[Intel-gfx] [PATCH] drm: Aggressively disable vblanks

[Jesse Barnes]

On Mon, 20 Dec 2010 22:55:46 -0500
Andrew Lutomirski <luto at mit.edu> wrote:

> On Mon, Dec 20, 2010 at 10:47 PM, Keith Packard <keithp at keithp.com> wrote:
> > On Mon, 20 Dec 2010 22:34:12 -0500, Andrew Lutomirski <luto at mit.edu> wrote:
> >
> >> But five seconds is a *long* time, and anything short enough that the
> >> interrupt actually gets turned off in normal use risks the same race.
> >
> > Right, so eliminating any race seems like the basic requirement. Can
> > that be done?
> 
> I'll give it a shot.
> 
> Do you know if there's an existing tool to call drm_wait_vblank from
> userspace for testing?  I know approximately nothing about libdrm or
> any userspace graphics stuff whatsoever.

Yeah, libdrm has a test program called vbltest; it should do what you
need.

-- 
Jesse Barnes, Intel Open Source Technology Center