| Message ID | 1412232900-11238-1-git-send-email-vinceh@nvidia.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 2 October 2014 12:25, Vince Hsu <vinceh@nvidia.com> wrote: > When the user space tries to set scaling_(max|min)_freq through > sysfs, the cpufreq_set_policy() asks other driver's opinions > for the max/min frequencies. Some device drivers, like Tegra > CPU EDP which is not upstreamed yet though, may constrain the > CPU maximum frequency dynamically because of board design. > So if the user space access happens and some driver is capping > the cpu frequency at the same time, the user_policy->(max|min) > is overridden by the capped value, and that's not expected by > the user space. And if the user space is not invoked again, > the CPU will always be capped by the user_policy->(max|min) > even no drivers limit the CPU frequency any more. > > This patch preserves the user specified min/max settings, so that > every time the cpufreq policy is updated, the new max/min can > be re-evaluated correctly based on the user's expection and > the present device drivers' status. > > Signed-off-by: Vince Hsu <vinceh@nvidia.com> > --- > Hi, > > I'm not sure if any platform that is supported mainlin might have this > issue, and this patch is complie tested only. Why only compiled tested? Why haven't you tested it on tegra? > drivers/cpufreq/cpufreq.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > index 24bf76fba141..c007cf2a3d2a 100644 > --- a/drivers/cpufreq/cpufreq.c > +++ b/drivers/cpufreq/cpufreq.c > @@ -524,7 +524,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, > static ssize_t store_##file_name \ > (struct cpufreq_policy *policy, const char *buf, size_t count) \ > { \ > - int ret; \ > + int ret, temp; \ > struct cpufreq_policy new_policy; \ > \ > ret = cpufreq_get_policy(&new_policy, policy->cpu); \ > @@ -535,8 +535,10 @@ static ssize_t store_##file_name \ > if (ret != 1) \ > return -EINVAL; \ > \ > + temp = new_policy.object; \ > ret = cpufreq_set_policy(policy, &new_policy); \ > - policy->user_policy.object = policy->object; \ > + if (!ret) \ > + policy->user_policy.object = temp; \ > \ > return ret ? ret : count; \ > } Looks fine otherwise. Acked-by: Viresh Kumar <viresh.kumar@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Viresh, On 10/06/2014 12:45 PM, Viresh Kumar wrote: > On 2 October 2014 12:25, Vince Hsu <vinceh@nvidia.com> wrote: >> When the user space tries to set scaling_(max|min)_freq through >> sysfs, the cpufreq_set_policy() asks other driver's opinions >> for the max/min frequencies. Some device drivers, like Tegra >> CPU EDP which is not upstreamed yet though, may constrain the >> CPU maximum frequency dynamically because of board design. >> So if the user space access happens and some driver is capping >> the cpu frequency at the same time, the user_policy->(max|min) >> is overridden by the capped value, and that's not expected by >> the user space. And if the user space is not invoked again, >> the CPU will always be capped by the user_policy->(max|min) >> even no drivers limit the CPU frequency any more. >> >> This patch preserves the user specified min/max settings, so that >> every time the cpufreq policy is updated, the new max/min can >> be re-evaluated correctly based on the user's expection and >> the present device drivers' status. >> >> Signed-off-by: Vince Hsu <vinceh@nvidia.com> >> --- >> Hi, >> >> I'm not sure if any platform that is supported mainlin might have this >> issue, and this patch is complie tested only. > Why only compiled tested? Why haven't you tested it on tegra? I did test with Chrome kernel on Tegra platform. I can't do that with mainline kernel because we haven't had the CPU EDP driver upstream yet. Thanks, Vince > >> drivers/cpufreq/cpufreq.c | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c >> index 24bf76fba141..c007cf2a3d2a 100644 >> --- a/drivers/cpufreq/cpufreq.c >> +++ b/drivers/cpufreq/cpufreq.c >> @@ -524,7 +524,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, >> static ssize_t store_##file_name \ >> (struct cpufreq_policy *policy, const char *buf, size_t count) \ >> { \ >> - int ret; \ >> + int ret, temp; \ >> struct cpufreq_policy new_policy; \ >> \ >> ret = cpufreq_get_policy(&new_policy, policy->cpu); \ >> @@ -535,8 +535,10 @@ static ssize_t store_##file_name \ >> if (ret != 1) \ >> return -EINVAL; \ >> \ >> + temp = new_policy.object; \ >> ret = cpufreq_set_policy(policy, &new_policy); \ >> - policy->user_policy.object = policy->object; \ >> + if (!ret) \ >> + policy->user_policy.object = temp; \ >> \ >> return ret ? ret : count; \ >> } > Looks fine otherwise. > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 6 October 2014 10:20, Vince Hsu <vinceh@nvidia.com> wrote: > I did test with Chrome kernel on Tegra platform. I can't do that with > mainline kernel because we haven't had the CPU EDP driver upstream yet. You should have mentioned this clearly :) Looks fine to me then. -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Viresh, Could you remind me where can I find this patch upstream? It seems this was missed? Thanks, Vince On 10/06/2014 12:50 PM, Vince Hsu wrote: > Hi Viresh, > > On 10/06/2014 12:45 PM, Viresh Kumar wrote: >> On 2 October 2014 12:25, Vince Hsu <vinceh@nvidia.com> wrote: >>> When the user space tries to