2012-06-15 12:16:51

by Deepthi Dharwar

[permalink] [raw]
Subject: Re: [PATCH] ACPI, cpuidle: Fix suspend/resume regression caused by cpuidle cleanup.

Please include this in -stable tree, as this is a regression fix which
affects older kernels ( 3.1 onwards )
Link to the patch :
http://permalink.gmane.org/gmane.linux.power-management.general/27614

Thanks !
Deepthi

On 06/14/2012 01:31 AM, Rafael J. Wysocki wrote:

> On Wednesday, June 13, 2012, Deepthi Dharwar wrote:
>>
>> From: Deepthi Dharwar <[email protected]>
>>
>> Fix suspend/resume regression caused by cpuidle cleanup.
>>
>> Commit e978aa7d7d57d04eb5f88a7507c4fb98577def77 ( cpuidle: Move
>> dev->last_residency update to driver enter routine; remove dev->last_state)
>> was breaking suspend on laptops, as reported in the below link
>> - https://lkml.org/lkml/2011/11/11/164
>>
>> This was fixed in commit 3439a8da16bcad6b0982ece938c9f8299bb53584
>> (ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression)
>> by removing acpi_idle_suspend flag.
>> - https://lkml.org/lkml/2011/11/14/74
>>
>> But this fix did not work on all systems
>> as Suspend/resume regression was reported on Lenovo S10-3
>> recently by Dave.
>> - https://lkml.org/lkml/2012/5/27/115
>> It looked like with commit e978aa7d broke suspend and
>> with commit 3439a8da resume was not working with acpi_idle driver.
>>
>> This patch fixes the regression that caused this issue
>> in the first place. acpi_idle_suspend flag is essential on
>> some x86 systems to prevent the cpus from going to deeper C-states
>> when suspend is triggered ( commit b04e7bdb984 )
>> So reverting the commit 3439a8da is essential.
>>
>> By default, irqs are disabled in cpu_idle arch specific call
>> and re-enabled in idle state return path . As the acpi_idle_suspend
>> flag was being set during suspend, which prevented the cpus
>> going to deeper idle states, it is essential to
>> enabling the irqs in its return path too.
>>
>> To address the suspend issue,
>> we were not re-enabling the interrupts while returning from
>> acpi_idle_enter_bm() routine if acpi_idle_suspend flag is set.
>> and this was causing suspend failure.
>>
>> In addition to the above fix, a sanity check has also been added
>> in x86 arch specific cpu_idle call to ensure that the idle call
>> always returns with IRQs enabled.
>>
>> This patch applies on 3.5-rc2
>> ---
>>
>> Reported-and-Tested-by: Dav Hansen <[email protected]>
>> Tested-by: Preeti Murthy <[email protected]>
>> Signed-off-by: Deepthi Dharwar <[email protected]>
>> Reviewed-by: Srivatsa S Bhat <[email protected]>
>
> Acked-by: Rafael J. Wysocki <[email protected]>
>
>> ---
>> arch/x86/kernel/process.c | 6 ++++++
>> drivers/acpi/processor_idle.c | 28 ++++++++++++++++++++++++++++
>> 2 files changed, 34 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
>> index 735279e..8ab76ad 100644
>> --- a/arch/x86/kernel/process.c
>> +++ b/arch/x86/kernel/process.c
>> @@ -460,6 +460,12 @@ void cpu_idle(void)
>> pm_idle();
>>
>> rcu_idle_exit();
>> +
>> + /*
>> + * Sanity check to ensure that idle call returns
>> + * with IRQs enabled
>> + */
>> + WARN_ON(irqs_disabled());
>> start_critical_timings();
>>
>> /* In many cases the interrupt that ended idle
>> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
>> index f3decb3..c2ffd84 100644
>> --- a/drivers/acpi/processor_idle.c
>> +++ b/drivers/acpi/processor_idle.c
>> @@ -224,6 +224,7 @@ static void lapic_timer_state_broadcast(struct acpi_processor *pr,
>> /*
>> * Suspend / resume control
>> */
>> +static int acpi_idle_suspend;
>> static u32 saved_bm_rld;
>>
>> static void acpi_idle_bm_rld_save(void)
>> @@ -242,13 +243,21 @@ static void acpi_idle_bm_rld_restore(void)
>>
>> int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
>> {
>> + if (acpi_idle_suspend == 1)
>> + return 0;
>> +
>> acpi_idle_bm_rld_save();
>> + acpi_idle_suspend = 1;
>> return 0;
>> }
>>
>> int acpi_processor_resume(struct acpi_device * device)
>> {
>> + if (acpi_idle_suspend == 0)
>> + return 0;
>> +
>> acpi_idle_bm_rld_restore();
>> + acpi_idle_suspend = 0;
>> return 0;
>> }
>>
>> @@ -754,6 +763,12 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev,
>>
>> local_irq_disable();
>>
>> + if (acpi_idle_suspend) {
>> + local_irq_enable();
>> + cpu_relax();
>> + return -EINVAL;
>> + }
>> +
>> lapic_timer_state_broadcast(pr, cx, 1);
>> kt1 = ktime_get_real();
>> acpi_idle_do_entry(cx);
>> @@ -823,6 +838,12 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
>>
>> local_irq_disable();
>>
>> + if (acpi_idle_suspend) {
>> + local_irq_enable();
>> + cpu_relax();
>> + return -EINVAL;
>> + }
>> +
>> if (cx->entry_method != ACPI_CSTATE_FFH) {
>> current_thread_info()->status &= ~TS_POLLING;
>> /*
>> @@ -901,6 +922,13 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
>> if (unlikely(!pr))
>> return -EINVAL;
>>
>> + if (acpi_idle_suspend) {
>> + if (irqs_disabled())
>> + local_irq_enable();
>> + cpu_relax();
>> + return -EINVAL;
>> + }
>> +
>> if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
>> if (drv->safe_state_index >= 0) {
>> return drv->states[drv->safe_state_index].enter(dev,
>>
>> Regards,
>> Deepthi
>>
>>
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>


