On 9 Oct 2013, at 19:28, Alex Bligh wrote:
>>
>> static void audio_reset_timer (AudioState *s)
>> {
>> if (audio_is_timer_needed ()) {
>> timer_mod (s->ts, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 1);
>> }
>> else {
>> timer_del (s->ts);
>> }
>> }
>>
>> static void audio_timer (void *opaque)
>> {
>> audio_run ("timer");
>> audio_reset_timer (opaque);
>> }
>>
>> Note how that is using a timer which expires every freaking nano second,
>> I think it is very likely that is the culprit.
>
> Indeed. I am hoping that it is not my automated perl conversion code that
> did that, because if it is, it may have broken other stuff :-/
>
> Thanks for finding this - let me see whether the bug existed before
> my automated changes commit.
I think this was broken prior to my changes. Here's audio/audio.c before
my changes:
static void audio_reset_timer (AudioState *s)
{
if (audio_is_timer_needed ()) {
qemu_mod_timer (s->ts, qemu_get_clock_ns (vm_clock) + 1);
}
else {
qemu_del_timer (s->ts);
}
}
Now qemu_get_clock_ns can only return something in nanoseconds, so it's
adding 1 nanosecond. This is thus either broken because:
1. ts->scale is in nanoseconds, in which case that timer expires in
one nano-second's time; or
2. ts->scale is not in nanoseconds, in which case nanosecond VM clock
is going to be a huge time in the future, and it's never going
to expire.
I wonder whether it's meant to be 1 millisecond or 1 microsecond?
Whatever, it looks like this is suitable for an individual patch to
audio/audio.c
--
Alex Bligh
