1  // SPDX-License-Identifier: GPL-2.0
2  
3  #ifndef _LINUX_KERNEL_TRACE_H
4  #define _LINUX_KERNEL_TRACE_H
5  
6  #include <linux/fs.h>
7  #include <linux/atomic.h>
8  #include <linux/sched.h>
9  #include <linux/clocksource.h>
10  #include <linux/ring_buffer.h>
11  #include <linux/mmiotrace.h>
12  #include <linux/tracepoint.h>
13  #include <linux/ftrace.h>
14  #include <linux/trace.h>
15  #include <linux/hw_breakpoint.h>
16  #include <linux/trace_seq.h>
17  #include <linux/trace_events.h>
18  #include <linux/compiler.h>
19  #include <linux/glob.h>
20  #include <linux/irq_work.h>
21  #include <linux/workqueue.h>
22  #include <linux/ctype.h>
23  #include <linux/once_lite.h>
24  
25  #include "pid_list.h"
26  
27  #ifdef CONFIG_FTRACE_SYSCALLS
28  #include <asm/unistd.h>		/* For NR_syscalls	     */
29  #include <asm/syscall.h>	/* some archs define it here */
30  #endif
31  
32  #define TRACE_MODE_WRITE	0640
33  #define TRACE_MODE_READ		0440
34  
35  enum trace_type {
36  	__TRACE_FIRST_TYPE = 0,
37  
38  	TRACE_FN,
39  	TRACE_CTX,
40  	TRACE_WAKE,
41  	TRACE_STACK,
42  	TRACE_PRINT,
43  	TRACE_BPRINT,
44  	TRACE_MMIO_RW,
45  	TRACE_MMIO_MAP,
46  	TRACE_BRANCH,
47  	TRACE_GRAPH_RET,
48  	TRACE_GRAPH_ENT,
49  	TRACE_USER_STACK,
50  	TRACE_BLK,
51  	TRACE_BPUTS,
52  	TRACE_HWLAT,
53  	TRACE_OSNOISE,
54  	TRACE_TIMERLAT,
55  	TRACE_RAW_DATA,
56  	TRACE_FUNC_REPEATS,
57  
58  	__TRACE_LAST_TYPE,
59  };
60  
61  
62  #undef __field
63  #define __field(type, item)		type	item;
64  
65  #undef __field_fn
66  #define __field_fn(type, item)		type	item;
67  
68  #undef __field_struct
69  #define __field_struct(type, item)	__field(type, item)
70  
71  #undef __field_desc
72  #define __field_desc(type, container, item)
73  
74  #undef __field_packed
75  #define __field_packed(type, container, item)
76  
77  #undef __array
78  #define __array(type, item, size)	type	item[size];
79  
80  /*
81   * For backward compatibility, older user space expects to see the
82   * kernel_stack event with a fixed size caller field. But today the fix
83   * size is ignored by the kernel, and the real structure is dynamic.
84   * Expose to user space: "unsigned long caller[8];" but the real structure
85   * will be "unsigned long caller[] __counted_by(size)"
86   */
87  #undef __stack_array
88  #define __stack_array(type, item, size, field)		type item[] __counted_by(field);
89  
90  #undef __array_desc
91  #define __array_desc(type, container, item, size)
92  
93  #undef __dynamic_array
94  #define __dynamic_array(type, item)	type	item[];
95  
96  #undef __rel_dynamic_array
97  #define __rel_dynamic_array(type, item)	type	item[];
98  
99  #undef F_STRUCT
100  #define F_STRUCT(args...)		args
101  
102  #undef FTRACE_ENTRY
103  #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
104  	struct struct_name {						\
105  		struct trace_entry	ent;				\
106  		tstruct							\
107  	}
108  
109  #undef FTRACE_ENTRY_DUP
110  #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
111  
112  #undef FTRACE_ENTRY_REG
113  #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
114  	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
115  
116  #undef FTRACE_ENTRY_PACKED
117  #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
118  	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
119  
120  #include "trace_entries.h"
121  
122  /* Use this for memory failure errors */
123  #define MEM_FAIL(condition, fmt, ...)					\
124  	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
125  
126  #define FAULT_STRING "(fault)"
127  
128  #define HIST_STACKTRACE_DEPTH	16
129  #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
130  #define HIST_STACKTRACE_SKIP	5
131  
132  /*
133   * syscalls are special, and need special handling, this is why
134   * they are not included in trace_entries.h
135   */
136  struct syscall_trace_enter {
137  	struct trace_entry	ent;
138  	int			nr;
139  	unsigned long		args[];
140  };
141  
142  struct syscall_trace_exit {
143  	struct trace_entry	ent;
144  	int			nr;
145  	long			ret;
146  };
147  
148  struct kprobe_trace_entry_head {
149  	struct trace_entry	ent;
150  	unsigned long		ip;
151  };
152  
153  struct eprobe_trace_entry_head {
154  	struct trace_entry	ent;
155  };
156  
157  struct kretprobe_trace_entry_head {
158  	struct trace_entry	ent;
159  	unsigned long		func;
160  	unsigned long		ret_ip;
161  };
162  
163  struct fentry_trace_entry_head {
164  	struct trace_entry	ent;
165  	unsigned long		ip;
166  };
167  
168  struct fexit_trace_entry_head {
169  	struct trace_entry	ent;
170  	unsigned long		func;
171  	unsigned long		ret_ip;
172  };
173  
174  #define TRACE_BUF_SIZE		1024
175  
176  struct trace_array;
177  
178  /*
179   * The CPU trace array - it consists of thousands of trace entries
180   * plus some other descriptor data: (for example which task started
181   * the trace, etc.)
182   */
183  struct trace_array_cpu {
184  	atomic_t		disabled;
185  	void			*buffer_page;	/* ring buffer spare */
186  
187  	unsigned long		entries;
188  	unsigned long		saved_latency;
189  	unsigned long		critical_start;
190  	unsigned long		critical_end;
191  	unsigned long		critical_sequence;
192  	unsigned long		nice;
193  	unsigned long		policy;
194  	unsigned long		rt_priority;
195  	unsigned long		skipped_entries;
196  	u64			preempt_timestamp;
197  	pid_t			pid;
198  	kuid_t			uid;
199  	char			comm[TASK_COMM_LEN];
200  
201  #ifdef CONFIG_FUNCTION_TRACER
202  	int			ftrace_ignore_pid;
203  #endif
204  	bool			ignore_pid;
205  };
206  
207  struct tracer;
208  struct trace_option_dentry;
209  
210  struct array_buffer {
211  	struct trace_array		*tr;
212  	struct trace_buffer		*buffer;
213  	struct trace_array_cpu __percpu	*data;
214  	u64				time_start;
215  	int				cpu;
216  };
217  
218  #define TRACE_FLAGS_MAX_SIZE		32
219  
220  struct trace_options {
221  	struct tracer			*tracer;
222  	struct trace_option_dentry	*topts;
223  };
224  
225  struct trace_pid_list *trace_pid_list_alloc(void);
226  void trace_pid_list_free(struct trace_pid_list *pid_list);
227  bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
228  int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
229  int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
230  int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
231  int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
232  			unsigned int *next);
233  
234  enum {
235  	TRACE_PIDS		= BIT(0),
236  	TRACE_NO_PIDS		= BIT(1),
237  };
238  
pid_type_enabled(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)239  static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
240  				    struct trace_pid_list *no_pid_list)
241  {
242  	/* Return true if the pid list in type has pids */
243  	return ((type & TRACE_PIDS) && pid_list) ||
244  		((type & TRACE_NO_PIDS) && no_pid_list);
245  }
246  
still_need_pid_events(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)247  static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
248  					 struct trace_pid_list *no_pid_list)
249  {
250  	/*
251  	 * Turning off what is in @type, return true if the "other"
252  	 * pid list, still has pids in it.
253  	 */
254  	return (!(type & TRACE_PIDS) && pid_list) ||
255  		(!(type & TRACE_NO_PIDS) && no_pid_list);
256  }
257  
258  typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
259  
260  /**
261   * struct cond_snapshot - conditional snapshot data and callback
262   *
263   * The cond_snapshot structure encapsulates a callback function and
264   * data associated with the snapshot for a given tracing instance.
265   *
266   * When a snapshot is taken conditionally, by invoking
267   * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
268   * passed in turn to the cond_snapshot.update() function.  That data
269   * can be compared by the update() implementation with the cond_data
270   * contained within the struct cond_snapshot instance associated with
271   * the trace_array.  Because the tr->max_lock is held throughout the
272   * update() call, the update() function can directly retrieve the
273   * cond_snapshot and cond_data associated with the per-instance
274   * snapshot associated with the trace_array.
275   *
276   * The cond_snapshot.update() implementation can save data to be
277   * associated with the snapshot if it decides to, and returns 'true'
278   * in that case, or it returns 'false' if the conditional snapshot
279   * shouldn't be taken.
280   *
281   * The cond_snapshot instance is created and associated with the
282   * user-defined cond_data by tracing_cond_snapshot_enable().
283   * Likewise, the cond_snapshot instance is destroyed and is no longer
284   * associated with the trace instance by
285   * tracing_cond_snapshot_disable().
286   *
287   * The method below is required.
288   *
289   * @update: When a conditional snapshot is invoked, the update()
290   *	callback function is invoked with the tr->max_lock held.  The
291   *	update() implementation signals whether or not to actually
292   *	take the snapshot, by returning 'true' if so, 'false' if no
293   *	snapshot should be taken.  Because the max_lock is held for
294   *	the duration of update(), the implementation is safe to
295   *	directly retrieved and save any implementation data it needs
296   *	to in association with the snapshot.
297   */
298  struct cond_snapshot {
299  	void				*cond_data;
300  	cond_update_fn_t		update;
301  };
302  
303  /*
304   * struct trace_func_repeats - used to keep track of the consecutive
305   * (on the same CPU) calls of a single function.
306   */
307  struct trace_func_repeats {
308  	unsigned long	ip;
309  	unsigned long	parent_ip;
310  	unsigned long	count;
311  	u64		ts_last_call;
312  };
313  
314  /*
315   * The trace array - an array of per-CPU trace arrays. This is the
316   * highest level data structure that individual tracers deal with.
