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Date: Sat, 20 Mar 2010 16:19:23 +0300
From: Dan Carpenter <error27@gmail.com>
To: Ingo Molnar <mingo@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
       Steven Rostedt <rostedt@goodmis.org>, Li Zefan <lizf@cn.fujitsu.com>,
       Tom Zanussi <tzanussi@gmail.com>, linux-kernel@vger.kernel.org,
       kernel-janitors@vger.kernel.org
Subject: [patch] trace: find the correct ftrace event
Message-ID: <20100320131923.GA20922@bicker>
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	Ingo Molnar <mingo@redhat.com>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Li Zefan <lizf@cn.fujitsu.com>, Tom Zanussi <tzanussi@gmail.com>,
	linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
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The original code doesn't work because "call" is never NULL there.

Signed-off-by: Dan Carpenter <error27@gmail.com>
---
My code should work, but it seems like there should but it seems like
there should be a more elegant way to do this?

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 4615f62..6070c70 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1388,16 +1388,19 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
 	struct event_filter *filter;
 	struct filter_parse_state *ps;
 	struct ftrace_event_call *call = NULL;
+	int found = 0;
 
 	mutex_lock(&event_mutex);
 
 	list_for_each_entry(call, &ftrace_events, list) {
-		if (call->id == event_id)
+		if (call->id == event_id) {
+			found = 1;
 			break;
+		}
 	}
 
 	err = -EINVAL;
-	if (!call)
+	if (!found)
 		goto out_unlock;
 
 	err = -EEXIST;