On Mon, Apr 15, 2013 at 7:51 PM, Sedat Dilek sedat.dilek@gmail.com wrote:
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 :)
Hehe. Me myself and I was today chez-mon-docteur... Let's see the results on Thursday. Again, get well soon.
Tested against...
"BROKEN" Linux-Next (next-20130411) with attached patchset (incl. your cpufreq-next-fixes).
Test-Case...
CONFIG_X86_INTEL_PSTATE=y
root# echo 0 > /sys/devices/system/cpu/cpu3/online
Tested-by: Sedat Dilek sedat.dilek@gmail.com
...did not test on-reboot-case.
( Dirk promised to test as well... )
Might be interesting as an extra-confirmation:
root# echo 1 > /sys/devices/system/cpu/cpu3/online
[ dmesg ]
[ 556.101961] smpboot: Booting Node 0 Processor 3 APIC 0x3 [ 556.113158] Disabled fast string operations [ 556.116621] Intel pstate controlling: cpu 3
- Sedat -
- Sedat -
@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.
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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;