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Linux kernel mirror (for testing)
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linux
1#ifndef _LINUX_FTRACE_EVENT_H
2#define _LINUX_FTRACE_EVENT_H
3
4#include <linux/ring_buffer.h>
5#include <linux/trace_seq.h>
6#include <linux/percpu.h>
7#include <linux/hardirq.h>
8#include <linux/perf_event.h>
9
10struct trace_array;
11struct trace_buffer;
12struct tracer;
13struct dentry;
14
15struct trace_print_flags {
16 unsigned long mask;
17 const char *name;
18};
19
20struct trace_print_flags_u64 {
21 unsigned long long mask;
22 const char *name;
23};
24
25const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
26 unsigned long flags,
27 const struct trace_print_flags *flag_array);
28
29const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
30 const struct trace_print_flags *symbol_array);
31
32#if BITS_PER_LONG == 32
33const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
34 unsigned long long val,
35 const struct trace_print_flags_u64
36 *symbol_array);
37#endif
38
39const char *ftrace_print_hex_seq(struct trace_seq *p,
40 const unsigned char *buf, int len);
41
42struct trace_iterator;
43struct trace_event;
44
45int ftrace_raw_output_prep(struct trace_iterator *iter,
46 struct trace_event *event);
47
48/*
49 * The trace entry - the most basic unit of tracing. This is what
50 * is printed in the end as a single line in the trace output, such as:
51 *
52 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
53 */
54struct trace_entry {
55 unsigned short type;
56 unsigned char flags;
57 unsigned char preempt_count;
58 int pid;
59};
60
61#define FTRACE_MAX_EVENT \
62 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
63
64/*
65 * Trace iterator - used by printout routines who present trace
66 * results to users and which routines might sleep, etc:
67 */
68struct trace_iterator {
69 struct trace_array *tr;
70 struct tracer *trace;
71 struct trace_buffer *trace_buffer;
72 void *private;
73 int cpu_file;
74 struct mutex mutex;
75 struct ring_buffer_iter **buffer_iter;
76 unsigned long iter_flags;
77
78 /* trace_seq for __print_flags() and __print_symbolic() etc. */
79 struct trace_seq tmp_seq;
80
81 /* The below is zeroed out in pipe_read */
82 struct trace_seq seq;
83 struct trace_entry *ent;
84 unsigned long lost_events;
85 int leftover;
86 int ent_size;
87 int cpu;
88 u64 ts;
89
90 loff_t pos;
91 long idx;
92
93 cpumask_var_t started;
94
95 /* it's true when current open file is snapshot */
96 bool snapshot;
97};
98
99enum trace_iter_flags {
100 TRACE_FILE_LAT_FMT = 1,
101 TRACE_FILE_ANNOTATE = 2,
102 TRACE_FILE_TIME_IN_NS = 4,
103};
104
105
106typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
107 int flags, struct trace_event *event);
108
109struct trace_event_functions {
110 trace_print_func trace;
111 trace_print_func raw;
112 trace_print_func hex;
113 trace_print_func binary;
114};
115
116struct trace_event {
117 struct hlist_node node;
118 struct list_head list;
119 int type;
120 struct trace_event_functions *funcs;
121};
122
123extern int register_ftrace_event(struct trace_event *event);
124extern int unregister_ftrace_event(struct trace_event *event);
125
126/* Return values for print_line callback */
127enum print_line_t {
128 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
129 TRACE_TYPE_HANDLED = 1,
130 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */
131 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */
132};
133
134void tracing_generic_entry_update(struct trace_entry *entry,
135 unsigned long flags,
136 int pc);
137struct ftrace_event_file;
138
139struct ring_buffer_event *
140trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
141 struct ftrace_event_file *ftrace_file,
142 int type, unsigned long len,
143 unsigned long flags, int pc);
144struct ring_buffer_event *
145trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
146 int type, unsigned long len,
