ALSA: hrtimer: handle delayed timer interrupts
authorClemens Ladisch <clemens@ladisch.de>
Thu, 10 Feb 2011 15:15:44 +0000 (16:15 +0100)
committerTakashi Iwai <tiwai@suse.de>
Thu, 10 Feb 2011 17:53:29 +0000 (18:53 +0100)
commitb1d4f7f4bdcf9915c41ff8cfc4425c84dabb1fde
tree092e1575eb7c098670ebebd568566067e11a8c32
parenta6c47a85b8e7e4a8c47394607c5e5c43224b0892
ALSA: hrtimer: handle delayed timer interrupts

If a timer interrupt was delayed too much, hrtimer_forward_now() will
forward the timer expiry more than once.  When this happens, the
additional number of elapsed ALSA timer ticks must be passed to
snd_timer_interrupt() to prevent the ALSA timer from falling behind.

This mostly fixes MIDI slowdown problems on highly-loaded systems with
badly behaved interrupt handlers.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-and-tested-by: Arthur Marsh <arthur.marsh@internode.on.net>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/core/hrtimer.c