This broke after a recent change "cedb70a cpufreq: Split __cpufreq_remove_dev()
into two parts" from Srivatsa..
Consider a scenario where we have two CPUs in a policy (0 & 1) and we are
removing cpu 1. On the call to __cpufreq_remove_dev_prepare() we have cleared 1
from policy->cpus and now on a call to __cpufreq_remove_dev_finish() we read
cpumask_weight of policy->cpus, which will come as 1 and this code will behave
as if we are removing the last cpu from policy :)
Fix it by clearing cpu mask in __cpufreq_remove_dev_finish() instead of
__cpufreq_remove_dev_prepare().
Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
drivers/cpufreq/cpufreq.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 0e11fcb..b556d46 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1175,12 +1175,9 @@ static int __cpufreq_remove_dev_prepare(struct device
*dev,
policy->governor->name, CPUFREQ_NAME_LEN);
#endif
- WARN_ON(lock_policy_rwsem_write(cpu));
+ lock_policy_rwsem_read(cpu);
cpus = cpumask_weight(policy->cpus);
-
- if (cpus > 1)
- cpumask_clear_cpu(cpu, policy->cpus);
- unlock_policy_rwsem_write(cpu);
+ unlock_policy_rwsem_read(cpu);
if (cpu != policy->cpu) {
if (!frozen)
@@ -1222,9 +1219,12 @@ static int __cpufreq_remove_dev_finish(struct device
*dev,
return -EINVAL;
}
- lock_policy_rwsem_read(cpu);
+ WARN_ON(lock_policy_rwsem_write(cpu));
cpus = cpumask_weight(policy->cpus);
- unlock_policy_rwsem_read(cpu);
+
+ if (cpus > 1)
+ cpumask_clear_cpu(cpu, policy->cpus);
+ unlock_policy_rwsem_write(cpu);
/* If cpu is last user of policy, free policy */
if (cpus == 1) {
--
1.7.12.rc2.18.g61b472e
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