* [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled
@ 2021-01-18 13:09 ` Kai-Heng Feng
0 siblings, 0 replies; 6+ messages in thread
From: Kai-Heng Feng @ 2021-01-18 13:09 UTC (permalink / raw)
To: tiwai
Cc: moderated list:SOUND, Kai Vehmanen, Harsha Priya, open list,
Mark Brown, Pierre-Louis Bossart, Ranjani Sridharan,
Kai-Heng Feng, Kenneth R . Crudup
HDA controller can't be runtime-suspended after commit 215a22ed31a1
("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
which enables direct-complete for HDA codec.
The HDA codec driver didn't expect direct-complete will be disabled
after it returns a positive value from prepare() callback. However,
there are some places that PM core can disable direct-complete. For
instance, system hibernation or when codec has subordinates like LEDs.
So if a device is prepared for direct-complete but PM core still calls
codec's suspend or freeze callback, resume the device to keep PM
operations balanced.
Reported-by: Kenneth R. Crudup <kenny@panix.com>
Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
sound/pci/hda/hda_codec.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 687216e74526..0afbced979df 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -2997,6 +2997,9 @@ static void hda_codec_pm_complete(struct device *dev)
static int hda_codec_pm_suspend(struct device *dev)
{
+ if (pm_runtime_status_suspended(dev))
+ pm_runtime_resume(dev);
+
dev->power.power_state = PMSG_SUSPEND;
return hda_codec_suspend(dev);
}
@@ -3009,6 +3012,9 @@ static int hda_codec_pm_resume(struct device *dev)
static int hda_codec_pm_freeze(struct device *dev)
{
+ if (pm_runtime_status_suspended(dev))
+ pm_runtime_resume(dev);
+
dev->power.power_state = PMSG_FREEZE;
return hda_codec_suspend(dev);
}
--
2.29.2
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled
@ 2021-01-18 13:09 ` Kai-Heng Feng
0 siblings, 0 replies; 6+ messages in thread
From: Kai-Heng Feng @ 2021-01-18 13:09 UTC (permalink / raw)
To: tiwai
Cc: Kai-Heng Feng, Kenneth R . Crudup, Jaroslav Kysela,
Pierre-Louis Bossart, Kai Vehmanen, Ranjani Sridharan, Mark Brown,
Harsha Priya, moderated list:SOUND, open list
HDA controller can't be runtime-suspended after commit 215a22ed31a1
("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
which enables direct-complete for HDA codec.
The HDA codec driver didn't expect direct-complete will be disabled
after it returns a positive value from prepare() callback. However,
there are some places that PM core can disable direct-complete. For
instance, system hibernation or when codec has subordinates like LEDs.
So if a device is prepared for direct-complete but PM core still calls
codec's suspend or freeze callback, resume the device to keep PM
operations balanced.
Reported-by: Kenneth R. Crudup <kenny@panix.com>
Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
sound/pci/hda/hda_codec.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 687216e74526..0afbced979df 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -2997,6 +2997,9 @@ static void hda_codec_pm_complete(struct device *dev)
static int hda_codec_pm_suspend(struct device *dev)
{
+ if (pm_runtime_status_suspended(dev))
+ pm_runtime_resume(dev);
+
dev->power.power_state = PMSG_SUSPEND;
return hda_codec_suspend(dev);
}
@@ -3009,6 +3012,9 @@ static int hda_codec_pm_resume(struct device *dev)
static int hda_codec_pm_freeze(struct device *dev)
{
+ if (pm_runtime_status_suspended(dev))
+ pm_runtime_resume(dev);
+
dev->power.power_state = PMSG_FREEZE;
return hda_codec_suspend(dev);
}
--
2.29.2
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled
2021-01-18 13:09 ` Kai-Heng Feng
@ 2021-01-18 13:21 ` Takashi Iwai
-1 siblings, 0 replies; 6+ messages in thread
From: Takashi Iwai @ 2021-01-18 13:21 UTC (permalink / raw)
To: Kai-Heng Feng
Cc: moderated list:SOUND, Kai Vehmanen, Harsha Priya, open list,
tiwai, Pierre-Louis Bossart, Mark Brown, Ranjani Sridharan,
Kenneth R . Crudup
On Mon, 18 Jan 2021 14:09:36 +0100,
Kai-Heng Feng wrote:
>
> HDA controller can't be runtime-suspended after commit 215a22ed31a1
> ("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
> which enables direct-complete for HDA codec.