317   * They have on/off state as well:
318   */
319  struct trace_array {
320  	struct list_head	list;
321  	char			*name;
322  	struct array_buffer	array_buffer;
323  #ifdef CONFIG_TRACER_MAX_TRACE
324  	/*
325  	 * The max_buffer is used to snapshot the trace when a maximum
326  	 * latency is reached, or when the user initiates a snapshot.
327  	 * Some tracers will use this to store a maximum trace while
328  	 * it continues examining live traces.
329  	 *
330  	 * The buffers for the max_buffer are set up the same as the array_buffer
331  	 * When a snapshot is taken, the buffer of the max_buffer is swapped
332  	 * with the buffer of the array_buffer and the buffers are reset for
333  	 * the array_buffer so the tracing can continue.
334  	 */
335  	struct array_buffer	max_buffer;
336  	bool			allocated_snapshot;
337  	spinlock_t		snapshot_trigger_lock;
338  	unsigned int		snapshot;
339  	unsigned long		max_latency;
340  #ifdef CONFIG_FSNOTIFY
341  	struct dentry		*d_max_latency;
342  	struct work_struct	fsnotify_work;
343  	struct irq_work		fsnotify_irqwork;
344  #endif
345  #endif
346  	/* The below is for memory mapped ring buffer */
347  	unsigned int		mapped;
348  	unsigned long		range_addr_start;
349  	unsigned long		range_addr_size;
350  	long			text_delta;
351  	long			data_delta;
352  
353  	struct trace_pid_list	__rcu *filtered_pids;
354  	struct trace_pid_list	__rcu *filtered_no_pids;
355  	/*
356  	 * max_lock is used to protect the swapping of buffers
357  	 * when taking a max snapshot. The buffers themselves are
358  	 * protected by per_cpu spinlocks. But the action of the swap
359  	 * needs its own lock.
360  	 *
361  	 * This is defined as a arch_spinlock_t in order to help
362  	 * with performance when lockdep debugging is enabled.
363  	 *
364  	 * It is also used in other places outside the update_max_tr
365  	 * so it needs to be defined outside of the
366  	 * CONFIG_TRACER_MAX_TRACE.
367  	 */
368  	arch_spinlock_t		max_lock;
369  	int			buffer_disabled;
370  #ifdef CONFIG_FTRACE_SYSCALLS
371  	int			sys_refcount_enter;
372  	int			sys_refcount_exit;
373  	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
374  	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
375  #endif
376  	int			stop_count;
377  	int			clock_id;
378  	int			nr_topts;
379  	bool			clear_trace;
380  	int			buffer_percent;
381  	unsigned int		n_err_log_entries;
382  	struct tracer		*current_trace;
383  	unsigned int		trace_flags;
384  	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
385  	unsigned int		flags;
386  	raw_spinlock_t		start_lock;
387  	const char		*system_names;
388  	struct list_head	err_log;
389  	struct dentry		*dir;
390  	struct dentry		*options;
391  	struct dentry		*percpu_dir;
392  	struct eventfs_inode	*event_dir;
393  	struct trace_options	*topts;
394  	struct list_head	systems;
395  	struct list_head	events;
396  	struct trace_event_file *trace_marker_file;
397  	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
398  	/* one per_cpu trace_pipe can be opened by only one user */
399  	cpumask_var_t		pipe_cpumask;
400  	int			ref;
401  	int			trace_ref;
402  #ifdef CONFIG_FUNCTION_TRACER
403  	struct ftrace_ops	*ops;
404  	struct trace_pid_list	__rcu *function_pids;
405  	struct trace_pid_list	__rcu *function_no_pids;
406  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
407  	struct fgraph_ops	*gops;
408  #endif
409  #ifdef CONFIG_DYNAMIC_FTRACE
410  	/* All of these are protected by the ftrace_lock */
411  	struct list_head	func_probes;
412  	struct list_head	mod_trace;
413  	struct list_head	mod_notrace;
414  #endif
415  	/* function tracing enabled */
416  	int			function_enabled;
417  #endif
418  	int			no_filter_buffering_ref;
419  	struct list_head	hist_vars;
420  #ifdef CONFIG_TRACER_SNAPSHOT
421  	struct cond_snapshot	*cond_snapshot;
422  #endif
423  	struct trace_func_repeats	__percpu *last_func_repeats;
424  	/*
425  	 * On boot up, the ring buffer is set to the minimum size, so that
426  	 * we do not waste memory on systems that are not using tracing.
427  	 */
428  	bool ring_buffer_expanded;
429  };
430  
431  enum {
432  	TRACE_ARRAY_FL_GLOBAL	= BIT(0),
433  	TRACE_ARRAY_FL_BOOT	= BIT(1),
434  };
435  
436  extern struct list_head ftrace_trace_arrays;
437  
438  extern struct mutex trace_types_lock;
439  
440  extern int trace_array_get(struct trace_array *tr);
441  extern int tracing_check_open_get_tr(struct trace_array *tr);
442  extern struct trace_array *trace_array_find(const char *instance);
443  extern struct trace_array *trace_array_find_get(const char *instance);
444  
445  extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
446  extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
447  extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
448  
449  extern bool trace_clock_in_ns(struct trace_array *tr);
450  
451  /*
452   * The global tracer (top) should be the first trace array added,
453   * but we check the flag anyway.
454   */
top_trace_array(void)455  static inline struct trace_array *top_trace_array(void)
456  {
457  	struct trace_array *tr;
458  
459  	if (list_empty(&ftrace_trace_arrays))
460  		return NULL;
461  
462  	tr = list_entry(ftrace_trace_arrays.prev,
463  			typeof(*tr), list);
464  	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
465  	return tr;
466  }
467  
468  #define FTRACE_CMP_TYPE(var, type) \
469  	__builtin_types_compatible_p(typeof(var), type *)
470  
471  #undef IF_ASSIGN
472  #define IF_ASSIGN(var, entry, etype, id)			\
473  	if (FTRACE_CMP_TYPE(var, etype)) {			\
474  		var = (typeof(var))(entry);			\
475  		WARN_ON(id != 0 && (entry)->type != id);	\
476  		break;						\
477  	}
478  
479  /* Will cause compile errors if type is not found. */
480  extern void __ftrace_bad_type(void);
481  
482  /*
483   * The trace_assign_type is a verifier that the entry type is
484   * the same as the type being assigned. To add new types simply
485   * add a line with the following format:
486   *
487   * IF_ASSIGN(var, ent, type, id);
488   *
489   *  Where "type" is the trace type that includes the trace_entry
490   *  as the "ent" item. And "id" is the trace identifier that is
491   *  used in the trace_type enum.
492   *
493   *  If the type can have more than one id, then use zero.
494   */
495  #define trace_assign_type(var, ent)					\
496  	do {								\
497  		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
498  		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
499  		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
500  		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
501  		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
502  		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
503  		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
504  		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
505  		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
506  		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
507  		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
508  		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
509  			  TRACE_MMIO_RW);				\
510  		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
511  			  TRACE_MMIO_MAP);				\
512  		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
513  		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
514  			  TRACE_GRAPH_ENT);		\
515  		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
516  			  TRACE_GRAPH_RET);		\
517  		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
518  			  TRACE_FUNC_REPEATS);				\
519  		__ftrace_bad_type();					\
520  	} while (0)
521  
522  /*
523   * An option specific to a tracer. This is a boolean value.
524   * The bit is the bit index that sets its value on the
525   * flags value in struct tracer_flags.
526   */
527  struct tracer_opt {
528  	const char	*name; /* Will appear on the trace_options file */
529  	u32		bit; /* Mask assigned in val field in tracer_flags */
530  };
531  
532  /*
533   * The set of specific options for a tracer. Your tracer
534   * have to set the initial value of the flags val.
