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| author | Viresh Kumar <viresh.kumar@linaro.org> | 2013-04-22 00:48:03 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-04-22 00:48:03 +0200 |
| commit | 820c6ca293e99ae225dc9dd7e0e689c444b08f92 (patch) | |
| tree | bb4baa6b7e3d27f7495d248ba3e0235470751ac2 /drivers/cpufreq | |
| parent | cpufreq: exynos5440: Protect OPP search calls with RCU lock (diff) | |
| download | linux-820c6ca293e99ae225dc9dd7e0e689c444b08f92.tar.xz linux-820c6ca293e99ae225dc9dd7e0e689c444b08f92.zip | |
cpufreq: Don't call __cpufreq_governor() for drivers without target()
Some cpufreq drivers implement their own governor and so don't need
us to call generic governors interface via __cpufreq_governor(). Few
recent commits haven't obeyed this law well and we saw some
regressions.
This patch is an attempt to fix the above issue.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 3564947ea7ac..a6f65954b0ab 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -858,13 +858,18 @@ static int cpufreq_add_policy_cpu(unsigned int cpu, unsigned int sibling, struct device *dev) { struct cpufreq_policy *policy; - int ret = 0; + int ret = 0, has_target = 0; unsigned long flags; policy = cpufreq_cpu_get(sibling); WARN_ON(!policy); - __cpufreq_governor(policy, CPUFREQ_GOV_STOP); + rcu_read_lock(); + has_target = !!rcu_dereference(cpufreq_driver)->target; + rcu_read_unlock(); + + if (has_target) + __cpufreq_governor(policy, CPUFREQ_GOV_STOP); lock_policy_rwsem_write(sibling); @@ -877,8 +882,10 @@ static int cpufreq_add_policy_cpu(unsigned int cpu, unsigned int sibling, unlock_policy_rwsem_write(sibling); - __cpufreq_governor(policy, CPUFREQ_GOV_START); - __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + if (has_target) { + __cpufreq_governor(policy, CPUFREQ_GOV_START); + __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + } ret = sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); if (ret) { @@ -1146,7 +1153,8 @@ static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif /* If cpu is last user of policy, free policy */ if (cpus == 1) { - __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); + if (has_target) + __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); lock_policy_rwsem_read(cpu); kobj = &data->kobj; |