| Message ID | 1414054881-17713-3-git-send-email-daniel.lezcano@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Thu, Oct 23, 2014 at 5:01 AM, Daniel Lezcano <daniel.lezcano@linaro.org> wrote: > In the current code, the check to reflect or not the outcoming state is done > against the idle state which has been chosen and its value. > > Instead of doing a check in each of the reflect functions, just don't call reflect > if something went wrong in the idle path. > > Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> > Acked-by: Nicolas Pitre <nico@linaro.org> > --- > drivers/cpuidle/governors/ladder.c | 3 +-- > drivers/cpuidle/governors/menu.c | 4 +--- > kernel/sched/idle.c | 3 ++- > 3 files changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c > index fb396d6..c0b36a8 100644 > --- a/drivers/cpuidle/governors/ladder.c > +++ b/drivers/cpuidle/governors/ladder.c > @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, > static void ladder_reflect(struct cpuidle_device *dev, int index) > { > struct ladder_device *ldev = &__get_cpu_var(ladder_devices); > - if (index > 0) > - ldev->last_state_idx = index; Before this patch, last_state_idx was never set to 0 here. After this patch, last_state_idx will be set to 0 when entered_state is 0. Is that okay? thanks, -Len > + ldev->last_state_idx = index; > } > > static struct cpuidle_governor ladder_governor = { > diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c > index a17515f..3907301 100644 > --- a/drivers/cpuidle/governors/menu.c > +++ b/drivers/cpuidle/governors/menu.c > @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, > static void menu_reflect(struct cpuidle_device *dev, int index) > { > struct menu_device *data = &__get_cpu_var(menu_devices); > - data->last_state_idx = index; > - if (index >= 0) > - data->needs_update = 1; > + data->needs_update = 1; > } > > /** > diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c > index 58c7522..49dcc7d 100644 > --- a/kernel/sched/idle.c > +++ b/kernel/sched/idle.c > @@ -162,7 +162,8 @@ use_default: > /* > * Give the governor an opportunity to reflect on the outcome > */ > - cpuidle_reflect(dev, entered_state); > + if (entered_state >= 0) > + cpuidle_reflect(dev, entered_state); > > exit_idle: > __current_set_polling(); > -- > 1.9.1 > > -- > 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 Thu, Oct 23, 2014 at 2:31 PM, Daniel Lezcano <daniel.lezcano@linaro.org> wrote: > In the current code, the check to reflect or not the outcoming state is done > against the idle state which has been chosen and its value. > > Instead of doing a check in each of the reflect functions, just don't call reflect > if something went wrong in the idle path. > > Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> > Acked-by: Nicolas Pitre <nico@linaro.org> > --- > drivers/cpuidle/governors/ladder.c | 3 +-- > drivers/cpuidle/governors/menu.c | 4 +--- > kernel/sched/idle.c | 3 ++- > 3 files changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c > index fb396d6..c0b36a8 100644 > --- a/drivers/cpuidle/governors/ladder.c > +++ b/drivers/cpuidle/governors/ladder.c > @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, > static void ladder_reflect(struct cpuidle_device *dev, int index) > { > struct ladder_device *ldev = &__get_cpu_var(ladder_devices); > - if (index > 0) > - ldev->last_state_idx = index; > + ldev->last_state_idx = index; > } > > static struct cpuidle_governor ladder_governor = { > diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c > index a17515f..3907301 100644 > --- a/drivers/cpuidle/governors/menu.c > +++ b/drivers/cpuidle/governors/menu.c > @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, > static void menu_reflect(struct cpuidle_device *dev, int index) > { > struct menu_device *data = &__get_cpu_var(menu_devices); > - data->last_state_idx = index; > - if (index >= 0) > - data->needs_update = 1; > + data->needs_update = 1; Why is the last_state_idx not getting updated ? Regards Preeti U Murthy