535   */
536  struct tracer_flags {
537  	u32			val;
538  	struct tracer_opt	*opts;
539  	struct tracer		*trace;
540  };
541  
542  /* Makes more easy to define a tracer opt */
543  #define TRACER_OPT(s, b)	.name = #s, .bit = b
544  
545  
546  struct trace_option_dentry {
547  	struct tracer_opt		*opt;
548  	struct tracer_flags		*flags;
549  	struct trace_array		*tr;
550  	struct dentry			*entry;
551  };
552  
553  /**
554   * struct tracer - a specific tracer and its callbacks to interact with tracefs
555   * @name: the name chosen to select it on the available_tracers file
556   * @init: called when one switches to this tracer (echo name > current_tracer)
557   * @reset: called when one switches to another tracer
558   * @start: called when tracing is unpaused (echo 1 > tracing_on)
559   * @stop: called when tracing is paused (echo 0 > tracing_on)
560   * @update_thresh: called when tracing_thresh is updated
561   * @open: called when the trace file is opened
562   * @pipe_open: called when the trace_pipe file is opened
563   * @close: called when the trace file is released
564   * @pipe_close: called when the trace_pipe file is released
565   * @read: override the default read callback on trace_pipe
566   * @splice_read: override the default splice_read callback on trace_pipe
567   * @selftest: selftest to run on boot (see trace_selftest.c)
568   * @print_headers: override the first lines that describe your columns
569   * @print_line: callback that prints a trace
570   * @set_flag: signals one of your private flags changed (trace_options file)
571   * @flags: your private flags
572   */
573  struct tracer {
574  	const char		*name;
575  	int			(*init)(struct trace_array *tr);
576  	void			(*reset)(struct trace_array *tr);
577  	void			(*start)(struct trace_array *tr);
578  	void			(*stop)(struct trace_array *tr);
579  	int			(*update_thresh)(struct trace_array *tr);
580  	void			(*open)(struct trace_iterator *iter);
581  	void			(*pipe_open)(struct trace_iterator *iter);
582  	void			(*close)(struct trace_iterator *iter);
583  	void			(*pipe_close)(struct trace_iterator *iter);
584  	ssize_t			(*read)(struct trace_iterator *iter,
585  					struct file *filp, char __user *ubuf,
586  					size_t cnt, loff_t *ppos);
587  	ssize_t			(*splice_read)(struct trace_iterator *iter,
588  					       struct file *filp,
589  					       loff_t *ppos,
590  					       struct pipe_inode_info *pipe,
591  					       size_t len,
592  					       unsigned int flags);
593  #ifdef CONFIG_FTRACE_STARTUP_TEST
594  	int			(*selftest)(struct tracer *trace,
595  					    struct trace_array *tr);
596  #endif
597  	void			(*print_header)(struct seq_file *m);
598  	enum print_line_t	(*print_line)(struct trace_iterator *iter);
599  	/* If you handled the flag setting, return 0 */
600  	int			(*set_flag)(struct trace_array *tr,
601  					    u32 old_flags, u32 bit, int set);
602  	/* Return 0 if OK with change, else return non-zero */
603  	int			(*flag_changed)(struct trace_array *tr,
604  						u32 mask, int set);
605  	struct tracer		*next;
606  	struct tracer_flags	*flags;
607  	int			enabled;
608  	bool			print_max;
609  	bool			allow_instances;
610  #ifdef CONFIG_TRACER_MAX_TRACE
611  	bool			use_max_tr;
612  #endif
613  	/* True if tracer cannot be enabled in kernel param */
614  	bool			noboot;
615  };
616  
617  static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator * iter,int cpu)618  trace_buffer_iter(struct trace_iterator *iter, int cpu)
619  {
620  	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
621  }
622  
623  int tracer_init(struct tracer *t, struct trace_array *tr);
624  int tracing_is_enabled(void);
625  void tracing_reset_online_cpus(struct array_buffer *buf);
626  void tracing_reset_all_online_cpus(void);
627  void tracing_reset_all_online_cpus_unlocked(void);
628  int tracing_open_generic(struct inode *inode, struct file *filp);
629  int tracing_open_generic_tr(struct inode *inode, struct file *filp);
630  int tracing_release_generic_tr(struct inode *inode, struct file *file);
631  int tracing_open_file_tr(struct inode *inode, struct file *filp);
632  int tracing_release_file_tr(struct inode *inode, struct file *filp);
633  int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
634  bool tracing_is_disabled(void);
635  bool tracer_tracing_is_on(struct trace_array *tr);
636  void tracer_tracing_on(struct trace_array *tr);
637  void tracer_tracing_off(struct trace_array *tr);
638  struct dentry *trace_create_file(const char *name,
639  				 umode_t mode,
640  				 struct dentry *parent,
641  				 void *data,
642  				 const struct file_operations *fops);
643  
644  int tracing_init_dentry(void);
645  
646  struct ring_buffer_event;
647  
648  struct ring_buffer_event *
649  trace_buffer_lock_reserve(struct trace_buffer *buffer,
650  			  int type,
651  			  unsigned long len,
652  			  unsigned int trace_ctx);
653  
654  int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
655  
656  struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
657  						struct trace_array_cpu *data);
658  
659  struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
660  					  int *ent_cpu, u64 *ent_ts);
661  
662  void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
663  					struct ring_buffer_event *event);
664  
665  bool trace_is_tracepoint_string(const char *str);
666  const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
667  void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
668  			 va_list ap) __printf(2, 0);
669  char *trace_iter_expand_format(struct trace_iterator *iter);
670  
671  int trace_empty(struct trace_iterator *iter);
672  
673  void *trace_find_next_entry_inc(struct trace_iterator *iter);
674  
675  void trace_init_global_iter(struct trace_iterator *iter);
676  
677  void tracing_iter_reset(struct trace_iterator *iter, int cpu);
678  
679  unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
680  unsigned long trace_total_entries(struct trace_array *tr);
681  
682  void trace_function(struct trace_array *tr,
683  		    unsigned long ip,
684  		    unsigned long parent_ip,
685  		    unsigned int trace_ctx);
686  void trace_graph_function(struct trace_array *tr,
687  		    unsigned long ip,
688  		    unsigned long parent_ip,
689  		    unsigned int trace_ctx);
690  void trace_latency_header(struct seq_file *m);
691  void trace_default_header(struct seq_file *m);
692  void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
693  
694  void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
695  int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
696  
697  void tracing_start_cmdline_record(void);
698  void tracing_stop_cmdline_record(void);
699  void tracing_start_tgid_record(void);
700  void tracing_stop_tgid_record(void);
701  
702  int register_tracer(struct tracer *type);
703  int is_tracing_stopped(void);
704  
705  loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
706  
707  extern cpumask_var_t __read_mostly tracing_buffer_mask;
708  
709  #define for_each_tracing_cpu(cpu)	\
710  	for_each_cpu(cpu, tracing_buffer_mask)
711  
712  extern unsigned long nsecs_to_usecs(unsigned long nsecs);
713  
714  extern unsigned long tracing_thresh;
715  
716  /* PID filtering */
717  
718  extern int pid_max;
719  
720  bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
721  			     pid_t search_pid);
722  bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
723  			    struct trace_pid_list *filtered_no_pids,
724  			    struct task_struct *task);
725  void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
726  				  struct task_struct *self,
727  				  struct task_struct *task);
728  void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
729  void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
730  int trace_pid_show(struct seq_file *m, void *v);
731  int trace_pid_write(struct trace_pid_list *filtered_pids,
732  		    struct trace_pid_list **new_pid_list,
733  		    const char __user *ubuf, size_t cnt);
734  
735  #ifdef CONFIG_TRACER_MAX_TRACE
736  void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
737  		   void *cond_data);
738  void update_max_tr_single(struct trace_array *tr,
739  			  struct task_struct *tsk, int cpu);
740  
741  #ifdef CONFIG_FSNOTIFY
742  #define LATENCY_FS_NOTIFY
743  #endif
744  #endif /* CONFIG_TRACER_MAX_TRACE */
745  
746  #ifdef LATENCY_FS_NOTIFY
747  void latency_fsnotify(struct trace_array *tr);
748  #else
latency_fsnotify(struct trace_array * tr)749  static inline void latency_fsnotify(struct trace_array *tr) { }
750  #endif
751  
752  #ifdef CONFIG_STACKTRACE
753  void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
754  #else
__trace_stack(struct trace_array * tr,unsigned int trace_ctx,int skip)755  static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
756  				 int skip)
757  {
758  }
759  #endif /* CONFIG_STACKTRACE */
760  
761  void trace_last_func_repeats(struct trace_array *tr,
762  			     struct trace_func_repeats *last_info,
763  			     unsigned int trace_ctx);
764  
765  extern u64 ftrace_now(int cpu);
766  
767  extern void trace_find_cmdline(int pid, char comm[]);
768  extern int trace_find_tgid(int pid);
769  extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
770  
771  #ifdef CONFIG_DYNAMIC_FTRACE
772  extern unsigned long ftrace_update_tot_cnt;
773  extern unsigned long ftrace_number_of_pages;
774  extern unsigned long ftrace_number_of_groups;
775  void ftrace_init_trace_array(struct trace_array *tr);
776  #else
ftrace_init_trace_array(struct trace_array * tr)777  static inline void ftrace_init_trace_array(struct trace_array *tr) { }
778  #endif
779  #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
780  extern int DYN_FTRACE_TEST_NAME(void);
781  #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
782  extern int DYN_FTRACE_TEST_NAME2(void);
783  
784  extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
785  extern bool tracing_selftest_disabled;
786  
787  #ifdef CONFIG_FTRACE_STARTUP_TEST
788  extern void __init disable_tracing_selftest(const char *reason);
789  
790  extern int trace_selftest_startup_function(struct tracer *trace,
791  					   struct trace_array *tr);
792  extern int trace_selftest_startup_function_graph(struct tracer *trace,
793  						 struct trace_array *tr);
794  extern int trace_selftest_startup_irqsoff(struct tracer *trace,
795  					  struct trace_array *tr);
796  extern int trace_selftest_startup_preemptoff(struct tracer *trace,
797  					     struct trace_array *tr);
798  extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
799  						 struct trace_array *tr);
800  extern int trace_selftest_startup_wakeup(struct tracer *trace,
801  					 struct trace_array *tr);
802  extern int trace_selftest_startup_nop(struct tracer *trace,
803  					 struct trace_array *tr);
804  extern int trace_selftest_startup_branch(struct tracer *trace,
805  					 struct trace_array *tr);
806  /*
807   * Tracer data references selftest functions that only occur
808   * on boot up. These can be __init functions. Thus, when selftests
809   * are enabled, then the tracers need to reference __init functions.
