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         struct list_head        trace_pages;
  57         atomic_t                disabled;
  58         spinlock_t              lock;
  59         struct lock_class_key   lock_key;
  60         cycle_t                 time_offset;
  61
  62         /* these fields get copied into max-trace: */
  63         unsigned                trace_head_idx;
  64         unsigned                trace_tail_idx;
  65         void                    *trace_head; /* producer */
  66         void                    *trace_tail; /* consumer */
  67         unsigned long           trace_idx;
  68         unsigned long           saved_latency;
  69         unsigned long           critical_start;
  70         unsigned long           critical_end;
  71         unsigned long           critical_sequence;
  72         unsigned long           nice;
  73         unsigned long           policy;
  74         unsigned long           rt_priority;
  75         cycle_t                 preempt_timestamp;
  76         pid_t                   pid;
  77         uid_t                   uid;
  78         char                    comm[TASK_COMM_LEN];
  79 };
  80
  81 struct trace_iterator;
  82
  83 /*
  84  * The trace array - an array of per-CPU trace arrays. This is the
  85  * highest level data structure that individual tracers deal with.
  86  * They have on/off state as well:
  87  */
  88 struct trace_array {
  89         unsigned long           entries;
  90         long                    ctrl;
  91         int                     cpu;
  92         cycle_t                 time_start;
  93         struct task_struct      *waiter;
  94         struct trace_array_cpu  *data[NR_CPUS];
  95 };
  96
  97 /*
  98  * A specific tracer, represented by methods that operate on a trace array:
  99  */
 100 struct tracer {
 101         const char              *name;
 102         void                    (*init)(struct trace_array *tr);
 103         void                    (*reset)(struct trace_array *tr);
 104         void                    (*open)(struct trace_iterator *iter);
 105         void                    (*close)(struct trace_iterator *iter);
 106         void                    (*start)(struct trace_iterator *iter);
 107         void                    (*stop)(struct trace_iterator *iter);
 108         void                    (*ctrl_update)(struct trace_array *tr);
 109 #ifdef CONFIG_FTRACE_STARTUP_TEST
 110         int                     (*selftest)(struct tracer *trace,
 111                                             struct trace_array *tr);
 112 #endif
 113         struct tracer           *next;
 114         int                     print_max;
 115 };
 116
 117 struct trace_seq {
 118         unsigned char           buffer[PAGE_SIZE];
 119         unsigned int            len;
 120 };
 121
 122 /*
 123  * Trace iterator - used by printout routines who present trace
 124  * results to users and which routines might sleep, etc:
 125  */
 126 struct trace_iterator {
 127         struct trace_seq        seq;
 128         struct trace_array      *tr;
 129         struct tracer           *trace;
 130
 131         struct trace_entry      *ent;
 132         int                     cpu;
 133
 134         struct trace_entry      *prev_ent;
 135         int                     prev_cpu;
 136
 137         unsigned long           iter_flags;
 138         loff_t                  pos;
 139         unsigned long           next_idx[NR_CPUS];
 140         struct list_head        *next_page[NR_CPUS];
 141         unsigned                next_page_idx[NR_CPUS];
 142         long                    idx;
 143 };
 144
 145 void notrace tracing_reset(struct trace_array_cpu *data);
 146 int tracing_open_generic(struct inode *inode, struct file *filp);
 147 struct dentry *tracing_init_dentry(void);
 148 void ftrace(struct trace_array *tr,
 149                             struct trace_array_cpu *data,
 150                             unsigned long ip,
 151                             unsigned long parent_ip,
 152                             unsigned long flags);
 153 void tracing_sched_switch_trace(struct trace_array *tr,
 154                                 struct trace_array_cpu *data,
 155                                 struct task_struct *prev,
 156                                 struct task_struct *next,
 157                                 unsigned long flags);
 158 void tracing_record_cmdline(struct task_struct *tsk);
 159
 160 void tracing_start_function_trace(void);
 161 void tracing_stop_function_trace(void);
 162 int register_tracer(struct tracer *type);
 163 void unregister_tracer(struct tracer *type);
 164
 165 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 166
 167 extern unsigned long tracing_max_latency;
 168 extern unsigned long tracing_thresh;
 169
 170 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 171 void update_max_tr_single(struct trace_array *tr,
 172                           struct task_struct *tsk, int cpu);
 173
 174 extern notrace cycle_t ftrace_now(int cpu);
 175
 176 #ifdef CONFIG_SCHED_TRACER
 177 extern void notrace
 178 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next);
 179 #else
 180 static inline void
 181 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
 182 {
 183 }
 184 #endif
 185
 186 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 187 typedef void
 188 (*tracer_switch_func_t)(void *private,
 189                         struct task_struct *prev,
 190                         struct task_struct *next);
 191
 192 struct tracer_switch_ops {
 193         tracer_switch_func_t            func;
 194         void                            *private;
 195         struct tracer_switch_ops        *next;
 196 };
 197
 198 extern int register_tracer_switch(struct tracer_switch_ops *ops);
 199 extern int unregister_tracer_switch(struct tracer_switch_ops *ops);
 200
 201 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
 202
 203 #ifdef CONFIG_DYNAMIC_FTRACE
 204 extern unsigned long ftrace_update_tot_cnt;
 205 #endif
 206
 207 #ifdef CONFIG_FTRACE_STARTUP_TEST
 208 #ifdef CONFIG_FTRACE
 209 extern int trace_selftest_startup_function(struct tracer *trace,
 210                                            struct trace_array *tr);
 211 #endif
 212 #ifdef CONFIG_IRQSOFF_TRACER
 213 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 214                                           struct trace_array *tr);
 215 #endif
 216 #ifdef CONFIG_PREEMPT_TRACER
 217 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 218                                              struct trace_array *tr);
 219 #endif
 220 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
 221 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 222                                                  struct trace_array *tr);
 223 #endif
 224 #ifdef CONFIG_SCHED_TRACER
 225 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 226                                          struct trace_array *tr);
 227 #endif
 228 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 229 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 230                                                struct trace_array *tr);
 231 #endif
 232 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 233
 234 extern void *head_page(struct trace_array_cpu *data);
 235
 236 #endif /* _LINUX_KERNEL_TRACE_H */