On 10/28/2014 08:01 AM, Preeti Murthy wrote: > On Thu, Oct 23, 2014 at 2:31 PM, Daniel Lezcano > <daniel.lezcano@linaro.org> wrote: >> In the current code, the check to reflect or not the outcoming state is done >> against the idle state which has been chosen and its value. >> >> Instead of doing a check in each of the reflect functions, just don't call reflect >> if something went wrong in the idle path. >> >> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> >> Acked-by: Nicolas Pitre <nico@linaro.org> >> --- >> drivers/cpuidle/governors/ladder.c | 3 +-- >> drivers/cpuidle/governors/menu.c | 4 +--- >> kernel/sched/idle.c | 3 ++- >> 3 files changed, 4 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c >> index fb396d6..c0b36a8 100644 >> --- a/drivers/cpuidle/governors/ladder.c >> +++ b/drivers/cpuidle/governors/ladder.c >> @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, >> static void ladder_reflect(struct cpuidle_device *dev, int index) >> { >> struct ladder_device *ldev = &__get_cpu_var(ladder_devices); >> - if (index > 0) >> - ldev->last_state_idx = index; >> + ldev->last_state_idx = index; >> } >> >> static struct cpuidle_governor ladder_governor = { >> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c >> index a17515f..3907301 100644 >> --- a/drivers/cpuidle/governors/menu.c >> +++ b/drivers/cpuidle/governors/menu.c >> @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, >> static void menu_reflect(struct cpuidle_device *dev, int index) >> { >> struct menu_device *data = &__get_cpu_var(menu_devices); >> - data->last_state_idx = index; >> - if (index >= 0) >> - data->needs_update = 1; >> + data->needs_update = 1; > > Why is the last_state_idx not getting updated ? Oups, right. This is missing. Thanks for pointing this out. By the way, I don't think a back end driver is changing the selected state currently and I am not sure this is desirable since we want to trust the state we are going (as a best effort). So if the 'enter' function does not change the index, that means the last_state_idx has not to be changed since it has been assigned in the 'select' function.
On 10/28/2014 03:01 AM, Len Brown wrote: > On Thu, Oct 23, 2014 at 5:01 AM, Daniel Lezcano > <daniel.lezcano@linaro.org> wrote: >> In the current code, the check to reflect or not the outcoming state is done >> against the idle state which has been chosen and its value. >> >> Instead of doing a check in each of the reflect functions, just don't call reflect >> if something went wrong in the idle path. >> >> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> >> Acked-by: Nicolas Pitre <nico@linaro.org> >> --- >> drivers/cpuidle/governors/ladder.c | 3 +-- >> drivers/cpuidle/governors/menu.c | 4 +--- >> kernel/sched/idle.c | 3 ++- >> 3 files changed, 4 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c >> index fb396d6..c0b36a8 100644 >> --- a/drivers/cpuidle/governors/ladder.c >> +++ b/drivers/cpuidle/governors/ladder.c >> @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, >> static void ladder_reflect(struct cpuidle_device *dev, int index) >> { >> struct ladder_device *ldev = &__get_cpu_var(ladder_devices); >> - if (index > 0) >> - ldev->last_state_idx = index; > > Before this patch, last_state_idx was never set to 0 here. > After this patch, last_state_idx will be set to 0 when entered_state is 0. > Is that okay? Yes, I think so because the state zero won't be never selected on x86 but on the other arch it will. So before this patch, on the other archs, the state 0 was never reflected as it should do. This is resulting from the CPUIDLE_DRIVER_STATE_START macro (I hope I can kill this macro in a couple of patchset after this one). >> + ldev->last_state_idx = index; >> } >> >> static struct cpuidle_governor ladder_governor = { >> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c >> index a17515f..3907301 100644 >> --- a/drivers/cpuidle/governors/menu.c >> +++ b/drivers/cpuidle/governors/menu.c >> @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, >> static void menu_reflect(struct cpuidle_device *dev, int index) >> { >> struct menu_device *data = &__get_cpu_var(menu_devices); >> - data->last_state_idx = index; >> - if (index >= 0) >> - data->needs_update = 1; >> + data->needs_update = 1; >> } >> >> /** >> diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c >> index 58c7522..49dcc7d 100644 >> --- a/kernel/sched/idle.c >> +++ b/kernel/sched/idle.c >> @@ -162,7 +162,8 @@ use_default: >> /* >> * Give the governor an opportunity to reflect on the outcome >> */ >> - cpuidle_reflect(dev, entered_state); >> + if (entered_state >= 