2012-06-15 12:26:10

by Deepthi Dharwar

[permalink] [raw]
Subject: Re: [PATCH] ACPI, cpuidle: Fix suspend/resume regression caused by cpuidle cleanup.

Apologies for the confusion.
Please add the Cc: stable tag for this patch as this regression affects
older kernels too.
Link to the patch :
http://permalink.gmane.org/gmane.linux.power-management.general/27614

Thanks !
Deepthi

On 06/15/2012 05:46 PM, Deepthi Dharwar wrote:

> Please include this in -stable tree, as this is a regression fix which
> affects older kernels ( 3.1 onwards )


Sorry for the typo. :(

> Link to the patch :
> http://permalink.gmane.org/gmane.linux.power-management.general/27614
>
> Thanks !
> Deepthi
>
> On 06/14/2012 01:31 AM, Rafael J. Wysocki wrote:
>
>> On Wednesday, June 13, 2012, Deepthi Dharwar wrote:
>>>
>>> From: Deepthi Dharwar <[email protected]>
>>>
>>> Fix suspend/resume regression caused by cpuidle cleanup.
>>>
>>> Commit e978aa7d7d57d04eb5f88a7507c4fb98577def77 ( cpuidle: Move
>>> dev->last_residency update to driver enter routine; remove dev->last_state)
>>> was breaking suspend on laptops, as reported in the below link
>>> - https://lkml.org/lkml/2011/11/11/164
>>>
>>> This was fixed in commit 3439a8da16bcad6b0982ece938c9f8299bb53584
>>> (ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression)
>>> by removing acpi_idle_suspend flag.
>>> - https://lkml.org/lkml/2011/11/14/74
>>>
>>> But this fix did not work on all systems
>>> as Suspend/resume regression was reported on Lenovo S10-3
>>> recently by Dave.
>>> - https://lkml.org/lkml/2012/5/27/115
>>> It looked like with commit e978aa7d broke suspend and
>>> with commit 3439a8da resume was not working with acpi_idle driver.
>>>
>>> This patch fixes the regression that caused this issue
>>> in the first place. acpi_idle_suspend flag is essential on
>>> some x86 systems to prevent the cpus from going to deeper C-states
>>> when suspend is triggered ( commit b04e7bdb984 )
>>> So reverting the commit 3439a8da is essential.
>>>
>>> By default, irqs are disabled in cpu_idle arch specific call
>>> and re-enabled in idle state return path . As the acpi_idle_suspend
>>> flag was being set during suspend, which prevented the cpus
>>> going to deeper idle states, it is essential to
>>> enabling the irqs in its return path too.
>>>
>>> To address the suspend issue,
>>> we were not re-enabling the interrupts while returning from
>>> acpi_idle_enter_bm() routine if acpi_idle_suspend flag is set.
>>> and this was causing suspend failure.
>>>
>>> In addition to the above fix, a sanity check has also been added
>>> in x86 arch specific cpu_idle call to ensure that the idle call
>>> always returns with IRQs enabled.
>>>
>>> This patch applies on 3.5-rc2
>>> ---
>>>
>>> Reported-and-Tested-by: Dav Hansen <[email protected]>
>>> Tested-by: Preeti Murthy <[email protected]>
>>> Signed-off-by: Deepthi Dharwar <[email protected]>
