From: Dave Jones <davej@redhat.com>
Date: Wed, 5 Mar 2008 19:07:34 +0000 (-0500)
Subject: [CPUFREQ] Refactor locking in cpufreq_add_dev
X-Git-Tag: v2.6.26-rc1~697^2~4
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=457091181176643787a547dc04eb3cf5dcd822ce;p=linux-2.6

[CPUFREQ] Refactor locking in cpufreq_add_dev

Simplify this by moving the unlocking out of the error
paths into the exit path.

Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
---

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 0f10ce21d8..be78c07f72 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -799,7 +799,6 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
 	ret = cpufreq_driver->init(policy);
 	if (ret) {
 		dprintk("initialization failed\n");
-		unlock_policy_rwsem_write(cpu);
 		goto err_out;
 	}
 	policy->user_policy.min = policy->cpuinfo.min_freq;
@@ -822,7 +821,7 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
 		/* check for existing affected CPUs.  They may not be aware
 		 * of it due to CPU Hotplug.
 		 */
-		managed_policy = cpufreq_cpu_get(j);
+		managed_policy = cpufreq_cpu_get(j);		// FIXME: Where is this released?  What about error paths?
 		if (unlikely(managed_policy)) {
 
 			/* Set proper policy_cpu */
@@ -841,14 +840,11 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
 			ret = sysfs_create_link(&sys_dev->kobj,
 						&managed_policy->kobj,
 						"cpufreq");
-			if (ret) {
-				unlock_policy_rwsem_write(cpu);
+			if (ret)
 				goto err_out_driver_exit;
-			}
 
 			cpufreq_debug_enable_ratelimit();
 			ret = 0;
-			unlock_policy_rwsem_write(cpu);
 			goto err_out_driver_exit; /* call driver->exit() */
 		}
 	}
@@ -858,33 +854,26 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
 	/* prepare interface data */
 	ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &sys_dev->kobj,
 				   "cpufreq");
-	if (ret) {
-		unlock_policy_rwsem_write(cpu);
+	if (ret)
 		goto err_out_driver_exit;
-	}
+
 	/* set up files for this cpu device */
 	drv_attr = cpufreq_driver->attr;
 	while ((drv_attr) && (*drv_attr)) {
 		ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
-		if (ret) {
-			unlock_policy_rwsem_write(cpu);
+		if (ret)
 			goto err_out_driver_exit;
-		}
 		drv_attr++;
 	}
-	if (cpufreq_driver->get){
+	if (cpufreq_driver->get) {
 		ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
-		if (ret) {
-			unlock_policy_rwsem_write(cpu);
+		if (ret)
 			goto err_out_driver_exit;
-		}
 	}
-	if (cpufreq_driver->target){
+	if (cpufreq_driver->target) {
 		ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
-		if (ret) {
-			unlock_policy_rwsem_write(cpu);
+		if (ret)
 			goto err_out_driver_exit;
-		}
 	}
 
 	spin_lock_irqsave(&cpufreq_driver_lock, flags);
@@ -906,10 +895,8 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
 		cpu_sys_dev = get_cpu_sysdev(j);
 		ret = sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
 					"cpufreq");
-		if (ret) {
-			unlock_policy_rwsem_write(cpu);
+		if (ret)
 			goto err_out_unregister;
-		}
 	}
 
 	policy->governor = NULL; /* to assure that the starting sequence is
@@ -949,6 +936,7 @@ err_out_driver_exit:
 		cpufreq_driver->exit(policy);
 
 err_out:
+	unlock_policy_rwsem_write(cpu);
 	kfree(policy);
 
 nomem_out: