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 /*
  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         unsigned short          type;
  36         unsigned char           flags;
  37         unsigned char           preempt_count;
  38         int                     pid;
  39         int                     lock_depth;
  40 };
  41
  42 #define FTRACE_MAX_EVENT                                                \
  43         ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
  44
  45 /*
  46  * Trace iterator - used by printout routines who present trace
  47  * results to users and which routines might sleep, etc:
  48  */
  49 struct trace_iterator {
  50         struct trace_array      *tr;
  51         struct tracer           *trace;
  52         void                    *private;
  53         int                     cpu_file;
  54         struct mutex            mutex;
  55         struct ring_buffer_iter *buffer_iter[NR_CPUS];
  56         unsigned long           iter_flags;
  57
  58         /* The below is zeroed out in pipe_read */
  59         struct trace_seq        seq;
  60         struct trace_entry      *ent;
  61         unsigned long           lost_events;
  62         int                     leftover;
  63         int                     cpu;
  64         u64                     ts;
  65
  66         loff_t                  pos;
  67         long                    idx;
  68
  69         cpumask_var_t           started;
  70 };
  71
  72
  73 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
  74                                               int flags);
  75 struct trace_event {
  76         struct hlist_node       node;
  77         struct list_head        list;
  78         int                     type;
  79         trace_print_func        trace;
  80         trace_print_func        raw;
  81         trace_print_func        hex;
  82         trace_print_func        binary;
  83 };
  84
  85 extern int register_ftrace_event(struct trace_event *event);
  86 extern int unregister_ftrace_event(struct trace_event *event);
  87
  88 /* Return values for print_line callback */
  89 enum print_line_t {
  90         TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
  91         TRACE_TYPE_HANDLED      = 1,
  92         TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
  93         TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
  94 };
  95
  96 void tracing_generic_entry_update(struct trace_entry *entry,
  97                                   unsigned long flags,
  98                                   int pc);
  99 struct ring_buffer_event *
 100 trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
 101                                   int type, unsigned long len,
 102                                   unsigned long flags, int pc);
 103 void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 104                                         struct ring_buffer_event *event,
 105                                         unsigned long flags, int pc);
 106 void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
 107                                        struct ring_buffer_event *event,
 108                                         unsigned long flags, int pc);
 109 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 110                                          struct ring_buffer_event *event);
 111
 112 void tracing_record_cmdline(struct task_struct *tsk);
 113
 114 struct event_filter;
 115
 116 enum trace_reg {
 117         TRACE_REG_REGISTER,
 118         TRACE_REG_UNREGISTER,
 119         TRACE_REG_PERF_REGISTER,
 120         TRACE_REG_PERF_UNREGISTER,
 121 };
 122
 123 struct ftrace_event_call;
 124
 125 struct ftrace_event_class {
 126         char                    *system;
 127         void                    *probe;
 128 #ifdef CONFIG_PERF_EVENTS
 129         void                    *perf_probe;
 130 #endif
 131         int                     (*reg)(struct ftrace_event_call *event,
 132                                        enum trace_reg type);
 133 };
 134
 135 struct ftrace_event_call {
 136         struct list_head        list;
 137         struct ftrace_event_class *class;
 138         char                    *name;
 139         struct dentry           *dir;
 140         struct trace_event      *event;
 141         int                     enabled;
 142         int                     id;
 143         const char              *print_fmt;
 144         int                     (*raw_init)(struct ftrace_event_call *);
 145         int                     (*define_fields)(struct ftrace_event_call *);
 146         struct list_head        fields;
 147         int                     filter_active;
 148         struct event_filter     *filter;
 149         void                    *mod;
 150         void                    *data;
 151
 152         int                     perf_refcount;
 153 };
 154
 155 #define PERF_MAX_TRACE_SIZE     2048
 156
 157 #define MAX_FILTER_PRED         32
 158 #define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
 159
 160 extern void destroy_preds(struct ftrace_event_call *call);
 161 extern int filter_match_preds(struct event_filter *filter, void *rec);
 162 extern int filter_current_check_discard(struct ring_buffer *buffer,
 163                                         struct ftrace_event_call *call,
 164                                         void *rec,
 165                                         struct ring_buffer_event *event);
 166
 167 enum {
 168         FILTER_OTHER = 0,
 169         FILTER_STATIC_STRING,
 170         FILTER_DYN_STRING,
 171         FILTER_PTR_STRING,
 172 };
 173
 174 extern int trace_event_raw_init(struct ftrace_event_call *call);
 175 extern int trace_define_field(struct ftrace_event_call *call, const char *type,
 176                               const char *name, int offset, int size,
 177                               int is_signed, int filter_type);
 178 extern int trace_add_event_call(struct ftrace_event_call *call);
 179 extern void trace_remove_event_call(struct ftrace_event_call *call);
 180
 181 #define is_signed_type(type)    (((type)(-1)) < 0)
 182
 183 int trace_set_clr_event(const char *system, const char *event, int set);
 184
 185 /*
 186  * The double __builtin_constant_p is because gcc will give us an error
 187  * if we try to allocate the static variable to fmt if it is not a
 188  * constant. Even with the outer if statement optimizing out.
 189  */
 190 #define event_trace_printk(ip, fmt, args...)                            \
 191 do {                                                                    \
 192         __trace_printk_check_format(fmt, ##args);                       \
 193         tracing_record_cmdline(current);                                \
 194         if (__builtin_constant_p(fmt)) {                                \
 195                 static const char *trace_printk_fmt                     \
 196                   __attribute__((section("__trace_printk_fmt"))) =      \
 197                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 198                                                                         \
 199                 __trace_bprintk(ip, trace_printk_fmt, ##args);          \
 200         } else                                                          \
 201                 __trace_printk(ip, fmt, ##args);                        \
 202 } while (0)
 203
 204 #ifdef CONFIG_PERF_EVENTS
 205 struct perf_event;
 206
 207 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
 208
 209 extern int perf_trace_enable(int event_id);
 210 extern void perf_trace_disable(int event_id);
 211 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
 212                                      char *filter_str);
 213 extern void ftrace_profile_free_filter(struct perf_event *event);
 214 extern void *
 215 perf_trace_buf_prepare(int size, unsigned short type, int *rctxp,
 216                          unsigned long *irq_flags);
 217
 218 static inline void
 219 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
 220                        u64 count, unsigned long irq_flags, struct pt_regs *regs)
 221 {
 222         struct trace_entry *entry = raw_data;
 223
 224         perf_tp_event(entry->type, addr, count, raw_data, size, regs);
 225         perf_swevent_put_recursion_context(rctx);
 226         local_irq_restore(irq_flags);
 227 }
 228 #endif
 229
 230 #endif /* _LINUX_FTRACE_EVENT_H */