ftrace: restrict tracing to HAVE_FTRACE architectures
[linux-2.6] / kernel / trace / trace.h
1 #ifndef _LINUX_KERNEL_TRACE_H
2 #define _LINUX_KERNEL_TRACE_H
3
4 #include <linux/fs.h>
5 #include <asm/atomic.h>
6 #include <linux/sched.h>
7 #include <linux/clocksource.h>
8
9 /*
10  * Function trace entry - function address and parent function addres:
11  */
12 struct ftrace_entry {
13         unsigned long           ip;
14         unsigned long           parent_ip;
15 };
16
17 /*
18  * Context switch trace entry - which task (and prio) we switched from/to:
19  */
20 struct ctx_switch_entry {
21         unsigned int            prev_pid;
22         unsigned char           prev_prio;
23         unsigned char           prev_state;
24         unsigned int            next_pid;
25         unsigned char           next_prio;
26         unsigned char           next_state;
27 };
28
29 /*
30  * Special (free-form) trace entry:
31  */
32 struct special_entry {
33         unsigned long           arg1;
34         unsigned long           arg2;
35         unsigned long           arg3;
36 };
37
38 /*
39  * Stack-trace entry:
40  */
41
42 #define FTRACE_STACK_ENTRIES    5
43
44 struct stack_entry {
45         unsigned long           caller[FTRACE_STACK_ENTRIES];
46 };
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  */
54 struct trace_entry {
55         char                    type;
56         char                    cpu;
57         char                    flags;
58         char                    preempt_count;
59         int                     pid;
60         cycle_t                 t;
61         union {
62                 struct ftrace_entry             fn;
63                 struct ctx_switch_entry         ctx;
64                 struct special_entry            special;
65                 struct stack_entry              stack;
66         };
67 };
68
69 #define TRACE_ENTRY_SIZE        sizeof(struct trace_entry)
70
71 /*
72  * The CPU trace array - it consists of thousands of trace entries
73  * plus some other descriptor data: (for example which task started
74  * the trace, etc.)
75  */
76 struct trace_array_cpu {
77         struct list_head        trace_pages;
78         atomic_t                disabled;
79         raw_spinlock_t          lock;
80         struct lock_class_key   lock_key;
81
82         /* these fields get copied into max-trace: */
83         unsigned                trace_head_idx;
84         unsigned                trace_tail_idx;
85         void                    *trace_head; /* producer */
86         void                    *trace_tail; /* consumer */
87         unsigned long           trace_idx;
88         unsigned long           saved_latency;
89         unsigned long           critical_start;
90         unsigned long           critical_end;
91         unsigned long           critical_sequence;
92         unsigned long           nice;
93         unsigned long           policy;
94         unsigned long           rt_priority;
95         cycle_t                 preempt_timestamp;
96         pid_t                   pid;
97         uid_t                   uid;
98         char                    comm[TASK_COMM_LEN];
99 };
100
101 struct trace_iterator;
102
103 /*
104  * The trace array - an array of per-CPU trace arrays. This is the
105  * highest level data structure that individual tracers deal with.
106  * They have on/off state as well:
107  */
108 struct trace_array {
109         unsigned long           entries;
110         long                    ctrl;
111         int                     cpu;
112         cycle_t                 time_start;
113         struct task_struct      *waiter;
114         struct trace_array_cpu  *data[NR_CPUS];
115 };
116
117 /*
118  * A specific tracer, represented by methods that operate on a trace array:
119  */
120 struct tracer {
121         const char              *name;
122         void                    (*init)(struct trace_array *tr);
123         void                    (*reset)(struct trace_array *tr);
124         void                    (*open)(struct trace_iterator *iter);
125         void                    (*close)(struct trace_iterator *iter);
126         void                    (*start)(struct trace_iterator *iter);
127         void                    (*stop)(struct trace_iterator *iter);
128         void                    (*ctrl_update)(struct trace_array *tr);
129 #ifdef CONFIG_FTRACE_STARTUP_TEST
130         int                     (*selftest)(struct tracer *trace,
131                                             struct trace_array *tr);
132 #endif
133         struct tracer           *next;
134         int                     print_max;
135 };
136
137 struct trace_seq {
138         unsigned char           buffer[PAGE_SIZE];
139         unsigned int            len;
140 };
141
142 /*
143  * Trace iterator - used by printout routines who present trace
144  * results to users and which routines might sleep, etc:
145  */
146 struct trace_iterator {
147         struct trace_seq        seq;
148         struct trace_array      *tr;
149         struct tracer           *trace;
150
151         struct trace_entry      *ent;
152         int                     cpu;
153
154         struct trace_entry      *prev_ent;
155         int                     prev_cpu;
156
157         unsigned long           iter_flags;
158         loff_t                  pos;
159         unsigned long           next_idx[NR_CPUS];
