1 files changed, 10 insertions, 14 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 25acf478c9e8..23a63207d747 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -38,7 +38,6 @@ static struct cpufreq_driver   	*cpufreq_driver;
 static struct cpufreq_policy    *cpufreq_cpu_data[NR_CPUS];
 static DEFINE_SPINLOCK(cpufreq_driver_lock);
 
-
 /* internal prototypes */
 static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
 static void handle_update(void *data);
@@ -1115,24 +1114,21 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
         int retval = -EINVAL;
 
         /*
-         * Converted the lock_cpu_hotplug to preempt_disable()
-         * and preempt_enable(). This is a bit kludgy and relies on how cpu
-         * hotplug works. All we need is a guarantee that cpu hotplug won't make
-         * progress on any cpu. Once we do preempt_disable(), this would ensure
-         * that hotplug threads don't get onto this cpu, thereby delaying
-         * the cpu remove process.
-         *
-         * We removed the lock_cpu_hotplug since we need to call this function
-         * via cpu hotplug callbacks, which result in locking the cpu hotplug
-         * thread itself. Agree this is not very clean, cpufreq community
-         * could improve this if required. - Ashok Raj <ashok.raj@intel.com>
+         * If we are already in context of hotplug thread, we dont need to
+         * acquire the hotplug lock. Otherwise acquire cpucontrol to prevent
+         * hotplug from removing this cpu that we are working on.
          */
-        preempt_disable();
+        if (!current_in_cpu_hotplug())
+                lock_cpu_hotplug();
+
         dprintk("target for CPU %u: %u kHz, relation %u\n", policy->cpu,
                 target_freq, relation);
         if (cpu_online(policy->cpu) && cpufreq_driver->target)
                 retval = cpufreq_driver->target(policy, target_freq, relation);
-        preempt_enable();
+
+        if (!current_in_cpu_hotplug())
+                unlock_cpu_hotplug();
+
         return retval;
 }
 EXPORT_SYMBOL_GPL(__cpufreq_driver_target);