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
  14DECLARE_PER_CPU(struct trace_seq, ftrace_event_seq);
  15
  16struct trace_print_flags {
  17        unsigned long           mask;
  18        const char              *name;
  19};
  20
  21const 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
  25const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  26                                     const struct trace_print_flags *symbol_array);
  27
  28const 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 */
  37struct 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 */
  52struct 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
  76struct trace_event;
  77
  78typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
  79                                      int flags, struct trace_event *event);
  80
  81struct trace_event_functions {
  82        trace_print_func        trace;
  83        trace_print_func        raw;
  84        trace_print_func        hex;
  85        trace_print_func        binary;
  86};
  87
  88struct trace_event {
  89        struct hlist_node               node;
  90        struct list_head                list;
  91        int                             type;
  92        struct trace_event_functions    *funcs;
  93};
  94
  95extern int register_ftrace_event(struct trace_event *event);
  96extern int unregister_ftrace_event(struct trace_event *event);
  97
  98/* Return values for print_line callback */
  99enum print_line_t {
 100        TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
 101        TRACE_TYPE_HANDLED      = 1,
 102        TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
 103        TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
 104};
 105
 106void tracing_generic_entry_update(struct trace_entry *entry,
 107                                  unsigned long flags,
 108                                  int pc);
 109struct ring_buffer_event *
 110trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
 111                                  int type, unsigned long len,
 112                                  unsigned long flags, int pc);
 113void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 114                                        struct ring_buffer_event *event,
 115                                        unsigned long flags, int pc);
 116void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
 117                                       struct ring_buffer_event *event,
 118                                        unsigned long flags, int pc);
 119void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 120                                         struct ring_buffer_event *event);
 121
 122void tracing_record_cmdline(struct task_struct *tsk);
 123
 124struct event_filter;
 125
 126enum trace_reg {
 127        TRACE_REG_REGISTER,
 128        TRACE_REG_UNREGISTER,
 129        TRACE_REG_PERF_REGISTER,
 130        TRACE_REG_PERF_UNREGISTER,
 131};
 132
 133struct ftrace_event_call;
 134
 135struct ftrace_event_class {
 136        char                    *system;
 137        void                    *probe;
 138#ifdef CONFIG_PERF_EVENTS
 139        void                    *perf_probe;
 140#endif
 141        int                     (*reg)(struct ftrace_event_call *event,
 142                                       enum trace_reg type);
 143        int                     (*define_fields)(struct ftrace_event_call *);
 144        struct list_head        *(*get_fields)(struct ftrace_event_call *);
 145        struct list_head        fields;
 146        int                     (*raw_init)(struct ftrace_event_call *);
 147};
 148
 149enum {
 150        TRACE_EVENT_FL_ENABLED_BIT,
 151        TRACE_EVENT_FL_FILTERED_BIT,
 152};
 153
 154enum {
 155        TRACE_EVENT_FL_ENABLED  = (1 << TRACE_EVENT_FL_ENABLED_BIT),
 156        TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
 157};
 158
 159struct ftrace_event_call {
 160        struct list_head        list;
 161        struct ftrace_event_class *class;
 162        char                    *name;
 163        struct dentry           *dir;
 164        struct trace_event      event;
 165        const char              *print_fmt;
 166        struct event_filter     *filter;
 167        void                    *mod;
 168        void                    *data;
 169
 170        /*
 171         * 32 bit flags:
 172         *   bit 1:             enabled
 173         *   bit 2:             filter_active
 174         *
 175         * Changes to flags must hold the event_mutex.
 176         *
 177         * Note: Reads of flags do not hold the event_mutex since
 178         * they occur in critical sections. But the way flags
 179         * is currently used, these changes do no affect the code
 180         * except that when a change is made, it may have a slight
 181         * delay in propagating the changes to other CPUs due to
 182         * caching and such.
 183         */
 184        unsigned int            flags;
 185
 186#ifdef CONFIG_PERF_EVENTS
 187        int                     perf_refcount;
 188        struct hlist_head       *perf_events;
 189#endif
 190};
 191
 192#define PERF_MAX_TRACE_SIZE     2048
 193
 194#define MAX_FILTER_PRED         32
 195#define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
 196
 197extern void destroy_preds(struct ftrace_event_call *call);
 198extern int filter_match_preds(struct event_filter *filter, void *rec);
 199extern int filter_current_check_discard(struct ring_buffer *buffer,
 200                                        struct ftrace_event_call *call,
 201                                        void *rec,
 202                                        struct ring_buffer_event *event);
 203
 204enum {
 205        FILTER_OTHER = 0,
 206        FILTER_STATIC_STRING,
 207        FILTER_DYN_STRING,
 208        FILTER_PTR_STRING,
 209};
 210
 211extern int trace_event_raw_init(struct ftrace_event_call *call);
 212extern int trace_define_field(struct ftrace_event_call *call, const char *type,
 213                              const char *name, int offset, int size,
 214                              int is_signed, int filter_type);
 215extern int trace_add_event_call(struct ftrace_event_call *call);
 216extern void trace_remove_event_call(struct ftrace_event_call *call);
 217
 218#define is_signed_type(type)    (((type)(-1)) < 0)
 219
 220int trace_set_clr_event(const char *system, const char *event, int set);
 221
 222/*
 223 * The double __builtin_constant_p is because gcc will give us an error
 224 * if we try to allocate the static variable to fmt if it is not a
 225 * constant. Even with the outer if statement optimizing out.
 226 */
 227#define event_trace_printk(ip, fmt, args...)                            \
 228do {                                                                    \
 229        __trace_printk_check_format(fmt, ##args);                       \
 230        tracing_record_cmdline(current);                                \
 231        if (__builtin_constant_p(fmt)) {                                \
 232                static const char *trace_printk_fmt                     \
 233                  __attribute__((section("__trace_printk_fmt"))) =      \
 234                        __builtin_constant_p(fmt) ? fmt : NULL;         \
 235                                                                        \
 236                __trace_bprintk(ip, trace_printk_fmt, ##args);          \
 237        } else                                                          \
 238                __trace_printk(ip, fmt, ##args);                        \
 239} while (0)
 240
 241#ifdef CONFIG_PERF_EVENTS
 242struct perf_event;
 243
 244DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
 245
 246extern int  perf_trace_init(struct perf_event *event);
 247extern void perf_trace_destroy(struct perf_event *event);
 248extern int  perf_trace_enable(struct perf_event *event);
 249extern void perf_trace_disable(struct perf_event *event);
 250extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
 251                                     char *filter_str);
 252extern void ftrace_profile_free_filter(struct perf_event *event);
 253extern void *perf_trace_buf_prepare(int size, unsigned short type,
 254                                    struct pt_regs *regs, int *rctxp);
 255
 256static inline void
 257perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
 258                       u64 count, struct pt_regs *regs, void *head)
 259{
 260        perf_tp_event(addr, count, raw_data, size, regs, head);
 261        perf_swevent_put_recursion_context(rctx);
 262}
 263#endif
 264
 265#endif /* _LINUX_FTRACE_EVENT_H */
 266