LXR linux/include/linux/ftrace

   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
  10struct trace_array;
  11struct tracer;
  12struct dentry;
  13
  14struct trace_print_flags {
  15        unsigned long           mask;
  16        const char              *name;
  17};
  18
  19struct trace_print_flags_u64 {
  20        unsigned long long      mask;
  21        const char              *name;
  22};
  23
  24const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
  25                                   unsigned long flags,
  26                                   const struct trace_print_flags *flag_array);
  27
  28const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  29                                     const struct trace_print_flags *symbol_array);
  30
  31#if BITS_PER_LONG == 32
  32const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
  33                                         unsigned long long val,
  34                                         const struct trace_print_flags_u64
  35                                                                 *symbol_array);
  36#endif
  37
  38const char *ftrace_print_hex_seq(struct trace_seq *p,
  39                                 const unsigned char *buf, int len);
  40
  41/*
  42 * The trace entry - the most basic unit of tracing. This is what
  43 * is printed in the end as a single line in the trace output, such as:
  44 *
  45 *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  46 */
  47struct trace_entry {
  48        unsigned short          type;
  49        unsigned char           flags;
  50        unsigned char           preempt_count;
  51        int                     pid;
  52        int                     padding;
  53};
  54
  55#define FTRACE_MAX_EVENT                                                \
  56        ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
  57
  58/*
  59 * Trace iterator - used by printout routines who present trace
  60 * results to users and which routines might sleep, etc:
  61 */
  62struct trace_iterator {
  63        struct trace_array      *tr;
  64        struct tracer           *trace;
  65        void                    *private;
  66        int                     cpu_file;
  67        struct mutex            mutex;
  68        struct ring_buffer_iter *buffer_iter[NR_CPUS];
  69        unsigned long           iter_flags;
  70
  71        /* trace_seq for __print_flags() and __print_symbolic() etc. */
  72        struct trace_seq        tmp_seq;
  73
  74        /* The below is zeroed out in pipe_read */
  75        struct trace_seq        seq;
  76        struct trace_entry      *ent;
  77        unsigned long           lost_events;
  78        int                     leftover;
  79        int                     ent_size;
  80        int                     cpu;
  81        u64                     ts;
  82
  83        loff_t                  pos;
  84        long                    idx;
  85
  86        cpumask_var_t           started;
  87};
  88
  89
  90struct trace_event;
  91
  92typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
  93                                      int flags, struct trace_event *event);
  94
  95struct trace_event_functions {
  96        trace_print_func        trace;
  97        trace_print_func        raw;
  98        trace_print_func        hex;
  99        trace_print_func        binary;
 100};
 101
 102struct trace_event {
 103        struct hlist_node               node;
 104        struct list_head                list;
 105        int                             type;
 106        struct trace_event_functions    *funcs;
 107};
 108
 109extern int register_ftrace_event(struct trace_event *event);
 110extern int unregister_ftrace_event(struct trace_event *event);
 111
 112/* Return values for print_line callback */
 113enum print_line_t {
 114        TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
 115        TRACE_TYPE_HANDLED      = 1,
 116        TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
 117        TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
 118};
 119
 120void tracing_generic_entry_update(struct trace_entry *entry,
 121                                  unsigned long flags,
 122                                  int pc);
 123struct ring_buffer_event *
 124trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
 125                                  int type, unsigned long len,
 126                                  unsigned long flags, int pc);
 127void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 128                                        struct ring_buffer_event *event,
 129                                        unsigned long flags, int pc);
 130void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
 131                                       struct ring_buffer_event *event,
 132                                        unsigned long flags, int pc);
 133void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer,
 134                                            struct ring_buffer_event *event,
 135                                            unsigned long flags, int pc,
 136                                            struct pt_regs *regs);
 137void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 138                                         struct ring_buffer_event *event);
 139
 140void tracing_record_cmdline(struct task_struct *tsk);
 141
 142struct event_filter;
 143
 144enum trace_reg {
 145        TRACE_REG_REGISTER,
 146        TRACE_REG_UNREGISTER,
 147        TRACE_REG_PERF_REGISTER,
 148        TRACE_REG_PERF_UNREGISTER,
 149};
 150
 151struct ftrace_event_call;
 152
 153struct ftrace_event_class {
 154        char                    *system;
 155        void                    *probe;
 156#ifdef CONFIG_PERF_EVENTS
 157        void                    *perf_probe;
 158#endif
 159        int                     (*reg)(struct ftrace_event_call *event,
 160                                       enum trace_reg type);
 161        int                     (*define_fields)(struct ftrace_event_call *);
 162        struct list_head        *(*get_fields)(struct ftrace_event_call *);
 163        struct list_head        fields;
 164        int                     (*raw_init)(struct ftrace_event_call *);
 165};
 166
 167extern int ftrace_event_reg(struct ftrace_event_call *event,
 168                            enum trace_reg type);
 169
 170enum {
 171        TRACE_EVENT_FL_ENABLED_BIT,
 172        TRACE_EVENT_FL_FILTERED_BIT,
 173        TRACE_EVENT_FL_RECORDED_CMD_BIT,
 174        TRACE_EVENT_FL_CAP_ANY_BIT,
 175        TRACE_EVENT_FL_NO_SET_FILTER_BIT,
 176};
 177
 178enum {
 179        TRACE_EVENT_FL_ENABLED          = (1 << TRACE_EVENT_FL_ENABLED_BIT),
 180        TRACE_EVENT_FL_FILTERED         = (1 << TRACE_EVENT_FL_FILTERED_BIT),
 181        TRACE_EVENT_FL_RECORDED_CMD     = (1 << TRACE_EVENT_FL_RECORDED_CMD_BIT),
 182        TRACE_EVENT_FL_CAP_ANY          = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
 183        TRACE_EVENT_FL_NO_SET_FILTER    = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
 184};
 185
 186struct ftrace_event_call {
 187        struct list_head        list;
 188        struct ftrace_event_class *class;
 189        char                    *name;
 190        struct dentry           *dir;
 191        struct trace_event      event;
 192        const char              *print_fmt;
 193        struct event_filter     *filter;
 194        void                    *mod;
 195        void                    *data;
 196
 197        /*
 198         * 32 bit flags:
 199         *   bit 1:             enabled
 200         *   bit 2:             filter_active
 201         *   bit 3:             enabled cmd record
 202         *
 203         * Changes to flags must hold the event_mutex.
