| Message ID | 1453447145-17722-2-git-send-email-shilpa.bhat@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 22-01-16, 12:49, Shilpasri G Bhat wrote: > In the kworker_thread powernv_cpufreq_work_fn(), we can end up > sending an IPI to a cpu going offline. This is a rare corner case > which is fixed using {get/put}_online_cpus(). Along with this fix, > this patch adds changes to do oneshot cpumask_{clear/and} operation. > > Suggested-by: Shreyas B Prabhu <shreyas@linux.vnet.ibm.com> > Suggested-by: Gautham R Shenoy <ego@linux.vnet.ibm.com> > Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> > Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> > --- > Changes form v5: > - Fix the kbuild-error: > drivers/cpufreq/powernv-cpufreq.c:428:2: error: implicit declaration of > function 'get_online_cpus' [-Werror=implicit-function-declaration > > drivers/cpufreq/powernv-cpufreq.c | 19 +++++++++++-------- > 1 file changed, 11 insertions(+), 8 deletions(-) Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 547890f..140c75f 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -28,6 +28,7 @@ #include <linux/of.h> #include <linux/reboot.h> #include <linux/slab.h> +#include <linux/cpu.h> #include <asm/cputhreads.h> #include <asm/firmware.h> @@ -423,18 +424,19 @@ void powernv_cpufreq_work_fn(struct work_struct *work) { struct chip *chip = container_of(work, struct chip, throttle); unsigned int cpu; - cpumask_var_t mask; + cpumask_t mask; - smp_call_function_any(&chip->mask, + get_online_cpus(); + cpumask_and(&mask, &chip->mask, cpu_online_mask); + smp_call_function_any(&mask, powernv_cpufreq_throttle_check, NULL, 0); if (!chip->restore) - return; + goto out; chip->restore = false; - cpumask_copy(mask, &chip->mask); - for_each_cpu_and(cpu, mask, cpu_online_mask) { - int index, tcpu; + for_each_cpu(cpu, &mask) { + int index; struct cpufreq_policy policy; cpufreq_get_policy(&policy, cpu); @@ -442,9 +444,10 @@ void powernv_cpufreq_work_fn(struct work_struct *work) policy.cur, CPUFREQ_RELATION_C, &index); powernv_cpufreq_target_index(&policy, index); - for_each_cpu(tcpu, policy.cpus) - cpumask_clear_cpu(tcpu, mask); + cpumask_andnot(&mask, &mask, policy.cpus); } +out: + put_online_cpus(); } static char throttle_reason[][30] = {
In the kworker_thread powernv_cpufreq_work_fn(), we can end up sending an IPI to a cpu going offline. This is a rare corner case which is fixed using {get/put}_online_cpus(). Along with this fix, this patch adds changes to do oneshot cpumask_{clear/and} operation. Suggested-by: Shreyas B Prabhu <shreyas@linux.vnet.ibm.com> Suggested-by: Gautham R Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> --- Changes form v5: - Fix the kbuild-error: drivers/cpufreq/powernv-cpufreq.c:428:2: error: implicit declaration of function 'get_online_cpus' [-Werror=implicit-function-declaration drivers/cpufreq/powernv-cpufreq.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)