From: Ioan-Adrian Ratiu Date: Wed, 4 Jan 2017 22:37:47 +0000 (+0200) Subject: ALSA: usb-audio: test EP_FLAG_RUNNING at urb completion X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=13a6c8328e6056932dc680e447d4c5e8ad9add17;p=linux-beck.git ALSA: usb-audio: test EP_FLAG_RUNNING at urb completion Testing EP_FLAG_RUNNING in snd_complete_urb() before running the completion logic allows us to save a few cpu cycles by returning early, skipping the pending urb in case the stream was stopped; the stop logic handles the urb and sets the completion callbacks to NULL. Signed-off-by: Ioan-Adrian Ratiu Signed-off-by: Takashi Iwai --- diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index 2f0ea70a998c..c90607ebe155 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -384,6 +384,9 @@ static void snd_complete_urb(struct urb *urb) if (unlikely(atomic_read(&ep->chip->shutdown))) goto exit_clear; + if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) + goto exit_clear; + if (usb_pipeout(ep->pipe)) { retire_outbound_urb(ep, ctx); /* can be stopped during retire callback */