>
> The HDA codec driver didn't expect direct-complete will be disabled
> after it returns a positive value from prepare() callback. However,
> there are some places that PM core can disable direct-complete. For
> instance, system hibernation or when codec has subordinates like LEDs.
Hmm. This sounds rather like the approach using the direct-complete
isn't well suited for the purpose? The increasing number of
regression reports worries me.
> So if a device is prepared for direct-complete but PM core still calls
> codec's suspend or freeze callback, resume the device to keep PM
> operations balanced.
I find the ping-pong of the resume/suspend there a bit odd. It's no
refcount management but it invokes the real resume there, which is
involved with lots of operations.
Can we rather skip the hda_codec_suspend() call instead (while
changing dev->power.power_state)?
thanks,
Takashi
> Reported-by: Kenneth R. Crudup <kenny@panix.com>
> Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> ---
> sound/pci/hda/hda_codec.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
> index 687216e74526..0afbced979df 100644
> --- a/sound/pci/hda/hda_codec.c
> +++ b/sound/pci/hda/hda_codec.c
> @@ -2997,6 +2997,9 @@ static void hda_codec_pm_complete(struct device *dev)
>
> static int hda_codec_pm_suspend(struct device *dev)
> {
> + if (pm_runtime_status_suspended(dev))
> + pm_runtime_resume(dev);
> +
> dev->power.power_state = PMSG_SUSPEND;
> return hda_codec_suspend(dev);
> }
> @@ -3009,6 +3012,9 @@ static int hda_codec_pm_resume(struct device *dev)
>
> static int hda_codec_pm_freeze(struct device *dev)
> {
> + if (pm_runtime_status_suspended(dev))
> + pm_runtime_resume(dev);
> +
> dev->power.power_state = PMSG_FREEZE;
> return hda_codec_suspend(dev);
> }
> --
> 2.29.2
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled
@ 2021-01-18 13:21 ` Takashi Iwai
0 siblings, 0 replies; 6+ messages in thread
From: Takashi Iwai @ 2021-01-18 13:21 UTC (permalink / raw)
To: Kai-Heng Feng
Cc: tiwai, Kenneth R . Crudup, Jaroslav Kysela, Pierre-Louis Bossart,
Kai Vehmanen, Ranjani Sridharan, Mark Brown, Harsha Priya,
moderated list:SOUND, open list
On Mon, 18 Jan 2021 14:09:36 +0100,
Kai-Heng Feng wrote:
>
> HDA controller can't be runtime-suspended after commit 215a22ed31a1
> ("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
> which enables direct-complete for HDA codec.
>
> The HDA codec driver didn't expect direct-complete will be disabled
> after it returns a positive value from prepare() callback. However,
> there are some places that PM core can disable direct-complete. For
> instance, system hibernation or when codec has subordinates like LEDs.
Hmm. This sounds rather like the approach using the direct-complete
isn't well suited for the purpose? The increasing number of
regression reports worries me.
> So if a device is prepared for direct-complete but PM core still calls
> codec's suspend or freeze callback, resume the device to keep PM
> operations balanced.
I find the ping-pong of the resume/suspend there a bit odd. It's no
refcount management but it invokes the real resume there, which is
involved with lots of operations.
Can we rather skip the hda_codec_suspend() call instead (while
changing dev->power.power_state)?
