2.6.35-longterm review patch. If anyone has any objections, please let me know.
------------------ From: Clemens Ladisch <[email protected]> commit b1d4f7f4bdcf9915c41ff8cfc4425c84dabb1fde upstream. 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 <[email protected]> Signed-off-by: Andi Kleen <[email protected]> Reported-and-tested-by: Arthur Marsh <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- sound/core/hrtimer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) Index: linux-2.6.35.y/sound/core/hrtimer.c =================================================================== --- linux-2.6.35.y.orig/sound/core/hrtimer.c 2011-03-29 22:51:50.260437129 -0700 +++ linux-2.6.35.y/sound/core/hrtimer.c 2011-03-29 23:02:59.176321246 -0700 @@ -45,12 +45,13 @@ { struct snd_hrtimer *stime = container_of(hrt, struct snd_hrtimer, hrt); struct snd_timer *t = stime->timer; + unsigned long oruns; if (!atomic_read(&stime->running)) return HRTIMER_NORESTART; - hrtimer_forward_now(hrt, ns_to_ktime(t->sticks * resolution)); - snd_timer_interrupt(stime->timer, t->sticks); + oruns = hrtimer_forward_now(hrt, ns_to_ktime(t->sticks * resolution)); + snd_timer_interrupt(stime->timer, t->sticks * oruns); if (!atomic_read(&stime->running)) return HRTIMER_NORESTART; _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
