| Message ID | 1510924566-16112-1-git-send-email-ulf.hansson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | PM / runtime: Allow an irq-safe parent to be runtime suspended | expand |
On 17 November 2017 at 14:16, Ulf Hansson <ulf.hansson@linaro.org> wrote: > When pm_runtime_irq_safe() is a called for a child device, it's assumed > that the parent is never also irq-safe. Therefore, is the parent runtime > resumed and the usage counter increased for it, as to avoid having an > irq-safe child waiting for non-irq-safe parent. > > Improve this behaviour by taking into account that the parent could also be > irq-safe. In such case let's allow it to be runtime suspended. > > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Rafael, I noticed you applied this for next, but I realized that I have overlooked a couple of more things that needs to be taken care of. Can you please drop this version? I will re-spin a new version soon. Kind regards Uffe > --- > drivers/base/power/runtime.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c > index ec059750..d44f520 100644 > --- a/drivers/base/power/runtime.c > +++ b/drivers/base/power/runtime.c > @@ -1370,13 +1370,13 @@ EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); > * Set the power.irq_safe flag, which tells the PM core that the > * ->runtime_suspend() and ->runtime_resume() callbacks for this device should > * always be invoked with the spinlock held and interrupts disabled. It also > - * causes the parent's usage counter to be permanently incremented, preventing > - * the parent from runtime suspending -- otherwise an irq-safe child might have > - * to wait for a non-irq-safe parent. > + * causes the parent's usage counter to be permanently incremented, unless the > + * parent is also irq-safe. This prevents the parent from runtime suspending, > + * otherwise an irq-safe child might have to wait for a non-irq-safe parent. > */ > void pm_runtime_irq_safe(struct device *dev) > { > - if (dev->parent) > + if (dev->parent && !pm_runtime_is_irq_safe(dev->parent)) > pm_runtime_get_sync(dev->parent); > spin_lock_irq(&dev->power.lock); > dev->power.irq_safe = 1; > @@ -1507,7 +1507,7 @@ void pm_runtime_reinit(struct device *dev) > spin_lock_irq(&dev->power.lock); > dev->power.irq_safe = 0; > spin_unlock_irq(&dev->power.lock); > - if (dev->parent) > + if (dev->parent && !pm_runtime_is_irq_safe(dev->parent)) > pm_runtime_put(dev->parent); > } > } > -- > 2.7.4 >
On Friday, December 1, 2017 8:35:50 AM CET Ulf Hansson wrote: > On 17 November 2017 at 14:16, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > When pm_runtime_irq_safe() is a called for a child device, it's assumed > > that the parent is never also irq-safe. Therefore, is the parent runtime > > resumed and the usage counter increased for it, as to avoid having an > > irq-safe child waiting for non-irq-safe parent. > > > > Improve this behaviour by taking into account that the parent could also be > > irq-safe. In such case let's allow it to be runtime suspended. > > > > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > > Rafael, I noticed you applied this for next, but I realized that I > have overlooked a couple of more things that needs to be taken care > of. > > Can you please drop this version? I will re-spin a new version soon. Will do, thanks! Rafael
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index ec059750..d44f520 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1370,13 +1370,13 @@ EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); * Set the power.irq_safe flag, which tells the PM core that the * ->runtime_suspend() and ->runtime_resume() callbacks for this device should * always be invoked with the spinlock held and interrupts disabled. It also - * causes the parent's usage counter to be permanently incremented, preventing - * the parent from runtime suspending -- otherwise an irq-safe child might have - * to wait for a non-irq-safe parent. + * causes the parent's usage counter to be permanently incremented, unless the + * parent is also irq-safe. This prevents the parent from runtime suspending, + * otherwise an irq-safe child might have to wait for a non-irq-safe parent. */ void pm_runtime_irq_safe(struct device *dev) { - if (dev->parent) + if (dev->parent && !pm_runtime_is_irq_safe(dev->parent)) pm_runtime_get_sync(dev->parent); spin_lock_irq(&dev->power.lock); dev->power.irq_safe = 1; @@ -1507,7 +1507,7 @@ void pm_runtime_reinit(struct device *dev) spin_lock_irq(&dev->power.lock); dev->power.irq_safe = 0; spin_unlock_irq(&dev->power.lock); - if (dev->parent) + if (dev->parent && !pm_runtime_is_irq_safe(dev->parent)) pm_runtime_put(dev->parent); } }
When pm_runtime_irq_safe() is a called for a child device, it's assumed that the parent is never also irq-safe. Therefore, is the parent runtime resumed and the usage counter increased for it, as to avoid having an irq-safe child waiting for non-irq-safe parent. Improve this behaviour by taking into account that the parent could also be irq-safe. In such case let's allow it to be runtime suspended. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- drivers/base/power/runtime.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) -- 2.7.4