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1#ifndef _LINUX_KERNEL_TRACE_H
2#define _LINUX_KERNEL_TRACE_H
3
4#include <linux/fs.h>
5#include <linux/atomic.h>
6#include <linux/sched.h>
7#include <linux/clocksource.h>
8#include <linux/ring_buffer.h>
9#include <linux/mmiotrace.h>
10#include <linux/tracepoint.h>
11#include <linux/ftrace.h>
12#include <linux/hw_breakpoint.h>
13#include <linux/trace_seq.h>
14#include <linux/ftrace_event.h>
15
16enum trace_type {
17 __TRACE_FIRST_TYPE = 0,
18
19 TRACE_FN,
20 TRACE_CTX,
21 TRACE_WAKE,
22 TRACE_STACK,
23 TRACE_PRINT,
24 TRACE_BPRINT,
25 TRACE_MMIO_RW,
26 TRACE_MMIO_MAP,
27 TRACE_BRANCH,
28 TRACE_GRAPH_RET,
29 TRACE_GRAPH_ENT,
30 TRACE_USER_STACK,
31 TRACE_BLK,
32
33 __TRACE_LAST_TYPE,
34};
35
36
37#undef __field
38#define __field(type, item) type item;
39
40#undef __field_struct
41#define __field_struct(type, item) __field(type, item)
42
43#undef __field_desc
44#define __field_desc(type, container, item)
45
46#undef __array
47#define __array(type, item, size) type item[size];
48
49#undef __array_desc
50#define __array_desc(type, container, item, size)
51
52#undef __dynamic_array
53#define __dynamic_array(type, item) type item[];
54
55#undef F_STRUCT
56#define F_STRUCT(args...) args
57
58#undef FTRACE_ENTRY
59#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
60 struct struct_name { \
61 struct trace_entry ent; \
62 tstruct \
63 }
64
65#undef TP_ARGS
66#define TP_ARGS(args...) args
67
68#undef FTRACE_ENTRY_DUP
69#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
70
71#undef FTRACE_ENTRY_REG
72#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
73 filter, regfn) \
74 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
75 filter)
76
77#include "trace_entries.h"
78
79/*
80 * syscalls are special, and need special handling, this is why
81 * they are not included in trace_entries.h
82 */
83struct syscall_trace_enter {
84 struct trace_entry ent;
85 int nr;
86 unsigned long args[];
87};
88
89struct syscall_trace_exit {
90 struct trace_entry ent;
91 int nr;
92 long ret;
93};
94
95struct kprobe_trace_entry_head {
96 struct trace_entry ent;
97 unsigned long ip;
98};
99
100struct kretprobe_trace_entry_head {
101 struct trace_entry ent;
102 unsigned long func;
103 unsigned long ret_ip;
104};
105
106struct uprobe_trace_entry_head {
107 struct trace_entry ent;
108 unsigned long ip;
109};
110
111/*
112 * trace_flag_type is an enumeration that holds different
113 * states when a trace occurs. These are:
114 * IRQS_OFF - interrupts were disabled
115 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
116 * NEED_RESCHED - reschedule is requested
117 * HARDIRQ - inside an interrupt handler
118 * SOFTIRQ - inside a softirq handler
119 */
120enum trace_flag_type {
121 TRACE_FLAG_IRQS_OFF = 0x01,
122 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
123 TRACE_FLAG_NEED_RESCHED = 0x04,
124 TRACE_FLAG_HARDIRQ = 0x08,
125 TRACE_FLAG_SOFTIRQ = 0x10,
126};
127
128#define TRACE_BUF_SIZE 1024
129
130/*
131 * The CPU trace array - it consists of thousands of trace entries
132 * plus some other descriptor data: (for example which task started
133 * the trace, etc.)
134 */
135struct trace_array_cpu {
136 atomic_t disabled;
137 void *buffer_page; /* ring buffer spare */
138
139 unsigned long entries;
140 unsigned long saved_latency;
141 unsigned long critical_start;
142 unsigned long critical_end;
143 unsigned long critical_sequence;
144 unsigned long nice;
145 unsigned long policy;
146 unsigned long rt_priority;
147 unsigned long skipped_entries;
148 cycle_t preempt_timestamp;
149 pid_t pid;
150 uid_t uid;
151 char comm[TASK_COMM_LEN];
152};
153
154/*
155 * The trace array - an array of per-CPU trace arrays. This is the
156 * highest level data structure that individual tracers deal with.
157 * They have on/off state as well:
158 */
159struct trace_array {
160 struct ring_buffer *buffer;
161 int cpu;
162 int buffer_disabled;
163 cycle_t time_start;
164 struct task_struct *waiter;
165 struct trace_array_cpu *data[NR_CPUS];
166};
167
168#define FTRACE_CMP_TYPE(var, type) \
169 __builtin_types_compatible_p(typeof(var), type *)
170
171#undef IF_ASSIGN
172#define IF_ASSIGN(var, entry, etype, id) \
173 if (FTRACE_CMP_TYPE(var, etype)) { \
174 var = (typeof(var))(entry); \
175 WARN_ON(id && (entry)->type != id); \
176 break; \
177 }
178
179/* Will cause compile errors if type is not found. */
180extern void __ftrace_bad_type(void);
181
182/*
183 * The trace_assign_type is a verifier that the entry type is
184 * the same as the type being assigned. To add new types simply
185 * add a line with the following format:
186 *
187 * IF_ASSIGN(var, ent, type, id);
188 *
189 * Where "type" is the trace type that includes the trace_entry
190 * as the "ent" item. And "id" is the trace identifier that is
191 * used in the trace_type enum.
192 *
193 * If the type can have more than one id, then use zero.
194 */
195#define trace_assign_type(var, ent) \
196 do { \
197 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
198 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
199 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
200 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
201 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
202 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
203 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
204 TRACE_MMIO_RW); \
205 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
206 TRACE_MMIO_MAP); \
207 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
208 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
209 TRACE_GRAPH_ENT); \
210 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
211 TRACE_GRAPH_RET); \
212 __ftrace_bad_type(); \
213 } while (0)
214
215/*
216 * An option specific to a tracer. This is a boolean value.
217 * The bit is the bit index that sets its value on the
218 * flags value in struct tracer_flags.
219 */
220struct tracer_opt {
221 const char *name; /* Will appear on the trace_options file */
222 u32 bit; /* Mask assigned in val field in tracer_flags */
223};
224
225/*
226 * The set of specific options for a tracer. Your tracer
227 * have to set the initial value of the flags val.
228 */
229struct tracer_flags {
230 u32 val;
231 struct tracer_opt *opts;
232};
233
234/* Makes more easy to define a tracer opt */
235#define TRACER_OPT(s, b) .name = #s, .bit = b
236
237
238/**
239 * struct tracer - a specific tracer and its callbacks to interact with debugfs
240 * @name: the name chosen to select it on the available_tracers file
241 * @init: called when one switches to this tracer (echo name > current_tracer)
242 * @reset: called when one switches to another tracer
243 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
244 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
245 * @open: called when the trace file is opened
246 * @pipe_open: called when the trace_pipe file is opened
247 * @wait_pipe: override how the user waits for traces on trace_pipe
248 * @close: called when the trace file is released
249 * @pipe_close: called when the trace_pipe file is released
250 * @read: override the default read callback on trace_pipe
251 * @splice_read: override the default splice_read callback on trace_pipe
252 * @selftest: selftest to run on boot (see trace_selftest.c)
253 * @print_headers: override the first lines that describe your columns
254 * @print_line: callback that prints a trace
255 * @set_flag: signals one of your private flags changed (trace_options file)
256 * @flags: your private flags
257 */
258struct tracer {
259 const char *name;
260 int (*init)(struct trace_array *tr);
261 void (*reset)(struct trace_array *tr);
262 void (*start)(struct trace_array *tr);
263 void (*stop)(struct trace_array *tr);
264 void (*open)(struct trace_iterator *iter);
265 void (*pipe_open)(struct trace_iterator *iter);
266 void (*wait_pipe)(struct trace_iterator *iter);
267 void (*close)(struct trace_iterator *iter);
268 void (*pipe_close)(struct trace_iterator *iter);
269 ssize_t (*read)(struct trace_iterator *iter,
270 struct file *filp, char __user *ubuf,
271 size_t cnt, loff_t *ppos);
272 ssize_t (*splice_read)(struct trace_iterator *iter,
273 struct file *filp,
274 loff_t *ppos,
275 struct pipe_inode_info *pipe,
276 size_t len,
277 unsigned int flags);
278#ifdef CONFIG_FTRACE_STARTUP_TEST
279 int (*selftest)(struct tracer *trace,
280 struct trace_array *tr);
281#endif
282 void (*print_header)(struct seq_file *m);
283 enum print_line_t (*print_line)(struct trace_iterator *iter);
284 /* If you handled the flag setting, return 0 */
285 int (*set_flag)(u32 old_flags, u32 bit, int set);
286 struct tracer *next;
287 struct tracer_flags *flags;
288 int print_max;
289 int use_max_tr;
290};
291
292
293/* Only current can touch trace_recursion */
294#define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
295#define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
296
297/* Ring buffer has the 10 LSB bits to count */
298#define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
299
300/* for function tracing recursion */
301#define TRACE_INTERNAL_BIT (1<<11)
302#define TRACE_GLOBAL_BIT (1<<12)
303#define TRACE_CONTROL_BIT (1<<13)
304
305/*
306 * Abuse of the trace_recursion.
307 * As we need a way to maintain state if we are tracing the function
308 * graph in irq because we want to trace a particular function that
309 * was called in irq context but we have irq tracing off. Since this
310 * can only be modified by current, we can reuse trace_recursion.
