From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from youngberry.canonical.com ([91.189.89.112]:47090 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753840AbaFTPVM (ORCPT ); Fri, 20 Jun 2014 11:21:12 -0400 Message-ID: <53A4515C.8090103@canonical.com> Date: Fri, 20 Jun 2014 11:21:00 -0400 From: Joseph Salisbury MIME-Version: 1.0 To: Ben Hutchings CC: greg@kroah.com, kamal.mostafa@canonical.com, luis.henriques@canonical.com, jslaby@suse.cz, clm@fb.com, jbacik@fb.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: Re: [v3.10.y][v3.11.y][v3.12.y][v3.13.y][v3.14.y][PATCH 1/1][V2] ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined References: <1403142759.23472.28.camel@deadeye.wl.decadent.org.uk> In-Reply-To: <1403142759.23472.28.camel@deadeye.wl.decadent.org.uk> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 06/18/2014 09:52 PM, Ben Hutchings wrote: > On Wed, 2014-06-18 at 14:32 -0400, Joseph Salisbury wrote: >> From: Sander Eikelenboom >> >> 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 >> Signed-off-by: Takashi Iwai >> (backported from commit b7a7723513dc89f83d6df13206df55d4dc26e825) >> Signed-off-by: Joseph Salisbury > It looks like you have combined the commit identified here with the > preceding: > > commit a5065eb6da55b226661456e6a7435f605df98111 > Author: Tim Gardner > Date: Wed Apr 9 11:30:44 2014 -0600 > > ALSA: usb-audio: Suppress repetitive debug messages from retire_playback_urb() > > They should not be squashed together like this. > > Ben. > >> --- >> sound/usb/pcm.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c >> index ca3256d..ede4b92 100644 >> --- a/sound/usb/pcm.c >> +++ b/sound/usb/pcm.c >> @@ -1488,7 +1488,8 @@ static void retire_playback_urb(struct snd_usb_substream *subs, >> * on two reads of a counter updated every ms. >> */ >> if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2) >> - snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n", >> + dev_dbg_ratelimited(&subs->dev->dev, >> + "delay: estimated %d, actual %d\n", >> est_delay, subs->last_delay); >> >> if (!subs->running) { Hi Ben, Thanks for the feedback. Do you think it's best to cherry-pick these two commits? If so, I'll do that and test. If it all works, I can send a request to stable to cherry pick the commits and revert my backport. Thanks, Joe