147 unsigned long flags, int pc);
148void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
149 struct ring_buffer_event *event,
150 unsigned long flags, int pc);
151void trace_buffer_unlock_commit(struct ring_buffer *buffer,
152 struct ring_buffer_event *event,
153 unsigned long flags, int pc);
154void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
155 struct ring_buffer_event *event,
156 unsigned long flags, int pc,
157 struct pt_regs *regs);
158void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
159 struct ring_buffer_event *event);
160
161void tracing_record_cmdline(struct task_struct *tsk);
162
163struct event_filter;
164
165enum trace_reg {
166 TRACE_REG_REGISTER,
167 TRACE_REG_UNREGISTER,
168#ifdef CONFIG_PERF_EVENTS
169 TRACE_REG_PERF_REGISTER,
170 TRACE_REG_PERF_UNREGISTER,
171 TRACE_REG_PERF_OPEN,
172 TRACE_REG_PERF_CLOSE,
173 TRACE_REG_PERF_ADD,
174 TRACE_REG_PERF_DEL,
175#endif
176};
177
178struct ftrace_event_call;
179
180struct ftrace_event_class {
181 char *system;
182 void *probe;
183#ifdef CONFIG_PERF_EVENTS
184 void *perf_probe;
185#endif
186 int (*reg)(struct ftrace_event_call *event,
187 enum trace_reg type, void *data);
188 int (*define_fields)(struct ftrace_event_call *);
189 struct list_head *(*get_fields)(struct ftrace_event_call *);
190 struct list_head fields;
191 int (*raw_init)(struct ftrace_event_call *);
192};
193
194extern int ftrace_event_reg(struct ftrace_event_call *event,
195 enum trace_reg type, void *data);
196
197enum {
198 TRACE_EVENT_FL_FILTERED_BIT,
199 TRACE_EVENT_FL_CAP_ANY_BIT,
200 TRACE_EVENT_FL_NO_SET_FILTER_BIT,
201 TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
202 TRACE_EVENT_FL_WAS_ENABLED_BIT,
203};
204
205/*
206 * Event flags:
207 * FILTERED - The event has a filter attached
208 * CAP_ANY - Any user can enable for perf
209 * NO_SET_FILTER - Set when filter has error and is to be ignored
210 * IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file
211 * WAS_ENABLED - Set and stays set when an event was ever enabled
212 * (used for module unloading, if a module event is enabled,
213 * it is best to clear the buffers that used it).
214 */
215enum {
216 TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
217 TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
218 TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
219 TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
220 TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
221};
222
223struct ftrace_event_call {
224 struct list_head list;
225 struct ftrace_event_class *class;
226 char *name;
227 struct trace_event event;
228 const char *print_fmt;
229 struct event_filter *filter;
230 struct list_head *files;
231 void *mod;
232 void *data;
233 /*
234 * bit 0: filter_active
235 * bit 1: allow trace by non root (cap any)
236 * bit 2: failed to apply filter
237 * bit 3: ftrace internal event (do not enable)
238 * bit 4: Event was enabled by module
239 */
240 int flags; /* static flags of different events */
241
242#ifdef CONFIG_PERF_EVENTS
243 int perf_refcount;
244 struct hlist_head __percpu *perf_events;
245#endif
246};
247
248struct trace_array;
249struct ftrace_subsystem_dir;
250
251enum {
252 FTRACE_EVENT_FL_ENABLED_BIT,
253 FTRACE_EVENT_FL_RECORDED_CMD_BIT,
254 FTRACE_EVENT_FL_SOFT_MODE_BIT,
255 FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
256};
257
258/*
259 * Ftrace event file flags:
260 * ENABLED - The event is enabled
261 * RECORDED_CMD - The comms should be recorded at sched_switch
262 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
263 * SOFT_DISABLED - When set, do not trace the event (even though its
264 * tracepoint may be enabled)
265 */
266enum {
267 FTRACE_EVENT_FL_ENABLED = (1 << FTRACE_EVENT_FL_ENABLED_BIT),
268 FTRACE_EVENT_FL_RECORDED_CMD = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT),
269 FTRACE_EVENT_FL_SOFT_MODE = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT),
