tree 28090820b11f20776b4c12ff6c9fb1cf2eedee93
parent 619a341b78f17fb86d92e89c04612676cd05e26f
author David Henningsson <david.henningsson@canonical.com> 1336122355 +0200
committer Takashi Iwai <tiwai@suse.de> 1336551726 +0200

ALSA: HDA: Lessen CPU usage when waiting for chip to respond

When an IRQ for some reason gets lost, we wait up to a second using
udelay, which is CPU intensive. This patch improves the situation by
waiting about 30 ms in the CPU intensive mode, then stepping down to
using msleep(2) instead. In essence, we trade some granularity in
exchange for less CPU consumption when the waiting time is a bit longer.

As a result, PulseAudio should no longer be killed by the kernel
for taking up to much RT-prio CPU time. At least not for *this* reason.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Tested-by: Arun Raghavan <arun.raghavan@collabora.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>