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         cycle_t                 time_offset;
  60
  61         /* these fields get copied into max-trace: */
  62         unsigned                trace_current_idx;
  63         unsigned long           trace_idx;
  64         unsigned long           saved_latency;
  65         unsigned long           critical_start;
  66         unsigned long           critical_end;
  67         unsigned long           critical_sequence;
  68         unsigned long           nice;
  69         unsigned long           policy;
  70         unsigned long           rt_priority;
  71         cycle_t                 preempt_timestamp;
  72         pid_t                   pid;
  73         uid_t                   uid;
  74         char                    comm[TASK_COMM_LEN];
  75 };
  76
  77 struct trace_iterator;
  78
  79 /*
  80  * The trace array - an array of per-CPU trace arrays. This is the
  81  * highest level data structure that individual tracers deal with.
  82  * They have on/off state as well:
  83  */
  84 struct trace_array {
  85         unsigned long           entries;
  86         long                    ctrl;
  87         int                     cpu;
  88         cycle_t                 time_start;
  89         struct trace_array_cpu  *data[NR_CPUS];
  90 };
  91
  92 /*
  93  * A specific tracer, represented by methods that operate on a trace array:
  94  */
  95 struct tracer {
  96         const char              *name;
  97         void                    (*init)(struct trace_array *tr);
  98         void                    (*reset)(struct trace_array *tr);
  99         void                    (*open)(struct trace_iterator *iter);
 100         void                    (*close)(struct trace_iterator *iter);
 101         void                    (*start)(struct trace_iterator *iter);
 102         void                    (*stop)(struct trace_iterator *iter);
 103         void                    (*ctrl_update)(struct trace_array *tr);
 104 #ifdef CONFIG_FTRACE_STARTUP_TEST
 105         int                     (*selftest)(struct tracer *trace,
 106                                             struct trace_array *tr);
 107 #endif
 108         struct tracer           *next;
 109         int                     print_max;
 110 };
 111
 112 /*
 113  * Trace iterator - used by printout routines who present trace
 114  * results to users and which routines might sleep, etc:
 115  */
 116 struct trace_iterator {
 117         struct trace_array      *tr;
 118         struct tracer           *trace;
 119
 120         struct trace_entry      *ent;
 121         int                     cpu;
 122
 123         struct trace_entry      *prev_ent;
 124         int                     prev_cpu;
 125
 126         unsigned long           iter_flags;
 127         loff_t                  pos;
 128         unsigned long           next_idx[NR_CPUS];
 129         struct list_head        *next_page[NR_CPUS];
 130         unsigned                next_page_idx[NR_CPUS];
 131         long                    idx;
 132 };
 133
 134 void notrace tracing_reset(struct trace_array_cpu *data);
 135 int tracing_open_generic(struct inode *inode, struct file *filp);
 136 struct dentry *tracing_init_dentry(void);
 137 void ftrace(struct trace_array *tr,
 138                             struct trace_array_cpu *data,
 139                             unsigned long ip,
 140                             unsigned long parent_ip,
 141                             unsigned long flags);
 142 void tracing_sched_switch_trace(struct trace_array *tr,
 143                                 struct trace_array_cpu *data,
 144                                 struct task_struct *prev,
 145                                 struct task_struct *next,
 146                                 unsigned long flags);
 147 void tracing_record_cmdline(struct task_struct *tsk);
 148
 149 void tracing_start_function_trace(void);
 150 void tracing_stop_function_trace(void);
 151 int register_tracer(struct tracer *type);
 152 void unregister_tracer(struct tracer *type);
 153
 154 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 155
 156 extern unsigned long tracing_max_latency;
 157 extern unsigned long tracing_thresh;
 158
 159 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 160 void update_max_tr_single(struct trace_array *tr,
 161                           struct task_struct *tsk, int cpu);
 162
 163 static inline notrace cycle_t now(int cpu)
 164 {
 165         return cpu_clock(cpu);
 166 }
 167
 168 #ifdef CONFIG_SCHED_TRACER
 169 extern void notrace
 170 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next);
 171 #else
 172 static inline void
 173 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
 174 {
 175 }
 176 #endif
 177
 178 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 179 typedef void
 180 (*tracer_switch_func_t)(void *private,
 181                         struct task_struct *prev,
 182                         struct task_struct *next);
 183
 184 struct tracer_switch_ops {
 185         tracer_switch_func_t            func;
 186         void                            *private;
 187         struct tracer_switch_ops        *next;
 188 };
 189
 190 extern int register_tracer_switch(struct tracer_switch_ops *ops);
 191 extern int unregister_tracer_switch(struct tracer_switch_ops *ops);
 192
 193 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
 194
 195 #ifdef CONFIG_DYNAMIC_FTRACE
 196 extern unsigned long ftrace_update_tot_cnt;
 197 #endif
 198
 199 #ifdef CONFIG_FTRACE_STARTUP_TEST
 200 #ifdef CONFIG_FTRACE
 201 extern int trace_selftest_startup_function(struct tracer *trace,
 202                                            struct trace_array *tr);
 203 #endif
 204 #ifdef CONFIG_IRQSOFF_TRACER
 205 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 206                                           struct trace_array *tr);
 207 #endif
 208 #ifdef CONFIG_PREEMPT_TRACER
 209 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 210                                              struct trace_array *tr);
 211 #endif
 212 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
 213 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 214                                                  struct trace_array *tr);
 215 #endif
 216 #ifdef CONFIG_SCHED_TRACER
 217 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 218                                          struct trace_array *tr);
 219 #endif
 220 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 221 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 222                                                struct trace_array *tr);
 223 #endif
 224 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 225
 226 extern void *head_page(struct trace_array_cpu *data);
 227
 228 #endif /* _LINUX_KERNEL_TRACE_H */