311 */
312#define TRACE_IRQ_BIT (1<<13)
313
314#define trace_recursion_set(bit) do { (current)->trace_recursion |= (bit); } while (0)
315#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(bit); } while (0)
316#define trace_recursion_test(bit) ((current)->trace_recursion & (bit))
317
318#define TRACE_PIPE_ALL_CPU -1
319
320int tracer_init(struct tracer *t, struct trace_array *tr);
321int tracing_is_enabled(void);
322void trace_wake_up(void);
323void tracing_reset(struct trace_array *tr, int cpu);
324void tracing_reset_online_cpus(struct trace_array *tr);
325void tracing_reset_current(int cpu);
326void tracing_reset_current_online_cpus(void);
327int tracing_open_generic(struct inode *inode, struct file *filp);
328struct dentry *trace_create_file(const char *name,
329 umode_t mode,
330 struct dentry *parent,
331 void *data,
332 const struct file_operations *fops);
333
334struct dentry *tracing_init_dentry(void);
335
336struct ring_buffer_event;
337
338struct ring_buffer_event *
339trace_buffer_lock_reserve(struct ring_buffer *buffer,
340 int type,
341 unsigned long len,
342 unsigned long flags,
343 int pc);
344void trace_buffer_unlock_commit(struct ring_buffer *buffer,
345 struct ring_buffer_event *event,
346 unsigned long flags, int pc);
347
348struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
349 struct trace_array_cpu *data);
350
351struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
352 int *ent_cpu, u64 *ent_ts);
353
354int trace_empty(struct trace_iterator *iter);
355
356void *trace_find_next_entry_inc(struct trace_iterator *iter);
357
358void trace_init_global_iter(struct trace_iterator *iter);
359
360void tracing_iter_reset(struct trace_iterator *iter, int cpu);
361
362void default_wait_pipe(struct trace_iterator *iter);
363void poll_wait_pipe(struct trace_iterator *iter);
364
365void ftrace(struct trace_array *tr,
366 struct trace_array_cpu *data,
367 unsigned long ip,
368 unsigned long parent_ip,
369 unsigned long flags, int pc);
370void tracing_sched_switch_trace(struct trace_array *tr,
371 struct task_struct *prev,
372 struct task_struct *next,
373 unsigned long flags, int pc);
374
375void tracing_sched_wakeup_trace(struct trace_array *tr,
376 struct task_struct *wakee,
377 struct task_struct *cur,
378 unsigned long flags, int pc);
379void trace_function(struct trace_array *tr,
380 unsigned long ip,
381 unsigned long parent_ip,
382 unsigned long flags, int pc);
383void trace_graph_function(struct trace_array *tr,
384 unsigned long ip,
385 unsigned long parent_ip,
386 unsigned long flags, int pc);
387void trace_latency_header(struct seq_file *m);
388void trace_default_header(struct seq_file *m);
389void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
390int trace_empty(struct trace_iterator *iter);
391
392void trace_graph_return(struct ftrace_graph_ret *trace);
393int trace_graph_entry(struct ftrace_graph_ent *trace);
394void set_graph_array(struct trace_array *tr);
395
396void tracing_start_cmdline_record(void);
397void tracing_stop_cmdline_record(void);
398void tracing_sched_switch_assign_trace(struct trace_array *tr);
399void tracing_stop_sched_switch_record(void);
400void tracing_start_sched_switch_record(void);
401int register_tracer(struct tracer *type);
402void unregister_tracer(struct tracer *type);
403int is_tracing_stopped(void);
404enum trace_file_type {
405 TRACE_FILE_LAT_FMT = 1,
406 TRACE_FILE_ANNOTATE = 2,
407};
408
409extern cpumask_var_t __read_mostly tracing_buffer_mask;
410
411#define for_each_tracing_cpu(cpu) \
412 for_each_cpu(cpu, tracing_buffer_mask)
413
414extern unsigned long nsecs_to_usecs(unsigned long nsecs);
415
416extern unsigned long tracing_thresh;
417
418#ifdef CONFIG_TRACER_MAX_TRACE
419extern unsigned long tracing_max_latency;
420
421void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
422void update_max_tr_single(struct trace_array *tr,
423 struct task_struct *tsk, int cpu);
424#endif /* CONFIG_TRACER_MAX_TRACE */
425
426#ifdef CONFIG_STACKTRACE
427void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
428 int skip, int pc);
429
430void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
431 int skip, int pc, struct pt_regs *regs);
432
433void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
434 int pc);
435
436void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
437 int pc);
438#else
439static inline void ftrace_trace_stack(struct ring_buffer *buffer,
440 unsigned long flags, int skip, int pc)
441{
442}
443
444static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
445 unsigned long flags, int skip,
446 int pc, struct pt_regs *regs)
447{
448}
449
450static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
451 unsigned long flags, int pc)
452{
453}
454
455static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
456 int skip, int pc)
457{
458}
459#endif /* CONFIG_STACKTRACE */
460
461extern cycle_t ftrace_now(int cpu);
462
463extern void trace_find_cmdline(int pid, char comm[]);
464
465#ifdef CONFIG_DYNAMIC_FTRACE
466extern unsigned long ftrace_update_tot_cnt;
467#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
468extern int DYN_FTRACE_TEST_NAME(void);
469#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
470extern int DYN_FTRACE_TEST_NAME2(void);
471#endif
472
473extern int ring_buffer_expanded;
474extern bool tracing_selftest_disabled;
475DECLARE_PER_CPU(int, ftrace_cpu_disabled);
476
477#ifdef CONFIG_FTRACE_STARTUP_TEST
478extern int trace_selftest_startup_function(struct tracer *trace,
479 struct trace_array *tr);
480extern int trace_selftest_startup_function_graph(struct tracer *trace,
481 struct trace_array *tr);
482extern int trace_selftest_startup_irqsoff(struct tracer *trace,
483 struct trace_array *tr);
484extern int trace_selftest_startup_preemptoff(struct tracer *trace,
485 struct trace_array *tr);
486extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
487 struct trace_array *tr);
488extern int trace_selftest_startup_wakeup(struct tracer *trace,
489 struct trace_array *tr);
490extern int trace_selftest_startup_nop(struct tracer *trace,
491 struct trace_array *tr);
492extern int trace_selftest_startup_sched_switch(struct tracer *trace,
493 struct trace_array *tr);
494extern int trace_selftest_startup_branch(struct tracer *trace,
495 struct trace_array *tr);
496#endif /* CONFIG_FTRACE_STARTUP_TEST */
497
498extern void *head_page(struct trace_array_cpu *data);
499extern unsigned long long ns2usecs(cycle_t nsec);
500extern int
501trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
502extern int
503trace_vprintk(unsigned long ip, const char *fmt, va_list args);
504extern int
505trace_array_vprintk(struct trace_array *tr,
506 unsigned long ip, const char *fmt, va_list args);
507int trace_array_printk(struct trace_array *tr,
508 unsigned long ip, const char *fmt, ...);
509void trace_printk_seq(struct trace_seq *s);
510enum print_line_t print_trace_line(struct trace_iterator *iter);
511
512extern unsigned long trace_flags;
513
514extern int trace_clock_id;
515
516/* Standard output formatting function used for function return traces */
517#ifdef CONFIG_FUNCTION_GRAPH_TRACER
518
519/* Flag options */
520#define TRACE_GRAPH_PRINT_OVERRUN 0x1
521#define TRACE_GRAPH_PRINT_CPU 0x2
522#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
523#define TRACE_GRAPH_PRINT_PROC 0x8
524#define TRACE_GRAPH_PRINT_DURATION 0x10
525#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
526
527extern enum print_line_t
528print_graph_function_flags(struct trace_iterator *iter, u32 flags);
529extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
530extern enum print_line_t
531trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
532extern void graph_trace_open(struct trace_iterator *iter);
533extern void graph_trace_close(struct trace_iterator *iter);
534extern int __trace_graph_entry(struct trace_array *tr,
535 struct ftrace_graph_ent *trace,
536 unsigned long flags, int pc);
537extern void __trace_graph_return(struct trace_array *tr,
538 struct ftrace_graph_ret *trace,
539 unsigned long flags, int pc);
540
541
542#ifdef CONFIG_DYNAMIC_FTRACE
543/* TODO: make this variable */
544#define FTRACE_GRAPH_MAX_FUNCS 32
545extern int ftrace_graph_filter_enabled;
546extern int ftrace_graph_count;
547extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
548
549static inline int ftrace_graph_addr(unsigned long addr)
550{
551 int i;
552
553 if (!ftrace_graph_filter_enabled)
554 return 1;
555
556 for (i = 0; i < ftrace_graph_count; i++) {
557 if (addr == ftrace_graph_funcs[i]) {
558 /*
559 * If no irqs are to be traced, but a set_graph_function
560 * is set, and called by an interrupt handler, we still
561 * want to trace it.
562 */
563 if (in_irq())
564 trace_recursion_set(TRACE_IRQ_BIT);
565 else
566 trace_recursion_clear(TRACE_IRQ_BIT);
567 return 1;
568 }
569 }
570
571 return 0;
572}
573#else
574static inline int ftrace_graph_addr(unsigned long addr)
575{
576 return 1;
577}
578#endif /* CONFIG_DYNAMIC_FTRACE */
579#else /* CONFIG_FUNCTION_GRAPH_TRACER */
580static inline enum print_line_t
581print_graph_function_flags(struct trace_iterator *iter, u32 flags)
582{
583 return TRACE_TYPE_UNHANDLED;
584}
585#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
586
587extern struct list_head ftrace_pids;
588
589#ifdef CONFIG_FUNCTION_TRACER
590static inline int ftrace_trace_task(struct task_struct *task)
591{
592 if (list_empty(&ftrace_pids))
593 return 1;
594
595 return test_tsk_trace_trace(task);
596}
597extern int ftrace_is_dead(void);
598#else
599static inline int ftrace_trace_task(struct task_struct *task)
600{
601 return 1;
602}
603static inline int ftrace_is_dead(void) { return 0; }
604#endif
605
606int ftrace_event_is_function(struct ftrace_event_call *call);
607
608/*
609 * struct trace_parser - servers for reading the user input separated by spaces
610 * @cont: set if the input is not complete - no final space char was found
611 * @buffer: holds the parsed user input
612 * @idx: user input length
613 * @size: buffer size
614 */
615struct trace_parser {
616 bool cont;
617 char *buffer;
618 unsigned idx;
619 unsigned size;
620};
621
622static inline bool trace_parser_loaded(struct trace_parser *parser)
623{
624 return (parser->idx != 0);
625}
626
627static inline bool trace_parser_cont(struct trace_parser *parser)
628{
629 return parser->cont;
630}
631
632static inline void trace_parser_clear(struct trace_parser *parser)
633{
634 parser->cont = false;
635 parser->idx = 0;
636}
637
638extern int trace_parser_get_init(struct trace_parser *parser, int size);
639extern void trace_parser_put(struct trace_parser *parser);
640extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
641 size_t cnt, loff_t *ppos);
642
643/*
644 * trace_iterator_flags is an enumeration that defines bit
645 * positions into trace_flags that controls the output.
646 *
647 * NOTE: These bits must match the trace_options array in
648 * trace.c.
649 */
650enum trace_iterator_flags {
651 TRACE_ITER_PRINT_PARENT = 0x01,
652 TRACE_ITER_SYM_OFFSET = 0x02,
653 TRACE_ITER_SYM_ADDR = 0x04,
654 TRACE_ITER_VERBOSE = 0x08,
655 TRACE_ITER_RAW = 0x10,
656 TRACE_ITER_HEX = 0x20,
657 TRACE_ITER_BIN = 0x40,
658 TRACE_ITER_BLOCK = 0x80,
659 TRACE_ITER_STACKTRACE = 0x100,
660 TRACE_ITER_PRINTK = 0x200,
661 TRACE_ITER_PREEMPTONLY = 0x400,
662 TRACE_ITER_BRANCH = 0x800,
663 TRACE_ITER_ANNOTATE = 0x1000,
664 TRACE_ITER_USERSTACKTRACE = 0x2000,
665 TRACE_ITER_SYM_USEROBJ = 0x4000,
666 TRACE_ITER_PRINTK_MSGONLY = 0x8000,
667 TRACE_ITER_CONTEXT_INFO = 0x10000, /* Print pid/cpu/time */
668 TRACE_ITER_LATENCY_FMT = 0x20000,
669 TRACE_ITER_SLEEP_TIME = 0x40000,
670 TRACE_ITER_GRAPH_TIME = 0x80000,
671 TRACE_ITER_RECORD_CMD = 0x100000,
672 TRACE_ITER_OVERWRITE = 0x200000,
673 TRACE_ITER_STOP_ON_FREE = 0x400000,
674 TRACE_ITER_IRQ_INFO = 0x800000,
675};
676
677/*
678 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
679 * control the output of kernel symbols.
680 */
681#define TRACE_ITER_SYM_MASK \
682 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
683
684extern struct tracer nop_trace;
685
686#ifdef CONFIG_BRANCH_TRACER
687extern int enable_branch_tracing(struct trace_array *tr);
688extern void disable_branch_tracing(void);
689static inline int trace_branch_enable(struct trace_array *tr)
690{
691 if (trace_flags & TRACE_ITER_BRANCH)
692 return enable_branch_tracing(tr);
693 return 0;
694}
695static inline void trace_branch_disable(void)
696{
697 /* due to races, always disable */
698 disable_branch_tracing();
699}
700#else
701static inline int trace_branch_enable(struct trace_array *tr)
702{
703 return 0;
704}
705static inline void trace_branch_disable(void)
706{
707}
708#endif /* CONFIG_BRANCH_TRACER */
709
710/* set ring buffers to default size if not already done so */
711int tracing_update_buffers(void);
712
713/* trace event type bit fields, not numeric */
714enum {
715 TRACE_EVENT_TYPE_PRINTF = 1,
716 TRACE_EVENT_TYPE_RAW = 2,
717};
718
719struct ftrace_event_field {
720 struct list_head link;
721 char *name;
722 char *type;
723 int filter_type;
724 int offset;
725 int size;
726 int is_signed;
727};
728
729struct event_filter {
730 int n_preds; /* Number assigned */
731 int a_preds; /* allocated */
732 struct filter_pred *preds;
733 struct filter_pred *root;
734 char *filter_string;
735};
736
737struct event_subsystem {
738 struct list_head list;
739 const char *name;
740 struct dentry *entry;
741 struct event_filter *filter;
742 int nr_events;
743 int ref_count;
744};
745
746#define FILTER_PRED_INVALID ((unsigned short)-1)
747#define FILTER_PRED_IS_RIGHT (1 << 15)
748#define FILTER_PRED_FOLD (1 << 15)
749
750/*
751 * The max preds is the size of unsigned short with
752 * two flags at the MSBs. One bit is used for both the IS_RIGHT
753 * and FOLD flags. The other is reserved.
754 *
755 * 2^14 preds is way more than enough.
756 */
757#define MAX_FILTER_PRED 16384
758
759struct filter_pred;
760struct regex;
761
762typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
763
764typedef int (*regex_match_func)(char *str, struct regex *r, int len);
765
766enum regex_type {
767 MATCH_FULL = 0,
768 MATCH_FRONT_ONLY,
769 MATCH_MIDDLE_ONLY,
770 MATCH_END_ONLY,
771};
772
773struct regex {
774 char pattern[MAX_FILTER_STR_VAL];
775 int len;
776 int field_len;
777 regex_match_func match;
778};
779
780struct filter_pred {
781 filter_pred_fn_t fn;
782 u64 val;
783 struct regex regex;
784 unsigned short *ops;
785 struct ftrace_event_field *field;
786 int offset;
787 int not;
788 int op;
789 unsigned short index;
790 unsigned short parent;
791 unsigned short left;
792 unsigned short right;
793};
794
795extern struct list_head ftrace_common_fields;
796
797extern enum regex_type
798filter_parse_regex(char *buff, int len, char **search, int *not);
799extern void print_event_filter(struct ftrace_event_call *call,
800 struct trace_seq *s);
801extern int apply_event_filter(struct ftrace_event_call *call,
802 char *filter_string);
803extern int apply_subsystem_event_filter(struct event_subsystem *system,
804 char *filter_string);
805extern void print_subsystem_event_filter(struct event_subsystem *system,
806 struct trace_seq *s);
807extern int filter_assign_type(const char *type);
808
809struct list_head *
810trace_get_fields(struct ftrace_event_call *event_call);
811
812static inline int
813filter_check_discard(struct ftrace_event_call *call, void *rec,
814 struct ring_buffer *buffer,
815 struct ring_buffer_event *event)
816{
817 if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
818 !filter_match_preds(call->filter, rec)) {
819 ring_buffer_discard_commit(buffer, event);
820 return 1;
821 }
822
823 return 0;
824}
825
826extern void trace_event_enable_cmd_record(bool enable);
827
828extern struct mutex event_mutex;
829extern struct list_head ftrace_events;
830
831extern const char *__start___trace_bprintk_fmt[];
832extern const char *__stop___trace_bprintk_fmt[];
833
834void trace_printk_init_buffers(void);
835
836#undef FTRACE_ENTRY
837#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
838 extern struct ftrace_event_call \
839 __attribute__((__aligned__(4))) event_##call;
840#undef FTRACE_ENTRY_DUP
841#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
842 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
843 filter)
844#include "trace_entries.h"
845
846#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
847int perf_ftrace_event_register(struct ftrace_event_call *call,
848 enum trace_reg type, void *data);
849#else
850#define perf_ftrace_event_register NULL
851#endif
852
853#endif /* _LINUX_KERNEL_TRACE_H */
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
23#ifdef CONFIG_FTRACE_SYSCALLS
24#include <asm/unistd.h> /* For NR_SYSCALLS */
25#include <asm/syscall.h> /* some archs define it here */
26#endif
27
28enum trace_type {
29 __TRACE_FIRST_TYPE = 0,
30
31 TRACE_FN,
32 TRACE_CTX,
33 TRACE_WAKE,
34 TRACE_STACK,
35 TRACE_PRINT,
36 TRACE_BPRINT,
37 TRACE_MMIO_RW,
38 TRACE_MMIO_MAP,
39 TRACE_BRANCH,
40 TRACE_GRAPH_RET,
41 TRACE_GRAPH_ENT,
42 TRACE_USER_STACK,
43 TRACE_BLK,
44 TRACE_BPUTS,
45 TRACE_HWLAT,
46 TRACE_RAW_DATA,
47
48 __TRACE_LAST_TYPE,
49};
50
51
52#undef __field
53#define __field(type, item) type item;
54
55#undef __field_fn
56#define __field_fn(type, item) type item;
57
58#undef __field_struct
59#define __field_struct(type, item) __field(type, item)
60
61#undef __field_desc
62#define __field_desc(type, container, item)
63
64#undef __field_packed
65#define __field_packed(type, container, item)
66
67#undef __array
68#define __array(type, item, size) type item[size];
69
70#undef __array_desc
71#define __array_desc(type, container, item, size)
72
73#undef __dynamic_array
74#define __dynamic_array(type, item) type item[];
75
76#undef F_STRUCT
77#define F_STRUCT(args...) args
78
79#undef FTRACE_ENTRY
80#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
81 struct struct_name { \
82 struct trace_entry ent; \
83 tstruct \
84 }
85
86#undef FTRACE_ENTRY_DUP
87#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
88
89#undef FTRACE_ENTRY_REG
90#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \
91 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
92
93#undef FTRACE_ENTRY_PACKED
94#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \
95 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
96
97#include "trace_entries.h"
98
99/* Use this for memory failure errors */
100#define MEM_FAIL(condition, fmt, ...) ({ \
101 static bool __section(.data.once) __warned; \
102 int __ret_warn_once = !!(condition); \
103 \
104 if (unlikely(__ret_warn_once && !__warned)) { \
105 __warned = true; \
106 pr_err("ERROR: " fmt, ##__VA_ARGS__); \
107 } \
108 unlikely(__ret_warn_once); \
109})
110
111/*
112 * syscalls are special, and need special handling, this is why
113 * they are not included in trace_entries.h
114 */
115struct syscall_trace_enter {
116 struct trace_entry ent;
117 int nr;
118 unsigned long args[];
119};
120
121struct syscall_trace_exit {
122 struct trace_entry ent;
123 int nr;
124 long ret;
125};
126
127struct kprobe_trace_entry_head {
128 struct trace_entry ent;
129 unsigned long ip;
130};
131
132struct kretprobe_trace_entry_head {
133 struct trace_entry ent;
134 unsigned long func;
135 unsigned long ret_ip;
136};
137
138/*
139 * trace_flag_type is an enumeration that holds different
140 * states when a trace occurs. These are:
141 * IRQS_OFF - interrupts were disabled
142 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
143 * NEED_RESCHED - reschedule is requested
144 * HARDIRQ - inside an interrupt handler
145 * SOFTIRQ - inside a softirq handler
146 */
147enum trace_flag_type {
148 TRACE_FLAG_IRQS_OFF = 0x01,
149 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
150 TRACE_FLAG_NEED_RESCHED = 0x04,
151 TRACE_FLAG_HARDIRQ = 0x08,
152 TRACE_FLAG_SOFTIRQ = 0x10,
153 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
154 TRACE_FLAG_NMI = 0x40,
155};
156
157#define TRACE_BUF_SIZE 1024
158
159struct trace_array;
160
161/*
162 * The CPU trace array - it consists of thousands of trace entries
163 * plus some other descriptor data: (for example which task started
164 * the trace, etc.)
165 */
166struct trace_array_cpu {
167 atomic_t disabled;
168 void *buffer_page; /* ring buffer spare */
169
170 unsigned long entries;
171 unsigned long saved_latency;
172 unsigned long critical_start;
173 unsigned long critical_end;
174 unsigned long critical_sequence;
175 unsigned long nice;
176 unsigned long policy;
177 unsigned long rt_priority;
178 unsigned long skipped_entries;
179 u64 preempt_timestamp;
180 pid_t pid;
181 kuid_t uid;
182 char comm[TASK_COMM_LEN];
183
184#ifdef CONFIG_FUNCTION_TRACER
185 int ftrace_ignore_pid;
186#endif
187 bool ignore_pid;
188};
189
190struct tracer;
191struct trace_option_dentry;
192
193struct array_buffer {
194 struct trace_array *tr;
195 struct trace_buffer *buffer;
196 struct trace_array_cpu __percpu *data;
197 u64 time_start;
198 int cpu;
199};
200
201#define TRACE_FLAGS_MAX_SIZE 32
202
203struct trace_options {
204 struct tracer *tracer;
205 struct trace_option_dentry *topts;
206};
207
208struct trace_pid_list {
209 int pid_max;
210 unsigned long *pids;
211};
212
213enum {
214 TRACE_PIDS = BIT(0),
215 TRACE_NO_PIDS = BIT(1),
216};
217
218static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
219 struct trace_pid_list *no_pid_list)
220{
221 /* Return true if the pid list in type has pids */
222 return ((type & TRACE_PIDS) && pid_list) ||
223 ((type & TRACE_NO_PIDS) && no_pid_list);
224}
225
226static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
227 struct trace_pid_list *no_pid_list)
228{
229 /*
230 * Turning off what is in @type, return true if the "other"
231 * pid list, still has pids in it.
232 */
233 return (!(type & TRACE_PIDS) && pid_list) ||
234 (!(type & TRACE_NO_PIDS) && no_pid_list);
235}
236
237typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
238
239/**
240 * struct cond_snapshot - conditional snapshot data and callback
241 *
242 * The cond_snapshot structure encapsulates a callback function and
243 * data associated with the snapshot for a given tracing instance.
244 *
245 * When a snapshot is taken conditionally, by invoking
246 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
247 * passed in turn to the cond_snapshot.update() function. That data
248 * can be compared by the update() implementation with the cond_data
249 * contained wihin the struct cond_snapshot instance associated with
250 * the trace_array. Because the tr->max_lock is held throughout the
251 * update() call, the update() function can directly retrieve the
252 * cond_snapshot and cond_data associated with the per-instance
253 * snapshot associated with the trace_array.
254 *
255 * The cond_snapshot.update() implementation can save data to be
256 * associated with the snapshot if it decides to, and returns 'true'
257 * in that case, or it returns 'false' if the conditional snapshot
258 * shouldn't be taken.
259 *
260 * The cond_snapshot instance is created and associated with the
261 * user-defined cond_data by tracing_cond_snapshot_enable().
262 * Likewise, the cond_snapshot instance is destroyed and is no longer
263 * associated with the trace instance by
264 * tracing_cond_snapshot_disable().
265 *
266 * The method below is required.
267 *
268 * @update: When a conditional snapshot is invoked, the update()
269 * callback function is invoked with the tr->max_lock held. The
270 * update() implementation signals whether or not to actually
271 * take the snapshot, by returning 'true' if so, 'false' if no
272 * snapshot should be taken. Because the max_lock is held for
273 * the duration of update(), the implementation is safe to
274 * directly retrieven and save any implementation data it needs
275 * to in association with the snapshot.
276 */
277struct cond_snapshot {
278 void *cond_data;
279 cond_update_fn_t update;
280};
281
282/*
283 * The trace array - an array of per-CPU trace arrays. This is the
284 * highest level data structure that individual tracers deal with.
285 * They have on/off state as well:
286 */
287struct trace_array {
288 struct list_head list;
289 char *name;
290 struct array_buffer array_buffer;
291#ifdef CONFIG_TRACER_MAX_TRACE
292 /*
293 * The max_buffer is used to snapshot the trace when a maximum
294 * latency is reached, or when the user initiates a snapshot.
295 * Some tracers will use this to store a maximum trace while
296 * it continues examining live traces.