810   */
811  #define __tracer_data		__refdata
812  #else
disable_tracing_selftest(const char * reason)813  static inline void __init disable_tracing_selftest(const char *reason)
814  {
815  }
816  /* Tracers are seldom changed. Optimize when selftests are disabled. */
817  #define __tracer_data		__read_mostly
818  #endif /* CONFIG_FTRACE_STARTUP_TEST */
819  
820  extern void *head_page(struct trace_array_cpu *data);
821  extern unsigned long long ns2usecs(u64 nsec);
822  extern int
823  trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
824  extern int
825  trace_vprintk(unsigned long ip, const char *fmt, va_list args);
826  extern int
827  trace_array_vprintk(struct trace_array *tr,
828  		    unsigned long ip, const char *fmt, va_list args);
829  int trace_array_printk_buf(struct trace_buffer *buffer,
830  			   unsigned long ip, const char *fmt, ...);
831  void trace_printk_seq(struct trace_seq *s);
832  enum print_line_t print_trace_line(struct trace_iterator *iter);
833  
834  extern char trace_find_mark(unsigned long long duration);
835  
836  struct ftrace_hash;
837  
838  struct ftrace_mod_load {
839  	struct list_head	list;
840  	char			*func;
841  	char			*module;
842  	int			 enable;
843  };
844  
845  enum {
846  	FTRACE_HASH_FL_MOD	= (1 << 0),
847  };
848  
849  struct ftrace_hash {
850  	unsigned long		size_bits;
851  	struct hlist_head	*buckets;
852  	unsigned long		count;
853  	unsigned long		flags;
854  	struct rcu_head		rcu;
855  };
856  
857  struct ftrace_func_entry *
858  ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
859  
ftrace_hash_empty(struct ftrace_hash * hash)860  static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
861  {
862  	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
863  }
864  
865  /* Standard output formatting function used for function return traces */
866  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
867  
868  /* Flag options */
869  #define TRACE_GRAPH_PRINT_OVERRUN       0x1
870  #define TRACE_GRAPH_PRINT_CPU           0x2
871  #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
872  #define TRACE_GRAPH_PRINT_PROC          0x8
873  #define TRACE_GRAPH_PRINT_DURATION      0x10
874  #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
875  #define TRACE_GRAPH_PRINT_REL_TIME      0x40
876  #define TRACE_GRAPH_PRINT_IRQS          0x80
877  #define TRACE_GRAPH_PRINT_TAIL          0x100
878  #define TRACE_GRAPH_SLEEP_TIME          0x200
879  #define TRACE_GRAPH_GRAPH_TIME          0x400
880  #define TRACE_GRAPH_PRINT_RETVAL        0x800
881  #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
882  #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
883  #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
884  
885  extern void ftrace_graph_sleep_time_control(bool enable);
886  
887  #ifdef CONFIG_FUNCTION_PROFILER
888  extern void ftrace_graph_graph_time_control(bool enable);
889  #else
ftrace_graph_graph_time_control(bool enable)890  static inline void ftrace_graph_graph_time_control(bool enable) { }
891  #endif
892  
893  extern enum print_line_t
894  print_graph_function_flags(struct trace_iterator *iter, u32 flags);
895  extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
896  extern void
897  trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
898  extern void graph_trace_open(struct trace_iterator *iter);
899  extern void graph_trace_close(struct trace_iterator *iter);
900  extern int __trace_graph_entry(struct trace_array *tr,
901  			       struct ftrace_graph_ent *trace,
902  			       unsigned int trace_ctx);
903  extern void __trace_graph_return(struct trace_array *tr,
904  				 struct ftrace_graph_ret *trace,
905  				 unsigned int trace_ctx);
906  extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
907  extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
908  extern void free_fgraph_ops(struct trace_array *tr);
909  
910  enum {
911  	TRACE_GRAPH_FL		= 1,
912  
913  	/*
914  	 * In the very unlikely case that an interrupt came in
915  	 * at a start of graph tracing, and we want to trace
916  	 * the function in that interrupt, the depth can be greater
917  	 * than zero, because of the preempted start of a previous
918  	 * trace. In an even more unlikely case, depth could be 2
919  	 * if a softirq interrupted the start of graph tracing,
920  	 * followed by an interrupt preempting a start of graph
921  	 * tracing in the softirq, and depth can even be 3
922  	 * if an NMI came in at the start of an interrupt function
923  	 * that preempted a softirq start of a function that
924  	 * preempted normal context!!!! Luckily, it can't be
925  	 * greater than 3, so the next two bits are a mask
926  	 * of what the depth is when we set TRACE_GRAPH_FL
927  	 */
928  
929  	TRACE_GRAPH_DEPTH_START_BIT,
930  	TRACE_GRAPH_DEPTH_END_BIT,
931  
932  	/*
933  	 * To implement set_graph_notrace, if this bit is set, we ignore
934  	 * function graph tracing of called functions, until the return
935  	 * function is called to clear it.
936  	 */
937  	TRACE_GRAPH_NOTRACE_BIT,
938  };
939  
940  #define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
941  
ftrace_graph_depth(unsigned long * task_var)942  static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
943  {
944  	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
945  }
946  
ftrace_graph_set_depth(unsigned long * task_var,int depth)947  static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
948  {
949  	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
950  	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
951  }
952  
953  #ifdef CONFIG_DYNAMIC_FTRACE
954  extern struct ftrace_hash __rcu *ftrace_graph_hash;
955  extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
956  
957  static inline int
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)958  ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
959  {
960  	unsigned long addr = trace->func;
961  	int ret = 0;
962  	struct ftrace_hash *hash;
963  
964  	preempt_disable_notrace();
965  
966  	/*
967  	 * Have to open code "rcu_dereference_sched()" because the
968  	 * function graph tracer can be called when RCU is not
969  	 * "watching".
970  	 * Protected with schedule_on_each_cpu(ftrace_sync)
971  	 */
972  	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
973  
974  	if (ftrace_hash_empty(hash)) {
975  		ret = 1;
976  		goto out;
977  	}
978  
979  	if (ftrace_lookup_ip(hash, addr)) {
980  		/*
981  		 * This needs to be cleared on the return functions
982  		 * when the depth is zero.
983  		 */
984  		*task_var |= TRACE_GRAPH_FL;
985  		ftrace_graph_set_depth(task_var, trace->depth);
986  
987  		/*
988  		 * If no irqs are to be traced, but a set_graph_function
989  		 * is set, and called by an interrupt handler, we still
990  		 * want to trace it.
991  		 */
992  		if (in_hardirq())
993  			trace_recursion_set(TRACE_IRQ_BIT);
994  		else
995  			trace_recursion_clear(TRACE_IRQ_BIT);
996  		ret = 1;
997  	}
998  
999  out:
1000  	preempt_enable_notrace();
1001  	return ret;
1002  }
1003  
1004  static inline void
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1005  ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1006  {
1007  	unsigned long *task_var = fgraph_get_task_var(gops);
1008  
1009  	if ((*task_var & TRACE_GRAPH_FL) &&
1010  	    trace->depth == ftrace_graph_depth(task_var))
1011  		*task_var &= ~TRACE_GRAPH_FL;
1012  }
1013  
ftrace_graph_notrace_addr(unsigned long addr)1014  static inline int ftrace_graph_notrace_addr(unsigned long addr)
1015  {
1016  	int ret = 0;
1017  	struct ftrace_hash *notrace_hash;
1018  
1019  	preempt_disable_notrace();
1020  
1021  	/*
1022  	 * Have to open code "rcu_dereference_sched()" because the
1023  	 * function graph tracer can be called when RCU is not
1024  	 * "watching".
1025  	 * Protected with schedule_on_each_cpu(ftrace_sync)
1026  	 */
1027  	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1028  						 !preemptible());
1029  
1030  	if (ftrace_lookup_ip(notrace_hash, addr))
1031  		ret = 1;
1032  
1033  	preempt_enable_notrace();
1034  	return ret;
1035  }
1036  #else
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)1037  static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1038  {
1039  	return 1;
1040  }
1041  
ftrace_graph_notrace_addr(unsigned long addr)1042  static inline int ftrace_graph_notrace_addr(unsigned long addr)
1043  {
1044  	return 0;
1045  }
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1046  static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1047  { }
1048  #endif /* CONFIG_DYNAMIC_FTRACE */
1049  
1050  extern unsigned int fgraph_max_depth;
1051  
1052  static inline bool
ftrace_graph_ignore_func(struct fgraph_ops * gops,struct ftrace_graph_ent * trace)1053  ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1054  {
1055  	unsigned long *task_var = fgraph_get_task_var(gops);
1056  
1057  	/* trace it when it is-nested-in or is a function enabled. */
1058  	return !((*task_var & TRACE_GRAPH_FL) ||
1059  		 ftrace_graph_addr(task_var, trace)) ||
1060  		(trace->depth < 0) ||
1061  		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1062  }
1063  
1064  void fgraph_init_ops(struct ftrace_ops *dst_ops,
1065  		     struct ftrace_ops *src_ops);
1066  
1067  #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1068  static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)1069  print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1070  {
1071  	return TRACE_TYPE_UNHANDLED;
1072  }
free_fgraph_ops(struct trace_array * tr)1073  static inline void free_fgraph_ops(struct trace_array *tr) { }
1074  /* ftrace_ops may not be defined */
1075  #define init_array_fgraph_ops(tr, ops) do { } while (0)
1076  #define allocate_fgraph_ops(tr, ops) ({ 0; })
1077  #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1078  
1079  extern struct list_head ftrace_pids;
1080  
1081  #ifdef CONFIG_FUNCTION_TRACER
1082  
1083  #define FTRACE_PID_IGNORE	-1
1084  #define FTRACE_PID_TRACE	-2
1085  
1086  struct ftrace_func_command {
1087  	struct list_head	list;
1088  	char			*name;
1089  	int			(*func)(struct trace_array *tr,
1090  					struct ftrace_hash *hash,
1091  					char *func, char *cmd,
1092  					char *params, int enable);
1093  };
1094  extern bool ftrace_filter_param __initdata;
ftrace_trace_task(struct trace_array * tr)1095  static inline int ftrace_trace_task(struct trace_array *tr)
1096  {
1097  	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1098  		FTRACE_PID_IGNORE;
1099  }
1100  extern int ftrace_is_dead(void);
1101  int ftrace_create_function_files(struct trace_array *tr,
1102  				 struct dentry *parent);
1103  void ftrace_destroy_function_files(struct trace_array *tr);
1104  int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1105  void ftrace_free_ftrace_ops(struct trace_array *tr);
1106  void ftrace_init_global_array_ops(struct trace_array *tr);
1107  void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1108  void ftrace_reset_array_ops(struct trace_array *tr);
1109  void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1110  void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1111  				  struct dentry *d_tracer);
1112  void ftrace_clear_pids(struct trace_array *tr);
1113  int init_function_trace(void);
1114  void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1115  #else
ftrace_trace_task(struct trace_array * tr)1116  static inline int ftrace_trace_task(struct trace_array *tr)
1117  {
1118  	return 1;
1119  }
ftrace_is_dead(void)1120  static inline int ftrace_is_dead(void) { return 0; }
1121  static inline int
ftrace_create_function_files(struct trace_array * tr,struct dentry * parent)1122  ftrace_create_function_files(struct trace_array *tr,
1123  			     struct dentry *parent)
1124  {
1125  	return 0;
1126  }
ftrace_allocate_ftrace_ops(struct trace_array * tr)1127  static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1128  {
1129  	return 0;
1130  }
ftrace_free_ftrace_ops(struct trace_array * tr)1131  static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
ftrace_destroy_function_files(struct trace_array * tr)1132  static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1133  static inline __init void
ftrace_init_global_array_ops(struct trace_array * tr)1134  ftrace_init_global_array_ops(struct trace_array *tr) { }
ftrace_reset_array_ops(struct trace_array * tr)1135  static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
ftrace_init_tracefs(struct trace_array * tr,struct dentry * d)1136  static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
ftrace_init_tracefs_toplevel(struct trace_array * tr,struct dentry * d)1137  static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
ftrace_clear_pids(struct trace_array * tr)1138  static inline void ftrace_clear_pids(struct trace_array *tr) { }
init_function_trace(void)1139  static inline int init_function_trace(void) { return 0; }
ftrace_pid_follow_fork(struct trace_array * tr,bool enable)1140  static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1141  /* ftace_func_t type is not defined, use macro instead of static inline */
1142  #define ftrace_init_array_ops(tr, func) do { } while (0)
1143  #endif /* CONFIG_FUNCTION_TRACER */
1144  
1145  #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1146  
1147  struct ftrace_probe_ops {
1148  	void			(*func)(unsigned long ip,
1149  					unsigned long parent_ip,
1150  					struct trace_array *tr,
1151  					struct ftrace_probe_ops *ops,
1152  					void *data);
1153  	int			(*init)(struct ftrace_probe_ops *ops,
1154  					struct trace_array *tr,
1155  					unsigned long ip, void *init_data,
1156  					void **data);
1157  	void			(*free)(struct ftrace_probe_ops *ops,
1158  					struct trace_array *tr,
1159  					unsigned long ip, void *data);
1160  	int			(*print)(struct seq_file *m,
1161  					 unsigned long ip,
1162  					 struct ftrace_probe_ops *ops,
1163  					 void *data);
1164  };
1165  
1166  struct ftrace_func_mapper;
1167  typedef int (*ftrace_mapper_func)(void *data);
1168  
1169  struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1170  void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1171  					   unsigned long ip);
1172  int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1173  			       unsigned long ip, void *data);
1174  void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1175  				   unsigned long ip);
1176  void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1177  			     ftrace_mapper_func free_func);
1178  
1179  extern int
1180  register_ftrace_function_probe(char *glob, struct trace_array *tr,
1181  			       struct ftrace_probe_ops *ops, void *data);
1182  extern int
1183  unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1184  				      struct ftrace_probe_ops *ops);
1185  extern void clear_ftrace_function_probes(struct trace_array *tr);
1186  
1187  int register_ftrace_command(struct ftrace_func_command *cmd);
1188  int unregister_ftrace_command(struct ftrace_func_command *cmd);
1189  
1190  void ftrace_create_filter_files(struct ftrace_ops *ops,
1191  				struct dentry *parent);
1192  void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1193  
1194  extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1195  			     int len, int reset);
1196  extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1197  			      int len, int reset);
1198  #else
1199  struct ftrace_func_command;
1200  
register_ftrace_command(struct ftrace_func_command * cmd)1201  static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1202  {
1203  	return -EINVAL;
1204  }
unregister_ftrace_command(char * cmd_name)1205  static inline __init int unregister_ftrace_command(char *cmd_name)
1206  {
1207  	return -EINVAL;
1208  }
clear_ftrace_function_probes(struct trace_array * tr)1209  static inline void clear_ftrace_function_probes(struct trace_array *tr)
1210  {
1211  }
1212  
1213  /*
1214   * The ops parameter passed in is usually undefined.
