On Mon, Apr 15, 2013 at 7:22 PM, Viresh Kumar viresh.kumar@linaro.org wrote:
On 15 April 2013 21:37, Dirk Brandewie dirk.brandewie@gmail.com wrote:
If the intel_pstate driver is being used __cpufreq_governor() should NOT be called intel_pstate does not implement the target() callback.
Nathan's commit 5800043b2 changed the fence around the call to __cpufreq_governor() in __cpufreq_remove_dev() here is the relevant hunk.
No it isn't.
if (has_target) __cpufreq_governor(data, CPUFREQ_GOV_STOP);As it has taken care of this limitation.
BUT some of my earlier patches haven't. :( Here is the fix (Sedat please try this and give your tested-by, use the attached patch as gmail might break what i am copying in mail)..
Sorry for being late in fixing this issue, i am still down with Tonsil infection and fever.. Today only i got some power to fix it after seeing Dirk's mail.
Your tested-by may help me to recover quickly :)
@Rafael: I will probably be down for one more week and so not doing any reviews for now... I do check important mails sent directly to me though.
Hi Viresh,
can you sent a separate patch on this (with Reported/Tested-by#s)? AFAICS this is not in pm.git#linux-next?
Regards, - Sedat -
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From: Viresh Kumar viresh.kumar@linaro.org Date: Mon, 15 Apr 2013 22:43:57 +0530 Subject: [PATCH] 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 tries to fix this issue.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
drivers/cpufreq/cpufreq.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 3564947..a6f6595 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;