_buffer_event *event,
1248 unsigned long flags, int pc,
1249 struct pt_regs *regs);
1250
1251static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1252 struct ring_buffer *buffer,
1253 struct ring_buffer_event *event,
1254 unsigned long flags, int pc)
1255{
1256 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1257}
1258
1259DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1260DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1261void trace_buffered_event_disable(void);
1262void trace_buffered_event_enable(void);
1263
1264static inline void
1265__trace_event_discard_commit(struct ring_buffer *buffer,
1266 struct ring_buffer_event *event)
1267{
1268 if (this_cpu_read(trace_buffered_event) == event) {
1269 /* Simply release the temp buffer */
1270 this_cpu_dec(trace_buffered_event_cnt);
1271 return;
1272 }
1273 ring_buffer_discard_commit(buffer, event);
1274}
1275
1276/*
1277 * Helper function for event_trigger_unlock_commit{_regs}().
1278 * If there are event triggers attached to this event that requires
1279 * filtering against its fields, then they wil be called as the
1280 * entry already holds the field information of the current event.
1281 *
1282 * It also checks if the event should be discarded or not.
1283 * It is to be discarded if the event is soft disabled and the
1284 * event was only recorded to process triggers, or if the event
1285 * filter is active and this event did not match the filters.
1286 *
1287 * Returns true if the event is discarded, false otherwise.
1288 */
1289static inline bool
1290__event_trigger_test_discard(struct trace_event_file *file,
1291 struct ring_buffer *buffer,
1292 struct ring_buffer_event *event,
1293 void *entry,
1294 enum event_trigger_type *tt)
1295{
1296 unsigned long eflags = file->flags;
1297
1298 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1299 *tt = event_triggers_call(file, entry, event);
1300
1301 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1302 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1303 !filter_match_preds(file->filter, entry))) {
1304 __trace_event_discard_commit(buffer, event);
1305 return true;
1306 }
1307
1308 return false;
1309}
1310
1311/**
1312 * event_trigger_unlock_commit - handle triggers and finish event commit
1313 * @file: The file pointer assoctiated to the event
1314 * @buffer: The ring buffer that the event is being written to
1315 * @event: The event meta data in the ring buffer
1316 * @entry: The event itself
1317 * @irq_flags: The state of the interrupts at the start of the event
1318 * @pc: The state of the preempt count at the start of the event.
1319 *
1320 * This is a helper function to handle triggers that require data
1321 * from the event itself. It also tests the event against filters and
1322 * if the event is soft disabled and should be discarded.
1323 */
1324static inline void
1325event_trigger_unlock_commit(struct trace_event_file *file,
1326 struct ring_buffer *buffer,
1327 struct ring_buffer_event *event,
1328 void *entry, unsigned long irq_flags, int pc)
1329{
1330 enum event_trigger_type tt = ETT_NONE;
1331
1332 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1333 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1334
1335 if (tt)
1336 event_triggers_post_call(file, tt);
1337}
1338
1339/**
1340 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1341 * @file: The file pointer assoctiated to the event
1342 * @buffer: The ring buffer that the event is being written to
1343 * @event: The event meta data in the ring buffer
1344 * @entry: The event itself
1345 * @irq_flags: The state of the interrupts at the start of the event
1346 * @pc: The state of the preempt count at the start of the event.
1347 *
1348 * This is a helper function to handle triggers that require data
1349 * from the event itself. It also tests the event against filters and
1350 * if the event is soft disabled and should be discarded.
1351 *
1352 * Same as event_trigger_unlock_commit() but calls
1353 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1354 */
1355static inline void
1356event_trigger_unlock_commit_regs(struct trace_event_file *file,
1357 struct ring_buffer *buffer,
1358 struct ring_buffer_event *event,
1359 void *entry, unsigned long irq_flags, int pc,
1360 struct pt_regs *regs)
1361{
1362 enum event_trigger_type tt = ETT_NONE;
1363
1364 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1365 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1366 irq_flags, pc, regs);
1367
1368 if (tt)
1369 event_triggers_post_call(file, tt);
1370}
1371
1372#define FILTER_PRED_INVALID ((unsigned short)-1)
1373#define FILTER_PRED_IS_RIGHT (1 << 15)
1374#define FILTER_PRED_FOLD (1 << 15)
1375
1376/*
1377 * The max preds is the size of unsigned short with
1378 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1379 * and FOLD flags. The other is reserved.