>>> Reviewed-by: Srivatsa S Bhat <[email protected]>
>>
>> Acked-by: Rafael J. Wysocki <[email protected]>
>>
>>> ---
>>> arch/x86/kernel/process.c | 6 ++++++
>>> drivers/acpi/processor_idle.c | 28 ++++++++++++++++++++++++++++
>>> 2 files changed, 34 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
>>> index 735279e..8ab76ad 100644
>>> --- a/arch/x86/kernel/process.c
>>> +++ b/arch/x86/kernel/process.c
>>> @@ -460,6 +460,12 @@ void cpu_idle(void)
>>> pm_idle();
>>>
>>> rcu_idle_exit();
>>> +
>>> + /*
>>> + * Sanity check to ensure that idle call returns
>>> + * with IRQs enabled
>>> + */
>>> + WARN_ON(irqs_disabled());
>>> start_critical_timings();
>>>
>>> /* In many cases the interrupt that ended idle
>>> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
>>> index f3decb3..c2ffd84 100644
>>> --- a/drivers/acpi/processor_idle.c
>>> +++ b/drivers/acpi/processor_idle.c
>>> @@ -224,6 +224,7 @@ static void lapic_timer_state_broadcast(struct acpi_processor *pr,
>>> /*
>>> * Suspend / resume control
>>> */
>>> +static int acpi_idle_suspend;
>>> static u32 saved_bm_rld;
>>>
>>> static void acpi_idle_bm_rld_save(void)
>>> @@ -242,13 +243,21 @@ static void acpi_idle_bm_rld_restore(void)
>>>
>>> int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
>>> {
>>> + if (acpi_idle_suspend == 1)
>>> + return 0;
>>> +
>>> acpi_idle_bm_rld_save();
>>> + acpi_idle_suspend = 1;
>>> return 0;
>>> }
>>>
>>> int acpi_processor_resume(struct acpi_device * device)
>>> {
>>> + if (acpi_idle_suspend == 0)
>>> + return 0;
>>> +
>>> acpi_idle_bm_rld_restore();
>>> + acpi_idle_suspend = 0;
>>> return 0;
>>> }
>>>
>>> @@ -754,6 +763,12 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev,
>>>
>>> local_irq_disable();
>>>
>>> + if (acpi_idle_suspend) {
>>> + local_irq_enable();
>>> + cpu_relax();
>>> + return -EINVAL;
>>> + }
>>> +
>>> lapic_timer_state_broadcast(pr, cx, 1);
>>> kt1 = ktime_get_real();
>>> acpi_idle_do_entry(cx);
>>> @@ -823,6 +838,12 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
>>>
>>> local_irq_disable();
>>>
>>> + if (acpi_idle_suspend) {
>>> + local_irq_enable();
>>> + cpu_relax();
>>> + return -EINVAL;
>>> + }
>>> +
>>> if (cx->entry_method != ACPI_CSTATE_FFH) {
>>> current_thread_info()->status &= ~TS_POLLING;
>>> /*
>>> @@ -901,6 +922,13 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
>>> if (unlikely(!pr))
>>> return -EINVAL;
>>>
>>> + if (acpi_idle_suspend) {
>>> + if (irqs_disabled())
>>> + local_irq_enable();
>>> + cpu_relax();
>>> + return -EINVAL;
>>> + }
>>> +
>>> if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
>>> if (drv->safe_state_index >= 0) {
>>> return drv->states[drv->safe_state_index].enter(dev,
>>>
>>> Regards,
>>> Deepthi
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
>> the body of a message to [email protected]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>
>

