[PATCH] drivers/cpufreq: Add calls to cpufreq_cpu_put

[PATCH] drivers/cpufreq: Add calls to cpufreq_cpu_put

[Julia Lawall]

From: Julia Lawall <julia@diku.dk>

A call to cpufreq_cpu_get should be matched by a call to cpufreq_cpu_put.


The problem was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
identifier E;
expression E1, E2;
int ret;
statement S;
@@

  T E;
  ... when any
(
  E = cpufreq_cpu_get(...);
  if (E == NULL) S
|
  if ((E = cpufreq_cpu_get(...)) == NULL) S
)
  ... when != E2 = E
      when strict
(
  cpufreq_cpu_put(E);
|
  E1 = E;
|
+ cpufreq_cpu_put(E);
  return;
|
+ cpufreq_cpu_put(E);
  return ret;
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
---

diff -u -p a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
--- a/drivers/cpufreq/cpufreq.c 2008-01-06 11:51:40.000000000 +0100
+++ b/drivers/cpufreq/cpufreq.c 2008-01-06 12:01:47.000000000 +0100
@@ -649,8 +649,10 @@ static ssize_t show(struct kobject * kob
 	if (!policy)
 		return -EINVAL;
 
-	if (lock_policy_rwsem_read(policy->cpu) < 0)
+	if (lock_policy_rwsem_read(policy->cpu) < 0) {
+		cpufreq_cpu_put(policy);
 		return -EINVAL;
+	}
 
 	if (fattr->show)
 		ret = fattr->show(policy, buf);
@@ -673,8 +675,10 @@ static ssize_t store(struct kobject * ko
 	if (!policy)
 		return -EINVAL;
 
-	if (lock_policy_rwsem_write(policy->cpu) < 0)
+	if (lock_policy_rwsem_write(policy->cpu) < 0) {
+		cpufreq_cpu_put(policy);
 		return -EINVAL;
+	}
 
 	if (fattr->store)
 		ret = fattr->store(policy, buf, count);