1215   * This must be a macro.
1216   */
1217  #define ftrace_create_filter_files(ops, parent) do { } while (0)
1218  #define ftrace_destroy_filter_files(ops) do { } while (0)
1219  #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1220  
1221  bool ftrace_event_is_function(struct trace_event_call *call);
1222  
1223  /*
1224   * struct trace_parser - servers for reading the user input separated by spaces
1225   * @cont: set if the input is not complete - no final space char was found
1226   * @buffer: holds the parsed user input
1227   * @idx: user input length
1228   * @size: buffer size
1229   */
1230  struct trace_parser {
1231  	bool		cont;
1232  	char		*buffer;
1233  	unsigned	idx;
1234  	unsigned	size;
1235  };
1236  
trace_parser_loaded(struct trace_parser * parser)1237  static inline bool trace_parser_loaded(struct trace_parser *parser)
1238  {
1239  	return (parser->idx != 0);
1240  }
1241  
trace_parser_cont(struct trace_parser * parser)1242  static inline bool trace_parser_cont(struct trace_parser *parser)
1243  {
1244  	return parser->cont;
1245  }
1246  
trace_parser_clear(struct trace_parser * parser)1247  static inline void trace_parser_clear(struct trace_parser *parser)
1248  {
1249  	parser->cont = false;
1250  	parser->idx = 0;
1251  }
1252  
1253  extern int trace_parser_get_init(struct trace_parser *parser, int size);
1254  extern void trace_parser_put(struct trace_parser *parser);
1255  extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1256  	size_t cnt, loff_t *ppos);
1257  
1258  /*
1259   * Only create function graph options if function graph is configured.
1260   */
1261  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1262  # define FGRAPH_FLAGS						\
1263  		C(DISPLAY_GRAPH,	"display-graph"),
1264  #else
1265  # define FGRAPH_FLAGS
1266  #endif
1267  
1268  #ifdef CONFIG_BRANCH_TRACER
1269  # define BRANCH_FLAGS					\
1270  		C(BRANCH,		"branch"),
1271  #else
1272  # define BRANCH_FLAGS
1273  #endif
1274  
1275  #ifdef CONFIG_FUNCTION_TRACER
1276  # define FUNCTION_FLAGS						\
1277  		C(FUNCTION,		"function-trace"),	\
1278  		C(FUNC_FORK,		"function-fork"),
1279  # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1280  #else
1281  # define FUNCTION_FLAGS
1282  # define FUNCTION_DEFAULT_FLAGS		0UL
1283  # define TRACE_ITER_FUNC_FORK		0UL
1284  #endif
1285  
1286  #ifdef CONFIG_STACKTRACE
1287  # define STACK_FLAGS				\
1288  		C(STACKTRACE,		"stacktrace"),
1289  #else
1290  # define STACK_FLAGS
1291  #endif
1292  
1293  /*
1294   * trace_iterator_flags is an enumeration that defines bit
1295   * positions into trace_flags that controls the output.
1296   *
1297   * NOTE: These bits must match the trace_options array in
1298   *       trace.c (this macro guarantees it).
1299   */
1300  #define TRACE_FLAGS						\
1301  		C(PRINT_PARENT,		"print-parent"),	\
1302  		C(SYM_OFFSET,		"sym-offset"),		\
1303  		C(SYM_ADDR,		"sym-addr"),		\
1304  		C(VERBOSE,		"verbose"),		\
1305  		C(RAW,			"raw"),			\
1306  		C(HEX,			"hex"),			\
1307  		C(BIN,			"bin"),			\
1308  		C(BLOCK,		"block"),		\
1309  		C(FIELDS,		"fields"),		\
1310  		C(PRINTK,		"trace_printk"),	\
1311  		C(ANNOTATE,		"annotate"),		\
1312  		C(USERSTACKTRACE,	"userstacktrace"),	\
1313  		C(SYM_USEROBJ,		"sym-userobj"),		\
1314  		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1315  		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1316  		C(LATENCY_FMT,		"latency-format"),	\
1317  		C(RECORD_CMD,		"record-cmd"),		\
1318  		C(RECORD_TGID,		"record-tgid"),		\
1319  		C(OVERWRITE,		"overwrite"),		\
1320  		C(STOP_ON_FREE,		"disable_on_free"),	\
1321  		C(IRQ_INFO,		"irq-info"),		\
1322  		C(MARKERS,		"markers"),		\
1323  		C(EVENT_FORK,		"event-fork"),		\
1324  		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1325  		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1326  		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1327  		FUNCTION_FLAGS					\
1328  		FGRAPH_FLAGS					\
1329  		STACK_FLAGS					\
1330  		BRANCH_FLAGS
1331  
1332  /*
1333   * By defining C, we can make TRACE_FLAGS a list of bit names
1334   * that will define the bits for the flag masks.
1335   */
1336  #undef C
1337  #define C(a, b) TRACE_ITER_##a##_BIT
1338  
1339  enum trace_iterator_bits {
1340  	TRACE_FLAGS
1341  	/* Make sure we don't go more than we have bits for */
1342  	TRACE_ITER_LAST_BIT
1343  };
1344  
1345  /*
1346   * By redefining C, we can make TRACE_FLAGS a list of masks that
1347   * use the bits as defined above.
1348   */
1349  #undef C
1350  #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1351  
1352  enum trace_iterator_flags { TRACE_FLAGS };
1353  
1354  /*
1355   * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1356   * control the output of kernel symbols.