2012-06-15 12:28:07

by Deepthi Dharwar

[permalink] [raw]
Subject: Re: [PATCH] ACPI, cpuidle: Fix suspend/resume regression caused by cpuidle cleanup.

Apologies for the confusion.
Please add the Cc: stable tag for this patch as this regression affects
older kernels too.
Link to the patch :
http://permalink.gmane.org/gmane.linux.power-management.general/27614

Thanks !
Deepthi

On 06/15/2012 05:46 PM, Deepthi Dharwar wrote:

> Please include this in -stable tree, as this is a regression fix which
> affects older kernels ( 3.1 onwards )
> Link to the patch :
> http://permalink.gmane.org/gmane.linux.power-management.general/27614
>
> Thanks !
> Deepthi
>
> On 06/14/2012 01:31 AM, Rafael J. Wysocki wrote:
>
>> On Wednesday, June 13, 2012, Deepthi Dharwar wrote:
>>>
>>> From: Deepthi Dharwar <[email protected]>
>>>
>>> Fix suspend/resume regression caused by cpuidle cleanup.
>>>
>>> Commit e978aa7d7d57d04eb5f88a7507c4fb98577def77 ( cpuidle: Move
>>> dev->last_residency update to driver enter routine; remove dev->last_state)
>>> was breaking suspend on laptops, as reported in the below link
>>> - https://lkml.org/lkml/2011/11/11/164
>>>
>>> This was fixed in commit 3439a8da16bcad6b0982ece938c9f8299bb53584
>>> (ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression)
>>> by removing acpi_idle_suspend flag.
>>> - https://lkml.org/lkml/2011/11/14/74
>>>
>>> But this fix did not work on all systems
>>> as Suspend/resume regression was reported on Lenovo S10-3
>>> recently by Dave.
>>> - https://lkml.org/lkml/2012/5/27/115
>>> It looked like with commit e978aa7d broke suspend and
>>> with commit 3439a8da resume was not working with acpi_idle driver.
>>>
>>> This patch fixes the regression that caused this issue
>>> in the first place. acpi_idle_suspend flag is essential on
>>> some x86 systems to prevent the cpus from going to deeper C-states
>>> when suspend is triggered ( commit b04e7bdb984 )
>>> So reverting the commit 3439a8da is essential.
>>>
>>> By default, irqs are disabled in cpu_idle arch specific call
>>> and re-enabled in idle state return path . As the acpi_idle_suspend
>>> flag was being set during suspend, which prevented the cpus
>>> going to deeper idle states, it is essential to
>>> enabling the irqs in its return path too.
>>>
>>> To address the suspend issue,
>>> we were not re-enabling the interrupts while returning from
>>> acpi_idle_enter_bm() routine if acpi_idle_suspend flag is set.
>>> and this was causing suspend failure.
>>>
>>> In addition to the above fix, a sanity check has also been added
>>> in x86 arch specific cpu_idle call to ensure that the idle call
>>> always returns with IRQs enabled.
>>>
>>> This patch applies on 3.5-rc2
>>> ---
>>>
>>> Reported-and-Tested-by: Dav Hansen <[email protected]>
>>> Tested-by: Preeti Murthy <[email protected]>
>>> Signed-off-by: Deepthi Dharwar <[email protected]>
