kernel/trace/trace_events_stage_3.h

   1 /*
   2  * Stage 3 of the trace events.
   3  *
   4  * Override the macros in <trace/trace_event_types.h> to include the following:
   5  *
   6  * static void ftrace_event_<call>(proto)
   7  * {
   8  *      event_trace_printk(_RET_IP_, "(<call>) " <fmt>);
   9  * }
  10  *
  11  * static int ftrace_reg_event_<call>(void)
  12  * {
  13  *      int ret;
  14  *
  15  *      ret = register_trace_<call>(ftrace_event_<call>);
  16  *      if (!ret)
  17  *              pr_info("event trace: Could not activate trace point "
  18  *                      "probe to  <call>");
  19  *      return ret;
  20  * }
  21  *
  22  * static void ftrace_unreg_event_<call>(void)
  23  * {
  24  *      unregister_trace_<call>(ftrace_event_<call>);
  25  * }
  26  *
  27  * For those macros defined with TRACE_FORMAT:
  28  *
  29  * static struct ftrace_event_call __used
  30  * __attribute__((__aligned__(4)))
  31  * __attribute__((section("_ftrace_events"))) event_<call> = {
  32  *      .name                   = "<call>",
  33  *      .regfunc                = ftrace_reg_event_<call>,
  34  *      .unregfunc              = ftrace_unreg_event_<call>,
  35  * }
  36  *
  37  *
  38  * For those macros defined with TRACE_EVENT_FORMAT:
  39  *
  40  * static struct ftrace_event_call event_<call>;
  41  *
  42  * static void ftrace_raw_event_<call>(proto)
  43  * {
  44  *      struct ring_buffer_event *event;
  45  *      struct ftrace_raw_<call> *entry; <-- defined in stage 1
  46  *      unsigned long irq_flags;
  47  *      int pc;
  48  *
  49  *      local_save_flags(irq_flags);
  50  *      pc = preempt_count();
  51  *
  52  *      event = trace_current_buffer_lock_reserve(event_<call>.id,
  53  *                                sizeof(struct ftrace_raw_<call>),
  54  *                                irq_flags, pc);
  55  *      if (!event)
  56  *              return;
  57  *      entry   = ring_buffer_event_data(event);
  58  *
  59  *      <tstruct>;  <-- Here we assign the entries by the TRACE_FIELD.
  60  *
  61  *      trace_current_buffer_unlock_commit(event, irq_flags, pc);
  62  * }
  63  *
  64  * static int ftrace_raw_reg_event_<call>(void)
  65  * {
  66  *      int ret;
  67  *
  68  *      ret = register_trace_<call>(ftrace_raw_event_<call>);
  69  *      if (!ret)
  70  *              pr_info("event trace: Could not activate trace point "
  71  *                      "probe to <call>");
  72  *      return ret;
  73  * }
  74  *
  75  * static void ftrace_unreg_event_<call>(void)
  76  * {
  77  *      unregister_trace_<call>(ftrace_raw_event_<call>);
  78  * }
  79  *
  80  * static struct trace_event ftrace_event_type_<call> = {
  81  *      .trace                  = ftrace_raw_output_<call>, <-- stage 2
  82  * };
  83  *
  84  * static int ftrace_raw_init_event_<call>(void)
  85  * {
  86  *      int id;
  87  *
  88  *      id = register_ftrace_event(&ftrace_event_type_<call>);
  89  *      if (!id)
  90  *              return -ENODEV;
  91  *      event_<call>.id = id;
  92  *      return 0;
  93  * }
  94  *
  95  * static struct ftrace_event_call __used
  96  * __attribute__((__aligned__(4)))
  97  * __attribute__((section("_ftrace_events"))) event_<call> = {
  98  *      .name                   = "<call>",
  99  *      .regfunc                = ftrace_reg_event_<call>,
 100  *      .unregfunc              = ftrace_unreg_event_<call>,
 101  *      .raw_init               = ftrace_raw_init_event_<call>,
 102  *      .raw_reg                = ftrace_raw_reg_event_<call>,
 103  *      .raw_unreg              = ftrace_raw_unreg_event_<call>,
 104  * }
 105  *
 106  */
 107
 108 #undef TPFMT
 109 #define TPFMT(fmt, args...)     fmt "\n", ##args
 110
 111 #define _TRACE_FORMAT(call, proto, args, fmt)                           \
 112 static void ftrace_event_##call(proto)                                  \
 113 {                                                                       \
 114         event_trace_printk(_RET_IP_, "(" #call ") " fmt);               \
 115 }                                                                       \
 116                                                                         \
 117 static int ftrace_reg_event_##call(void)                                \
 118 {                                                                       \
 119         int ret;                                                        \
 120                                                                         \
 121         ret = register_trace_##call(ftrace_event_##call);               \
 122         if (!ret)                                                       \
 123                 pr_info("event trace: Could not activate trace point "  \
 124                         "probe to " #call);                             \
 125         return ret;                                                     \
 126 }                                                                       \
 127                                                                         \
 128 static void ftrace_unreg_event_##call(void)                             \
 129 {                                                                       \
 130         unregister_trace_##call(ftrace_event_##call);                   \
 131 }                                                                       \
 132
 133
 134 #undef TRACE_FORMAT
 135 #define TRACE_FORMAT(call, proto, args, fmt)                            \
 136 _TRACE_FORMAT(call, PARAMS(proto), PARAMS(args), PARAMS(fmt))           \
 137 static struct ftrace_event_call __used                                  \
 138 __attribute__((__aligned__(4)))                                         \
 139 __attribute__((section("_ftrace_events"))) event_##call = {             \