1380 *
1381 * 2^14 preds is way more than enough.
1382 */
1383#define MAX_FILTER_PRED 16384
1384
1385struct filter_pred;
1386struct regex;
1387
1388typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1389
1390typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1391
1392enum regex_type {
1393 MATCH_FULL = 0,
1394 MATCH_FRONT_ONLY,
1395 MATCH_MIDDLE_ONLY,
1396 MATCH_END_ONLY,
1397 MATCH_GLOB,
1398};
1399
1400struct regex {
1401 char pattern[MAX_FILTER_STR_VAL];
1402 int len;
1403 int field_len;
1404 regex_match_func match;
1405};
1406
1407struct filter_pred {
1408 filter_pred_fn_t fn;
1409 u64 val;
1410 struct regex regex;
1411 unsigned short *ops;
1412 struct ftrace_event_field *field;
1413 int offset;
1414 int not;
1415 int op;
1416};
1417
1418static inline bool is_string_field(struct ftrace_event_field *field)
1419{
1420 return field->filter_type == FILTER_DYN_STRING ||
1421 field->filter_type == FILTER_STATIC_STRING ||
1422 field->filter_type == FILTER_PTR_STRING ||
1423 field->filter_type == FILTER_COMM;
1424}
1425
1426static inline bool is_function_field(struct ftrace_event_field *field)
1427{
1428 return field->filter_type == FILTER_TRACE_FN;
1429}
1430
1431extern enum regex_type
1432filter_parse_regex(char *buff, int len, char **search, int *not);
1433extern void print_event_filter(struct trace_event_file *file,
1434 struct trace_seq *s);
1435extern int apply_event_filter(struct trace_event_file *file,
1436 char *filter_string);
1437extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1438 char *filter_string);
1439extern void print_subsystem_event_filter(struct event_subsystem *system,
1440 struct trace_seq *s);
1441extern int filter_assign_type(const char *type);
1442extern int create_event_filter(struct trace_event_call *call,
1443 char *filter_str, bool set_str,
1444 struct event_filter **filterp);
1445extern void free_event_filter(struct event_filter *filter);
1446
1447struct ftrace_event_field *
1448trace_find_event_field(struct trace_event_call *call, char *name);
1449
1450extern void trace_event_enable_cmd_record(bool enable);
1451extern void trace_event_enable_tgid_record(bool enable);
1452
1453extern int event_trace_init(void);
1454extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1455extern int event_trace_del_tracer(struct trace_array *tr);
1456
1457extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1458 const char *system,
1459 const char *event);
1460extern struct trace_event_file *find_event_file(struct trace_array *tr,
1461 const char *system,
1462 const char *event);
1463
1464static inline void *event_file_data(struct file *filp)
1465{
1466 return READ_ONCE(file_inode(filp)->i_private);
1467}
1468
1469extern struct mutex event_mutex;
1470extern struct list_head ftrace_events;
1471
1472extern const struct file_operations event_trigger_fops;
1473extern const struct file_operations event_hist_fops;
1474
1475#ifdef CONFIG_HIST_TRIGGERS
1476extern int register_trigger_hist_cmd(void);
1477extern int register_trigger_hist_enable_disable_cmds(void);
1478#else
1479static inline int register_trigger_hist_cmd(void) { return 0; }
1480static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1481#endif
1482
1483extern int register_trigger_cmds(void);
1484extern void clear_event_triggers(struct trace_array *tr);
1485
1486struct event_trigger_data {
1487 unsigned long count;
1488 int ref;
1489 struct event_trigger_ops *ops;
1490 struct event_command *cmd_ops;
1491 struct event_filter __rcu *filter;
1492 char *filter_str;
1493 void *private_data;
1494 bool paused;
1495 bool paused_tmp;
1496 struct list_head list;
1497 char *name;
1498 struct list_head named_list;
1499 struct event_trigger_data *named_data;
1500};
1501
1502/* Avoid typos */
1503#define ENABLE_EVENT_STR "enable_event"
1504#define DISABLE_EVENT_STR "disable_event"
1505#define ENABLE_HIST_STR "enable_hist"
1506#define DISABLE_HIST_STR "disable_hist"
1507
1508struct enable_trigger_data {
1509 struct trace_event_file *file;
1510 bool enable;
1511 bool hist;
1512};
1513
1514extern int event_enable_trigger_print(struct seq_file *m,
1515 struct event_trigger_ops *ops,
1516 struct event_trigger_data *data);
1517extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1518 struct event_trigger_data *data);
1519extern int event_enable_trigger_func(struct event_command *cmd_ops,
1520 struct trace_event_file *file,
1521 char *glob, char *cmd, char *param);
1522extern int event_enable_register_trigger(char *glob,
