* [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM
@ 2017-12-01 13:58 Rafael J. Wysocki
2017-12-01 14:18 ` Lukas Wunner
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Rafael J. Wysocki @ 2017-12-01 13:58 UTC (permalink / raw)
To: Linux PM; +Cc: LKML, Adrian Hunter, Lukas Wunner, Greg Kroah-Hartman
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Prevent rpm_get_suppliers() from returning an error code if runtime
PM is disabled for one or more of the supplier devices it wants to
runtime-resume, so as to make runtime PM work for devices with links
to suppliers that don't use runtime PM (such links may be created
during device enumeration even before it is known whether or not
runtime PM will be enabled for the devices in question, for example).
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: 21d5c57b3726 (PM / runtime: Use device links)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/base/power/runtime.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
Index: linux-pm/drivers/base/power/runtime.c
===================================================================
--- linux-pm.orig/drivers/base/power/runtime.c
+++ linux-pm/drivers/base/power/runtime.c
@@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
continue;
retval = pm_runtime_get_sync(link->supplier);
- if (retval < 0) {
+ /* Ignore suppliers with disabled runtime PM. */
+ if (retval < 0 && retval != -EACCES) {
pm_runtime_put_noidle(link->supplier);
return retval;
}
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM
2017-12-01 13:58 [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM Rafael J. Wysocki
@ 2017-12-01 14:18 ` Lukas Wunner
2017-12-01 14:29 ` Rafael J. Wysocki
2017-12-01 14:34 ` Rafael J. Wysocki
2017-12-04 11:51 ` Adrian Hunter
2017-12-07 19:48 ` Ulf Hansson
2 siblings, 2 replies; 6+ messages in thread
From: Lukas Wunner @ 2017-12-01 14:18 UTC (permalink / raw)
To: Rafael J. Wysocki; +Cc: Linux PM, LKML, Adrian Hunter, Greg Kroah-Hartman
On Fri, Dec 01, 2017 at 02:58:34PM +0100, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Prevent rpm_get_suppliers() from returning an error code if runtime
> PM is disabled for one or more of the supplier devices it wants to
> runtime-resume, so as to make runtime PM work for devices with links
> to suppliers that don't use runtime PM (such links may be created
> during device enumeration even before it is known whether or not
> runtime PM will be enabled for the devices in question, for example).
>
> Reported-by: Adrian Hunter <adrian.hunter@intel.com>
> Fixes: 21d5c57b3726 (PM / runtime: Use device links)
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
> drivers/base/power/runtime.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> Index: linux-pm/drivers/base/power/runtime.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/runtime.c
> +++ linux-pm/drivers/base/power/runtime.c
> @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
> continue;
>
> retval = pm_runtime_get_sync(link->supplier);
> - if (retval < 0) {
> + /* Ignore suppliers with disabled runtime PM. */
> + if (retval < 0 && retval != -EACCES) {
> pm_runtime_put_noidle(link->supplier);
> return retval;
> }
>
You could alternatively call pm_runtime_get_sync() under the condition
link->supplier->power.disable_depth > 0 but then the usage_count wouldn't
be incremented and I guess we want that in case runtime PM is only
temporarily disabled and later enabled, right?
I'm wondering if checking for that condition in lieu of retval != -EACCES
would be more explicit and less fragile here (there's a theoretical
possibility that the supplier's ->runtime_resume callback returns -EACCESS,
leading to a false positive).
Apart from that,
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Thanks,
Lukas
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM
2017-12-01 14:18 ` Lukas Wunner
@ 2017-12-01 14:29 ` Rafael J. Wysocki
2017-12-01 14:34 ` Rafael J. Wysocki
1 sibling, 0 replies; 6+ messages in thread
From: Rafael J. Wysocki @ 2017-12-01 14:29 UTC (permalink / raw)
To: Lukas Wunner; +Cc: Linux PM, LKML, Adrian Hunter, Greg Kroah-Hartman
On Friday, December 1, 2017 3:18:01 PM CET Lukas Wunner wrote:
> On Fri, Dec 01, 2017 at 02:58:34PM +0100, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > Prevent rpm_get_suppliers() from returning an error code if runtime
> > PM is disabled for one or more of the supplier devices it wants to
> > runtime-resume, so as to make runtime PM work for devices with links
> > to suppliers that don't use runtime PM (such links may be created
> > during device enumeration even before it is known whether or not
> > runtime PM will be enabled for the devices in question, for example).
> >
> > Reported-by: Adrian Hunter <adrian.hunter@intel.com>
> > Fixes: 21d5c57b3726 (PM / runtime: Use device links)
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > ---
> > drivers/base/power/runtime.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > Index: linux-pm/drivers/base/power/runtime.c
> > ===================================================================
> > --- linux-pm.orig/drivers/base/power/runtime.c
> > +++ linux-pm/drivers/base/power/runtime.c
> > @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
> > continue;
> >
> > retval = pm_runtime_get_sync(link->supplier);
> > - if (retval < 0) {
> > + /* Ignore suppliers with disabled runtime PM. */
> > + if (retval < 0 && retval != -EACCES) {
> > pm_runtime_put_noidle(link->supplier);
> > return retval;
> > }
> >
>
> You could alternatively call pm_runtime_get_sync() under the condition
> link->supplier->power.disable_depth > 0 but then the usage_count wouldn't
> be incremented and I guess we want that in case runtime PM is only
> temporarily disabled and later enabled, right?
>
> I'm wondering if checking for that condition in lieu of retval != -EACCES
> would be more explicit and less fragile here (there's a theoretical
> possibility that the supplier's ->runtime_resume callback returns -EACCESS,
> leading to a false positive).
That will be filtered out by rpm_callback() which converts -EACCES to -EIO.
