Commit 2db2be56 authored by Chris Down's avatar Chris Down Committed by Takashi Iwai
Browse files

ALSA: usb-audio: Rate limit usb_set_interface error reporting 



When an error occurs during USB disconnection sometimes things can go
wrong as endpoint_set_interface may end up being called repeatedly. For
example:

% dmesg --notime | grep 'usb 3-7.1.4' | sort | uniq -c | head -2
   3069 usb 3-7.1.4: 1:1: usb_set_interface failed (-19)
    908 usb 3-7.1.4: 1:1: usb_set_interface failed (-71)

In my case, there sometimes are hundreds of these usb_set_interface
failure messages a second when I disconnect the hub that has my USB
audio device.

These messages can take a huge amount of the kmsg ringbuffer and don't
provide any extra information over the previous ones, so ratelimit them.

Signed-off-by: default avatarChris Down <chris@chrisdown.name>
Link: https://lore.kernel.org/r/ZEKf8UYBYa1h4JWR@chrisdown.name


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 4d421eeb

sound/usb/endpoint.c

+3 −2
Original line number Diff line number Diff line
@@ -916,7 +916,8 @@ static int endpoint_set_interface(struct snd_usb_audio *chip, 
		      ep->iface, altset, ep->ep_num);

	err = usb_set_interface(chip->dev, ep->iface, altset);

	if (err < 0) {

		usb_audio_err(chip, "%d:%d: usb_set_interface failed (%d)\n",

		usb_audio_err_ratelimited(

			chip, "%d:%d: usb_set_interface failed (%d)\n",

			ep->iface, altset, err);

		return err;

	}

sound/usb/usbaudio.h

+2 −0
Original line number Diff line number Diff line
@@ -67,6 +67,8 @@ struct snd_usb_audio { 


#define usb_audio_err(chip, fmt, args...) \

	dev_err(&(chip)->dev->dev, fmt, ##args)

#define usb_audio_err_ratelimited(chip, fmt, args...) \

	dev_err_ratelimited(&(chip)->dev->dev, fmt, ##args)

#define usb_audio_warn(chip, fmt, args...) \

	dev_warn(&(chip)->dev->dev, fmt, ##args)

#define usb_audio_info(chip, fmt, args...) \