1523 struct event_trigger_ops *ops,
1524 struct event_trigger_data *data,
1525 struct trace_event_file *file);
1526extern void event_enable_unregister_trigger(char *glob,
1527 struct event_trigger_ops *ops,
1528 struct event_trigger_data *test,
1529 struct trace_event_file *file);
1530extern void trigger_data_free(struct event_trigger_data *data);
1531extern int event_trigger_init(struct event_trigger_ops *ops,
1532 struct event_trigger_data *data);
1533extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1534 int trigger_enable);
1535extern void update_cond_flag(struct trace_event_file *file);
1536extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
1537 struct event_trigger_data *test,
1538 struct trace_event_file *file);
1539extern int set_trigger_filter(char *filter_str,
1540 struct event_trigger_data *trigger_data,
1541 struct trace_event_file *file);
1542extern struct event_trigger_data *find_named_trigger(const char *name);
1543extern bool is_named_trigger(struct event_trigger_data *test);
1544extern int save_named_trigger(const char *name,
1545 struct event_trigger_data *data);
1546extern void del_named_trigger(struct event_trigger_data *data);
1547extern void pause_named_trigger(struct event_trigger_data *data);
1548extern void unpause_named_trigger(struct event_trigger_data *data);
1549extern void set_named_trigger_data(struct event_trigger_data *data,
1550 struct event_trigger_data *named_data);
1551extern struct event_trigger_data *
1552get_named_trigger_data(struct event_trigger_data *data);
1553extern int register_event_command(struct event_command *cmd);
1554extern int unregister_event_command(struct event_command *cmd);
1555extern int register_trigger_hist_enable_disable_cmds(void);
1556
1557/**
1558 * struct event_trigger_ops - callbacks for trace event triggers
1559 *
1560 * The methods in this structure provide per-event trigger hooks for
1561 * various trigger operations.
1562 *
1563 * All the methods below, except for @init() and @free(), must be
1564 * implemented.
1565 *
1566 * @func: The trigger 'probe' function called when the triggering
1567 * event occurs. The data passed into this callback is the data
1568 * that was supplied to the event_command @reg() function that
1569 * registered the trigger (see struct event_command) along with
1570 * the trace record, rec.
1571 *
1572 * @init: An optional initialization function called for the trigger
1573 * when the trigger is registered (via the event_command reg()
1574 * function). This can be used to perform per-trigger
1575 * initialization such as incrementing a per-trigger reference
1576 * count, for instance. This is usually implemented by the
1577 * generic utility function @event_trigger_init() (see
1578 * trace_event_triggers.c).
1579 *
1580 * @free: An optional de-initialization function called for the
1581 * trigger when the trigger is unregistered (via the
1582 * event_command @reg() function). This can be used to perform
1583 * per-trigger de-initialization such as decrementing a
1584 * per-trigger reference count and freeing corresponding trigger
1585 * data, for instance. This is usually implemented by the
1586 * generic utility function @event_trigger_free() (see
1587 * trace_event_triggers.c).
1588 *
1589 * @print: The callback function invoked to have the trigger print
1590 * itself. This is usually implemented by a wrapper function
1591 * that calls the generic utility function @event_trigger_print()
1592 * (see trace_event_triggers.c).
1593 */
1594struct event_trigger_ops {
1595 void (*func)(struct event_trigger_data *data,
1596 void *rec,
1597 struct ring_buffer_event *rbe);
1598 int (*init)(struct event_trigger_ops *ops,
1599 struct event_trigger_data *data);
1600 void (*free)(struct event_trigger_ops *ops,
1601 struct event_trigger_data *data);
1602 int (*print)(struct seq_file *m,
1603 struct event_trigger_ops *ops,
1604 struct event_trigger_data *data);
1605};
1606
1607/**
1608 * struct event_command - callbacks and data members for event commands
1609 *
1610 * Event commands are invoked by users by writing the command name
1611 * into the 'trigger' file associated with a trace event. The
1612 * parameters associated with a specific invocation of an event
1613 * command are used to create an event trigger instance, which is
1614 * added to the list of trigger instances associated with that trace
1615 * event. When the event is hit, the set of triggers associated with
1616 * that event is invoked.
