ftrace: Fix perf-tracepoint OOPS
Not all tracepoints are created equal, in specific the ftrace
tracepoints are created with TRACE_EVENT_FORMAT() which does
not generate the needed bits to tie them into perf counters.
For those events, don't create the 'id' file and fail
->profile_enable when their ID is specified through other
means.
Reported-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1249497664.5890.4.camel@laptop>
[ v2: fix build error in the !CONFIG_EVENT_PROFILE case ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 5c093ff..d7cd193 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -119,11 +119,9 @@
void *filter;
void *mod;
-#ifdef CONFIG_EVENT_PROFILE
- atomic_t profile_count;
- int (*profile_enable)(struct ftrace_event_call *);
- void (*profile_disable)(struct ftrace_event_call *);
-#endif
+ atomic_t profile_count;
+ int (*profile_enable)(struct ftrace_event_call *);
+ void (*profile_disable)(struct ftrace_event_call *);
};
#define MAX_FILTER_PRED 32
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 5b5895a..11ba5bb 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -14,7 +14,7 @@
mutex_lock(&event_mutex);
list_for_each_entry(event, &ftrace_events, list) {
- if (event->id == event_id) {
+ if (event->id == event_id && event->profile_enable) {
ret = event->profile_enable(event);
break;
}
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 23d2972..e75276a 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -940,7 +940,7 @@
entry = trace_create_file("enable", 0644, call->dir, call,
enable);
- if (call->id)
+ if (call->id && call->profile_enable)
entry = trace_create_file("id", 0444, call->dir, call,
id);