0) >> + cpuidle_reflect(dev, entered_state); >> >> exit_idle: >> __current_set_polling(); >> -- >> 1.9.1 >> >> -- >> 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 10/28/2014 11:58 PM, Daniel Lezcano wrote: > On 10/28/2014 08:01 AM, Preeti Murthy wrote: >> On Thu, Oct 23, 2014 at 2:31 PM, Daniel Lezcano >> <daniel.lezcano@linaro.org> wrote: >>> In the current code, the check to reflect or not the outcoming state >>> is done >>> against the idle state which has been chosen and its value. >>> >>> Instead of doing a check in each of the reflect functions, just don't >>> call reflect >>> if something went wrong in the idle path. >>> >>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> >>> Acked-by: Nicolas Pitre <nico@linaro.org> >>> --- >>> drivers/cpuidle/governors/ladder.c | 3 +-- >>> drivers/cpuidle/governors/menu.c | 4 +--- >>> kernel/sched/idle.c | 3 ++- >>> 3 files changed, 4 insertions(+), 6 deletions(-) >>> >>> diff --git a/drivers/cpuidle/governors/ladder.c >>> b/drivers/cpuidle/governors/ladder.c >>> index fb396d6..c0b36a8 100644 >>> --- a/drivers/cpuidle/governors/ladder.c >>> +++ b/drivers/cpuidle/governors/ladder.c >>> @@ -165,8 +165,7 @@ static int ladder_enable_device(struct >>> cpuidle_driver *drv, >>> static void ladder_reflect(struct cpuidle_device *dev, int index) >>> { >>> struct ladder_device *ldev = &__get_cpu_var(ladder_devices); >>> - if (index > 0) >>> - ldev->last_state_idx = index; >>> + ldev->last_state_idx = index; >>> } >>> >>> static struct cpuidle_governor ladder_governor = { >>> diff --git a/drivers/cpuidle/governors/menu.c >>> b/drivers/cpuidle/governors/menu.c >>> index a17515f..3907301 100644 >>> --- a/drivers/cpuidle/governors/menu.c >>> +++ b/drivers/cpuidle/governors/menu.c >>> @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver >>> *drv, struct cpuidle_device *dev, >>> static void menu_reflect(struct cpuidle_device *dev, int index) >>> { >>> struct menu_device *data = &__get_cpu_var(menu_devices); >>> - data->last_state_idx = index; >>> - if (index >= 0) >>> - data->needs_update = 1; >>> + data->needs_update = 1; >> >> Why is the last_state_idx not getting updated ? > > Oups, right. This is missing. > > Thanks for pointing this out. > > By the way, I don't think a back end driver is changing the selected > state currently and I am not sure this is desirable since we want to > trust the state we are going (as a best effort). So if the 'enter' > function does not change the index, that means the last_state_idx has > not to be changed since it has been assigned in the 'select' function. Hmm Right. So you might want to remove the last_state_idx update in ladder_reflect() also? Regards Preeti U Murthy > > >
Daniel Lezcano <daniel.lezcano@linaro.org> writes: > On 10/28/2014 08:01 AM, Preeti Murthy wrote: >> On Thu, Oct 23, 2014 at 2:31 PM, Daniel Lezcano >> <daniel.lezcano@linaro.org> wrote: >>> In the current code, the check to reflect or not the outcoming state is done >>> against the idle state which has been chosen and its value. >>> >>> Instead of doing a check in each of the reflect functions, just don't call reflect >>> if something went wrong in the idle path. >>> >>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> >>> Acked-by: Nicolas Pitre <nico@linaro.org> >>> --- >>> drivers/cpuidle/governors/ladder.c | 3 +-- >>> drivers/cpuidle/governors/menu.c | 4 +--- >>> kernel/sched/idle.c | 3 ++- >>> 3 files changed, 4 insertions(+), 6 deletions(-) >>> >>> diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c >>> index fb396d6..c0b36a8 100644 >>> --- a/drivers/cpuidle/governors/ladder.c >>> +++ b/drivers/cpuidle/governors/ladder.c >>> @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, >>> static void ladder_reflect(struct cpuidle_device *dev, int index) >>> { >>> struct ladder_device *ldev = &__get_cpu_var(ladder_devices); >>> - if (index > 0) >>> - ldev->last_state_idx = index; >>> + ldev->last_state_idx = index; >>> } >>> >>> static struct cpuidle_governor ladder_governor = { >>> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c >>> index a17515f..3907301 100644 >>> --- a/drivers/cpuidle/governors/menu.c >>> +++ b/drivers/cpuidle/governors/menu.c >>> @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, >>> static void menu_reflect(struct cpuidle_device *dev, int index) >>> { >>> struct menu_device *data = &__get_cpu_var(menu_devices); >>> - data->last_state_idx = index; >>> - if (index >= 0) >>> - data->needs_update = 1; >>> + data->needs_update = 1; >> >> Why is the last_state_idx not getting updated ? > > Oups, right. This is missing. > > Thanks for pointing this out. > > By the way, I don't think a back end driver is changing the selected > state currently and I am not sure this is desirable since we want to > trust the state we are going (as a best effort). FYI, the OMAP3 backend driver can does not always obey the selected state, and will return a different state than the one requested. Kevin