 140         .name                   = #call,                                \
 141         .system                 = STR(TRACE_SYSTEM),                    \
 142         .regfunc                = ftrace_reg_event_##call,              \
 143         .unregfunc              = ftrace_unreg_event_##call,            \
 144 }
 145
 146 #undef TRACE_FIELD
 147 #define TRACE_FIELD(type, item, assign)\
 148         entry->item = assign;
 149
 150 #undef TRACE_EVENT_FORMAT
 151 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
 152 _TRACE_FORMAT(call, PARAMS(proto), PARAMS(args), PARAMS(fmt))           \
 153                                                                         \
 154 static struct ftrace_event_call event_##call;                           \
 155                                                                         \
 156 static void ftrace_raw_event_##call(proto)                              \
 157 {                                                                       \
 158         struct ring_buffer_event *event;                                \
 159         struct ftrace_raw_##call *entry;                                \
 160         unsigned long irq_flags;                                        \
 161         int pc;                                                         \
 162                                                                         \
 163         local_save_flags(irq_flags);                                    \
 164         pc = preempt_count();                                           \
 165                                                                         \
 166         event = trace_current_buffer_lock_reserve(event_##call.id,      \
 167                                   sizeof(struct ftrace_raw_##call),     \
 168                                   irq_flags, pc);                       \
 169         if (!event)                                                     \
 170                 return;                                                 \
 171         entry   = ring_buffer_event_data(event);                        \
 172                                                                         \
 173         tstruct;                                                        \
 174                                                                         \
 175         trace_current_buffer_unlock_commit(event, irq_flags, pc);       \
 176 }                                                                       \
 177                                                                         \
 178 static int ftrace_raw_reg_event_##call(void)                            \
 179 {                                                                       \
 180         int ret;                                                        \
 181                                                                         \
 182         ret = register_trace_##call(ftrace_raw_event_##call);           \
 183         if (!ret)                                                       \
 184                 pr_info("event trace: Could not activate trace point "  \
 185                         "probe to " #call);                             \
 186         return ret;                                                     \
 187 }                                                                       \
 188                                                                         \
 189 static void ftrace_raw_unreg_event_##call(void)                         \
 190 {                                                                       \
 191         unregister_trace_##call(ftrace_raw_event_##call);               \
 192 }                                                                       \
 193                                                                         \
 194 static struct trace_event ftrace_event_type_##call = {                  \
 195         .trace                  = ftrace_raw_output_##call,             \
 196 };                                                                      \
 197                                                                         \
 198 static int ftrace_raw_init_event_##call(void)                           \
 199 {                                                                       \
 200         int id;                                                         \
 201                                                                         \
 202         id = register_ftrace_event(&ftrace_event_type_##call);          \
 203         if (!id)                                                        \
 204                 return -ENODEV;                                         \
 205         event_##call.id = id;                                           \
 206         return 0;                                                       \
 207 }                                                                       \
 208                                                                         \
 209 static struct ftrace_event_call __used                                  \
 210 __attribute__((__aligned__(4)))                                         \
 211 __attribute__((section("_ftrace_events"))) event_##call = {             \
 212         .name                   = #call,                                \
 213         .system                 = STR(TRACE_SYSTEM),                    \
 214         .regfunc                = ftrace_reg_event_##call,              \
 215         .unregfunc              = ftrace_unreg_event_##call,            \
 216         .raw_init               = ftrace_raw_init_event_##call,         \
 217         .raw_reg                = ftrace_raw_reg_event_##call,          \
 218         .raw_unreg              = ftrace_raw_unreg_event_##call,        \
 219 }