297 *
298 * The buffers for the max_buffer are set up the same as the array_buffer
299 * When a snapshot is taken, the buffer of the max_buffer is swapped
300 * with the buffer of the array_buffer and the buffers are reset for
301 * the array_buffer so the tracing can continue.
302 */
303 struct array_buffer max_buffer;
304 bool allocated_snapshot;
305#endif
306#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
307 unsigned long max_latency;
308#ifdef CONFIG_FSNOTIFY
309 struct dentry *d_max_latency;
310 struct work_struct fsnotify_work;
311 struct irq_work fsnotify_irqwork;
312#endif
313#endif
314 struct trace_pid_list __rcu *filtered_pids;
315 struct trace_pid_list __rcu *filtered_no_pids;
316 /*
317 * max_lock is used to protect the swapping of buffers
318 * when taking a max snapshot. The buffers themselves are
319 * protected by per_cpu spinlocks. But the action of the swap
320 * needs its own lock.
321 *
322 * This is defined as a arch_spinlock_t in order to help
323 * with performance when lockdep debugging is enabled.
324 *
325 * It is also used in other places outside the update_max_tr
326 * so it needs to be defined outside of the
327 * CONFIG_TRACER_MAX_TRACE.
328 */
329 arch_spinlock_t max_lock;
330 int buffer_disabled;
331#ifdef CONFIG_FTRACE_SYSCALLS
332 int sys_refcount_enter;
333 int sys_refcount_exit;
334 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
335 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
336#endif
337 int stop_count;
338 int clock_id;
339 int nr_topts;
340 bool clear_trace;
341 int buffer_percent;
342 unsigned int n_err_log_entries;
343 struct tracer *current_trace;
344 unsigned int trace_flags;
345 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
346 unsigned int flags;
347 raw_spinlock_t start_lock;
348 struct list_head err_log;
349 struct dentry *dir;
350 struct dentry *options;
351 struct dentry *percpu_dir;
352 struct dentry *event_dir;
353 struct trace_options *topts;
354 struct list_head systems;
355 struct list_head events;
356 struct trace_event_file *trace_marker_file;
357 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
358 int ref;
359 int trace_ref;
360#ifdef CONFIG_FUNCTION_TRACER
361 struct ftrace_ops *ops;
362 struct trace_pid_list __rcu *function_pids;
363 struct trace_pid_list __rcu *function_no_pids;
364#ifdef CONFIG_DYNAMIC_FTRACE
365 /* All of these are protected by the ftrace_lock */
366 struct list_head func_probes;
367 struct list_head mod_trace;
368 struct list_head mod_notrace;
369#endif
370 /* function tracing enabled */
371 int function_enabled;
372#endif
373 int time_stamp_abs_ref;
374 struct list_head hist_vars;
375#ifdef CONFIG_TRACER_SNAPSHOT
376 struct cond_snapshot *cond_snapshot;
377#endif
378};
379
380enum {
381 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
382};
383
384extern struct list_head ftrace_trace_arrays;
385
386extern struct mutex trace_types_lock;
387
388extern int trace_array_get(struct trace_array *tr);
389extern int tracing_check_open_get_tr(struct trace_array *tr);
390extern struct trace_array *trace_array_find(const char *instance);
391extern struct trace_array *trace_array_find_get(const char *instance);
392
393extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
394extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
395
396extern bool trace_clock_in_ns(struct trace_array *tr);
397
398/*
399 * The global tracer (top) should be the first trace array added,
400 * but we check the flag anyway.
401 */
402static inline struct trace_array *top_trace_array(void)
403{
404 struct trace_array *tr;
405
406 if (list_empty(&ftrace_trace_arrays))
407 return NULL;
408
409 tr = list_entry(ftrace_trace_arrays.prev,
410 typeof(*tr), list);
411 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
412 return tr;
413}
414
415#define FTRACE_CMP_TYPE(var, type) \
416 __builtin_types_compatible_p(typeof(var), type *)
417
418#undef IF_ASSIGN
419#define IF_ASSIGN(var, entry, etype, id) \
420 if (FTRACE_CMP_TYPE(var, etype)) { \
421 var = (typeof(var))(entry); \
422 WARN_ON(id != 0 && (entry)->type != id); \
423 break; \
424 }
425
426/* Will cause compile errors if type is not found. */
427extern void __ftrace_bad_type(void);
428
429/*
430 * The trace_assign_type is a verifier that the entry type is
431 * the same as the type being assigned. To add new types simply
432 * add a line with the following format:
433 *
434 * IF_ASSIGN(var, ent, type, id);
435 *
436 * Where "type" is the trace type that includes the trace_entry
437 * as the "ent" item. And "id" is the trace identifier that is
438 * used in the trace_type enum.
439 *
440 * If the type can have more than one id, then use zero.
441 */
442#define trace_assign_type(var, ent) \
443 do { \
444 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
445 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
446 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
447 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
448 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
449 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
450 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
451 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
452 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
453 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
454 TRACE_MMIO_RW); \
455 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
456 TRACE_MMIO_MAP); \
457 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
458 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
459 TRACE_GRAPH_ENT); \
460 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
461 TRACE_GRAPH_RET); \
462 __ftrace_bad_type(); \
463 } while (0)
464
465/*
466 * An option specific to a tracer. This is a boolean value.
467 * The bit is the bit index that sets its value on the
468 * flags value in struct tracer_flags.
469 */
470struct tracer_opt {
471 const char *name; /* Will appear on the trace_options file */
472 u32 bit; /* Mask assigned in val field in tracer_flags */
473};
474
475/*
476 * The set of specific options for a tracer. Your tracer
477 * have to set the initial value of the flags val.
478 */
479struct tracer_flags {
480 u32 val;
481 struct tracer_opt *opts;
482 struct tracer *trace;
483};
484
485/* Makes more easy to define a tracer opt */
486#define TRACER_OPT(s, b) .name = #s, .bit = b
487
488
489struct trace_option_dentry {
490 struct tracer_opt *opt;
491 struct tracer_flags *flags;
492 struct trace_array *tr;
493 struct dentry *entry;
494};
495
496/**
497 * struct tracer - a specific tracer and its callbacks to interact with tracefs
498 * @name: the name chosen to select it on the available_tracers file
499 * @init: called when one switches to this tracer (echo name > current_tracer)
500 * @reset: called when one switches to another tracer
501 * @start: called when tracing is unpaused (echo 1 > tracing_on)
502 * @stop: called when tracing is paused (echo 0 > tracing_on)
503 * @update_thresh: called when tracing_thresh is updated
504 * @open: called when the trace file is opened
505 * @pipe_open: called when the trace_pipe file is opened
506 * @close: called when the trace file is released
507 * @pipe_close: called when the trace_pipe file is released
508 * @read: override the default read callback on trace_pipe
509 * @splice_read: override the default splice_read callback on trace_pipe
510 * @selftest: selftest to run on boot (see trace_selftest.c)
511 * @print_headers: override the first lines that describe your columns
512 * @print_line: callback that prints a trace
513 * @set_flag: signals one of your private flags changed (trace_options file)
514 * @flags: your private flags
515 */
516struct tracer {
517 const char *name;
518 int (*init)(struct trace_array *tr);
519 void (*reset)(struct trace_array *tr);
520 void (*start)(struct trace_array *tr);
521 void (*stop)(struct trace_array *tr);
522 int (*update_thresh)(struct trace_array *tr);
523 void (*open)(struct trace_iterator *iter);
524 void (*pipe_open)(struct trace_iterator *iter);
525 void (*close)(struct trace_iterator *iter);
526 void (*pipe_close)(struct trace_iterator *iter);
527 ssize_t (*read)(struct trace_iterator *iter,
528 struct file *filp, char __user *ubuf,
529 size_t cnt, loff_t *ppos);
530 ssize_t (*splice_read)(struct trace_iterator *iter,
531 struct file *filp,
532 loff_t *ppos,
533 struct pipe_inode_info *pipe,
534 size_t len,
535 unsigned int flags);
536#ifdef CONFIG_FTRACE_STARTUP_TEST
537 int (*selftest)(struct tracer *trace,
538 struct trace_array *tr);
539#endif
540 void (*print_header)(struct seq_file *m);
541 enum print_line_t (*print_line)(struct trace_iterator *iter);
542 /* If you handled the flag setting, return 0 */
543 int (*set_flag)(struct trace_array *tr,
544 u32 old_flags, u32 bit, int set);
545 /* Return 0 if OK with change, else return non-zero */
546 int (*flag_changed)(struct trace_array *tr,
547 u32 mask, int set);
548 struct tracer *next;
549 struct tracer_flags *flags;
550 int enabled;
551 bool print_max;
552 bool allow_instances;
553#ifdef CONFIG_TRACER_MAX_TRACE
554 bool use_max_tr;
555#endif
556 /* True if tracer cannot be enabled in kernel param */
557 bool noboot;
558};
559
560
561/* Only current can touch trace_recursion */
562
563/*
564 * For function tracing recursion:
565 * The order of these bits are important.
566 *
567 * When function tracing occurs, the following steps are made:
568 * If arch does not support a ftrace feature:
569 * call internal function (uses INTERNAL bits) which calls...
570 * If callback is registered to the "global" list, the list
571 * function is called and recursion checks the GLOBAL bits.
572 * then this function calls...
573 * The function callback, which can use the FTRACE bits to
574 * check for recursion.
575 *
576 * Now if the arch does not suppport a feature, and it calls
577 * the global list function which calls the ftrace callback
578 * all three of these steps will do a recursion protection.
579 * There's no reason to do one if the previous caller already
580 * did. The recursion that we are protecting against will
581 * go through the same steps again.
582 *
583 * To prevent the multiple recursion checks, if a recursion
584 * bit is set that is higher than the MAX bit of the current
585 * check, then we know that the check was made by the previous
586 * caller, and we can skip the current check.
587 */
588enum {
589 /* Function recursion bits */
590 TRACE_FTRACE_BIT,
591 TRACE_FTRACE_NMI_BIT,
592 TRACE_FTRACE_IRQ_BIT,
593 TRACE_FTRACE_SIRQ_BIT,
594
595 /* INTERNAL_BITs must be greater than FTRACE_BITs */
596 TRACE_INTERNAL_BIT,
597 TRACE_INTERNAL_NMI_BIT,
598 TRACE_INTERNAL_IRQ_BIT,
599 TRACE_INTERNAL_SIRQ_BIT,
600
601 TRACE_BRANCH_BIT,
602/*
603 * Abuse of the trace_recursion.
604 * As we need a way to maintain state if we are tracing the function
605 * graph in irq because we want to trace a particular function that
606 * was called in irq context but we have irq tracing off. Since this
607 * can only be modified by current, we can reuse trace_recursion.
608 */
609 TRACE_IRQ_BIT,
610
611 /* Set if the function is in the set_graph_function file */
612 TRACE_GRAPH_BIT,
613
614 /*
615 * In the very unlikely case that an interrupt came in
616 * at a start of graph tracing, and we want to trace
617 * the function in that interrupt, the depth can be greater
618 * than zero, because of the preempted start of a previous
619 * trace. In an even more unlikely case, depth could be 2
620 * if a softirq interrupted the start of graph tracing,
621 * followed by an interrupt preempting a start of graph
622 * tracing in the softirq, and depth can even be 3
623 * if an NMI came in at the start of an interrupt function
624 * that preempted a softirq start of a function that
625 * preempted normal context!!!! Luckily, it can't be
626 * greater than 3, so the next two bits are a mask
627 * of what the depth is when we set TRACE_GRAPH_BIT
628 */
629
630 TRACE_GRAPH_DEPTH_START_BIT,
631 TRACE_GRAPH_DEPTH_END_BIT,
632
633 /*
634 * To implement set_graph_notrace, if this bit is set, we ignore
635 * function graph tracing of called functions, until the return
636 * function is called to clear it.
637 */
638 TRACE_GRAPH_NOTRACE_BIT,
639};
640
641#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
642#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
643#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
644
645#define trace_recursion_depth() \
646 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
647#define trace_recursion_set_depth(depth) \
648 do { \
649 current->trace_recursion &= \
650 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \
651 current->trace_recursion |= \
652 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \
653 } while (0)
654
655#define TRACE_CONTEXT_BITS 4
656
657#define TRACE_FTRACE_START TRACE_FTRACE_BIT
658#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
659
660#define TRACE_LIST_START TRACE_INTERNAL_BIT
661#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
662
663#define TRACE_CONTEXT_MASK TRACE_LIST_MAX
664
665static __always_inline int trace_get_context_bit(void)
666{
667 int bit;
668
669 if (in_interrupt()) {
670 if (in_nmi())
671 bit = 0;
672
673 else if (in_irq())
674 bit = 1;
675 else
676 bit = 2;
677 } else
678 bit = 3;
679
680 return bit;
681}
682
683static __always_inline int trace_test_and_set_recursion(int start, int max)
684{
685 unsigned int val = current->trace_recursion;
686 int bit;
687
688 /* A previous recursion check was made */
689 if ((val & TRACE_CONTEXT_MASK) > max)
690 return 0;
691
692 bit = trace_get_context_bit() + start;
693 if (unlikely(val & (1 << bit)))
694 return -1;
695
696 val |= 1 << bit;
697 current->trace_recursion = val;
698 barrier();
699
700 return bit;
701}
702
703static __always_inline void trace_clear_recursion(int bit)
704{
705 unsigned int val = current->trace_recursion;
706
707 if (!bit)
708 return;
709
710 bit = 1 << bit;
711 val &= ~bit;
712
713 barrier();
714 current->trace_recursion = val;
715}
716
717static inline struct ring_buffer_iter *
718trace_buffer_iter(struct trace_iterator *iter, int cpu)
719{
720 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
721}
722
723int tracer_init(struct tracer *t, struct trace_array *tr);
724int tracing_is_enabled(void);
725void tracing_reset_online_cpus(struct array_buffer *buf);
726void tracing_reset_current(int cpu);
727void tracing_reset_all_online_cpus(void);
728int tracing_open_generic(struct inode *inode, struct file *filp);
729int tracing_open_generic_tr(struct inode *inode, struct file *filp);
730bool tracing_is_disabled(void);
731bool tracer_tracing_is_on(struct trace_array *tr);
732void tracer_tracing_on(struct trace_array *tr);
733void tracer_tracing_off(struct trace_array *tr);
734struct dentry *trace_create_file(const char *name,
735 umode_t mode,
736 struct dentry *parent,
737 void *data,
738 const struct file_operations *fops);
739
740struct dentry *tracing_init_dentry(void);
741
742struct ring_buffer_event;
743
744struct ring_buffer_event *
745trace_buffer_lock_reserve(struct trace_buffer *buffer,
746 int type,
747 unsigned long len,
748 unsigned long flags,
749 int pc);
750
751struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
752 struct trace_array_cpu *data);
753
754struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
755 int *ent_cpu, u64 *ent_ts);
756
757void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
758 struct ring_buffer_event *event);
759
760int trace_empty(struct trace_iterator *iter);
761
762void *trace_find_next_entry_inc(struct trace_iterator *iter);
763
764void trace_init_global_iter(struct trace_iterator *iter);
765
766void tracing_iter_reset(struct trace_iterator *iter, int cpu);
767
768unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
769unsigned long trace_total_entries(struct trace_array *tr);
770
771void trace_function(struct trace_array *tr,
772 unsigned long ip,
773 unsigned long parent_ip,
774 unsigned long flags, int pc);
775void trace_graph_function(struct trace_array *tr,
776 unsigned long ip,
777 unsigned long parent_ip,
778 unsigned long flags, int pc);
779void trace_latency_header(struct seq_file *m);
780void trace_default_header(struct seq_file *m);
781void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
782int trace_empty(struct trace_iterator *iter);
783
784void trace_graph_return(struct ftrace_graph_ret *trace);
785int trace_graph_entry(struct ftrace_graph_ent *trace);
786void set_graph_array(struct trace_array *tr);
787
788void tracing_start_cmdline_record(void);
789void tracing_stop_cmdline_record(void);
790void tracing_start_tgid_record(void);
791void tracing_stop_tgid_record(void);
792
793int register_tracer(struct tracer *type);
794int is_tracing_stopped(void);
795
796loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
797
798extern cpumask_var_t __read_mostly tracing_buffer_mask;
799
800#define for_each_tracing_cpu(cpu) \
801 for_each_cpu(cpu, tracing_buffer_mask)
802
803extern unsigned long nsecs_to_usecs(unsigned long nsecs);
804
805extern unsigned long tracing_thresh;
806
807/* PID filtering */
808
809extern int pid_max;
810
811bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
812 pid_t search_pid);
813bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
814 struct trace_pid_list *filtered_no_pids,
815 struct task_struct *task);
816void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
817 struct task_struct *self,
818 struct task_struct *task);
819void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
820void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
821int trace_pid_show(struct seq_file *m, void *v);
822void trace_free_pid_list(struct trace_pid_list *pid_list);
823int trace_pid_write(struct trace_pid_list *filtered_pids,
824 struct trace_pid_list **new_pid_list,
825 const char __user *ubuf, size_t cnt);
826
827#ifdef CONFIG_TRACER_MAX_TRACE
828void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
829 void *cond_data);
830void update_max_tr_single(struct trace_array *tr,
831 struct task_struct *tsk, int cpu);
832#endif /* CONFIG_TRACER_MAX_TRACE */
833
834#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
835 defined(CONFIG_FSNOTIFY)
836
837void latency_fsnotify(struct trace_array *tr);
838
839#else
840
841static inline void latency_fsnotify(struct trace_array *tr) { }
842
843#endif
844
845#ifdef CONFIG_STACKTRACE
846void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
847 int pc);
848#else
849static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
850 int skip, int pc)
851{
852}
853#endif /* CONFIG_STACKTRACE */
854
855extern u64 ftrace_now(int cpu);
856
857extern void trace_find_cmdline(int pid, char comm[]);
858extern int trace_find_tgid(int pid);
859extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
860
861#ifdef CONFIG_DYNAMIC_FTRACE
862extern unsigned long ftrace_update_tot_cnt;
863extern unsigned long ftrace_number_of_pages;
864extern unsigned long ftrace_number_of_groups;
865void ftrace_init_trace_array(struct trace_array *tr);
866#else
867static inline void ftrace_init_trace_array(struct trace_array *tr) { }
868#endif
869#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
870extern int DYN_FTRACE_TEST_NAME(void);
871#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
872extern int DYN_FTRACE_TEST_NAME2(void);
873
874extern bool ring_buffer_expanded;
875extern bool tracing_selftest_disabled;
876
877#ifdef CONFIG_FTRACE_STARTUP_TEST
878extern int trace_selftest_startup_function(struct tracer *trace,
879 struct trace_array *tr);
880extern int trace_selftest_startup_function_graph(struct tracer *trace,
881 struct trace_array *tr);
882extern int trace_selftest_startup_irqsoff(struct tracer *trace,
883 struct trace_array *tr);
884extern int trace_selftest_startup_preemptoff(struct tracer *trace,
885 struct trace_array *tr);
886extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
887 struct trace_array *tr);
888extern int trace_selftest_startup_wakeup(struct tracer *trace,
889 struct trace_array *tr);
890extern int trace_selftest_startup_nop(struct tracer *trace,
891 struct trace_array *tr);
892extern int trace_selftest_startup_branch(struct tracer *trace,
893 struct trace_array *tr);
894/*
895 * Tracer data references selftest functions that only occur
896 * on boot up. These can be __init functions. Thus, when selftests
897 * are enabled, then the tracers need to reference __init functions.
898 */
899#define __tracer_data __refdata
900#else
901/* Tracers are seldom changed. Optimize when selftests are disabled. */
902#define __tracer_data __read_mostly
903#endif /* CONFIG_FTRACE_STARTUP_TEST */
904
905extern void *head_page(struct trace_array_cpu *data);
906extern unsigned long long ns2usecs(u64 nsec);
907extern int
908trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
909extern int
910trace_vprintk(unsigned long ip, const char *fmt, va_list args);
911extern int
912trace_array_vprintk(struct trace_array *tr,
913 unsigned long ip, const char *fmt, va_list args);
914int trace_array_printk_buf(struct trace_buffer *buffer,
915 unsigned long ip, const char *fmt, ...);
916void trace_printk_seq(struct trace_seq *s);
917enum print_line_t print_trace_line(struct trace_iterator *iter);
918
919extern char trace_find_mark(unsigned long long duration);
920
921struct ftrace_hash;
922
923struct ftrace_mod_load {
924 struct list_head list;
925 char *func;
926 char *module;
927 int enable;
928};
929
930enum {
931 FTRACE_HASH_FL_MOD = (1 << 0),
932};
933
934struct ftrace_hash {
935 unsigned long size_bits;
936 struct hlist_head *buckets;
937 unsigned long count;
938 unsigned long flags;
939 struct rcu_head rcu;
940};
941
942struct ftrace_func_entry *
943ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
944
945static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
946{
947 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
948}
949
950/* Standard output formatting function used for function return traces */
951#ifdef CONFIG_FUNCTION_GRAPH_TRACER
952
953/* Flag options */
954#define TRACE_GRAPH_PRINT_OVERRUN 0x1
955#define TRACE_GRAPH_PRINT_CPU 0x2
956#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
957#define TRACE_GRAPH_PRINT_PROC 0x8
958#define TRACE_GRAPH_PRINT_DURATION 0x10
959#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
960#define TRACE_GRAPH_PRINT_REL_TIME 0x40
961#define TRACE_GRAPH_PRINT_IRQS 0x80
962#define TRACE_GRAPH_PRINT_TAIL 0x100
963#define TRACE_GRAPH_SLEEP_TIME 0x200
964#define TRACE_GRAPH_GRAPH_TIME 0x400
965#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
966#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
967
968extern void ftrace_graph_sleep_time_control(bool enable);
969
970#ifdef CONFIG_FUNCTION_PROFILER
971extern void ftrace_graph_graph_time_control(bool enable);
972#else
973static inline void ftrace_graph_graph_time_control(bool enable) { }
974#endif
975
976extern enum print_line_t
977print_graph_function_flags(struct trace_iterator *iter, u32 flags);
978extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
979extern void
980trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
981extern void graph_trace_open(struct trace_iterator *iter);
982extern void graph_trace_close(struct trace_iterator *iter);
983extern int __trace_graph_entry(struct trace_array *tr,
984 struct ftrace_graph_ent *trace,
985 unsigned long flags, int pc);
986extern void __trace_graph_return(struct trace_array *tr,
987 struct ftrace_graph_ret *trace,
988 unsigned long flags, int pc);
989
990#ifdef CONFIG_DYNAMIC_FTRACE
991extern struct ftrace_hash __rcu *ftrace_graph_hash;
992extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
993
994static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
995{
996 unsigned long addr = trace->func;
997 int ret = 0;
998 struct ftrace_hash *hash;
999
1000 preempt_disable_notrace();
1001
1002 /*
1003 * Have to open code "rcu_dereference_sched()" because the
1004 * function graph tracer can be called when RCU is not
1005 * "watching".
1006 * Protected with schedule_on_each_cpu(ftrace_sync)
1007 */
1008 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
1009
1010 if (ftrace_hash_empty(hash)) {
1011 ret = 1;
1012 goto out;
1013 }
1014
1015 if (ftrace_lookup_ip(hash, addr)) {
1016
1017 /*
1018 * This needs to be cleared on the return functions
1019 * when the depth is zero.
1020 */
1021 trace_recursion_set(TRACE_GRAPH_BIT);
1022 trace_recursion_set_depth(trace->depth);
1023
1024 /*
1025 * If no irqs are to be traced, but a set_graph_function
1026 * is set, and called by an interrupt handler, we still
1027 * want to trace it.
