[GIT PULL v3] tracing: A couple of minor fixes

[Steven Rostedt]

Linus,

[ Hopefully the change log of the last commit is good enough ]

Two minor fixes:

 - A race in perf trace initialization (missing mutexes)

 - Minor fix to represent gfp_t in synthetic events as properly signed


Please pull the latest trace-v5.4-rc3-3 tree, which can be found at:


  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
trace-v5.4-rc3-3

Tag SHA1: abdeb1c7a64b38c5259c46978c103afe7d5b000c
Head SHA1: 6b1340cc00edeadd52ebd8a45171f38c8de2a387


Prateek Sood (1):
      tracing: Fix race in perf_trace_buf initialization

Zhengjun Xing (1):
      tracing: Fix "gfp_t" format for synthetic events

----
 kernel/trace/trace_event_perf.c  | 4 ++++
 kernel/trace/trace_events_hist.c | 2 ++
 2 files changed, 6 insertions(+)
---------------------------
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 0892e38ed6fb..a9dfa04ffa44 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -272,9 +272,11 @@ int perf_kprobe_init(struct perf_event *p_event, bool is_retprobe)
 		goto out;
 	}
 
+	mutex_lock(&event_mutex);
 	ret = perf_trace_event_init(tp_event, p_event);
 	if (ret)
 		destroy_local_trace_kprobe(tp_event);
+	mutex_unlock(&event_mutex);
 out:
 	kfree(func);
 	return ret;
@@ -282,8 +284,10 @@ int perf_kprobe_init(struct perf_event *p_event, bool is_retprobe)
 
 void perf_kprobe_destroy(struct perf_event *p_event)
 {
+	mutex_lock(&event_mutex);
 	perf_trace_event_close(p_event);
 	perf_trace_event_unreg(p_event);
+	mutex_unlock(&event_mutex);
 
 	destroy_local_trace_kprobe(p_event->tp_event);
 }
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 57648c5aa679..7482a1466ebf 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -679,6 +679,8 @@ static bool synth_field_signed(char *type)
 {
 	if (str_has_prefix(type, "u"))
 		return false;
+	if (strcmp(type, "gfp_t") == 0)
+		return false;
 
 	return true;
 }