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         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 */