thanks,
Takashi
> Reported-by: Kenneth R. Crudup <kenny@panix.com>
> Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> ---
> sound/pci/hda/hda_codec.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
> index 687216e74526..0afbced979df 100644
> --- a/sound/pci/hda/hda_codec.c
> +++ b/sound/pci/hda/hda_codec.c
> @@ -2997,6 +2997,9 @@ static void hda_codec_pm_complete(struct device *dev)
>
> static int hda_codec_pm_suspend(struct device *dev)
> {
> + if (pm_runtime_status_suspended(dev))
> + pm_runtime_resume(dev);
> +
> dev->power.power_state = PMSG_SUSPEND;
> return hda_codec_suspend(dev);
> }
> @@ -3009,6 +3012,9 @@ static int hda_codec_pm_resume(struct device *dev)
>
> static int hda_codec_pm_freeze(struct device *dev)
> {
> + if (pm_runtime_status_suspended(dev))
> + pm_runtime_resume(dev);
> +
> dev->power.power_state = PMSG_FREEZE;
> return hda_codec_suspend(dev);
> }
> --
> 2.29.2
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled
2021-01-18 13:21 ` Takashi Iwai
@ 2021-01-18 17:27 ` Kai-Heng Feng
-1 siblings, 0 replies; 6+ messages in thread
From: Kai-Heng Feng @ 2021-01-18 17:27 UTC (permalink / raw)
To: Takashi Iwai
Cc: moderated list:SOUND, Kai Vehmanen, Harsha Priya, open list,
Takashi Iwai, Pierre-Louis Bossart, Mark Brown, Ranjani Sridharan,
Kenneth R . Crudup
On Mon, Jan 18, 2021 at 9:21 PM Takashi Iwai <tiwai@suse.de> wrote:
>
> On Mon, 18 Jan 2021 14:09:36 +0100,
> Kai-Heng Feng wrote:
> >
> > HDA controller can't be runtime-suspended after commit 215a22ed31a1
> > ("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
> > which enables direct-complete for HDA codec.
> >
> > The HDA codec driver didn't expect direct-complete will be disabled
> > after it returns a positive value from prepare() callback. However,
> > there are some places that PM core can disable direct-complete. For
> > instance, system hibernation or when codec has subordinates like LEDs.
>
> Hmm. This sounds rather like the approach using the direct-complete
> isn't well suited for the purpose? The increasing number of
> regression reports worries me.
Direct-complete works fine on HDA controller but so far not so on HDA codec.
I think the main reason is that the codec doesn't have the middle
layer to handle the detail, while HDA controller has PCI bus to deal
with them.
>
> > So if a device is prepared for direct-complete but PM core still calls
> > codec's suspend or freeze callback, resume the device to keep PM
> > operations balanced.
>
> I find the ping-pong of the resume/suspend there a bit odd. It's no
> refcount management but it invokes the real resume there, which is
> involved with lots of operations.
Yes. I'll find a better approach to address this.
>
> Can we rather skip the hda_codec_suspend() call instead (while
> changing dev->power.power_state)?
Maybe we can revert the most of the commit, and just leave
hda_codec_pm_complete(), which is the most relevant part of the patch.
Let me test a bit and send a new patch. Let me know if you don't like
this approach.
A question a bit unrelated to the discussion - how does
snd_hdac_power_up_pm() work for concurrent resume?
It can work for recursive call, but what if there are concurrent
resume request, but pm_runtime_get_sync() is still running?
The second call may access the codec which hasn't completed resume.
Kai-Heng
>
>
> thanks,
>
> Takashi
>
> > Reported-by: Kenneth R. Crudup <kenny@panix.com>
> > Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> > ---
> > sound/pci/hda/hda_codec.c | 6 ++++++
> > 1 file changed, 6 insertions(+)
> >
> > diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
> > index 687216e74526..0afbced979df 100644
> > --- a/sound/pci/hda/hda_codec.c
> > +++ b/sound/pci/hda/hda_codec.c
> > @@ -2997,6 +2997,9 @@ static void hda_codec_pm_complete(struct device *dev)
> >
> > static int hda_codec_pm_suspend(struct device *dev)
> > {
> > + if (pm_runtime_status_suspended(dev))
> > + pm_runtime_resume(dev);
> > +
> > dev->power.power_state = PMSG_SUSPEND;
> > return hda_codec_suspend(dev);
> > }
> > @@ -3009,6 +3012,9 @@ static int hda_codec_pm_resume(struct device *dev)
> >
> > static int hda_codec_pm_freeze(struct device *dev)
> > {
> > + if (pm_runtime_status_suspended(dev))
> > + pm_runtime_resume(dev);
> > +
> > dev->power.power_state = PMSG_FREEZE;
> > return hda_codec_suspend(dev);
> > }
> > --
> > 2.29.2
> >
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled
@ 2021-01-18 17:27 ` Kai-Heng Feng
0 siblings, 0 replies; 6+ messages in thread
From: Kai-Heng Feng @ 2021-01-18 17:27 UTC (permalink / raw)
To: Takashi Iwai
Cc: Takashi Iwai, Kenneth R . Crudup, Jaroslav Kysela,
Pierre-Louis Bossart, Kai Vehmanen, Ranjani Sridharan, Mark Brown,
Harsha Priya, moderated list:SOUND, open list
On Mon, Jan 18, 2021 at 9:21 PM Takashi Iwai <tiwai@suse.de> wrote:
>
> On Mon, 18 Jan 2021 14:09:36 +0100,
> Kai-Heng Feng wrote:
> >
> > HDA controller can't be runtime-suspended after commit 215a22ed31a1
> > ("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
> > which enables direct-complete for HDA codec.
