[PATCH 01/13] cpufreq: acpi: call CPUFREQ_POSTCHANGE notfier in error cases

From: Viresh Kumar <viresh.kumar@linaro.org>
To: rjw@sisk.pl
Cc: linaro-kernel@lists.linaro.org, patches@linaro.org,
	cpufreq@vger.kernel.org, linux-pm@vger.kernel.org,
	linux-kernel@vger.kernel.org, robin.randhawa@arm.com,
	Steve.Bannister@arm.com, Liviu.Dudau@arm.com,
	charles.garcia-tobin@arm.com, arvind.chauhan@arm.com,
	dave.martin@arm.com, Viresh Kumar <viresh.kumar@linaro.org>,
	Borislav Petkov <bp@suse.de>
Subject: [PATCH 01/13] cpufreq: acpi: call CPUFREQ_POSTCHANGE notfier in error cases
Date: Wed, 19 Jun 2013 14:22:55 +0530	[thread overview]
Message-ID: <27d5d1fbc05f7cd41a566ca430cbd432804a5acd.1371630975.git.viresh.kumar@linaro.org> (raw)
In-Reply-To: <cover.1371630975.git.viresh.kumar@linaro.org>
In-Reply-To: <cover.1371630975.git.viresh.kumar@linaro.org>

PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both
should be called or both shouldn't be.

In case we have started PRECHANGE notifier and found an error, we must call
POSTCHANGE notifier with freqs.new = freqs.old to guarantee that sequence of
calling notifiers is complete.

This patch fixes it.

Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/cpufreq/acpi-cpufreq.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index edc089e..223ddf4 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -494,12 +494,14 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 			pr_debug("acpi_cpufreq_target failed (%d)\n",
 				policy->cpu);
 			result = -EAGAIN;
-			goto out;
+			freqs.new = freqs.old;
 		}
 	}
 
 	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-	perf->state = next_perf_state;
+
+	if (!result)
+		perf->state = next_perf_state;
 
 out:
 	return result;
-- 
1.7.12.rc2.18.g61b472e