>
> Apart from that,
>
> Reviewed-by: Lukas Wunner <lukas@wunner.de>
Thanks,
Rafael
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM
2017-12-01 14:18 ` Lukas Wunner
2017-12-01 14:29 ` Rafael J. Wysocki
@ 2017-12-01 14:34 ` Rafael J. Wysocki
1 sibling, 0 replies; 6+ messages in thread
From: Rafael J. Wysocki @ 2017-12-01 14:34 UTC (permalink / raw)
To: Lukas Wunner
Cc: Rafael J. Wysocki, Linux PM, LKML, Adrian Hunter, Greg Kroah-Hartman
On Fri, Dec 1, 2017 at 3:18 PM, Lukas Wunner <lukas@wunner.de> wrote:
> On Fri, Dec 01, 2017 at 02:58:34PM +0100, Rafael J. Wysocki wrote:
>> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>
>> Prevent rpm_get_suppliers() from returning an error code if runtime
>> PM is disabled for one or more of the supplier devices it wants to
>> runtime-resume, so as to make runtime PM work for devices with links
>> to suppliers that don't use runtime PM (such links may be created
>> during device enumeration even before it is known whether or not
>> runtime PM will be enabled for the devices in question, for example).
>>
>> Reported-by: Adrian Hunter <adrian.hunter@intel.com>
>> Fixes: 21d5c57b3726 (PM / runtime: Use device links)
>> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>> ---
>> drivers/base/power/runtime.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> Index: linux-pm/drivers/base/power/runtime.c
>> ===================================================================
>> --- linux-pm.orig/drivers/base/power/runtime.c
>> +++ linux-pm/drivers/base/power/runtime.c
>> @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
>> continue;
>>
>> retval = pm_runtime_get_sync(link->supplier);
>> - if (retval < 0) {
>> + /* Ignore suppliers with disabled runtime PM. */
>> + if (retval < 0 && retval != -EACCES) {
>> pm_runtime_put_noidle(link->supplier);
>> return retval;
>> }
>>
>
> You could alternatively call pm_runtime_get_sync() under the condition
> link->supplier->power.disable_depth > 0 but then the usage_count wouldn't
> be incremented and I guess we want that in case runtime PM is only
> temporarily disabled and later enabled, right?
Right.
Thanks,
Rafael
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM
2017-12-01 13:58 [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM Rafael J. Wysocki
2017-12-01 14:18 ` Lukas Wunner
@ 2017-12-04 11:51 ` Adrian Hunter
2017-12-07 19:48 ` Ulf Hansson
2 siblings, 0 replies; 6+ messages in thread
From: Adrian Hunter @ 2017-12-04 11:51 UTC (permalink / raw)
To: Rafael J. Wysocki, Linux PM; +Cc: LKML, Lukas Wunner, Greg Kroah-Hartman
On 01/12/17 15:58, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Prevent rpm_get_suppliers() from returning an error code if runtime
> PM is disabled for one or more of the supplier devices it wants to
> runtime-resume, so as to make runtime PM work for devices with links
> to suppliers that don't use runtime PM (such links may be created
> during device enumeration even before it is known whether or not
> runtime PM will be enabled for the devices in question, for example).
>
> Reported-by: Adrian Hunter <adrian.hunter@intel.com>
> Fixes: 21d5c57b3726 (PM / runtime: Use device links)
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
> drivers/base/power/runtime.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> Index: linux-pm/drivers/base/power/runtime.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/runtime.c
> +++ linux-pm/drivers/base/power/runtime.c
> @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
> continue;
>
> retval = pm_runtime_get_sync(link->supplier);
> - if (retval < 0) {
> + /* Ignore suppliers with disabled runtime PM. */
> + if (retval < 0 && retval != -EACCES) {
> pm_runtime_put_noidle(link->supplier);
> return retval;
> }
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM
2017-12-01 13:58 [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM Rafael J. Wysocki
2017-12-01 14:18 ` Lukas Wunner
2017-12-04 11:51 ` Adrian Hunter
@ 2017-12-07 19:48 ` Ulf Hansson
2 siblings, 0 replies; 6+ messages in thread
From: Ulf Hansson @ 2017-12-07 19:48 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: Linux PM, LKML, Adrian Hunter, Lukas Wunner, Greg Kroah-Hartman
On 1 December 2017 at 14:58, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Prevent rpm_get_suppliers() from returning an error code if runtime
> PM is disabled for one or more of the supplier devices it wants to
> runtime-resume, so as to make runtime PM work for devices with links
> to suppliers that don't use runtime PM (such links may be created
> during device enumeration even before it is known whether or not
> runtime PM will be enabled for the devices in question, for example).
>
> Reported-by: Adrian Hunter <adrian.hunter@intel.com>
> Fixes: 21d5c57b3726 (PM / runtime: Use device links)
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Kind regards
Uffe
> ---
> drivers/base/power/runtime.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> Index: linux-pm/drivers/base/power/runtime.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/runtime.c
> +++ linux-pm/drivers/base/power/runtime.c
> @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
> continue;
>
> retval = pm_runtime_get_sync(link->supplier);
> - if (retval < 0) {
> + /* Ignore suppliers with disabled runtime PM. */
> + if (retval < 0 && retval != -EACCES) {
> pm_runtime_put_noidle(link->supplier);
> return retval;
> }
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-12-07 19:48 UTC | newest]
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2017-12-01 13:58 [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM Rafael J. Wysocki
2017-12-01 14:18 ` Lukas Wunner
2017-12-01 14:29 ` Rafael J. Wysocki
2017-12-01 14:34 ` Rafael J. Wysocki
2017-12-04 11:51 ` Adrian Hunter
2017-12-07 19:48 ` Ulf Hansson
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