1028 */
1029 if (in_irq())
1030 trace_recursion_set(TRACE_IRQ_BIT);
1031 else
1032 trace_recursion_clear(TRACE_IRQ_BIT);
1033 ret = 1;
1034 }
1035
1036out:
1037 preempt_enable_notrace();
1038 return ret;
1039}
1040
1041static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
1042{
1043 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
1044 trace->depth == trace_recursion_depth())
1045 trace_recursion_clear(TRACE_GRAPH_BIT);
1046}
1047
1048static inline int ftrace_graph_notrace_addr(unsigned long addr)
1049{
1050 int ret = 0;
1051 struct ftrace_hash *notrace_hash;
1052
1053 preempt_disable_notrace();
1054
1055 /*
1056 * Have to open code "rcu_dereference_sched()" because the
1057 * function graph tracer can be called when RCU is not
1058 * "watching".
1059 * Protected with schedule_on_each_cpu(ftrace_sync)
1060 */
1061 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1062 !preemptible());
1063
1064 if (ftrace_lookup_ip(notrace_hash, addr))
1065 ret = 1;
1066
1067 preempt_enable_notrace();
1068 return ret;
1069}
1070#else
1071static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
1072{
1073 return 1;
1074}
1075
1076static inline int ftrace_graph_notrace_addr(unsigned long addr)
1077{
1078 return 0;
1079}
1080static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
1081{ }
1082#endif /* CONFIG_DYNAMIC_FTRACE */
1083
1084extern unsigned int fgraph_max_depth;
1085
1086static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
1087{
1088 /* trace it when it is-nested-in or is a function enabled. */
1089 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
1090 ftrace_graph_addr(trace)) ||
1091 (trace->depth < 0) ||
1092 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
1093}
1094
1095#else /* CONFIG_FUNCTION_GRAPH_TRACER */
1096static inline enum print_line_t
1097print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1098{
1099 return TRACE_TYPE_UNHANDLED;
1100}
1101#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1102
1103extern struct list_head ftrace_pids;
1104
1105#ifdef CONFIG_FUNCTION_TRACER
1106
1107#define FTRACE_PID_IGNORE -1
1108#define FTRACE_PID_TRACE -2
1109
1110struct ftrace_func_command {
1111 struct list_head list;
1112 char *name;
1113 int (*func)(struct trace_array *tr,
1114 struct ftrace_hash *hash,
1115 char *func, char *cmd,
1116 char *params, int enable);
1117};
1118extern bool ftrace_filter_param __initdata;
1119static inline int ftrace_trace_task(struct trace_array *tr)
1120{
1121 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1122 FTRACE_PID_IGNORE;
1123}
1124extern int ftrace_is_dead(void);
1125int ftrace_create_function_files(struct trace_array *tr,
1126 struct dentry *parent);
1127void ftrace_destroy_function_files(struct trace_array *tr);
1128void ftrace_init_global_array_ops(struct trace_array *tr);
1129void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1130void ftrace_reset_array_ops(struct trace_array *tr);
1131void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1132void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1133 struct dentry *d_tracer);
1134void ftrace_clear_pids(struct trace_array *tr);
1135int init_function_trace(void);
1136void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1137#else
1138static inline int ftrace_trace_task(struct trace_array *tr)
1139{
1140 return 1;
1141}
1142static inline int ftrace_is_dead(void) { return 0; }
1143static inline int
1144ftrace_create_function_files(struct trace_array *tr,
1145 struct dentry *parent)
1146{
1147 return 0;
1148}
1149static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1150static inline __init void
1151ftrace_init_global_array_ops(struct trace_array *tr) { }
1152static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1153static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1154static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1155static inline void ftrace_clear_pids(struct trace_array *tr) { }
1156static inline int init_function_trace(void) { return 0; }
1157static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1158/* ftace_func_t type is not defined, use macro instead of static inline */
1159#define ftrace_init_array_ops(tr, func) do { } while (0)
1160#endif /* CONFIG_FUNCTION_TRACER */
1161
1162#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1163
1164struct ftrace_probe_ops {
1165 void (*func)(unsigned long ip,
1166 unsigned long parent_ip,
1167 struct trace_array *tr,
1168 struct ftrace_probe_ops *ops,
1169 void *data);
1170 int (*init)(struct ftrace_probe_ops *ops,
1171 struct trace_array *tr,
1172 unsigned long ip, void *init_data,
1173 void **data);
1174 void (*free)(struct ftrace_probe_ops *ops,
1175 struct trace_array *tr,
1176 unsigned long ip, void *data);
1177 int (*print)(struct seq_file *m,
1178 unsigned long ip,
1179 struct ftrace_probe_ops *ops,
1180 void *data);
1181};
1182
1183struct ftrace_func_mapper;
1184typedef int (*ftrace_mapper_func)(void *data);
1185
1186struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1187void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1188 unsigned long ip);
1189int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1190 unsigned long ip, void *data);
1191void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1192 unsigned long ip);
1193void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1194 ftrace_mapper_func free_func);
1195
1196extern int
1197register_ftrace_function_probe(char *glob, struct trace_array *tr,
1198 struct ftrace_probe_ops *ops, void *data);
1199extern int
1200unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1201 struct ftrace_probe_ops *ops);
1202extern void clear_ftrace_function_probes(struct trace_array *tr);
1203
1204int register_ftrace_command(struct ftrace_func_command *cmd);
1205int unregister_ftrace_command(struct ftrace_func_command *cmd);
1206
1207void ftrace_create_filter_files(struct ftrace_ops *ops,
1208 struct dentry *parent);
1209void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1210
1211extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1212 int len, int reset);
1213extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1214 int len, int reset);
1215#else
1216struct ftrace_func_command;
1217
1218static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1219{
1220 return -EINVAL;
1221}
1222static inline __init int unregister_ftrace_command(char *cmd_name)
1223{
1224 return -EINVAL;
1225}
1226static inline void clear_ftrace_function_probes(struct trace_array *tr)
1227{
1228}
1229
1230/*
1231 * The ops parameter passed in is usually undefined.
1232 * This must be a macro.
1233 */
1234#define ftrace_create_filter_files(ops, parent) do { } while (0)
1235#define ftrace_destroy_filter_files(ops) do { } while (0)
1236#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1237
1238bool ftrace_event_is_function(struct trace_event_call *call);
1239
1240/*
1241 * struct trace_parser - servers for reading the user input separated by spaces
1242 * @cont: set if the input is not complete - no final space char was found
1243 * @buffer: holds the parsed user input
1244 * @idx: user input length
1245 * @size: buffer size
1246 */
1247struct trace_parser {
1248 bool cont;
1249 char *buffer;
1250 unsigned idx;
1251 unsigned size;
1252};
1253
1254static inline bool trace_parser_loaded(struct trace_parser *parser)
1255{
1256 return (parser->idx != 0);
1257}
1258
1259static inline bool trace_parser_cont(struct trace_parser *parser)
1260{
1261 return parser->cont;
1262}
1263
1264static inline void trace_parser_clear(struct trace_parser *parser)
1265{
1266 parser->cont = false;
1267 parser->idx = 0;
1268}
1269
1270extern int trace_parser_get_init(struct trace_parser *parser, int size);
1271extern void trace_parser_put(struct trace_parser *parser);
1272extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1273 size_t cnt, loff_t *ppos);
1274
1275/*
1276 * Only create function graph options if function graph is configured.
1277 */
1278#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1279# define FGRAPH_FLAGS \
1280 C(DISPLAY_GRAPH, "display-graph"),
1281#else
1282# define FGRAPH_FLAGS
1283#endif
1284
1285#ifdef CONFIG_BRANCH_TRACER
1286# define BRANCH_FLAGS \
1287 C(BRANCH, "branch"),
1288#else
1289# define BRANCH_FLAGS
1290#endif
1291
1292#ifdef CONFIG_FUNCTION_TRACER
1293# define FUNCTION_FLAGS \
1294 C(FUNCTION, "function-trace"), \
1295 C(FUNC_FORK, "function-fork"),
1296# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1297#else
1298# define FUNCTION_FLAGS
1299# define FUNCTION_DEFAULT_FLAGS 0UL
1300# define TRACE_ITER_FUNC_FORK 0UL
1301#endif
1302
1303#ifdef CONFIG_STACKTRACE
1304# define STACK_FLAGS \
1305 C(STACKTRACE, "stacktrace"),
1306#else
1307# define STACK_FLAGS
1308#endif
1309
1310/*
1311 * trace_iterator_flags is an enumeration that defines bit
1312 * positions into trace_flags that controls the output.
1313 *
1314 * NOTE: These bits must match the trace_options array in
1315 * trace.c (this macro guarantees it).
1316 */
1317#define TRACE_FLAGS \
1318 C(PRINT_PARENT, "print-parent"), \
1319 C(SYM_OFFSET, "sym-offset"), \
1320 C(SYM_ADDR, "sym-addr"), \
1321 C(VERBOSE, "verbose"), \
1322 C(RAW, "raw"), \
1323 C(HEX, "hex"), \
1324 C(BIN, "bin"), \
1325 C(BLOCK, "block"), \
1326 C(PRINTK, "trace_printk"), \
1327 C(ANNOTATE, "annotate"), \
1328 C(USERSTACKTRACE, "userstacktrace"), \
1329 C(SYM_USEROBJ, "sym-userobj"), \
1330 C(PRINTK_MSGONLY, "printk-msg-only"), \
1331 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1332 C(LATENCY_FMT, "latency-format"), \
1333 C(RECORD_CMD, "record-cmd"), \
1334 C(RECORD_TGID, "record-tgid"), \
1335 C(OVERWRITE, "overwrite"), \
1336 C(STOP_ON_FREE, "disable_on_free"), \
1337 C(IRQ_INFO, "irq-info"), \
1338 C(MARKERS, "markers"), \
1339 C(EVENT_FORK, "event-fork"), \
1340 C(PAUSE_ON_TRACE, "pause-on-trace"), \
1341 FUNCTION_FLAGS \
1342 FGRAPH_FLAGS \
1343 STACK_FLAGS \
1344 BRANCH_FLAGS
1345
1346/*
1347 * By defining C, we can make TRACE_FLAGS a list of bit names
1348 * that will define the bits for the flag masks.
1349 */
1350#undef C
1351#define C(a, b) TRACE_ITER_##a##_BIT
1352
1353enum trace_iterator_bits {
1354 TRACE_FLAGS
1355 /* Make sure we don't go more than we have bits for */
1356 TRACE_ITER_LAST_BIT
1357};
1358
1359/*
1360 * By redefining C, we can make TRACE_FLAGS a list of masks that
1361 * use the bits as defined above.
1362 */
1363#undef C
1364#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1365
1366enum trace_iterator_flags { TRACE_FLAGS };
1367
1368/*
1369 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1370 * control the output of kernel symbols.
