On 04/15/2013 10:27 AM, Nathan Zimmer wrote:
On 04/15/2013 11:07 AM, Dirk Brandewie wrote:
On 04/13/2013 02:55 AM, Sedat Dilek wrote:
On Sat, Apr 13, 2013 at 12:51 AM, Rafael J. Wysocki rjw@sisk.pl wrote:
On Friday, April 12, 2013 11:08:37 PM Sedat Dilek wrote:
On Fri, Apr 12, 2013 at 6:27 PM, Sedat Dilek sedat.dilek@gmail.com wrote:
On Fri, Apr 12, 2013 at 5:45 PM, Sedat Dilek sedat.dilek@gmail.com wrote: > On Fri, Apr 12, 2013 at 4:24 PM, Sedat Dilek sedat.dilek@gmail.com wrote: >> On Fri, Apr 12, 2013 at 10:23 AM, Viresh Kumar viresh.kumar@linaro.org >> wrote: >>> On 10 April 2013 11:44, Sedat Dilek sedat.dilek@gmail.com wrote: >>>> I found this "[RFC PATCH] kbuild: Build linux-tools package with 'make >>>> deb-pkg'" from February 2012. >>>> Can't say what happened to it... >>> >>> Sedat, >>> >>> Sorry for being late. I am down with Fever and throat infection since >>> few days. >>> Still struggling with it.. >>> >>> There are few things i tried. Firstly the tag: next-20130326 is bad as >>> there are >>> some bad commits in cpufreq core in it. >>> >>> I then tried latest linux-next/master on my Thinkpad (model name >>> : Intel(R) >>> Core(TM) i7-2640M CPU @ 2.80GHz) and couldn't boot it up. My ubuntu >>> just hanged. >>> >>> Then i tried Rafael's linux-next branch >>> >>> 079576f Merge branch 'pm-cpufreq-next' into linux-next >>> >>> And couldn't find any issues with it. I am easily able to remove/add >>> cpus at >>> runtime.. >>> >>> Can you give this branch a try? >>> >> >> OK, you seem to be well again, nice to hear. >> >> I was doing the whole week spring-cleaning in the apartment of my parents. >> Now, I have some minutes for a compilation run. >> >> I guess "cpufreq: Call __cpufreq_governor() with correct policy->cpus >> mask" could be the correct fix, but will try the GIT branch you have >> mentioned. >> >> - Sedat - >> >> [1] >> http://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/commit/?h=li... >> >> > > Both BROKEN here, specific pm-next commitid and pulling > pm.git#linux-next into next-20130411 (see attached files). > > Is "cpufreq: convert cpufreq_driver to using RCU" the root cause of this > all? >
[ CC Nathan ]
NO, wrong assumption.
2013-04-12 18:04 Sedat Dilek o [revert-cpufreq-rcu] Revert "cpufreq: convert cpufreq_driver to using RCU" 2013-04-12 18:04 Sedat Dilek o Revert "cpufreq: Call __cpufreq_governor() with correct policy->cpus mask" 2013-04-11 23:24 Rafael J. Wysocki M─┐ [pm-next-079576f] Merge branch 'pm-cpufreq-next' into linux-next
- Sedat -
> - Sedat - > > [1] > http://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/commit/?h=li... > > >>> -- >>> viresh
[ TO Dirk (Author of Intel pstate driver) ]
With CONFIG_X86_INTEL_PSTATE=n (unset) I do not see the call-trace!
My kernel-config and dmesg are attached.
You're seeing a trouble with a new driver, then, so that's not a regression.
This IS a regression.
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.
@@ -1007,9 +1068,12 @@ static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif unsigned int cpu = dev->id, ret, cpus; unsigned long flags; struct cpufreq_policy *data;
struct cpufreq_driver *driver; struct kobject *kobj; struct completion *cmp; struct device *cpu_dev;
bool has_target;
int (*exit)(struct cpufreq_policy *policy);
pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
@@ -1025,14 +1089,19 @@ static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif return -EINVAL; }
- if (cpufreq_driver->target)
- rcu_read_lock();
- driver = rcu_dereference(cpufreq_driver);
- has_target = driver->target ? true : false;
- exit = driver->exit;
- if (has_target) __cpufreq_governor(data, CPUFREQ_GOV_STOP);
#ifdef CONFIG_HOTPLUG_CPU
- if (!cpufreq_driver->setpolicy)
- if (!driver->setpolicy) strncpy(per_cpu(cpufreq_cpu_governor, cpu), data->governor->name, CPUFREQ_NAME_LEN);
#endif
rcu_read_unlock();
WARN_ON(lock_policy_rwsem_write(cpu)); cpus = cpumask_weight(data->cpus);
I am not clear at what is at issue. Are you saying __cpufreq_governor can change the value of cpufreq_driver->target? I hadn't thought that was allowed but if it is the code would need to be fixed.
Sorry I think pointing to your patch may have red herring see viresh's mail.
The issue is that __cpufreq_governor() is being called when intel_pstate is the scaling driver intel_pstate does not implement ->target(). From the stack trace it looked like this was happening in __cpufreq_remove_dev() so I "assumed" it was the first instance of the target fence that was failing.
I am rebuilding using the next tree with viresh's patch I will let you know what I find sorry for the noise.
--Dirk
Nate