[PATCH 4/5] cpufreq: Remove temporary fix for race between CPUhotplug and sysfs-writes

From: Srivatsa S. Bhat
Date: Fri Sep 06 2013 - 15:58:03 EST


Commit "cpufreq: serialize calls to __cpufreq_governor()" had been a temporary
and partial solution to the race condition between writing to a cpufreq sysfs
file and taking a CPU offline. Now that we have a proper and complete solution
to that problem, remove the temporary fix.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@xxxxxxxxxxxxxxxxxx>
---

drivers/cpufreq/cpufreq.c | 7 +------
include/linux/cpufreq.h | 1 -
2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index c2eb413..9909789 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1783,15 +1783,13 @@ static int __cpufreq_governor(struct cpufreq_policy *policy,
policy->cpu, event);

mutex_lock(&cpufreq_governor_lock);
- if (policy->governor_busy
- || (policy->governor_enabled && event == CPUFREQ_GOV_START)
+ if ((policy->governor_enabled && event == CPUFREQ_GOV_START)
|| (!policy->governor_enabled
&& (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) {
mutex_unlock(&cpufreq_governor_lock);
return -EBUSY;
}

- policy->governor_busy = true;
if (event == CPUFREQ_GOV_STOP)
policy->governor_enabled = false;
else if (event == CPUFREQ_GOV_START)
@@ -1820,9 +1818,6 @@ static int __cpufreq_governor(struct cpufreq_policy *policy,
((event == CPUFREQ_GOV_POLICY_EXIT) && !ret))
module_put(policy->governor->owner);

- mutex_lock(&cpufreq_governor_lock);
- policy->governor_busy = false;
- mutex_unlock(&cpufreq_governor_lock);
return ret;
}

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index cca885d..d568f39 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -76,7 +76,6 @@ struct cpufreq_policy {
struct cpufreq_governor *governor; /* see below */
void *governor_data;
bool governor_enabled; /* governor start/stop flag */
- bool governor_busy;

struct work_struct update; /* if update_policy() needs to be
* called, but you're in IRQ context */

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