Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4]

Ingo Molnar
2004-10-29T17:19:09Z

* Ingo Molnar <mingo@elte.hu> wrote:

> > > let me try some more hacks to make this a little bit safer.
> >
> > hehe, it even booted for me [kinda]. will build the one where you got
> > xmms to run. but i will sure as hell hit "get new emails" during the
> > build more than once ;)
>
> indeed - i'm preparing 5.0.12 with a better way to do this. (the trick
> is to allow the BKL to 'underflow' - this way ALSA can be kept largely
> unmodified.)

ok, i've uploaded -V0.5.12 which has this BKL trick. I hope i got the
ALSA ioctls right: the ones that go outside the BKL for now are the
pcm_native playback/capture ones, and rawmidi's ioctl. All the others
are still BKL users. To recap, it's these ioctls that matter:

5971 ioctl(7, 0x4143, 0x446b7d3c) = 0
5971 ioctl(7, 0x4140, 0x446b7d3c) = 0
5971 ioctl(7, 0x4142, 0x446b7d3c) = 0

which ones are these? Look at the patch for how to change a .ioctl one
to .ioctl_nobkl (lame solution ...). So if your setup uses any other
ioctl (sndctl perhaps?) then you should change that one to nobkl too.

Ingo