1371 */
1372#define TRACE_ITER_SYM_MASK \
1373 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1374
1375extern struct tracer nop_trace;
1376
1377#ifdef CONFIG_BRANCH_TRACER
1378extern int enable_branch_tracing(struct trace_array *tr);
1379extern void disable_branch_tracing(void);
1380static inline int trace_branch_enable(struct trace_array *tr)
1381{
1382 if (tr->trace_flags & TRACE_ITER_BRANCH)
1383 return enable_branch_tracing(tr);
1384 return 0;
1385}
1386static inline void trace_branch_disable(void)
1387{
1388 /* due to races, always disable */
1389 disable_branch_tracing();
1390}
1391#else
1392static inline int trace_branch_enable(struct trace_array *tr)
1393{
1394 return 0;
1395}
1396static inline void trace_branch_disable(void)
1397{
1398}
1399#endif /* CONFIG_BRANCH_TRACER */
1400
1401/* set ring buffers to default size if not already done so */
1402int tracing_update_buffers(void);
1403
1404struct ftrace_event_field {
1405 struct list_head link;
1406 const char *name;
1407 const char *type;
1408 int filter_type;
1409 int offset;
1410 int size;
1411 int is_signed;
1412};
1413
1414struct prog_entry;
1415
1416struct event_filter {
1417 struct prog_entry __rcu *prog;
1418 char *filter_string;
1419};
1420
1421struct event_subsystem {
1422 struct list_head list;
1423 const char *name;
1424 struct event_filter *filter;
1425 int ref_count;
1426};
1427
1428struct trace_subsystem_dir {
1429 struct list_head list;
1430 struct event_subsystem *subsystem;
1431 struct trace_array *tr;
1432 struct dentry *entry;
1433 int ref_count;
1434 int nr_events;
1435};
1436
1437extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1438 struct trace_buffer *buffer,
1439 struct ring_buffer_event *event);
1440
1441void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1442 struct trace_buffer *buffer,
1443 struct ring_buffer_event *event,
1444 unsigned long flags, int pc,
1445 struct pt_regs *regs);
1446
1447static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1448 struct trace_buffer *buffer,
1449 struct ring_buffer_event *event,
1450 unsigned long flags, int pc)
1451{
1452 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1453}
1454
1455DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1456DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1457void trace_buffered_event_disable(void);
1458void trace_buffered_event_enable(void);
1459
1460static inline void
1461__trace_event_discard_commit(struct trace_buffer *buffer,
1462 struct ring_buffer_event *event)
1463{
1464 if (this_cpu_read(trace_buffered_event) == event) {
1465 /* Simply release the temp buffer */
1466 this_cpu_dec(trace_buffered_event_cnt);
1467 return;
1468 }
1469 ring_buffer_discard_commit(buffer, event);
1470}
1471
1472/*
1473 * Helper function for event_trigger_unlock_commit{_regs}().
1474 * If there are event triggers attached to this event that requires
1475 * filtering against its fields, then they wil be called as the
1476 * entry already holds the field information of the current event.
1477 *
1478 * It also checks if the event should be discarded or not.
1479 * It is to be discarded if the event is soft disabled and the
1480 * event was only recorded to process triggers, or if the event
1481 * filter is active and this event did not match the filters.
1482 *
1483 * Returns true if the event is discarded, false otherwise.
1484 */
1485static inline bool
1486__event_trigger_test_discard(struct trace_event_file *file,
1487 struct trace_buffer *buffer,
1488 struct ring_buffer_event *event,
1489 void *entry,
1490 enum event_trigger_type *tt)
1491{
1492 unsigned long eflags = file->flags;
1493
1494 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1495 *tt = event_triggers_call(file, entry, event);
1496
1497 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1498 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1499 !filter_match_preds(file->filter, entry))) {
1500 __trace_event_discard_commit(buffer, event);
1501 return true;
1502 }
1503
1504 return false;
1505}
1506
1507/**
1508 * event_trigger_unlock_commit - handle triggers and finish event commit
1509 * @file: The file pointer assoctiated to the event
1510 * @buffer: The ring buffer that the event is being written to
1511 * @event: The event meta data in the ring buffer
1512 * @entry: The event itself
1513 * @irq_flags: The state of the interrupts at the start of the event
1514 * @pc: The state of the preempt count at the start of the event.
1515 *
1516 * This is a helper function to handle triggers that require data
1517 * from the event itself. It also tests the event against filters and
1518 * if the event is soft disabled and should be discarded.
1519 */
1520static inline void
1521event_trigger_unlock_commit(struct trace_event_file *file,
1522 struct trace_buffer *buffer,
1523 struct ring_buffer_event *event,
1524 void *entry, unsigned long irq_flags, int pc)
1525{
1526 enum event_trigger_type tt = ETT_NONE;
1527
1528 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1529 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1530
1531 if (tt)
1532 event_triggers_post_call(file, tt);
1533}
1534
1535/**
1536 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1537 * @file: The file pointer assoctiated to the event
1538 * @buffer: The ring buffer that the event is being written to
1539 * @event: The event meta data in the ring buffer
1540 * @entry: The event itself
1541 * @irq_flags: The state of the interrupts at the start of the event
1542 * @pc: The state of the preempt count at the start of the event.
1543 *
1544 * This is a helper function to handle triggers that require data
1545 * from the event itself. It also tests the event against filters and
1546 * if the event is soft disabled and should be discarded.
1547 *
1548 * Same as event_trigger_unlock_commit() but calls
1549 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1550 */
1551static inline void
1552event_trigger_unlock_commit_regs(struct trace_event_file *file,
1553 struct trace_buffer *buffer,
1554 struct ring_buffer_event *event,
1555 void *entry, unsigned long irq_flags, int pc,
1556 struct pt_regs *regs)
1557{
1558 enum event_trigger_type tt = ETT_NONE;
1559
1560 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1561 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1562 irq_flags, pc, regs);
1563
1564 if (tt)
1565 event_triggers_post_call(file, tt);
1566}
1567
1568#define FILTER_PRED_INVALID ((unsigned short)-1)
1569#define FILTER_PRED_IS_RIGHT (1 << 15)
1570#define FILTER_PRED_FOLD (1 << 15)
1571
1572/*
1573 * The max preds is the size of unsigned short with
1574 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1575 * and FOLD flags. The other is reserved.
1576 *
1577 * 2^14 preds is way more than enough.
1578 */
1579#define MAX_FILTER_PRED 16384
1580
1581struct filter_pred;
1582struct regex;
1583
1584typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1585
1586typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1587
1588enum regex_type {
1589 MATCH_FULL = 0,
1590 MATCH_FRONT_ONLY,
1591 MATCH_MIDDLE_ONLY,
1592 MATCH_END_ONLY,
1593 MATCH_GLOB,
1594 MATCH_INDEX,
1595};
1596
1597struct regex {
1598 char pattern[MAX_FILTER_STR_VAL];
1599 int len;
1600 int field_len;
1601 regex_match_func match;
1602};
1603
1604struct filter_pred {
1605 filter_pred_fn_t fn;
1606 u64 val;
1607 struct regex regex;
1608 unsigned short *ops;
1609 struct ftrace_event_field *field;
1610 int offset;
1611 int not;
1612 int op;
1613};
1614
1615static inline bool is_string_field(struct ftrace_event_field *field)
1616{
1617 return field->filter_type == FILTER_DYN_STRING ||
1618 field->filter_type == FILTER_STATIC_STRING ||
1619 field->filter_type == FILTER_PTR_STRING ||
1620 field->filter_type == FILTER_COMM;
1621}
1622
1623static inline bool is_function_field(struct ftrace_event_field *field)
1624{
1625 return field->filter_type == FILTER_TRACE_FN;
1626}
1627
1628extern enum regex_type
1629filter_parse_regex(char *buff, int len, char **search, int *not);
1630extern void print_event_filter(struct trace_event_file *file,
1631 struct trace_seq *s);
1632extern int apply_event_filter(struct trace_event_file *file,
1633 char *filter_string);
1634extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1635 char *filter_string);
1636extern void print_subsystem_event_filter(struct event_subsystem *system,
1637 struct trace_seq *s);
1638extern int filter_assign_type(const char *type);
1639extern int create_event_filter(struct trace_array *tr,
1640 struct trace_event_call *call,
1641 char *filter_str, bool set_str,
1642 struct event_filter **filterp);
1643extern void free_event_filter(struct event_filter *filter);
1644
1645struct ftrace_event_field *
1646trace_find_event_field(struct trace_event_call *call, char *name);
1647
1648extern void trace_event_enable_cmd_record(bool enable);
1649extern void trace_event_enable_tgid_record(bool enable);
1650
1651extern int event_trace_init(void);
1652extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1653extern int event_trace_del_tracer(struct trace_array *tr);
1654
1655extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1656 const char *system,
1657 const char *event);
1658extern struct trace_event_file *find_event_file(struct trace_array *tr,
1659 const char *system,
1660 const char *event);
1661
1662static inline void *event_file_data(struct file *filp)
1663{
1664 return READ_ONCE(file_inode(filp)->i_private);
1665}
1666
1667extern struct mutex event_mutex;
1668extern struct list_head ftrace_events;
1669
1670extern const struct file_operations event_trigger_fops;
1671extern const struct file_operations event_hist_fops;
1672extern const struct file_operations event_hist_debug_fops;
1673extern const struct file_operations event_inject_fops;
1674
1675#ifdef CONFIG_HIST_TRIGGERS
1676extern int register_trigger_hist_cmd(void);
1677extern int register_trigger_hist_enable_disable_cmds(void);
1678#else
1679static inline int register_trigger_hist_cmd(void) { return 0; }
1680static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1681#endif
1682
1683extern int register_trigger_cmds(void);
1684extern void clear_event_triggers(struct trace_array *tr);
1685
1686struct event_trigger_data {
1687 unsigned long count;
1688 int ref;
1689 struct event_trigger_ops *ops;
1690 struct event_command *cmd_ops;
1691 struct event_filter __rcu *filter;
1692 char *filter_str;
1693 void *private_data;
1694 bool paused;
1695 bool paused_tmp;
1696 struct list_head list;
1697 char *name;
1698 struct list_head named_list;
1699 struct event_trigger_data *named_data;
1700};
1701
1702/* Avoid typos */
1703#define ENABLE_EVENT_STR "enable_event"
1704#define DISABLE_EVENT_STR "disable_event"
1705#define ENABLE_HIST_STR "enable_hist"
1706#define DISABLE_HIST_STR "disable_hist"
1707
1708struct enable_trigger_data {
1709 struct trace_event_file *file;
1710 bool enable;
1711 bool hist;
1712};
1713
1714extern int event_enable_trigger_print(struct seq_file *m,
1715 struct event_trigger_ops *ops,
1716 struct event_trigger_data *data);
1717extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1718 struct event_trigger_data *data);
1719extern int event_enable_trigger_func(struct event_command *cmd_ops,
1720 struct trace_event_file *file,
1721 char *glob, char *cmd, char *param);
1722extern int event_enable_register_trigger(char *glob,
1723 struct event_trigger_ops *ops,
1724 struct event_trigger_data *data,
1725 struct trace_event_file *file);
1726extern void event_enable_unregister_trigger(char *glob,
1727 struct event_trigger_ops *ops,
1728 struct event_trigger_data *test,
1729 struct trace_event_file *file);
1730extern void trigger_data_free(struct event_trigger_data *data);
1731extern int event_trigger_init(struct event_trigger_ops *ops,
1732 struct event_trigger_data *data);
1733extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1734 int trigger_enable);
1735extern void update_cond_flag(struct trace_event_file *file);
1736extern int set_trigger_filter(char *filter_str,
1737 struct event_trigger_data *trigger_data,
1738 struct trace_event_file *file);
1739extern struct event_trigger_data *find_named_trigger(const char *name);
1740extern bool is_named_trigger(struct event_trigger_data *test);
1741extern int save_named_trigger(const char *name,
1742 struct event_trigger_data *data);
1743extern void del_named_trigger(struct event_trigger_data *data);
1744extern void pause_named_trigger(struct event_trigger_data *data);
1745extern void unpause_named_trigger(struct event_trigger_data *data);
1746extern void set_named_trigger_data(struct event_trigger_data *data,
1747 struct event_trigger_data *named_data);
1748extern struct event_trigger_data *
1749get_named_trigger_data(struct event_trigger_data *data);
1750extern int register_event_command(struct event_command *cmd);
1751extern int unregister_event_command(struct event_command *cmd);
1752extern int register_trigger_hist_enable_disable_cmds(void);
1753
1754/**
1755 * struct event_trigger_ops - callbacks for trace event triggers
1756 *
1757 * The methods in this structure provide per-event trigger hooks for
1758 * various trigger operations.