270 FTRACE_EVENT_FL_SOFT_DISABLED = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT),
271};
272
273struct ftrace_event_file {
274 struct list_head list;
275 struct ftrace_event_call *event_call;
276 struct dentry *dir;
277 struct trace_array *tr;
278 struct ftrace_subsystem_dir *system;
279
280 /*
281 * 32 bit flags:
282 * bit 0: enabled
283 * bit 1: enabled cmd record
284 * bit 2: enable/disable with the soft disable bit
285 * bit 3: soft disabled
286 *
287 * Note: The bits must be set atomically to prevent races
288 * from other writers. Reads of flags do not need to be in
289 * sync as they occur in critical sections. But the way flags
290 * is currently used, these changes do not affect the code
291 * except that when a change is made, it may have a slight
292 * delay in propagating the changes to other CPUs due to
293 * caching and such. Which is mostly OK ;-)
294 */
295 unsigned long flags;
296 atomic_t sm_ref; /* soft-mode reference counter */
297};
298
299#define __TRACE_EVENT_FLAGS(name, value) \
300 static int __init trace_init_flags_##name(void) \
301 { \
302 event_##name.flags = value; \
303 return 0; \
304 } \
305 early_initcall(trace_init_flags_##name);
306
307#define PERF_MAX_TRACE_SIZE 2048
308
309#define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
310
311extern void destroy_preds(struct ftrace_event_call *call);
312extern int filter_match_preds(struct event_filter *filter, void *rec);
313extern int filter_current_check_discard(struct ring_buffer *buffer,
314 struct ftrace_event_call *call,
315 void *rec,
316 struct ring_buffer_event *event);
317
318enum {
319 FILTER_OTHER = 0,
320 FILTER_STATIC_STRING,
321 FILTER_DYN_STRING,
322 FILTER_PTR_STRING,
323 FILTER_TRACE_FN,
324};
325
326#define EVENT_STORAGE_SIZE 128
327extern struct mutex event_storage_mutex;
328extern char event_storage[EVENT_STORAGE_SIZE];
329
330extern int trace_event_raw_init(struct ftrace_event_call *call);
331extern int trace_define_field(struct ftrace_event_call *call, const char *type,
332 const char *name, int offset, int size,
333 int is_signed, int filter_type);
334extern int trace_add_event_call(struct ftrace_event_call *call);
335extern void trace_remove_event_call(struct ftrace_event_call *call);
336
337#define is_signed_type(type) (((type)(-1)) < (type)1)
338
339int trace_set_clr_event(const char *system, const char *event, int set);
340
341/*
342 * The double __builtin_constant_p is because gcc will give us an error
343 * if we try to allocate the static variable to fmt if it is not a
344 * constant. Even with the outer if statement optimizing out.
345 */
346#define event_trace_printk(ip, fmt, args...) \
347do { \
348 __trace_printk_check_format(fmt, ##args); \
349 tracing_record_cmdline(current); \
350 if (__builtin_constant_p(fmt)) { \
351 static const char *trace_printk_fmt \
352 __attribute__((section("__trace_printk_fmt"))) = \
353 __builtin_constant_p(fmt) ? fmt : NULL; \
354 \
355 __trace_bprintk(ip, trace_printk_fmt, ##args); \
356 } else \
357 __trace_printk(ip, fmt, ##args); \
358} while (0)
359
360#ifdef CONFIG_PERF_EVENTS
361struct perf_event;
362
363DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
364
365extern int perf_trace_init(struct perf_event *event);
366extern void perf_trace_destroy(struct perf_event *event);
367extern int perf_trace_add(struct perf_event *event, int flags);
368extern void perf_trace_del(struct perf_event *event, int flags);
369extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
370 char *filter_str);
371extern void ftrace_profile_free_filter(struct perf_event *event);
372extern void *perf_trace_buf_prepare(int size, unsigned short type,
373 struct pt_regs *regs, int *rctxp);
374
375static inline void
376perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
377 u64 count, struct pt_regs *regs, void *head,
378 struct task_struct *task)
379{
380 perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
381}
382#endif
383
384#endif /* _LINUX_FTRACE_EVENT_H */