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