1759 *
1760 * All the methods below, except for @init() and @free(), must be
1761 * implemented.
1762 *
1763 * @func: The trigger 'probe' function called when the triggering
1764 * event occurs. The data passed into this callback is the data
1765 * that was supplied to the event_command @reg() function that
1766 * registered the trigger (see struct event_command) along with
1767 * the trace record, rec.
1768 *
1769 * @init: An optional initialization function called for the trigger
1770 * when the trigger is registered (via the event_command reg()
1771 * function). This can be used to perform per-trigger
1772 * initialization such as incrementing a per-trigger reference
1773 * count, for instance. This is usually implemented by the
1774 * generic utility function @event_trigger_init() (see
1775 * trace_event_triggers.c).
1776 *
1777 * @free: An optional de-initialization function called for the
1778 * trigger when the trigger is unregistered (via the
1779 * event_command @reg() function). This can be used to perform
1780 * per-trigger de-initialization such as decrementing a
1781 * per-trigger reference count and freeing corresponding trigger
1782 * data, for instance. This is usually implemented by the
1783 * generic utility function @event_trigger_free() (see
1784 * trace_event_triggers.c).
1785 *
1786 * @print: The callback function invoked to have the trigger print
1787 * itself. This is usually implemented by a wrapper function
1788 * that calls the generic utility function @event_trigger_print()
1789 * (see trace_event_triggers.c).
1790 */
1791struct event_trigger_ops {
1792 void (*func)(struct event_trigger_data *data,
1793 void *rec,
1794 struct ring_buffer_event *rbe);
1795 int (*init)(struct event_trigger_ops *ops,
1796 struct event_trigger_data *data);
1797 void (*free)(struct event_trigger_ops *ops,
1798 struct event_trigger_data *data);
1799 int (*print)(struct seq_file *m,
1800 struct event_trigger_ops *ops,
1801 struct event_trigger_data *data);
1802};
1803
1804/**
1805 * struct event_command - callbacks and data members for event commands
1806 *
1807 * Event commands are invoked by users by writing the command name
1808 * into the 'trigger' file associated with a trace event. The
1809 * parameters associated with a specific invocation of an event
1810 * command are used to create an event trigger instance, which is
1811 * added to the list of trigger instances associated with that trace
1812 * event. When the event is hit, the set of triggers associated with
1813 * that event is invoked.
1814 *
1815 * The data members in this structure provide per-event command data
1816 * for various event commands.
1817 *
1818 * All the data members below, except for @post_trigger, must be set
1819 * for each event command.
1820 *
1821 * @name: The unique name that identifies the event command. This is
1822 * the name used when setting triggers via trigger files.
1823 *
1824 * @trigger_type: A unique id that identifies the event command
1825 * 'type'. This value has two purposes, the first to ensure that
1826 * only one trigger of the same type can be set at a given time
1827 * for a particular event e.g. it doesn't make sense to have both
1828 * a traceon and traceoff trigger attached to a single event at
1829 * the same time, so traceon and traceoff have the same type
1830 * though they have different names. The @trigger_type value is
1831 * also used as a bit value for deferring the actual trigger
1832 * action until after the current event is finished. Some
1833 * commands need to do this if they themselves log to the trace
1834 * buffer (see the @post_trigger() member below). @trigger_type
1835 * values are defined by adding new values to the trigger_type
1836 * enum in include/linux/trace_events.h.
1837 *
1838 * @flags: See the enum event_command_flags below.
1839 *
1840 * All the methods below, except for @set_filter() and @unreg_all(),
1841 * must be implemented.
1842 *
1843 * @func: The callback function responsible for parsing and
1844 * registering the trigger written to the 'trigger' file by the
1845 * user. It allocates the trigger instance and registers it with
1846 * the appropriate trace event. It makes use of the other
1847 * event_command callback functions to orchestrate this, and is
1848 * usually implemented by the generic utility function
1849 * @event_trigger_callback() (see trace_event_triggers.c).
1850 *
1851 * @reg: Adds the trigger to the list of triggers associated with the
1852 * event, and enables the event trigger itself, after
1853 * initializing it (via the event_trigger_ops @init() function).
1854 * This is also where commands can use the @trigger_type value to
1855 * make the decision as to whether or not multiple instances of
1856 * the trigger should be allowed. This is usually implemented by
1857 * the generic utility function @register_trigger() (see
1858 * trace_event_triggers.c).
1859 *
1860 * @unreg: Removes the trigger from the list of triggers associated
1861 * with the event, and disables the event trigger itself, after
1862 * initializing it (via the event_trigger_ops @free() function).
1863 * This is usually implemented by the generic utility function
1864 * @unregister_trigger() (see trace_event_triggers.c).
1865 *
1866 * @unreg_all: An optional function called to remove all the triggers
1867 * from the list of triggers associated with the event. Called
1868 * when a trigger file is opened in truncate mode.
1869 *
1870 * @set_filter: An optional function called to parse and set a filter
1871 * for the trigger. If no @set_filter() method is set for the
1872 * event command, filters set by the user for the command will be
1873 * ignored. This is usually implemented by the generic utility
1874 * function @set_trigger_filter() (see trace_event_triggers.c).
1875 *
1876 * @get_trigger_ops: The callback function invoked to retrieve the
1877 * event_trigger_ops implementation associated with the command.
1878 */
1879struct event_command {
1880 struct list_head list;
1881 char *name;
1882 enum event_trigger_type trigger_type;
1883 int flags;
1884 int (*func)(struct event_command *cmd_ops,
1885 struct trace_event_file *file,
1886 char *glob, char *cmd, char *params);
1887 int (*reg)(char *glob,
1888 struct event_trigger_ops *ops,
1889 struct event_trigger_data *data,
1890 struct trace_event_file *file);
1891 void (*unreg)(char *glob,
1892 struct event_trigger_ops *ops,
1893 struct event_trigger_data *data,
1894 struct trace_event_file *file);
1895 void (*unreg_all)(struct trace_event_file *file);
1896 int (*set_filter)(char *filter_str,
1897 struct event_trigger_data *data,
1898 struct trace_event_file *file);
1899 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1900};
1901
1902/**
1903 * enum event_command_flags - flags for struct event_command
1904 *
1905 * @POST_TRIGGER: A flag that says whether or not this command needs
1906 * to have its action delayed until after the current event has
1907 * been closed. Some triggers need to avoid being invoked while
1908 * an event is currently in the process of being logged, since
1909 * the trigger may itself log data into the trace buffer. Thus
1910 * we make sure the current event is committed before invoking
1911 * those triggers. To do that, the trigger invocation is split
1912 * in two - the first part checks the filter using the current
1913 * trace record; if a command has the @post_trigger flag set, it
1914 * sets a bit for itself in the return value, otherwise it
1915 * directly invokes the trigger. Once all commands have been
1916 * either invoked or set their return flag, the current record is
1917 * either committed or discarded. At that point, if any commands
1918 * have deferred their triggers, those commands are finally
1919 * invoked following the close of the current event. In other
1920 * words, if the event_trigger_ops @func() probe implementation
1921 * itself logs to the trace buffer, this flag should be set,
1922 * otherwise it can be left unspecified.
1923 *
1924 * @NEEDS_REC: A flag that says whether or not this command needs
1925 * access to the trace record in order to perform its function,
1926 * regardless of whether or not it has a filter associated with
1927 * it (filters make a trigger require access to the trace record
1928 * but are not always present).
1929 */
1930enum event_command_flags {
1931 EVENT_CMD_FL_POST_TRIGGER = 1,
1932 EVENT_CMD_FL_NEEDS_REC = 2,
1933};
1934
1935static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1936{
1937 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1938}
1939
1940static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1941{
1942 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1943}
1944
1945extern int trace_event_enable_disable(struct trace_event_file *file,
1946 int enable, int soft_disable);
1947extern int tracing_alloc_snapshot(void);
1948extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1949extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1950
1951extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1952extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1953
1954extern const char *__start___trace_bprintk_fmt[];
1955extern const char *__stop___trace_bprintk_fmt[];
1956
1957extern const char *__start___tracepoint_str[];
1958extern const char *__stop___tracepoint_str[];
1959
1960void trace_printk_control(bool enabled);
1961void trace_printk_start_comm(void);
1962int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1963int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1964
1965/* Used from boot time tracer */
1966extern int trace_set_options(struct trace_array *tr, char *option);
1967extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1968extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1969 unsigned long size, int cpu_id);
1970extern int tracing_set_cpumask(struct trace_array *tr,
1971 cpumask_var_t tracing_cpumask_new);
1972
1973
1974#define MAX_EVENT_NAME_LEN 64
1975
1976extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1977extern ssize_t trace_parse_run_command(struct file *file,
1978 const char __user *buffer, size_t count, loff_t *ppos,
1979 int (*createfn)(int, char**));
1980
1981extern unsigned int err_pos(char *cmd, const char *str);
1982extern void tracing_log_err(struct trace_array *tr,
1983 const char *loc, const char *cmd,
1984 const char **errs, u8 type, u8 pos);
1985
1986/*
1987 * Normal trace_printk() and friends allocates special buffers
1988 * to do the manipulation, as well as saves the print formats
1989 * into sections to display. But the trace infrastructure wants
1990 * to use these without the added overhead at the price of being
1991 * a bit slower (used mainly for warnings, where we don't care
1992 * about performance). The internal_trace_puts() is for such
1993 * a purpose.
1994 */
1995#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1996
1997#undef FTRACE_ENTRY
1998#define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
1999 extern struct trace_event_call \
2000 __aligned(4) event_##call;
2001#undef FTRACE_ENTRY_DUP
2002#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
2003 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2004#undef FTRACE_ENTRY_PACKED
2005#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2006 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2007
2008#include "trace_entries.h"
2009
2010#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2011int perf_ftrace_event_register(struct trace_event_call *call,
2012 enum trace_reg type, void *data);
2013#else
2014#define perf_ftrace_event_register NULL
2015#endif
2016
2017#ifdef CONFIG_FTRACE_SYSCALLS
2018void init_ftrace_syscalls(void);
2019const char *get_syscall_name(int syscall);
2020#else
2021static inline void init_ftrace_syscalls(void) { }
2022static inline const char *get_syscall_name(int syscall)
2023{
2024 return NULL;
2025}
2026#endif
2027
2028#ifdef CONFIG_EVENT_TRACING
2029void trace_event_init(void);
2030void trace_event_eval_update(struct trace_eval_map **map, int len);
2031/* Used from boot time tracer */
2032extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2033extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2034#else
2035static inline void __init trace_event_init(void) { }
2036static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2037#endif
2038
2039#ifdef CONFIG_TRACER_SNAPSHOT
2040void tracing_snapshot_instance(struct trace_array *tr);
2041int tracing_alloc_snapshot_instance(struct trace_array *tr);
2042#else
2043static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2044static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2045{
2046 return 0;
2047}
2048#endif
2049
2050#ifdef CONFIG_PREEMPT_TRACER
2051void tracer_preempt_on(unsigned long a0, unsigned long a1);
2052void tracer_preempt_off(unsigned long a0, unsigned long a1);
2053#else
2054static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2055static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2056#endif
2057#ifdef CONFIG_IRQSOFF_TRACER
2058void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2059void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2060#else
2061static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2062static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2063#endif
2064
2065extern struct trace_iterator *tracepoint_print_iter;
2066
2067/*
2068 * Reset the state of the trace_iterator so that it can read consumed data.
2069 * Normally, the trace_iterator is used for reading the data when it is not
2070 * consumed, and must retain state.
2071 */
2072static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2073{
2074 const size_t offset = offsetof(struct trace_iterator, seq);
2075
2076 /*
2077 * Keep gcc from complaining about overwriting more than just one
2078 * member in the structure.
2079 */
2080 memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
2081
2082 iter->pos = -1;
2083}
2084
2085#endif /* _LINUX_KERNEL_TRACE_H */