set scaling_(max|min)_freq through >>> sysfs, the cpufreq_set_policy() asks other driver's opinions >>> for the max/min frequencies. Some device drivers, like Tegra >>> CPU EDP which is not upstreamed yet though, may constrain the >>> CPU maximum frequency dynamically because of board design. >>> So if the user space access happens and some driver is capping >>> the cpu frequency at the same time, the user_policy->(max|min) >>> is overridden by the capped value, and that's not expected by >>> the user space. And if the user space is not invoked again, >>> the CPU will always be capped by the user_policy->(max|min) >>> even no drivers limit the CPU frequency any more. >>> >>> This patch preserves the user specified min/max settings, so that >>> every time the cpufreq policy is updated, the new max/min can >>> be re-evaluated correctly based on the user's expection and >>> the present device drivers' status. >>> >>> Signed-off-by: Vince Hsu <vinceh@nvidia.com> >>> --- >>> Hi, >>> >>> I'm not sure if any platform that is supported mainlin might have this >>> issue, and this patch is complie tested only. >> Why only compiled tested? Why haven't you tested it on tegra? > I did test with Chrome kernel on Tegra platform. I can't do that with > mainline kernel because we haven't had the CPU EDP driver upstream yet. > > Thanks, > Vince > >> >>> drivers/cpufreq/cpufreq.c | 6 ++++-- >>> 1 file changed, 4 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c >>> index 24bf76fba141..c007cf2a3d2a 100644 >>> --- a/drivers/cpufreq/cpufreq.c >>> +++ b/drivers/cpufreq/cpufreq.c >>> @@ -524,7 +524,7 @@ static int cpufreq_set_policy(struct >>> cpufreq_policy *policy, >>> static ssize_t >>> store_##file_name \ >>> (struct cpufreq_policy *policy, const char *buf, size_t >>> count) \ >>> { \ >>> - int >>> ret; \ >>> + int ret, temp; \ >>> struct cpufreq_policy >>> new_policy; \ >>> \ >>> ret = cpufreq_get_policy(&new_policy, >>> policy->cpu); \ >>> @@ -535,8 +535,10 @@ static ssize_t >>> store_##file_name \ >>> if (ret != >>> 1) \ >>> return >>> -EINVAL; \ >>> \ >>> + temp = >>> new_policy.object; \ >>> ret = cpufreq_set_policy(policy, &new_policy); \ >>> - policy->user_policy.object = >>> policy->object; \ >>> + if >>> (!ret) \ >>> + policy->user_policy.object = >>> temp; \ >>> \ >>> return ret ? ret : >>> count; \ >>> } >> Looks fine otherwise. >> >> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 28 October 2014 08:55, Vince Hsu <vinceh@nvidia.com> wrote: > Hi Viresh, > > Could you remind me where can I find this patch upstream? It seems this was > missed? Rafael hasn't picked it up. You can normally look at the tree Rafael manages: git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git Can you please resend it to Rafael ? -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Viresh, Just sent v2 with your ACK. :) Hi Rafael, Could you please apply the v2? Thanks! Vince On 11/10/2014 01:09 PM, Viresh Kumar wrote: > On 28 October 2014 08:55, Vince Hsu <vinceh@nvidia.com> wrote: >> Hi Viresh, >> >> Could you remind me where can I find this patch upstream? It seems this was >> missed? > Rafael hasn't picked it up. You can normally look at the tree Rafael > manages: > > git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git > > Can you please resend it to Rafael ? > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 24bf76fba141..c007cf2a3d2a 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -524,7 +524,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, static ssize_t store_##file_name \ (struct cpufreq_policy *policy, const char *buf, size_t count) \ { \ - int ret; \ + int ret, temp; \ struct cpufreq_policy new_policy; \ \ ret = cpufreq_get_policy(&new_policy, policy->cpu); \ @@ -535,8 +535,10 @@ static ssize_t store_##file_name \ if (ret != 1) \ return -EINVAL; \ \ + temp = new_policy.object; \ ret = cpufreq_set_policy(policy, &new_policy); \ - policy->user_policy.object = policy->object; \ + if (!ret) \ + policy->user_policy.object = temp; \ \ return ret ? ret : count; \ }
When the user space tries to set scaling_(max|min)_freq through sysfs, the cpufreq_set_policy() asks other driver's opinions for the max/min frequencies. Some device drivers, like Tegra CPU EDP which is not upstreamed yet though, may constrain the CPU maximum frequency dynamically because of board design. So if the user space access happens and some driver is capping the cpu frequency at the same time, the user_policy->(max|min) is overridden by the capped value, and that's not expected by the user space. And if the user space is not invoked again, the CPU will always be capped by the user_policy->(max|min) even no drivers limit the CPU frequency any more. This patch preserves the user specified min/max settings, so that every time the cpufreq policy is updated, the new max/min can be re-evaluated correctly based on the user's expection and the present device drivers' status. Signed-off-by: Vince Hsu <vinceh@nvidia.com> --- Hi, I'm not sure if any platform that is supported mainlin might have this issue, and this patch is complie tested only. We hit the problem when the laptop_mode tool configures the scaling_max_freq and the Tegra CPU EDP driver is limiting the CPU maximum frequency. drivers/cpufreq/cpufreq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)