| Message ID | 1865551.sGARmvFdEr@vostro.rjw.lan (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On 08-04-16, 23:54, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Subject: [PATCH] cpufreq: Skip all governor-related actions for cpufreq_suspended set > > Since governor operations are generally skipped if cpufreq_suspended > is set, do nothing at all in cpufreq_start_governor() in that case. > > That function is called in the cpufreq_online() path, and may also > be called from cpufreq_offline() in some cases, which are invoked > by the nonboot CPUs disabing/enabling code during system suspend > to RAM and resume. That happens when all devices have been > suspended, so if the cpufreq driver relies on things like I2C to > get the current frequency, it may not be ready to do that then. > > The change here prevents problems from happening for this reason. > > Fixes: 3bbf8fe3ae08 (cpufreq: Always update current frequency before startig governor) > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > drivers/cpufreq/cpufreq.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > Index: linux-pm/drivers/cpufreq/cpufreq.c > =================================================================== > --- linux-pm.orig/drivers/cpufreq/cpufreq.c > +++ linux-pm/drivers/cpufreq/cpufreq.c > @@ -2053,6 +2053,9 @@ static int cpufreq_start_governor(struct > { > int ret; > > + if (cpufreq_suspended) > + return 0; > + > if (cpufreq_driver->get && !cpufreq_driver->setpolicy) > cpufreq_update_current_freq(policy); Since we no longer have the same check in cpufreq_exit_governor(), what about moving it to cpufreq_update_current_freq() instead? That's all we are trying to protect here anyway, as cpufreq_governor() is already protected.
On Sun, Apr 10, 2016 at 5:16 AM, Viresh Kumar <viresh.kumar@linaro.org> wrote: > On 08-04-16, 23:54, Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> Subject: [PATCH] cpufreq: Skip all governor-related actions for cpufreq_suspended set >> >> Since governor operations are generally skipped if cpufreq_suspended >> is set, do nothing at all in cpufreq_start_governor() in that case. >> >> That function is called in the cpufreq_online() path, and may also >> be called from cpufreq_offline() in some cases, which are invoked >> by the nonboot CPUs disabing/enabling code during system suspend >> to RAM and resume. That happens when all devices have been >> suspended, so if the cpufreq driver relies on things like I2C to >> get the current frequency, it may not be ready to do that then. >> >> The change here prevents problems from happening for this reason. >> >> Fixes: 3bbf8fe3ae08 (cpufreq: Always update current frequency before startig governor) >> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> >> --- >> drivers/cpufreq/cpufreq.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> Index: linux-pm/drivers/cpufreq/cpufreq.c >> =================================================================== >> --- linux-pm.orig/drivers/cpufreq/cpufreq.c >> +++ linux-pm/drivers/cpufreq/cpufreq.c >> @@ -2053,6 +2053,9 @@ static int cpufreq_start_governor(struct >> { >> int ret; >> >> + if (cpufreq_suspended) >> + return 0; >> + >> if (cpufreq_driver->get && !cpufreq_driver->setpolicy) >> cpufreq_update_current_freq(policy); > > Since we no longer have the same check in cpufreq_exit_governor(), > what about moving it to cpufreq_update_current_freq() instead? That's > all we are trying to protect here anyway, as cpufreq_governor() is > already protected. That can be done too. -- 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
Index: linux-pm/drivers/cpufreq/cpufreq.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq.c +++ linux-pm/drivers/cpufreq/cpufreq.c @@ -2053,6 +2053,9 @@ static int cpufreq_start_governor(struct { int ret; + if (cpufreq_suspended) + return 0; + if (cpufreq_driver->get && !cpufreq_driver->setpolicy) cpufreq_update_current_freq(policy);