[Trusty][SRU][PATCH 1/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Trusty][SRU][PATCH 1/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Joseph Salisbury]

From: Sander Eikelenboom <linux@eikelenboom.it>

BugLink: http://bugs.launchpad.net/bugs/1319457

This (widely used) construction:

if(printk_ratelimit())
	dev_dbg()

Causes the ratelimiting to spam the kernel log with the "callbacks suppressed"
message below, even while the dev_dbg it is supposed to rate limit wouldn't
print anything because DEBUG is not defined for this device.

[  533.803964] retire_playback_urb: 852 callbacks suppressed
[  538.807930] retire_playback_urb: 852 callbacks suppressed
[  543.811897] retire_playback_urb: 852 callbacks suppressed
[  548.815745] retire_playback_urb: 852 callbacks suppressed
[  553.819826] retire_playback_urb: 852 callbacks suppressed

So use dev_dbg_ratelimited() instead of this construction.

Signed-off-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
(backported from commit b7a7723513dc89f83d6df13206df55d4dc26e825)
Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>

---
 sound/usb/pcm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 7bfa7a1..ede4b92 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -1487,9 +1487,9 @@ static void retire_playback_urb(struct snd_usb_substream *subs,
 	 * The error should be lower than 2ms since the estimate relies
 	 * on two reads of a counter updated every ms.
 	 */
-	if (printk_ratelimit() &&
-	    abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
-		snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
+	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
+		dev_dbg_ratelimited(&subs->dev->dev,
+			"delay: estimated %d, actual %d\n",
 			est_delay, subs->last_delay);
 
 	if (!subs->running) {
-- 
1.9.1

[Trusty][SRU][PATCH 1/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Joseph Salisbury]

From: Sander Eikelenboom <linux@eikelenboom.it>

BugLink: http://bugs.launchpad.net/bugs/1319457

This (widely used) construction:

if(printk_ratelimit())
	dev_dbg()

Causes the ratelimiting to spam the kernel log with the "callbacks suppressed"
message below, even while the dev_dbg it is supposed to rate limit wouldn't
print anything because DEBUG is not defined for this device.

[  533.803964] retire_playback_urb: 852 callbacks suppressed
[  538.807930] retire_playback_urb: 852 callbacks suppressed
[  543.811897] retire_playback_urb: 852 callbacks suppressed
[  548.815745] retire_playback_urb: 852 callbacks suppressed
[  553.819826] retire_playback_urb: 852 callbacks suppressed

So use dev_dbg_ratelimited() instead of this construction.

Signed-off-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
(backported from commit b7a7723513dc89f83d6df13206df55d4dc26e825)
Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>

---
 sound/usb/pcm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 7bfa7a1..ede4b92 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -1487,9 +1487,9 @@ static void retire_playback_urb(struct snd_usb_substream *subs,
 	 * The error should be lower than 2ms since the estimate relies
 	 * on two reads of a counter updated every ms.
 	 */
-	if (printk_ratelimit() &&
-	    abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
-		snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
+	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
+		dev_dbg_ratelimited(&subs->dev->dev,
+			"delay: estimated %d, actual %d\n",
 			est_delay, subs->last_delay);
 
 	if (!subs->running) {
-- 
1.9.1

Re: [v3.13.y][SRU][PATCH 0/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Greg KH]

On Wed, Jun 18, 2014 at 01:14:05PM -0400, Joseph Salisbury wrote:
> BugLink: http://bugs.launchpad.net/bugs/1319457
> 
> Hello,
> 
> Please consider including upstream commit b7a77235 in the next v3.13.y release.  It was included upstream as of v3.15-rc5.  It has been tested and confirmed to resolve http://bugs.launchpad.net/bugs/1319457 .

Please get a good email client and wrap your lines :(

> commit b7a7723513dc89f83d6df13206df55d4dc26e825
> Author: Sander Eikelenboom <linux@eikelenboom.it>
> Date:   Fri May 2 15:09:27 2014 +0200
> 
>     ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined
> 
> 
> This commit does not apply cleanly to v3.13, so I performed a backport, which is in email 1/1. 

Any reason this shouldn't also be in 3.14-stable?

thanks,

greg k-h

Re: [v3.13.y][SRU][PATCH 0/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Joseph Salisbury]

On 06/18/2014 01:43 PM, Greg KH wrote:
> On Wed, Jun 18, 2014 at 01:14:05PM -0400, Joseph Salisbury wrote:
>> BugLink: http://bugs.launchpad.net/bugs/1319457
>>
>> Hello,
>>
>> Please consider including upstream commit b7a77235 in the next v3.13.y release.  It was included upstream as of v3.15-rc5.  It has been tested and confirmed to resolve http://bugs.launchpad.net/bugs/1319457 .
> Please get a good email client and wrap your lines :(
Hmm, not sure why git send-email did that, but I'll fix it.

>
>> commit b7a7723513dc89f83d6df13206df55d4dc26e825
>> Author: Sander Eikelenboom <linux@eikelenboom.it>
>> Date:   Fri May 2 15:09:27 2014 +0200
>>
>>     ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined
>>
>>
>> This commit does not apply cleanly to v3.13, so I performed a backport, which is in email 1/1. 
> Any reason this shouldn't also be in 3.14-stable?

Yes it should also be in 3.14 stable.  I'll send a v2 of the patch.

>
> thanks,
>
> greg k-h
Thanks for the feedback.

[v3.13.y][SRU][PATCH 0/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Joseph Salisbury]

BugLink: http://bugs.launchpad.net/bugs/1319457

Hello,

Please consider including upstream commit b7a77235 in the next v3.13.y release.  It was included upstream as of v3.15-rc5.  It has been tested and confirmed to resolve http://bugs.launchpad.net/bugs/1319457 .

commit b7a7723513dc89f83d6df13206df55d4dc26e825
Author: Sander Eikelenboom <linux@eikelenboom.it>
Date:   Fri May 2 15:09:27 2014 +0200

    ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined


This commit does not apply cleanly to v3.13, so I performed a backport, which is in email 1/1. 


Sander Eikelenboom (1):
  ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log
    while DEBUG not defined

 sound/usb/pcm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

-- 
1.9.1

[v3.13.y][SRU][PATCH 0/1] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined

[Joseph Salisbury]

BugLink: http://bugs.launchpad.net/bugs/1319457

Hello,

Please consider including upstream commit b7a77235 in the next v3.13.y release.  It was included upstream as of v3.15-rc5.  It has been tested and confirmed to resolve http://bugs.launchpad.net/bugs/1319457 .

commit b7a7723513dc89f83d6df13206df55d4dc26e825
Author: Sander Eikelenboom <linux@eikelenboom.it>
Date:   Fri May 2 15:09:27 2014 +0200

    ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined


This commit does not apply cleanly to v3.13, so I performed a backport, which is in email 1/1. 


Sander Eikelenboom (1):
  ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log
    while DEBUG not defined

 sound/usb/pcm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

-- 
1.9.1