On 9 Oct 2013, at 20:42, Hans de Goede wrote:
> Now that we no longer have MIN_REARM_TIMER_NS a bug in the audio subsys has
> clearly shown it self by trying to make a timer fire every nano second.
>
> Note we have a similar problem in 1.6, 1.5 and older but there
> MIN_REARM_TIMER_NS limits the wakeups caused by audio being active to
> 4000 times / second. This still causes a host cpu load of 50 % for simply
> playing audio, where as with this patch git master is at 13%, so we should
> backport this to 1.5 and 1.6 too.
>
> Note this will not apply to 1.5 and 1.6 as is.
>
> Cc: qemu-sta...@nongnu.org
> Signed-off-by: Hans de Goede <hdego...@redhat.com>
> ---
> audio/audio.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/audio/audio.c b/audio/audio.c
> index af4cdf6..b3db679 100644
> --- a/audio/audio.c
> +++ b/audio/audio.c
> @@ -1124,7 +1124,8 @@ static int audio_is_timer_needed (void)
> static void audio_reset_timer (AudioState *s)
> {
> if (audio_is_timer_needed ()) {
> - timer_mod (s->ts, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 1);
> + timer_mod (s->ts,
> + qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + conf.period.ticks);
This assumes conf.period.ticks is in nanoseconds. That seems wrong.
Suggest multiplying by SCALE_US or SCALE_MS.
Alex
> }
> else {
> timer_del (s->ts);
> --
> 1.8.3.1
>
>
>
--
Alex Bligh