 204         *
 205         * Note: Reads of flags do not hold the event_mutex since
 206         * they occur in critical sections. But the way flags
 207         * is currently used, these changes do no affect the code
 208         * except that when a change is made, it may have a slight
 209         * delay in propagating the changes to other CPUs due to
 210         * caching and such.
 211         */
 212        unsigned int            flags;
 213
 214#ifdef CONFIG_PERF_EVENTS
 215        int                             perf_refcount;
 216        struct hlist_head __percpu      *perf_events;
 217#endif
 218};
 219
 220#define __TRACE_EVENT_FLAGS(name, value)                                \
 221        static int __init trace_init_flags_##name(void)                 \
 222        {                                                               \
 223                event_##name.flags = value;                             \
 224                return 0;                                               \
 225        }                                                               \
 226        early_initcall(trace_init_flags_##name);
 227
 228#define PERF_MAX_TRACE_SIZE     2048
 229
 230#define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
 231
 232extern void destroy_preds(struct ftrace_event_call *call);
 233extern int filter_match_preds(struct event_filter *filter, void *rec);
 234extern int filter_current_check_discard(struct ring_buffer *buffer,
 235                                        struct ftrace_event_call *call,
 236                                        void *rec,
 237                                        struct ring_buffer_event *event);
 238
 239enum {
 240        FILTER_OTHER = 0,
 241        FILTER_STATIC_STRING,
 242        FILTER_DYN_STRING,
 243        FILTER_PTR_STRING,
 244};
 245
 246#define EVENT_STORAGE_SIZE 128
 247extern struct mutex event_storage_mutex;
 248extern char event_storage[EVENT_STORAGE_SIZE];
 249
 250extern int trace_event_raw_init(struct ftrace_event_call *call);
 251extern int trace_define_field(struct ftrace_event_call *call, const char *type,
 252                              const char *name, int offset, int size,
 253                              int is_signed, int filter_type);
 254extern int trace_add_event_call(struct ftrace_event_call *call);
 255extern void trace_remove_event_call(struct ftrace_event_call *call);
 256
 257#define is_signed_type(type)    (((type)(-1)) < 0)
 258
 259int trace_set_clr_event(const char *system, const char *event, int set);
 260
 261/*
 262 * The double __builtin_constant_p is because gcc will give us an error
 263 * if we try to allocate the static variable to fmt if it is not a
 264 * constant. Even with the outer if statement optimizing out.
 265 */
 266#define event_trace_printk(ip, fmt, args...)                            \
 267do {                                                                    \
 268        __trace_printk_check_format(fmt, ##args);                       \
 269        tracing_record_cmdline(current);                                \
 270        if (__builtin_constant_p(fmt)) {                                \
 271                static const char *trace_printk_fmt                     \
 272                  __attribute__((section("__trace_printk_fmt"))) =      \
 273                        __builtin_constant_p(fmt) ? fmt : NULL;         \
 274                                                                        \
 275                __trace_bprintk(ip, trace_printk_fmt, ##args);          \
 276        } else                                                          \
 277                __trace_printk(ip, fmt, ##args);                        \
 278} while (0)
 279
 280#ifdef CONFIG_PERF_EVENTS
 281struct perf_event;
 282
 283DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
 284
 285extern int  perf_trace_init(struct perf_event *event);
 286extern void perf_trace_destroy(struct perf_event *event);
 287extern int  perf_trace_add(struct perf_event *event, int flags);
 288extern void perf_trace_del(struct perf_event *event, int flags);
 289extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
 290                                     char *filter_str);
 291extern void ftrace_profile_free_filter(struct perf_event *event);
 292extern void *perf_trace_buf_prepare(int size, unsigned short type,
 293                                    struct pt_regs *regs, int *rctxp);
 294
 295static inline void
 296perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
 297                       u64 count, struct pt_regs *regs, void *head)
 298{
 299        perf_tp_event(addr, count, raw_data, size, regs, head, rctx);
 300}
 301#endif
 302
 303#endif /* _LINUX_FTRACE_EVENT_H */
 304