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;
  57         void                    *trace_current;
  58         unsigned                trace_current_idx;
  59         struct list_head        trace_pages;
  60         unsigned long           trace_idx;
  61         atomic_t                disabled;
  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 #endif /* _LINUX_KERNEL_TRACE_H */