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  * Special (free-form) trace entry:
  30  */
  31 struct special_entry {
  32         unsigned long           arg1;
  33         unsigned long           arg2;
  34         unsigned long           arg3;
  35 };
  36
  37 /*
  38  * The trace entry - the most basic unit of tracing. This is what
  39  * is printed in the end as a single line in the trace output, such as:
  40  *
  41  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  42  */
  43 struct trace_entry {
  44         char                    type;
  45         char                    cpu;
  46         char                    flags;
  47         char                    preempt_count;
  48         int                     pid;
  49         cycle_t                 t;
  50         union {
  51                 struct ftrace_entry             fn;
  52                 struct ctx_switch_entry         ctx;
  53                 struct special_entry            special;
  54         };
  55 };
  56
  57 #define TRACE_ENTRY_SIZE        sizeof(struct trace_entry)
  58
  59 /*
  60  * The CPU trace array - it consists of thousands of trace entries
  61  * plus some other descriptor data: (for example which task started
  62  * the trace, etc.)
  63  */
  64 struct trace_array_cpu {
  65         struct list_head        trace_pages;
  66         atomic_t                disabled;
  67         spinlock_t              lock;
  68         struct lock_class_key   lock_key;
  69
  70         /* these fields get copied into max-trace: */
  71         unsigned                trace_head_idx;
  72         unsigned                trace_tail_idx;
  73         void                    *trace_head; /* producer */
  74         void                    *trace_tail; /* consumer */
  75         unsigned long           trace_idx;
  76         unsigned long           saved_latency;
  77         unsigned long           critical_start;
  78         unsigned long           critical_end;
  79         unsigned long           critical_sequence;
  80         unsigned long           nice;
  81         unsigned long           policy;
  82         unsigned long           rt_priority;
  83         cycle_t                 preempt_timestamp;
  84         pid_t                   pid;
  85         uid_t                   uid;
  86         char                    comm[TASK_COMM_LEN];
  87 };
  88
  89 struct trace_iterator;
  90
  91 /*
  92  * The trace array - an array of per-CPU trace arrays. This is the
  93  * highest level data structure that individual tracers deal with.
  94  * They have on/off state as well:
  95  */
  96 struct trace_array {
  97         unsigned long           entries;
  98         long                    ctrl;
  99         int                     cpu;
 100         cycle_t                 time_start;
 101         struct task_struct      *waiter;
 102         struct trace_array_cpu  *data[NR_CPUS];
 103 };
 104
 105 /*
 106  * A specific tracer, represented by methods that operate on a trace array:
 107  */
 108 struct tracer {
 109         const char              *name;
 110         void                    (*init)(struct trace_array *tr);
 111         void                    (*reset)(struct trace_array *tr);
 112         void                    (*open)(struct trace_iterator *iter);
 113         void                    (*close)(struct trace_iterator *iter);
 114         void                    (*start)(struct trace_iterator *iter);
 115         void                    (*stop)(struct trace_iterator *iter);
 116         void                    (*ctrl_update)(struct trace_array *tr);
 117 #ifdef CONFIG_FTRACE_STARTUP_TEST
 118         int                     (*selftest)(struct tracer *trace,
 119                                             struct trace_array *tr);
 120 #endif
 121         struct tracer           *next;
 122         int                     print_max;
 123 };
 124
 125 struct trace_seq {
 126         unsigned char           buffer[PAGE_SIZE];
 127         unsigned int            len;
 128 };
 129
 130 /*
 131  * Trace iterator - used by printout routines who present trace
 132  * results to users and which routines might sleep, etc:
 133  */
 134 struct trace_iterator {
 135         struct trace_seq        seq;
 136         struct trace_array      *tr;
 137         struct tracer           *trace;
 138
 139         struct trace_entry      *ent;
 140         int                     cpu;
 141
 142         struct trace_entry      *prev_ent;
 143         int                     prev_cpu;
 144
 145         unsigned long           iter_flags;
 146         loff_t                  pos;
 147         unsigned long           next_idx[NR_CPUS];
 148         struct list_head        *next_page[NR_CPUS];
 149         unsigned                next_page_idx[NR_CPUS];
 150         long                    idx;
 151 };
 152
 153 void notrace tracing_reset(struct trace_array_cpu *data);
 154 int tracing_open_generic(struct inode *inode, struct file *filp);
 155 struct dentry *tracing_init_dentry(void);
 156 void ftrace(struct trace_array *tr,
 157                             struct trace_array_cpu *data,
 158                             unsigned long ip,
 159                             unsigned long parent_ip,
 160                             unsigned long flags);
 161 void tracing_sched_switch_trace(struct trace_array *tr,
 162                                 struct trace_array_cpu *data,
 163                                 struct task_struct *prev,
 164                                 struct task_struct *next,
 165                                 unsigned long flags);
 166 void tracing_record_cmdline(struct task_struct *tsk);
 167 void trace_special(struct trace_array *tr,
 168                    struct trace_array_cpu *data,
 169                    unsigned long arg1,
 170                    unsigned long arg2,
 171                    unsigned long arg3);
 172 void trace_function(struct trace_array *tr,
 173                     struct trace_array_cpu *data,
 174                     unsigned long ip,
 175                     unsigned long parent_ip,
 176                     unsigned long flags);
 177
 178 void tracing_start_function_trace(void);
 179 void tracing_stop_function_trace(void);
 180 int register_tracer(struct tracer *type);
 181 void unregister_tracer(struct tracer *type);
 182
 183 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 184
 185 extern unsigned long tracing_max_latency;
 186 extern unsigned long tracing_thresh;
 187
 188 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 189 void update_max_tr_single(struct trace_array *tr,
 190                           struct task_struct *tsk, int cpu);
 191
 192 extern notrace cycle_t ftrace_now(int cpu);
 193
 194 #ifdef CONFIG_SCHED_TRACER
 195 extern void notrace
 196 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next);
 197 #else
 198 static inline void
 199 wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
 200 {
 201 }
 202 #endif
 203
 204 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 205 typedef void
 206 (*tracer_switch_func_t)(void *private,
 207                         struct task_struct *prev,
 208                         struct task_struct *next);
 209
 210 struct tracer_switch_ops {
 211         tracer_switch_func_t            func;
 212         void                            *private;
 213         struct tracer_switch_ops        *next;
 214 };
 215
 216 extern int register_tracer_switch(struct tracer_switch_ops *ops);
 217 extern int unregister_tracer_switch(struct tracer_switch_ops *ops);
 218
 219 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
 220
 221 #ifdef CONFIG_DYNAMIC_FTRACE
 222 extern unsigned long ftrace_update_tot_cnt;
 223 #endif
 224
 225 #ifdef CONFIG_FTRACE_STARTUP_TEST
 226 #ifdef CONFIG_FTRACE
 227 extern int trace_selftest_startup_function(struct tracer *trace,
 228                                            struct trace_array *tr);
 229 #endif
 230 #ifdef CONFIG_IRQSOFF_TRACER
 231 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 232                                           struct trace_array *tr);
 233 #endif
 234 #ifdef CONFIG_PREEMPT_TRACER
 235 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 236                                              struct trace_array *tr);
 237 #endif
 238 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
 239 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 240                                                  struct trace_array *tr);
 241 #endif
 242 #ifdef CONFIG_SCHED_TRACER
 243 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 244                                          struct trace_array *tr);
 245 #endif
 246 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 247 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 248                                                struct trace_array *tr);
 249 #endif
 250 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 251
 252 extern void *head_page(struct trace_array_cpu *data);
 253
 254 #endif /* _LINUX_KERNEL_TRACE_H */