1357   */
1358  #define TRACE_ITER_SYM_MASK \
1359  	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1360  
1361  extern struct tracer nop_trace;
1362  
1363  #ifdef CONFIG_BRANCH_TRACER
1364  extern int enable_branch_tracing(struct trace_array *tr);
1365  extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)1366  static inline int trace_branch_enable(struct trace_array *tr)
1367  {
1368  	if (tr->trace_flags & TRACE_ITER_BRANCH)
1369  		return enable_branch_tracing(tr);
1370  	return 0;
1371  }
trace_branch_disable(void)1372  static inline void trace_branch_disable(void)
1373  {
1374  	/* due to races, always disable */
1375  	disable_branch_tracing();
1376  }
1377  #else
trace_branch_enable(struct trace_array * tr)1378  static inline int trace_branch_enable(struct trace_array *tr)
1379  {
1380  	return 0;
1381  }
trace_branch_disable(void)1382  static inline void trace_branch_disable(void)
1383  {
1384  }
1385  #endif /* CONFIG_BRANCH_TRACER */
1386  
1387  /* set ring buffers to default size if not already done so */
1388  int tracing_update_buffers(struct trace_array *tr);
1389  
1390  union trace_synth_field {
1391  	u8				as_u8;
1392  	u16				as_u16;
1393  	u32				as_u32;
1394  	u64				as_u64;
1395  	struct trace_dynamic_info	as_dynamic;
1396  };
1397  
1398  struct ftrace_event_field {
1399  	struct list_head	link;
1400  	const char		*name;
1401  	const char		*type;
1402  	int			filter_type;
1403  	int			offset;
1404  	int			size;
1405  	int			is_signed;
1406  	int			len;
1407  };
1408  
1409  struct prog_entry;
1410  
1411  struct event_filter {
1412  	struct prog_entry __rcu	*prog;
1413  	char			*filter_string;
1414  };
1415  
1416  struct event_subsystem {
1417  	struct list_head	list;
1418  	const char		*name;
1419  	struct event_filter	*filter;
1420  	int			ref_count;
1421  };
1422  
1423  struct trace_subsystem_dir {
1424  	struct list_head		list;
1425  	struct event_subsystem		*subsystem;
1426  	struct trace_array		*tr;
1427  	struct eventfs_inode		*ei;
1428  	int				ref_count;
1429  	int				nr_events;
1430  };
1431  
1432  extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1433  				     struct trace_buffer *buffer,
1434  				     struct ring_buffer_event *event);
1435  
1436  void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1437  				     struct trace_buffer *buffer,
1438  				     struct ring_buffer_event *event,
1439  				     unsigned int trcace_ctx,
1440  				     struct pt_regs *regs);
1441  
trace_buffer_unlock_commit(struct trace_array * tr,struct trace_buffer * buffer,struct ring_buffer_event * event,unsigned int trace_ctx)1442  static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1443  					      struct trace_buffer *buffer,
1444  					      struct ring_buffer_event *event,
1445  					      unsigned int trace_ctx)
1446  {
1447  	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1448  }
1449  
1450  DECLARE_PER_CPU(bool, trace_taskinfo_save);
1451  int trace_save_cmdline(struct task_struct *tsk);
1452  int trace_create_savedcmd(void);
1453  int trace_alloc_tgid_map(void);
1454  void trace_free_saved_cmdlines_buffer(void);
1455  
1456  extern const struct file_operations tracing_saved_cmdlines_fops;
1457  extern const struct file_operations tracing_saved_tgids_fops;
1458  extern const struct file_operations tracing_saved_cmdlines_size_fops;
1459  
1460  DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1461  DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1462  void trace_buffered_event_disable(void);
1463  void trace_buffered_event_enable(void);
1464  
1465  void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1466  
1467  static inline void
__trace_event_discard_commit(struct trace_buffer * buffer,struct ring_buffer_event * event)1468  __trace_event_discard_commit(struct trace_buffer *buffer,
1469  			     struct ring_buffer_event *event)
1470  {
1471  	if (this_cpu_read(trace_buffered_event) == event) {
1472  		/* Simply release the temp buffer and enable preemption */
1473  		this_cpu_dec(trace_buffered_event_cnt);
1474  		preempt_enable_notrace();
1475  		return;
1476  	}
1477  	/* ring_buffer_discard_commit() enables preemption */
1478  	ring_buffer_discard_commit(buffer, event);
1479  }
1480  
1481  /*
1482   * Helper function for event_trigger_unlock_commit{_regs}().
1483   * If there are event triggers attached to this event that requires
1484   * filtering against its fields, then they will be called as the
1485   * entry already holds the field information of the current event.
1486   *
1487   * It also checks if the event should be discarded or not.
1488   * It is to be discarded if the event is soft disabled and the
1489   * event was only recorded to process triggers, or if the event
1490   * filter is active and this event did not match the filters.
1491   *
1492   * Returns true if the event is discarded, false otherwise.
1493   */
1494  static inline bool
__event_trigger_test_discard(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,enum event_trigger_type * tt)1495  __event_trigger_test_discard(struct trace_event_file *file,
1496  			     struct trace_buffer *buffer,
1497  			     struct ring_buffer_event *event,
1498  			     void *entry,
1499  			     enum event_trigger_type *tt)
1500  {
1501  	unsigned long eflags = file->flags;
1502  
1503  	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1504  		*tt = event_triggers_call(file, buffer, entry, event);
1505  
1506  	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1507  				    EVENT_FILE_FL_FILTERED |
1508  				    EVENT_FILE_FL_PID_FILTER))))
1509  		return false;
1510  
1511  	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1512  		goto discard;
1513  
1514  	if (file->flags & EVENT_FILE_FL_FILTERED &&
1515  	    !filter_match_preds(file->filter, entry))
1516  		goto discard;
1517  
1518  	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1519  	    trace_event_ignore_this_pid(file))
1520  		goto discard;
1521  
1522  	return false;
1523   discard:
1524  	__trace_event_discard_commit(buffer, event);
1525  	return true;
1526  }
1527  
1528  /**
1529   * event_trigger_unlock_commit - handle triggers and finish event commit
1530   * @file: The file pointer associated with the event
1531   * @buffer: The ring buffer that the event is being written to
1532   * @event: The event meta data in the ring buffer
1533   * @entry: The event itself
1534   * @trace_ctx: The tracing context flags.
1535   *
1536   * This is a helper function to handle triggers that require data
1537   * from the event itself. It also tests the event against filters and
1538   * if the event is soft disabled and should be discarded.
1539   */
1540  static inline void
event_trigger_unlock_commit(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,unsigned int trace_ctx)1541  event_trigger_unlock_commit(struct trace_event_file *file,
1542  			    struct trace_buffer *buffer,
1543  			    struct ring_buffer_event *event,
1544  			    void *entry, unsigned int trace_ctx)
1545  {
1546  	enum event_trigger_type tt = ETT_NONE;
1547  
1548  	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1549  		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1550  
1551  	if (tt)
1552  		event_triggers_post_call(file, tt);
1553  }
1554  
1555  #define FILTER_PRED_INVALID	((unsigned short)-1)
1556  #define FILTER_PRED_IS_RIGHT	(1 << 15)
1557  #define FILTER_PRED_FOLD	(1 << 15)
1558  
1559  /*
1560   * The max preds is the size of unsigned short with
1561   * two flags at the MSBs. One bit is used for both the IS_RIGHT
1562   * and FOLD flags. The other is reserved.
1563   *
1564   * 2^14 preds is way more than enough.
1565   */
1566  #define MAX_FILTER_PRED		16384
1567  
1568  struct filter_pred;
1569  struct regex;
1570  
1571  typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1572  
1573  enum regex_type {
1574  	MATCH_FULL = 0,
1575  	MATCH_FRONT_ONLY,
1576  	MATCH_MIDDLE_ONLY,
1577  	MATCH_END_ONLY,
1578  	MATCH_GLOB,
1579  	MATCH_INDEX,
1580  };
1581  
1582  struct regex {
1583  	char			pattern[MAX_FILTER_STR_VAL];
1584  	int			len;
1585  	int			field_len;
1586  	regex_match_func	match;
1587  };
1588  
is_string_field(struct ftrace_event_field * field)1589  static inline bool is_string_field(struct ftrace_event_field *field)
1590  {
1591  	return field->filter_type == FILTER_DYN_STRING ||
1592  	       field->filter_type == FILTER_RDYN_STRING ||
1593  	       field->filter_type == FILTER_STATIC_STRING ||
1594  	       field->filter_type == FILTER_PTR_STRING ||
1595  	       field->filter_type == FILTER_COMM;
1596  }
1597  
is_function_field(struct ftrace_event_field * field)1598  static inline bool is_function_field(struct ftrace_event_field *field)
1599  {
1600  	return field->filter_type == FILTER_TRACE_FN;
1601  }
1602  
1603  extern enum regex_type
1604  filter_parse_regex(char *buff, int len, char **search, int *not);
1605  extern void print_event_filter(struct trace_event_file *file,
1606  			       struct trace_seq *s);
1607  extern int apply_event_filter(struct trace_event_file *file,
1608  			      char *filter_string);
1609  extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1610  					char *filter_string);
1611  extern void print_subsystem_event_filter(struct event_subsystem *system,
1612  					 struct trace_seq *s);
1613  extern int filter_assign_type(const char *type);
1614  extern int create_event_filter(struct trace_array *tr,
1615  			       struct trace_event_call *call,
1616  			       char *filter_str, bool set_str,
1617  			       struct event_filter **filterp);
1618  extern void free_event_filter(struct event_filter *filter);
1619  
1620  struct ftrace_event_field *
1621  trace_find_event_field(struct trace_event_call *call, char *name);
1622  
1623  extern void trace_event_enable_cmd_record(bool enable);
1624  extern void trace_event_enable_tgid_record(bool enable);
1625  
1626  extern int event_trace_init(void);
1627  extern int init_events(void);
1628  extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1629  extern int event_trace_del_tracer(struct trace_array *tr);
1630  extern void __trace_early_add_events(struct trace_array *tr);
1631  
1632  extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1633  						  const char *system,
1634  						  const char *event);
1635  extern struct trace_event_file *find_event_file(struct trace_array *tr,
1636  						const char *system,
1637  						const char *event);
1638  
event_file_data(struct file * filp)1639  static inline void *event_file_data(struct file *filp)
1640  {
1641  	return READ_ONCE(file_inode(filp)->i_private);
1642  }
1643  
1644  extern struct mutex event_mutex;
1645  extern struct list_head ftrace_events;
1646  
1647  /*
1648   * When the trace_event_file is the filp->i_private pointer,
1649   * it must be taken under the event_mutex lock, and then checked
1650   * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1651   * data pointed to by the trace_event_file can not be trusted.
1652   *
1653   * Use the event_file_file() to access the trace_event_file from
1654   * the filp the first time under the event_mutex and check for
1655   * NULL. If it is needed to be retrieved again and the event_mutex
1656   * is still held, then the event_file_data() can be used and it
1657   * is guaranteed to be valid.
