From a5065eb6da55b226661456e6a7435f605df98111 Mon Sep 17 00:00:00 2001 From: Tim Gardner <tim.gardner@canonical.com> Date: Wed, 9 Apr 2014 11:30:44 -0600 Subject: [PATCH] ALSA: usb-audio: Suppress repetitive debug messages from retire_playback_urb() BugLink: http://bugs.launchpad.net/bugs/1305133 Malfunctioning or slow devices can cause a flood of dmesg SPAM. I've ignored checkpatch.pl complaints about the use of printk_ratelimit() in favour of prior art in sound/usb/pcm.c. WARNING: Prefer printk_ratelimited or pr_<level>_ratelimited to printk_ratelimit + if (printk_ratelimit() && Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: Eldad Zack <eldad@fogrefinery.com> Cc: Daniel Mack <zonque@gmail.com> Cc: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> --- 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 49de5c1284f6..131336d40492 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -1501,7 +1501,8 @@ 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 (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2) + if (printk_ratelimit() && + abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2) dev_dbg(&subs->dev->dev, "delay: estimated %d, actual %d\n", est_delay, subs->last_delay);