ftrace: cleanups
[safe/jmp/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 };
27
28 /*
29  * The trace entry - the most basic unit of tracing. This is what
30  * is printed in the end as a single line in the trace output, such as:
31  *
32  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
33  */
34 struct trace_entry {
35         char                    type;
36         char                    cpu;
37         char                    flags;
38         char                    preempt_count;
39         int                     pid;
40         cycle_t                 t;
41         unsigned long           idx;
42         union {
43                 struct ftrace_entry             fn;
44                 struct ctx_switch_entry         ctx;
45         };
46 };
47
48 #define TRACE_ENTRY_SIZE        sizeof(struct trace_entry)
49
50 /*
51  * The CPU trace array - it consists of thousands of trace entries
52  * plus some other descriptor data: (for example which task started
53  * the trace, etc.)
54  */
55 struct trace_array_cpu {
56         void                    *trace_current;
57         struct list_head        trace_pages;
58         atomic_t                disabled;
59         /* these fields get copied into max-trace: */
60         unsigned                trace_current_idx;
61         unsigned long           trace_idx;
62         unsigned long           saved_latency;
63         unsigned long           critical_start;
64         unsigned long           critical_end;
65         unsigned long           critical_sequence;
66         unsigned long           nice;
67         unsigned long           policy;
68         unsigned long           rt_priority;
69         cycle_t                 preempt_timestamp;
70         pid_t                   pid;
71         uid_t                   uid;
72         char                    comm[TASK_COMM_LEN];
73 };
74
75 struct trace_iterator;
76
77 /*
78  * The trace array - an array of per-CPU trace arrays. This is the
79  * highest level data structure that individual tracers deal with.
80  * They have on/off state as well:
81  */
82 struct trace_array {
83         unsigned long           entries;
84         long                    ctrl;
85         int                     cpu;
86         cycle_t                 time_start;
87         struct trace_array_cpu  *data[NR_CPUS];
88 };
89
90 /*
91  * A specific tracer, represented by methods that operate on a trace array:
92  */
93 struct tracer {
94         const char              *name;
95         void                    (*init)(struct trace_array *tr);
96         void                    (*reset)(struct trace_array *tr);
97         void                    (*open)(struct trace_iterator *iter);
98         void                    (*close)(struct trace_iterator *iter);
99         void                    (*start)(struct trace_iterator *iter);
100         void                    (*stop)(struct trace_iterator *iter);
101         void                    (*ctrl_update)(struct trace_array *tr);
102 #ifdef CONFIG_FTRACE_STARTUP_TEST
103         int                     (*selftest)(struct tracer *trace,
104                                             struct trace_array *tr);
105 #endif
106         struct tracer           *next;
107         int                     print_max;
108 };
109
110 /*
111  * Trace iterator - used by printout routines who present trace
112  * results to users and which routines might sleep, etc:
113  */
114 struct trace_iterator {
115         struct trace_array      *tr;
116         struct tracer           *trace;
117         struct trace_entry      *ent;
118         unsigned long           iter_flags;
119         loff_t                  pos;
120         unsigned long           next_idx[NR_CPUS];
121         struct list_head        *next_page[NR_CPUS];
122         unsigned                next_page_idx[NR_CPUS];
123         long                    idx;
124         int                     cpu;
125 };
126
127 void notrace tracing_reset(struct trace_array_cpu *data);
128 int tracing_open_generic(struct inode *inode, struct file *filp);
129 struct dentry *tracing_init_dentry(void);
130 void ftrace(struct trace_array *tr,
131                             struct trace_array_cpu *data,
132                             unsigned long ip,
133                             unsigned long parent_ip,
134                             unsigned long flags);
135 void tracing_sched_switch_trace(struct trace_array *tr,
136                                 struct trace_array_cpu *data,
137                                 struct task_struct *prev,
138                                 struct task_struct *next,
139                                 unsigned long flags);
140 void tracing_record_cmdline(struct task_struct *tsk);
141
142 void tracing_start_function_trace(void);
143 void tracing_stop_function_trace(void);
144 int register_tracer(struct tracer *type);
145 void unregister_tracer(struct tracer *type);
146
147 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
148
149 extern unsigned long tracing_max_latency;
150 extern unsigned long tracing_thresh;
151
152 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
153 void update_max_tr_single(struct trace_array *tr,
154                           struct task_struct *tsk, int cpu);
155
156 static inline notrace cycle_t now(int cpu)
157 {
158         return cpu_clock(cpu);
159 }
160
161 #ifdef CONFIG_SCHED_TRACER
162 extern void notrace
163 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next);
164 #else
165 static inline void
166 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
167 {
168 }
169 #endif
170
171 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
172 typedef void
173 (*tracer_switch_func_t)(void *private,
174                         struct task_struct *prev,
175                         struct task_struct *next);
176
177 struct tracer_switch_ops {
178         tracer_switch_func_t            func;
179         void                            *private;
180         struct tracer_switch_ops        *next;
181 };
182
183 extern int register_tracer_switch(struct tracer_switch_ops *ops);
184 extern int unregister_tracer_switch(struct tracer_switch_ops *ops);
185
186 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
187
188 #ifdef CONFIG_DYNAMIC_FTRACE
189 extern unsigned long ftrace_update_tot_cnt;
190 #endif
191
192 #ifdef CONFIG_FTRACE_STARTUP_TEST
193 #ifdef CONFIG_FTRACE
194 extern int trace_selftest_startup_function(struct tracer *trace,
195                                            struct trace_array *tr);
196 #endif
197 #ifdef CONFIG_IRQSOFF_TRACER
198 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
199                                           struct trace_array *tr);
200 #endif
201 #ifdef CONFIG_PREEMPT_TRACER
202 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
203                                              struct trace_array *tr);
204 #endif
205 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
206 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
207                                                  struct trace_array *tr);
208 #endif
209 #ifdef CONFIG_SCHED_TRACER
210 extern int trace_selftest_startup_wakeup(struct tracer *trace,
211                                          struct trace_array *tr);
212 #endif
213 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
214 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
215                                                struct trace_array *tr);
216 #endif
217 #endif /* CONFIG_FTRACE_STARTUP_TEST */
218
219 extern void *head_page(struct trace_array_cpu *data);
220
221 #endif /* _LINUX_KERNEL_TRACE_H */