On Wednesday, October 29, 2014 09:54:43 AM Kevin Hilman wrote: > Daniel Lezcano <daniel.lezcano@linaro.org> writes: > > > On 10/28/2014 08:01 AM, Preeti Murthy wrote: > >> On Thu, Oct 23, 2014 at 2:31 PM, Daniel Lezcano > >> <daniel.lezcano@linaro.org> wrote: > >>> In the current code, the check to reflect or not the outcoming state is done > >>> against the idle state which has been chosen and its value. > >>> > >>> Instead of doing a check in each of the reflect functions, just don't call reflect > >>> if something went wrong in the idle path. > >>> > >>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> > >>> Acked-by: Nicolas Pitre <nico@linaro.org> > >>> --- > >>> drivers/cpuidle/governors/ladder.c | 3 +-- > >>> drivers/cpuidle/governors/menu.c | 4 +--- > >>> kernel/sched/idle.c | 3 ++- > >>> 3 files changed, 4 insertions(+), 6 deletions(-) > >>> > >>> diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c > >>> index fb396d6..c0b36a8 100644 > >>> --- a/drivers/cpuidle/governors/ladder.c > >>> +++ b/drivers/cpuidle/governors/ladder.c > >>> @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, > >>> static void ladder_reflect(struct cpuidle_device *dev, int index) > >>> { > >>> struct ladder_device *ldev = &__get_cpu_var(ladder_devices); > >>> - if (index > 0) > >>> - ldev->last_state_idx = index; > >>> + ldev->last_state_idx = index; > >>> } > >>> > >>> static struct cpuidle_governor ladder_governor = { > >>> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c > >>> index a17515f..3907301 100644 > >>> --- a/drivers/cpuidle/governors/menu.c > >>> +++ b/drivers/cpuidle/governors/menu.c > >>> @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, > >>> static void menu_reflect(struct cpuidle_device *dev, int index) > >>> { > >>> struct menu_device *data = &__get_cpu_var(menu_devices); > >>> - data->last_state_idx = index; > >>> - if (index >= 0) > >>> - data->needs_update = 1; > >>> + data->needs_update = 1; > >> > >> Why is the last_state_idx not getting updated ? > > > > Oups, right. This is missing. > > > > Thanks for pointing this out. > > > > By the way, I don't think a back end driver is changing the selected > > state currently and I am not sure this is desirable since we want to > > trust the state we are going (as a best effort). > > FYI, the OMAP3 backend driver can does not always obey the selected > state, and will return a different state than the one requested. The ACPI driver can do that as well.
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c index fb396d6..c0b36a8 100644 --- a/drivers/cpuidle/governors/ladder.c +++ b/drivers/cpuidle/governors/ladder.c @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv, static void ladder_reflect(struct cpuidle_device *dev, int index) { struct ladder_device *ldev = &__get_cpu_var(ladder_devices); - if (index > 0) - ldev->last_state_idx = index; + ldev->last_state_idx = index; } static struct cpuidle_governor ladder_governor = { diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index a17515f..3907301 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, static void menu_reflect(struct cpuidle_device *dev, int index) { struct menu_device *data = &__get_cpu_var(menu_devices); - data->last_state_idx = index; - if (index >= 0) - data->needs_update = 1; + data->needs_update = 1; } /** diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 58c7522..49dcc7d 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -162,7 +162,8 @@ use_default: /* * Give the governor an opportunity to reflect on the outcome */ - cpuidle_reflect(dev, entered_state); + if (entered_state >= 0) + cpuidle_reflect(dev, entered_state); exit_idle: __current_set_polling();