160         struct list_head        *next_page[NR_CPUS];
161         unsigned                next_page_idx[NR_CPUS];
162         long                    idx;
163 };
164
165 void tracing_reset(struct trace_array_cpu *data);
166 int tracing_open_generic(struct inode *inode, struct file *filp);
167 struct dentry *tracing_init_dentry(void);
168 void ftrace(struct trace_array *tr,
169                             struct trace_array_cpu *data,
170                             unsigned long ip,
171                             unsigned long parent_ip,
172                             unsigned long flags);
173 void tracing_sched_switch_trace(struct trace_array *tr,
174                                 struct trace_array_cpu *data,
175                                 struct task_struct *prev,
176                                 struct task_struct *next,
177                                 unsigned long flags);
178 void tracing_record_cmdline(struct task_struct *tsk);
179
180 void tracing_sched_wakeup_trace(struct trace_array *tr,
181                                 struct trace_array_cpu *data,
182                                 struct task_struct *wakee,
183                                 struct task_struct *cur,
184                                 unsigned long flags);
185 void trace_special(struct trace_array *tr,
186                    struct trace_array_cpu *data,
187                    unsigned long arg1,
188                    unsigned long arg2,
189                    unsigned long arg3);
190 void trace_function(struct trace_array *tr,
191                     struct trace_array_cpu *data,
192                     unsigned long ip,
193                     unsigned long parent_ip,
194                     unsigned long flags);
195
196 void tracing_start_function_trace(void);
197 void tracing_stop_function_trace(void);
198 int register_tracer(struct tracer *type);
199 void unregister_tracer(struct tracer *type);
200
201 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
202
203 extern unsigned long tracing_max_latency;
204 extern unsigned long tracing_thresh;
205
206 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
207 void update_max_tr_single(struct trace_array *tr,
208                           struct task_struct *tsk, int cpu);
209
210 extern cycle_t ftrace_now(int cpu);
211
212 #ifdef CONFIG_SCHED_TRACER
213 extern void
214 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next);
215 extern void
216 wakeup_sched_wakeup(struct task_struct *wakee, struct task_struct *curr);
217 #else
218 static inline void
219 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
220 {
221 }
222 static inline void
223 wakeup_sched_wakeup(struct task_struct *wakee, struct task_struct *curr)
224 {
225 }
226 #endif
227
228 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
229 typedef void
230 (*tracer_switch_func_t)(void *private,
231                         struct task_struct *prev,
232                         struct task_struct *next);
233
234 struct tracer_switch_ops {
235         tracer_switch_func_t            func;
236         void                            *private;
237         struct tracer_switch_ops        *next;
238 };
239
240 extern int register_tracer_switch(struct tracer_switch_ops *ops);
241 extern int unregister_tracer_switch(struct tracer_switch_ops *ops);
242
243 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
244
245 #ifdef CONFIG_DYNAMIC_FTRACE
246 extern unsigned long ftrace_update_tot_cnt;
247 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
248 extern int DYN_FTRACE_TEST_NAME(void);
249 #endif
250
251 #ifdef CONFIG_FTRACE_STARTUP_TEST
252 #ifdef CONFIG_FTRACE
253 extern int trace_selftest_startup_function(struct tracer *trace,
254                                            struct trace_array *tr);
255 #endif
256 #ifdef CONFIG_IRQSOFF_TRACER
257 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
258                                           struct trace_array *tr);
259 #endif
260 #ifdef CONFIG_PREEMPT_TRACER
261 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
262                                              struct trace_array *tr);
263 #endif
264 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
265 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
266                                                  struct trace_array *tr);
267 #endif
268 #ifdef CONFIG_SCHED_TRACER
269 extern int trace_selftest_startup_wakeup(struct tracer *trace,
270                                          struct trace_array *tr);
271 #endif
272 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
273 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
274                                                struct trace_array *tr);
275 #endif
276 #endif /* CONFIG_FTRACE_STARTUP_TEST */
277
278 extern void *head_page(struct trace_array_cpu *data);
279
280 extern unsigned long trace_flags;
281
282 enum trace_iterator_flags {
283         TRACE_ITER_PRINT_PARENT         = 0x01,
284         TRACE_ITER_SYM_OFFSET           = 0x02,
285         TRACE_ITER_SYM_ADDR             = 0x04,
286         TRACE_ITER_VERBOSE              = 0x08,
287         TRACE_ITER_RAW                  = 0x10,
288         TRACE_ITER_HEX                  = 0x20,
289         TRACE_ITER_BIN                  = 0x40,
290         TRACE_ITER_BLOCK                = 0x80,
291         TRACE_ITER_STACKTRACE           = 0x100,
292         TRACE_ITER_SCHED_TREE           = 0x200,
293 };
294
295 #endif /* _LINUX_KERNEL_TRACE_H */