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