> >
> > The HDA codec driver didn't expect direct-complete will be disabled
> > after it returns a positive value from prepare() callback. However,
> > there are some places that PM core can disable direct-complete. For
> > instance, system hibernation or when codec has subordinates like LEDs.
>
> Hmm. This sounds rather like the approach using the direct-complete
> isn't well suited for the purpose? The increasing number of
> regression reports worries me.
Direct-complete works fine on HDA controller but so far not so on HDA codec.
I think the main reason is that the codec doesn't have the middle
layer to handle the detail, while HDA controller has PCI bus to deal
with them.
>
> > So if a device is prepared for direct-complete but PM core still calls
> > codec's suspend or freeze callback, resume the device to keep PM
> > operations balanced.
>
> I find the ping-pong of the resume/suspend there a bit odd. It's no
> refcount management but it invokes the real resume there, which is
> involved with lots of operations.
Yes. I'll find a better approach to address this.
>
> Can we rather skip the hda_codec_suspend() call instead (while
> changing dev->power.power_state)?
Maybe we can revert the most of the commit, and just leave
hda_codec_pm_complete(), which is the most relevant part of the patch.
Let me test a bit and send a new patch. Let me know if you don't like
this approach.
A question a bit unrelated to the discussion - how does
snd_hdac_power_up_pm() work for concurrent resume?
It can work for recursive call, but what if there are concurrent
resume request, but pm_runtime_get_sync() is still running?
The second call may access the codec which hasn't completed resume.
Kai-Heng
>
>
> thanks,
>
> Takashi
>
> > Reported-by: Kenneth R. Crudup <kenny@panix.com>
> > Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> > ---
> > sound/pci/hda/hda_codec.c | 6 ++++++
> > 1 file changed, 6 insertions(+)
> >
> > diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
> > index 687216e74526..0afbced979df 100644
> > --- a/sound/pci/hda/hda_codec.c
> > +++ b/sound/pci/hda/hda_codec.c
> > @@ -2997,6 +2997,9 @@ static void hda_codec_pm_complete(struct device *dev)
> >
> > static int hda_codec_pm_suspend(struct device *dev)
> > {
> > + if (pm_runtime_status_suspended(dev))
> > + pm_runtime_resume(dev);
> > +
> > dev->power.power_state = PMSG_SUSPEND;
> > return hda_codec_suspend(dev);
> > }
> > @@ -3009,6 +3012,9 @@ static int hda_codec_pm_resume(struct device *dev)
> >
> > static int hda_codec_pm_freeze(struct device *dev)
> > {
> > + if (pm_runtime_status_suspended(dev))
> > + pm_runtime_resume(dev);
> > +
> > dev->power.power_state = PMSG_FREEZE;
> > return hda_codec_suspend(dev);
> > }
> > --
> > 2.29.2
> >
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-01-18 17:33 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-01-18 13:09 [PATCH] ALSA: hda: Balance runtime/system PM if direct-complete is disabled Kai-Heng Feng
2021-01-18 13:09 ` Kai-Heng Feng
2021-01-18 13:21 ` Takashi Iwai
2021-01-18 13:21 ` Takashi Iwai
2021-01-18 17:27 ` Kai-Heng Feng
2021-01-18 17:27 ` Kai-Heng Feng
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