tracing/perf: Expand TRACE_EVENT(sched_stat_runtime)

To simplify the review of the next patches:

1. We are going to reimplent __perf_task/counter and embedd them
   into TP_ARGS(). expand TRACE_EVENT(sched_stat_runtime) into
   DECLARE_EVENT_CLASS() + DEFINE_EVENT(), this way they can use
   different TP_ARGS's.

2. Change perf_trace_##call() macro to do perf_fetch_caller_regs()
   right before perf_trace_buf_prepare().

   This way it evaluates TP_ARGS() asap, the next patch explores
   this fact.

   Note: after 87f44bbc perf_trace_buf_prepare() doesn't need
   "struct pt_regs *regs", perhaps it makes sense to remove this
   argument. And perhaps we can teach perf_trace_buf_submit()
   to accept regs == NULL and do fetch_caller_regs(CALLER_ADDR1)
   in this case.

3. Cosmetic, but the typecast from "void*" buys nothing. It just
   adds the noise, remove it.

Link: http://lkml.kernel.org/r/20130806160841.GA2736@redhat.com

Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

2 files changed, 8 insertions, 5 deletions

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index e5586caff67a..249c024e67ae 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -372,7 +372,7 @@ DEFINE_EVENT(sched_stat_template, sched_stat_blocked,
  * Tracepoint for accounting runtime (time the task is executing
  * on a CPU).
  */
-TRACE_EVENT(sched_stat_runtime,
+DECLARE_EVENT_CLASS(sched_stat_runtime,
 
         TP_PROTO(struct task_struct *tsk, u64 runtime, u64 vruntime),
 
@@ -401,6 +401,10 @@ TRACE_EVENT(sched_stat_runtime,
                         (unsigned long long)__entry->vruntime)
 );
 
+DEFINE_EVENT(sched_stat_runtime, sched_stat_runtime,
+             TP_PROTO(struct task_struct *tsk, u64 runtime, u64 vruntime),
+             TP_ARGS(tsk, runtime, vruntime));
+
 /*
  * Tracepoint for showing priority inheritance modifying a tasks
  * priority.
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 41a6643e2136..618af05f0be6 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -663,15 +663,14 @@ perf_trace_##call(void *__data, proto)					\
         int __data_size;                                                \
         int rctx;                                                       \
                                                                         \
-        perf_fetch_caller_regs(&__regs);                                \
-                                                                        \
         __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
         __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
                              sizeof(u64));                              \
         __entry_size -= sizeof(u32);                                    \
                                                                         \
-        entry = (struct ftrace_raw_##call *)perf_trace_buf_prepare(     \
-                __entry_size, event_call->event.type, &__regs, &rctx);  \
+        perf_fetch_caller_regs(&__regs);                                \
+        entry = perf_trace_buf_prepare(__entry_size,                    \
+                        event_call->event.type, &__regs, &rctx);        \
         if (!entry)                                                     \
                 return;                                                 \
                                                                         \