[PATCH] oprofile, arm: proper release resources on failure

[Robert Richter <robert.richter@amd.com>]

Will,

the patch below fixes a resource leak I found during code review. Can
you please review and test it (I don't have an ARM environment for
this available). If you are fine with the change, please ack. I want
to send it upstream via tip/perf/urgent.

Though you reworked the code already, parts of the fix are still valid
for latest oprofile code in oprofile/core.

Ingo,

if Will agrees with it, please apply it directly to tip/perf/urgent.

Thanks,

-Robert

--

>From 6cb93a9063c579ec0183406933bfe07e8cc92c34 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Wed, 29 Sep 2010 16:03:11 +0200
Subject: [PATCH] oprofile, arm: proper release resources on failure

This patch fixes a resource leak on failure, where the oprofilefs and
some counters may not released properly.

Fix is also for 2.6.35-stable.

Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@kernel.org
Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 arch/arm/oprofile/common.c |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/arm/oprofile/common.c b/arch/arm/oprofile/common.c
index 0691176..72e09eb 100644
--- a/arch/arm/oprofile/common.c
+++ b/arch/arm/oprofile/common.c
@@ -102,6 +102,7 @@ static int op_create_counter(int cpu, int event)
 	if (IS_ERR(pevent)) {
 		ret = PTR_ERR(pevent);
 	} else if (pevent->state != PERF_EVENT_STATE_ACTIVE) {
+		perf_event_release_kernel(pevent);
 		pr_warning("oprofile: failed to enable event %d "
 				"on CPU %d\n", event, cpu);
 		ret = -EBUSY;
@@ -365,6 +366,7 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
 	ret = init_driverfs();
 	if (ret) {
 		kfree(counter_config);
+		counter_config = NULL;
 		return ret;
 	}
 
@@ -402,7 +404,6 @@ void oprofile_arch_exit(void)
 	struct perf_event *event;
 
 	if (*perf_events) {
-		exit_driverfs();
 		for_each_possible_cpu(cpu) {
 			for (id = 0; id < perf_num_counters; ++id) {
 				event = perf_events[cpu][id];
@@ -413,8 +414,10 @@ void oprofile_arch_exit(void)
 		}
 	}
 
-	if (counter_config)
+	if (counter_config) {
 		kfree(counter_config);
+		exit_driverfs();
+	}
 }
 #else
 int __init oprofile_arch_init(struct oprofile_operations *ops)
-- 
1.7.2.2



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