1617 *
1618 * The data members in this structure provide per-event command data
1619 * for various event commands.
1620 *
1621 * All the data members below, except for @post_trigger, must be set
1622 * for each event command.
1623 *
1624 * @name: The unique name that identifies the event command. This is
1625 * the name used when setting triggers via trigger files.
1626 *
1627 * @trigger_type: A unique id that identifies the event command
1628 * 'type'. This value has two purposes, the first to ensure that
1629 * only one trigger of the same type can be set at a given time
1630 * for a particular event e.g. it doesn't make sense to have both
1631 * a traceon and traceoff trigger attached to a single event at
1632 * the same time, so traceon and traceoff have the same type
1633 * though they have different names. The @trigger_type value is
1634 * also used as a bit value for deferring the actual trigger
1635 * action until after the current event is finished. Some
1636 * commands need to do this if they themselves log to the trace
1637 * buffer (see the @post_trigger() member below). @trigger_type
1638 * values are defined by adding new values to the trigger_type
1639 * enum in include/linux/trace_events.h.
1640 *
1641 * @flags: See the enum event_command_flags below.
1642 *
1643 * All the methods below, except for @set_filter() and @unreg_all(),
1644 * must be implemented.
1645 *
1646 * @func: The callback function responsible for parsing and
1647 * registering the trigger written to the 'trigger' file by the
1648 * user. It allocates the trigger instance and registers it with
1649 * the appropriate trace event. It makes use of the other
1650 * event_command callback functions to orchestrate this, and is
1651 * usually implemented by the generic utility function
1652 * @event_trigger_callback() (see trace_event_triggers.c).
1653 *
1654 * @reg: Adds the trigger to the list of triggers associated with the
1655 * event, and enables the event trigger itself, after
1656 * initializing it (via the event_trigger_ops @init() function).
1657 * This is also where commands can use the @trigger_type value to
1658 * make the decision as to whether or not multiple instances of
1659 * the trigger should be allowed. This is usually implemented by
1660 * the generic utility function @register_trigger() (see
1661 * trace_event_triggers.c).
1662 *
1663 * @unreg: Removes the trigger from the list of triggers associated
1664 * with the event, and disables the event trigger itself, after
1665 * initializing it (via the event_trigger_ops @free() function).
1666 * This is usually implemented by the generic utility function
1667 * @unregister_trigger() (see trace_event_triggers.c).
1668 *
1669 * @unreg_all: An optional function called to remove all the triggers
1670 * from the list of triggers associated with the event. Called
1671 * when a trigger file is opened in truncate mode.
1672 *
1673 * @set_filter: An optional function called to parse and set a filter
1674 * for the trigger. If no @set_filter() method is set for the
1675 * event command, filters set by the user for the command will be
1676 * ignored. This is usually implemented by the generic utility
1677 * function @set_trigger_filter() (see trace_event_triggers.c).
1678 *
1679 * @get_trigger_ops: The callback function invoked to retrieve the
1680 * event_trigger_ops implementation associated with the command.
1681 */
1682struct event_command {
1683 struct list_head list;
1684 char *name;
1685 enum event_trigger_type trigger_type;
1686 int flags;
1687 int (*func)(struct event_command *cmd_ops,
1688 struct trace_event_file *file,
1689 char *glob, char *cmd, char *params);
1690 int (*reg)(char *glob,
1691 struct event_trigger_ops *ops,
1692 struct event_trigger_data *data,
1693 struct trace_event_file *file);
1694 void (*unreg)(char *glob,
1695 struct event_trigger_ops *ops,
1696 struct event_trigger_data *data,
1697 struct trace_event_file *file);
1698 void (*unreg_all)(struct trace_event_file *file);
1699 int (*set_filter)(char *filter_str,
1700 struct event_trigger_data *data,
1701 struct trace_event_file *file);
1702 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1703};
1704
1705/**
1706 * enum event_command_flags - flags for struct event_command
1707 *
1708 * @POST_TRIGGER: A flag that says whether or not this command needs
1709 * to have its action delayed until after the current event has
1710 * been closed. Some triggers need to avoid being invoked while
1711 * an event is currently in the process of being logged, since
1712 * the trigger may itself log data into the trace buffer. Thus
1713 * we make sure the current event is committed before invoking
1714 * those triggers. To do that, the trigger invocation is split
1715 * in two - the first part checks the filter using the current
1716 * trace record; if a command has the @post_trigger flag set, it
1717 * sets a bit for itself in the return value, otherwise it
1718 * directly invokes the trigger. Once all commands have been
1719 * either invoked or set their return flag, the current record is
1720 * either committed or discarded. At that point, if any commands
1721 * have deferred their triggers, those commands are finally
1722 * invoked following the close of the current event. In other
1723 * words, if the event_trigger_ops @func() probe implementation
1724 * itself logs to the trace buffer, this flag should be set,
1725 * otherwise it can be left unspecified.