>>> Reviewed-by: Srivatsa S Bhat <[email protected]>
>>
>> Acked-by: Rafael J. Wysocki <[email protected]>
>>
>>> ---
>>> arch/x86/kernel/process.c | 6 ++++++
>>> drivers/acpi/processor_idle.c | 28 ++++++++++++++++++++++++++++
>>> 2 files changed, 34 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
>>> index 735279e..8ab76ad 100644
>>> --- a/arch/x86/kernel/process.c
>>> +++ b/arch/x86/kernel/process.c
>>> @@ -460,6 +460,12 @@ void cpu_idle(void)
>>> pm_idle();
>>>
>>> rcu_idle_exit();
>>> +
>>> + /*
>>> + * Sanity check to ensure that idle call returns
>>> + * with IRQs enabled
>>> + */
>>> + WARN_ON(irqs_disabled());
>>> start_critical_timings();
>>>
>>> /* In many cases the interrupt that ended idle
>>> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
>>> index f3decb3..c2ffd84 100644
>>> --- a/drivers/acpi/processor_idle.c
>>> +++ b/drivers/acpi/processor_idle.c
>>> @@ -224,6 +224,7 @@ static void lapic_timer_state_broadcast(struct acpi_processor *pr,
>>> /*
>>> * Suspend / resume control
>>> */
>>> +static int acpi_idle_suspend;
>>> static u32 saved_bm_rld;
>>>
>>> static void acpi_idle_bm_rld_save(void)
>>> @@ -242,13 +243,21 @@ static void acpi_idle_bm_rld_restore(void)
>>>
>>> int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
>>> {
>>> + if (acpi_idle_suspend == 1)
>>> + return 0;
>>> +
>>> acpi_idle_bm_rld_save();
>>> + acpi_idle_suspend = 1;
>>> return 0;
>>> }
>>>
>>> int acpi_processor_resume(struct acpi_device * device)
>>> {
>>> + if (acpi_idle_suspend == 0)
>>> + return 0;
>>> +
>>> acpi_idle_bm_rld_restore();
>>> + acpi_idle_suspend = 0;
>>> return 0;
>>> }
>>>
>>> @@ -754,6 +763,12 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev,
>>>
>>> local_irq_disable();
>>>
>>> + if (acpi_idle_suspend) {
>>> + local_irq_enable();
>>> + cpu_relax();
>>> + return -EINVAL;
>>> + }
>>> +
>>> lapic_timer_state_broadcast(pr, cx, 1);
>>> kt1 = ktime_get_real();
>>> acpi_idle_do_entry(cx);
>>> @@ -823,6 +838,12 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
>>>
>>> local_irq_disable();
>>>
>>> + if (acpi_idle_suspend) {
>>> + local_irq_enable();
>>> + cpu_relax();
>>> + return -EINVAL;
>>> + }
>>> +
>>> if (cx->entry_method != ACPI_CSTATE_FFH) {
>>> current_thread_info()->status &= ~TS_POLLING;
>>> /*
>>> @@ -901,6 +922,13 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
>>> if (unlikely(!pr))
>>> return -EINVAL;
>>>
>>> + if (acpi_idle_suspend) {
>>> + if (irqs_disabled())
>>> + local_irq_enable();
>>> + cpu_relax();
>>> + return -EINVAL;
>>> + }
>>> +
>>> if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
>>> if (drv->safe_state_index >= 0) {
>>> return drv->states[drv->safe_state_index].enter(dev,
>>>
>>> Regards,
>>> Deepthi
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
>> the body of a message to [email protected]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>
>