include/linux/ftrace_event.h

   1 #ifndef _LINUX_FTRACE_EVENT_H
   2 #define _LINUX_FTRACE_EVENT_H
   3
   4 #include <linux/ring_buffer.h>
   5 #include <linux/trace_seq.h>
   6 #include <linux/percpu.h>
   7 #include <linux/hardirq.h>
   8 #include <linux/perf_event.h>
   9
  10 struct trace_array;
  11 struct tracer;
  12 struct dentry;
  13
  14 DECLARE_PER_CPU(struct trace_seq, ftrace_event_seq);
  15
  16 struct trace_print_flags {
  17         unsigned long           mask;
  18         const char              *name;
  19 };
  20
  21 const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
  22                                    unsigned long flags,
  23                                    const struct trace_print_flags *flag_array);
  24
  25 const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  26                                      const struct trace_print_flags *symbol_array);
  27
  28 const char *ftrace_print_hex_seq(struct trace_seq *p,
  29                                  const unsigned char *buf, int len);
  30
  31 /*
  32  * The trace entry - the most basic unit of tracing. This is what
  33  * is printed in the end as a single line in the trace output, such as:
  34  *
  35  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  36  */
  37 struct trace_entry {
  38         unsigned short          type;
  39         unsigned char           flags;
  40         unsigned char           preempt_count;
  41         int                     pid;
  42         int                     lock_depth;
  43 };
  44
  45 #define FTRACE_MAX_EVENT                                                \
  46         ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
  47
  48 /*
  49  * Trace iterator - used by printout routines who present trace
  50  * results to users and which routines might sleep, etc:
  51  */
  52 struct trace_iterator {
  53         struct trace_array      *tr;
  54         struct tracer           *trace;
  55         void                    *private;
  56         int                     cpu_file;
  57         struct mutex            mutex;
  58         struct ring_buffer_iter *buffer_iter[NR_CPUS];
  59         unsigned long           iter_flags;
  60
  61         /* The below is zeroed out in pipe_read */
  62         struct trace_seq        seq;
  63         struct trace_entry      *ent;
  64         unsigned long           lost_events;
  65         int                     leftover;
  66         int                     cpu;
  67         u64                     ts;
  68
  69         loff_t                  pos;
  70         long                    idx;
  71
  72         cpumask_var_t           started;
  73 };
  74
  75
  76 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
  77                                               int flags);
  78 struct trace_event {
  79         struct hlist_node       node;
  80         struct list_head        list;
  81         int                     type;
  82         trace_print_func        trace;
  83         trace_print_func        raw;
  84         trace_print_func        hex;
  85         trace_print_func        binary;
  86 };
  87
  88 extern int register_ftrace_event(struct trace_event *event);
  89 extern int unregister_ftrace_event(struct trace_event *event);
  90
  91 /* Return values for print_line callback */
  92 enum print_line_t {
  93         TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
  94         TRACE_TYPE_HANDLED      = 1,
  95         TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
  96         TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
  97 };
  98
  99 void tracing_generic_entry_update(struct trace_entry *entry,
 100                                   unsigned long flags,
 101                                   int pc);
 102 struct ring_buffer_event *
 103 trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
 104                                   int type, unsigned long len,
 105                                   unsigned long flags, int pc);
 106 void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 107                                         struct ring_buffer_event *event,
 108                                         unsigned long flags, int pc);
 109 void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
 110                                        struct ring_buffer_event *event,
 111                                         unsigned long flags, int pc);
 112 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 113                                          struct ring_buffer_event *event);
 114
 115 void tracing_record_cmdline(struct task_struct *tsk);
 116
 117 struct event_filter;
 118
 119 struct ftrace_event_call {
 120         struct list_head        list;
 121         char                    *name;
 122         char                    *system;
 123         struct dentry           *dir;
 124         struct trace_event      *event;
 125         int                     enabled;
 126         int                     (*regfunc)(struct ftrace_event_call *);
 127         void                    (*unregfunc)(struct ftrace_event_call *);
 128         int                     id;
 129         const char              *print_fmt;
 130         int                     (*raw_init)(struct ftrace_event_call *);
 131         int                     (*define_fields)(struct ftrace_event_call *);
 132         struct list_head        fields;
 133         int                     filter_active;
 134         struct event_filter     *filter;
 135         void                    *mod;
 136         void                    *data;
 137
 138         int                     perf_refcount;
 139         int                     (*perf_event_enable)(struct ftrace_event_call *);
 140         void                    (*perf_event_disable)(struct ftrace_event_call *);
 141 };
 142
 143 #define PERF_MAX_TRACE_SIZE     2048
 144
 145 #define MAX_FILTER_PRED         32
 146 #define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
 147
 148 extern void destroy_preds(struct ftrace_event_call *call);
 149 extern int filter_match_preds(struct event_filter *filter, void *rec);
 150 extern int filter_current_check_discard(struct ring_buffer *buffer,
 151                                         struct ftrace_event_call *call,
 152                                         void *rec,
 153                                         struct ring_buffer_event *event);
 154
 155 enum {
 156         FILTER_OTHER = 0,
 157         FILTER_STATIC_STRING,
 158         FILTER_DYN_STRING,
 159         FILTER_PTR_STRING,
 160 };
 161
 162 extern int trace_event_raw_init(struct ftrace_event_call *call);
 163 extern int trace_define_field(struct ftrace_event_call *call, const char *type,
 164                               const char *name, int offset, int size,
 165                               int is_signed, int filter_type);
 166 extern int trace_add_event_call(struct ftrace_event_call *call);
 167 extern void trace_remove_event_call(struct ftrace_event_call *call);
 168
 169 #define is_signed_type(type)    (((type)(-1)) < 0)
 170
 171 int trace_set_clr_event(const char *system, const char *event, int set);
 172
 173 /*
 174  * The double __builtin_constant_p is because gcc will give us an error
 175  * if we try to allocate the static variable to fmt if it is not a
 176  * constant. Even with the outer if statement optimizing out.
 177  */
 178 #define event_trace_printk(ip, fmt, args...)                            \
 179 do {                                                                    \
 180         __trace_printk_check_format(fmt, ##args);                       \
 181         tracing_record_cmdline(current);                                \
 182         if (__builtin_constant_p(fmt)) {                                \
 183                 static const char *trace_printk_fmt                     \
 184                   __attribute__((section("__trace_printk_fmt"))) =      \
 185                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 186                                                                         \
 187                 __trace_bprintk(ip, trace_printk_fmt, ##args);          \
 188         } else                                                          \
 189                 __trace_printk(ip, fmt, ##args);                        \
 190 } while (0)
 191
 192 #ifdef CONFIG_PERF_EVENTS
 193 struct perf_event;
 194
 195 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
 196
 197 extern int perf_trace_enable(int event_id);
 198 extern void perf_trace_disable(int event_id);
 199 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
 200                                      char *filter_str);
 201 extern void ftrace_profile_free_filter(struct perf_event *event);
 202 extern void *
 203 perf_trace_buf_prepare(int size, unsigned short type, int *rctxp,
 204                          unsigned long *irq_flags);
 205
 206 static inline void
 207 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
 208                        u64 count, unsigned long irq_flags, struct pt_regs *regs)
 209 {
 210         struct trace_entry *entry = raw_data;
 211
 212         perf_tp_event(entry->type, addr, count, raw_data, size, regs);
 213         perf_swevent_put_recursion_context(rctx);
 214         local_irq_restore(irq_flags);
 215 }
 216 #endif
 217
 218 #endif /* _LINUX_FTRACE_EVENT_H */