1658   */
event_file_file(struct file * filp)1659  static inline struct trace_event_file *event_file_file(struct file *filp)
1660  {
1661  	struct trace_event_file *file;
1662  
1663  	lockdep_assert_held(&event_mutex);
1664  	file = READ_ONCE(file_inode(filp)->i_private);
1665  	if (!file || file->flags & EVENT_FILE_FL_FREED)
1666  		return NULL;
1667  	return file;
1668  }
1669  
1670  extern const struct file_operations event_trigger_fops;
1671  extern const struct file_operations event_hist_fops;
1672  extern const struct file_operations event_hist_debug_fops;
1673  extern const struct file_operations event_inject_fops;
1674  
1675  #ifdef CONFIG_HIST_TRIGGERS
1676  extern int register_trigger_hist_cmd(void);
1677  extern int register_trigger_hist_enable_disable_cmds(void);
1678  #else
register_trigger_hist_cmd(void)1679  static inline int register_trigger_hist_cmd(void) { return 0; }
register_trigger_hist_enable_disable_cmds(void)1680  static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1681  #endif
1682  
1683  extern int register_trigger_cmds(void);
1684  extern void clear_event_triggers(struct trace_array *tr);
1685  
1686  enum {
1687  	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1688  };
1689  
1690  struct event_trigger_data {
1691  	unsigned long			count;
1692  	int				ref;
1693  	int				flags;
1694  	struct event_trigger_ops	*ops;
1695  	struct event_command		*cmd_ops;
1696  	struct event_filter __rcu	*filter;
1697  	char				*filter_str;
1698  	void				*private_data;
1699  	bool				paused;
1700  	bool				paused_tmp;
1701  	struct list_head		list;
1702  	char				*name;
1703  	struct list_head		named_list;
1704  	struct event_trigger_data	*named_data;
1705  };
1706  
1707  /* Avoid typos */
1708  #define ENABLE_EVENT_STR	"enable_event"
1709  #define DISABLE_EVENT_STR	"disable_event"
1710  #define ENABLE_HIST_STR		"enable_hist"
1711  #define DISABLE_HIST_STR	"disable_hist"
1712  
1713  struct enable_trigger_data {
1714  	struct trace_event_file		*file;
1715  	bool				enable;
1716  	bool				hist;
1717  };
1718  
1719  extern int event_enable_trigger_print(struct seq_file *m,
1720  				      struct event_trigger_data *data);
1721  extern void event_enable_trigger_free(struct event_trigger_data *data);
1722  extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1723  				      struct trace_event_file *file,
1724  				      char *glob, char *cmd,
1725  				      char *param_and_filter);
1726  extern int event_enable_register_trigger(char *glob,
1727  					 struct event_trigger_data *data,
1728  					 struct trace_event_file *file);
1729  extern void event_enable_unregister_trigger(char *glob,
1730  					    struct event_trigger_data *test,
1731  					    struct trace_event_file *file);
1732  extern void trigger_data_free(struct event_trigger_data *data);
1733  extern int event_trigger_init(struct event_trigger_data *data);
1734  extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1735  					      int trigger_enable);
1736  extern void update_cond_flag(struct trace_event_file *file);
1737  extern int set_trigger_filter(char *filter_str,
1738  			      struct event_trigger_data *trigger_data,
1739  			      struct trace_event_file *file);
1740  extern struct event_trigger_data *find_named_trigger(const char *name);
1741  extern bool is_named_trigger(struct event_trigger_data *test);
1742  extern int save_named_trigger(const char *name,
1743  			      struct event_trigger_data *data);
1744  extern void del_named_trigger(struct event_trigger_data *data);
1745  extern void pause_named_trigger(struct event_trigger_data *data);
1746  extern void unpause_named_trigger(struct event_trigger_data *data);
1747  extern void set_named_trigger_data(struct event_trigger_data *data,
1748  				   struct event_trigger_data *named_data);
1749  extern struct event_trigger_data *
1750  get_named_trigger_data(struct event_trigger_data *data);
1751  extern int register_event_command(struct event_command *cmd);
1752  extern int unregister_event_command(struct event_command *cmd);
1753  extern int register_trigger_hist_enable_disable_cmds(void);
1754  extern bool event_trigger_check_remove(const char *glob);
1755  extern bool event_trigger_empty_param(const char *param);
1756  extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1757  					 char **filter, bool param_required);
1758  extern struct event_trigger_data *
1759  event_trigger_alloc(struct event_command *cmd_ops,
1760  		    char *cmd,
1761  		    char *param,
1762  		    void *private_data);
1763  extern int event_trigger_parse_num(char *trigger,
1764  				   struct event_trigger_data *trigger_data);
1765  extern int event_trigger_set_filter(struct event_command *cmd_ops,
1766  				    struct trace_event_file *file,
1767  				    char *param,
1768  				    struct event_trigger_data *trigger_data);
1769  extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1770  				       struct event_trigger_data *trigger_data);
1771  extern int event_trigger_register(struct event_command *cmd_ops,
1772  				  struct trace_event_file *file,
1773  				  char *glob,
1774  				  struct event_trigger_data *trigger_data);
1775  extern void event_trigger_unregister(struct event_command *cmd_ops,
1776  				     struct trace_event_file *file,
1777  				     char *glob,
1778  				     struct event_trigger_data *trigger_data);
1779  
1780  extern void event_file_get(struct trace_event_file *file);
1781  extern void event_file_put(struct trace_event_file *file);
1782  
1783  /**
1784   * struct event_trigger_ops - callbacks for trace event triggers
1785   *
1786   * The methods in this structure provide per-event trigger hooks for
1787   * various trigger operations.
1788   *
1789   * The @init and @free methods are used during trigger setup and
1790   * teardown, typically called from an event_command's @parse()
1791   * function implementation.
1792   *
1793   * The @print method is used to print the trigger spec.
1794   *
1795   * The @trigger method is the function that actually implements the
1796   * trigger and is called in the context of the triggering event
1797   * whenever that event occurs.
1798   *
1799   * All the methods below, except for @init() and @free(), must be
1800   * implemented.
1801   *
1802   * @trigger: The trigger 'probe' function called when the triggering
1803   *	event occurs.  The data passed into this callback is the data
1804   *	that was supplied to the event_command @reg() function that
1805   *	registered the trigger (see struct event_command) along with
1806   *	the trace record, rec.
1807   *
1808   * @init: An optional initialization function called for the trigger
1809   *	when the trigger is registered (via the event_command reg()
1810   *	function).  This can be used to perform per-trigger
1811   *	initialization such as incrementing a per-trigger reference
1812   *	count, for instance.  This is usually implemented by the
1813   *	generic utility function @event_trigger_init() (see
1814   *	trace_event_triggers.c).
1815   *
1816   * @free: An optional de-initialization function called for the
1817   *	trigger when the trigger is unregistered (via the
1818   *	event_command @reg() function).  This can be used to perform
1819   *	per-trigger de-initialization such as decrementing a
1820   *	per-trigger reference count and freeing corresponding trigger
1821   *	data, for instance.  This is usually implemented by the
1822   *	generic utility function @event_trigger_free() (see
1823   *	trace_event_triggers.c).
1824   *
1825   * @print: The callback function invoked to have the trigger print
1826   *	itself.  This is usually implemented by a wrapper function
1827   *	that calls the generic utility function @event_trigger_print()
1828   *	(see trace_event_triggers.c).
1829   */
1830  struct event_trigger_ops {
1831  	void			(*trigger)(struct event_trigger_data *data,
1832  					   struct trace_buffer *buffer,
1833  					   void *rec,
1834  					   struct ring_buffer_event *rbe);
1835  	int			(*init)(struct event_trigger_data *data);
1836  	void			(*free)(struct event_trigger_data *data);
1837  	int			(*print)(struct seq_file *m,
1838  					 struct event_trigger_data *data);
1839  };
1840  
1841  /**
1842   * struct event_command - callbacks and data members for event commands
1843   *
1844   * Event commands are invoked by users by writing the command name
1845   * into the 'trigger' file associated with a trace event.  The
1846   * parameters associated with a specific invocation of an event
1847   * command are used to create an event trigger instance, which is
1848   * added to the list of trigger instances associated with that trace
1849   * event.  When the event is hit, the set of triggers associated with
1850   * that event is invoked.
1851   *
1852   * The data members in this structure provide per-event command data
1853   * for various event commands.
1854   *
1855   * All the data members below, except for @post_trigger, must be set
1856   * for each event command.
1857   *
1858   * @name: The unique name that identifies the event command.  This is
1859   *	the name used when setting triggers via trigger files.
1860   *
1861   * @trigger_type: A unique id that identifies the event command
1862   *	'type'.  This value has two purposes, the first to ensure that
1863   *	only one trigger of the same type can be set at a given time
1864   *	for a particular event e.g. it doesn't make sense to have both
1865   *	a traceon and traceoff trigger attached to a single event at
1866   *	the same time, so traceon and traceoff have the same type
1867   *	though they have different names.  The @trigger_type value is
1868   *	also used as a bit value for deferring the actual trigger
1869   *	action until after the current event is finished.  Some
1870   *	commands need to do this if they themselves log to the trace
1871   *	buffer (see the @post_trigger() member below).  @trigger_type
1872   *	values are defined by adding new values to the trigger_type
1873   *	enum in include/linux/trace_events.h.
1874   *
1875   * @flags: See the enum event_command_flags below.
1876   *
1877   * All the methods below, except for @set_filter() and @unreg_all(),
1878   * must be implemented.
1879   *
1880   * @parse: The callback function responsible for parsing and
1881   *	registering the trigger written to the 'trigger' file by the
1882   *	user.  It allocates the trigger instance and registers it with
1883   *	the appropriate trace event.  It makes use of the other
1884   *	event_command callback functions to orchestrate this, and is
1885   *	usually implemented by the generic utility function
1886   *	@event_trigger_callback() (see trace_event_triggers.c).
1887   *
1888   * @reg: Adds the trigger to the list of triggers associated with the
1889   *	event, and enables the event trigger itself, after
1890   *	initializing it (via the event_trigger_ops @init() function).
1891   *	This is also where commands can use the @trigger_type value to
1892   *	make the decision as to whether or not multiple instances of
1893   *	the trigger should be allowed.  This is usually implemented by
1894   *	the generic utility function @register_trigger() (see
1895   *	trace_event_triggers.c).
1896   *
1897   * @unreg: Removes the trigger from the list of triggers associated
1898   *	with the event, and disables the event trigger itself, after
1899   *	initializing it (via the event_trigger_ops @free() function).
1900   *	This is usually implemented by the generic utility function
1901   *	@unregister_trigger() (see trace_event_triggers.c).
1902   *
1903   * @unreg_all: An optional function called to remove all the triggers
1904   *	from the list of triggers associated with the event.  Called
1905   *	when a trigger file is opened in truncate mode.
1906   *
1907   * @set_filter: An optional function called to parse and set a filter
1908   *	for the trigger.  If no @set_filter() method is set for the
1909   *	event command, filters set by the user for the command will be
1910   *	ignored.  This is usually implemented by the generic utility
1911   *	function @set_trigger_filter() (see trace_event_triggers.c).