1726 *
1727 * @NEEDS_REC: A flag that says whether or not this command needs
1728 * access to the trace record in order to perform its function,
1729 * regardless of whether or not it has a filter associated with
1730 * it (filters make a trigger require access to the trace record
1731 * but are not always present).
1732 */
1733enum event_command_flags {
1734 EVENT_CMD_FL_POST_TRIGGER = 1,
1735 EVENT_CMD_FL_NEEDS_REC = 2,
1736};
1737
1738static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1739{
1740 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1741}
1742
1743static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1744{
1745 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1746}
1747
1748extern int trace_event_enable_disable(struct trace_event_file *file,
1749 int enable, int soft_disable);
1750extern int tracing_alloc_snapshot(void);
1751
1752extern const char *__start___trace_bprintk_fmt[];
1753extern const char *__stop___trace_bprintk_fmt[];
1754
1755extern const char *__start___tracepoint_str[];
1756extern const char *__stop___tracepoint_str[];
1757
1758void trace_printk_control(bool enabled);
1759void trace_printk_init_buffers(void);
1760void trace_printk_start_comm(void);
1761int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1762int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1763
1764#define MAX_EVENT_NAME_LEN 64
1765
1766extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1767extern ssize_t trace_parse_run_command(struct file *file,
1768 const char __user *buffer, size_t count, loff_t *ppos,
1769 int (*createfn)(int, char**));
1770
1771/*
1772 * Normal trace_printk() and friends allocates special buffers
1773 * to do the manipulation, as well as saves the print formats
1774 * into sections to display. But the trace infrastructure wants
1775 * to use these without the added overhead at the price of being
1776 * a bit slower (used mainly for warnings, where we don't care
1777 * about performance). The internal_trace_puts() is for such
1778 * a purpose.
1779 */
1780#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1781
1782#undef FTRACE_ENTRY
1783#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
1784 extern struct trace_event_call \
1785 __aligned(4) event_##call;
1786#undef FTRACE_ENTRY_DUP
1787#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1788 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1789 filter)
1790#undef FTRACE_ENTRY_PACKED
1791#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
1792 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1793 filter)
1794
1795#include "trace_entries.h"
1796
1797#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1798int perf_ftrace_event_register(struct trace_event_call *call,
1799 enum trace_reg type, void *data);
1800#else
1801#define perf_ftrace_event_register NULL
1802#endif
1803
1804#ifdef CONFIG_FTRACE_SYSCALLS
1805void init_ftrace_syscalls(void);
1806const char *get_syscall_name(int syscall);
1807#else
1808static inline void init_ftrace_syscalls(void) { }
1809static inline const char *get_syscall_name(int syscall)
1810{
1811 return NULL;
1812}
1813#endif
1814
1815#ifdef CONFIG_EVENT_TRACING
1816void trace_event_init(void);
1817void trace_event_eval_update(struct trace_eval_map **map, int len);
1818#else
1819static inline void __init trace_event_init(void) { }
1820static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1821#endif
1822
1823#ifdef CONFIG_TRACER_SNAPSHOT
1824void tracing_snapshot_instance(struct trace_array *tr);
1825int tracing_alloc_snapshot_instance(struct trace_array *tr);
1826#else
1827static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1828static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1829{
1830 return 0;
1831}
1832#endif
1833
1834extern struct trace_iterator *tracepoint_print_iter;
1835
1836#endif /* _LINUX_KERNEL_TRACE_H */