1912   *
1913   * @get_trigger_ops: The callback function invoked to retrieve the
1914   *	event_trigger_ops implementation associated with the command.
1915   *	This callback function allows a single event_command to
1916   *	support multiple trigger implementations via different sets of
1917   *	event_trigger_ops, depending on the value of the @param
1918   *	string.
1919   */
1920  struct event_command {
1921  	struct list_head	list;
1922  	char			*name;
1923  	enum event_trigger_type	trigger_type;
1924  	int			flags;
1925  	int			(*parse)(struct event_command *cmd_ops,
1926  					 struct trace_event_file *file,
1927  					 char *glob, char *cmd,
1928  					 char *param_and_filter);
1929  	int			(*reg)(char *glob,
1930  				       struct event_trigger_data *data,
1931  				       struct trace_event_file *file);
1932  	void			(*unreg)(char *glob,
1933  					 struct event_trigger_data *data,
1934  					 struct trace_event_file *file);
1935  	void			(*unreg_all)(struct trace_event_file *file);
1936  	int			(*set_filter)(char *filter_str,
1937  					      struct event_trigger_data *data,
1938  					      struct trace_event_file *file);
1939  	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1940  };
1941  
1942  /**
1943   * enum event_command_flags - flags for struct event_command
1944   *
1945   * @POST_TRIGGER: A flag that says whether or not this command needs
1946   *	to have its action delayed until after the current event has
1947   *	been closed.  Some triggers need to avoid being invoked while
1948   *	an event is currently in the process of being logged, since
1949   *	the trigger may itself log data into the trace buffer.  Thus
1950   *	we make sure the current event is committed before invoking
1951   *	those triggers.  To do that, the trigger invocation is split
1952   *	in two - the first part checks the filter using the current
1953   *	trace record; if a command has the @post_trigger flag set, it
1954   *	sets a bit for itself in the return value, otherwise it
1955   *	directly invokes the trigger.  Once all commands have been
1956   *	either invoked or set their return flag, the current record is
1957   *	either committed or discarded.  At that point, if any commands
1958   *	have deferred their triggers, those commands are finally
1959   *	invoked following the close of the current event.  In other
1960   *	words, if the event_trigger_ops @func() probe implementation
1961   *	itself logs to the trace buffer, this flag should be set,
1962   *	otherwise it can be left unspecified.
1963   *
1964   * @NEEDS_REC: A flag that says whether or not this command needs
1965   *	access to the trace record in order to perform its function,
1966   *	regardless of whether or not it has a filter associated with
1967   *	it (filters make a trigger require access to the trace record
1968   *	but are not always present).
1969   */
1970  enum event_command_flags {
1971  	EVENT_CMD_FL_POST_TRIGGER	= 1,
1972  	EVENT_CMD_FL_NEEDS_REC		= 2,
1973  };
1974  
event_command_post_trigger(struct event_command * cmd_ops)1975  static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1976  {
1977  	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1978  }
1979  
event_command_needs_rec(struct event_command * cmd_ops)1980  static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1981  {
1982  	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1983  }
1984  
1985  extern int trace_event_enable_disable(struct trace_event_file *file,
1986  				      int enable, int soft_disable);
1987  extern int tracing_alloc_snapshot(void);
1988  extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1989  extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1990  
1991  extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1992  extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1993  
1994  extern const char *__start___trace_bprintk_fmt[];
1995  extern const char *__stop___trace_bprintk_fmt[];
1996  
1997  extern const char *__start___tracepoint_str[];
1998  extern const char *__stop___tracepoint_str[];
1999  
2000  void trace_printk_control(bool enabled);
2001  void trace_printk_start_comm(void);
2002  int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2003  int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2004  
2005  /* Used from boot time tracer */
2006  extern int trace_set_options(struct trace_array *tr, char *option);
2007  extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2008  extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2009  					  unsigned long size, int cpu_id);
2010  extern int tracing_set_cpumask(struct trace_array *tr,
2011  				cpumask_var_t tracing_cpumask_new);
2012  
2013  
2014  #define MAX_EVENT_NAME_LEN	64
2015  
2016  extern ssize_t trace_parse_run_command(struct file *file,
2017  		const char __user *buffer, size_t count, loff_t *ppos,
2018  		int (*createfn)(const char *));
2019  
2020  extern unsigned int err_pos(char *cmd, const char *str);
2021  extern void tracing_log_err(struct trace_array *tr,
2022  			    const char *loc, const char *cmd,
2023  			    const char **errs, u8 type, u16 pos);
2024  
2025  /*
2026   * Normal trace_printk() and friends allocates special buffers
2027   * to do the manipulation, as well as saves the print formats
2028   * into sections to display. But the trace infrastructure wants
2029   * to use these without the added overhead at the price of being
2030   * a bit slower (used mainly for warnings, where we don't care
2031   * about performance). The internal_trace_puts() is for such
2032   * a purpose.
2033   */
2034  #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2035  
2036  #undef FTRACE_ENTRY
2037  #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2038  	extern struct trace_event_call					\
2039  	__aligned(4) event_##call;
2040  #undef FTRACE_ENTRY_DUP
2041  #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2042  	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2043  #undef FTRACE_ENTRY_PACKED
2044  #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2045  	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2046  
2047  #include "trace_entries.h"
2048  
2049  #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2050  int perf_ftrace_event_register(struct trace_event_call *call,
2051  			       enum trace_reg type, void *data);
2052  #else
2053  #define perf_ftrace_event_register NULL
2054  #endif
2055  
2056  #ifdef CONFIG_FTRACE_SYSCALLS
2057  void init_ftrace_syscalls(void);
2058  const char *get_syscall_name(int syscall);
2059  #else
init_ftrace_syscalls(void)2060  static inline void init_ftrace_syscalls(void) { }
get_syscall_name(int syscall)2061  static inline const char *get_syscall_name(int syscall)
2062  {
2063  	return NULL;
2064  }
2065  #endif
2066  
2067  #ifdef CONFIG_EVENT_TRACING
2068  void trace_event_init(void);
2069  void trace_event_eval_update(struct trace_eval_map **map, int len);
2070  /* Used from boot time tracer */
2071  extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2072  extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2073  #else
trace_event_init(void)2074  static inline void __init trace_event_init(void) { }
trace_event_eval_update(struct trace_eval_map ** map,int len)2075  static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2076  #endif
2077  
2078  #ifdef CONFIG_TRACER_SNAPSHOT
2079  void tracing_snapshot_instance(struct trace_array *tr);
2080  int tracing_alloc_snapshot_instance(struct trace_array *tr);
2081  int tracing_arm_snapshot(struct trace_array *tr);
2082  void tracing_disarm_snapshot(struct trace_array *tr);
2083  #else
tracing_snapshot_instance(struct trace_array * tr)2084  static inline void tracing_snapshot_instance(struct trace_array *tr) { }
tracing_alloc_snapshot_instance(struct trace_array * tr)2085  static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2086  {
2087  	return 0;
2088  }
tracing_arm_snapshot(struct trace_array * tr)2089  static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
tracing_disarm_snapshot(struct trace_array * tr)2090  static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2091  #endif
2092  
2093  #ifdef CONFIG_PREEMPT_TRACER
2094  void tracer_preempt_on(unsigned long a0, unsigned long a1);
2095  void tracer_preempt_off(unsigned long a0, unsigned long a1);
2096  #else
tracer_preempt_on(unsigned long a0,unsigned long a1)2097  static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
tracer_preempt_off(unsigned long a0,unsigned long a1)2098  static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2099  #endif
2100  #ifdef CONFIG_IRQSOFF_TRACER
2101  void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2102  void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2103  #else
tracer_hardirqs_on(unsigned long a0,unsigned long a1)2104  static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
tracer_hardirqs_off(unsigned long a0,unsigned long a1)2105  static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2106  #endif
2107  
2108  /*
2109   * Reset the state of the trace_iterator so that it can read consumed data.
2110   * Normally, the trace_iterator is used for reading the data when it is not
2111   * consumed, and must retain state.
2112   */
trace_iterator_reset(struct trace_iterator * iter)2113  static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2114  {
2115  	memset_startat(iter, 0, seq);
2116  	iter->pos = -1;
2117  }
2118  
2119  /* Check the name is good for event/group/fields */
__is_good_name(const char * name,bool hash_ok)2120  static inline bool __is_good_name(const char *name, bool hash_ok)
2121  {
2122  	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2123  		return false;
2124  	while (*++name != '\0') {
2125  		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2126  		    (!hash_ok || *name != '-'))
2127  			return false;
2128  	}
2129  	return true;
2130  }
2131  
2132  /* Check the name is good for event/group/fields */
is_good_name(const char * name)2133  static inline bool is_good_name(const char *name)
2134  {
2135  	return __is_good_name(name, false);
2136  }
2137  
2138  /* Check the name is good for system */
is_good_system_name(const char * name)2139  static inline bool is_good_system_name(const char *name)
2140  {
2141  	return __is_good_name(name, true);
2142  }
2143  
2144  /* Convert certain expected symbols into '_' when generating event names */
sanitize_event_name(char * name)2145  static inline void sanitize_event_name(char *name)
2146  {
2147  	while (*name++ != '\0')
2148  		if (*name == ':' || *name == '.')
2149  			*name = '_';
2150  }
2151  
2152  /*
2153   * This is a generic way to read and write a u64 value from a file in tracefs.
2154   *
2155   * The value is stored on the variable pointed by *val. The value needs
2156   * to be at least *min and at most *max. The write is protected by an
2157   * existing *lock.
2158   */
2159  struct trace_min_max_param {
2160  	struct mutex	*lock;
2161  	u64		*val;
2162  	u64		*min;
2163  	u64		*max;
2164  };
2165  
2166  #define U64_STR_SIZE		24	/* 20 digits max */
2167  
2168  extern const struct file_operations trace_min_max_fops;
2169  
2170  #ifdef CONFIG_RV
2171  extern int rv_init_interface(void);
2172  #else
rv_init_interface(void)2173  static inline int rv_init_interface(void)
2174  {
2175  	return 0;
2176  }
2177  #endif
2178  
2179  #endif /* _LINUX_KERNEL_TRACE_H */
2180