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

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

On Mon, Dec 20, 2010 at 10:47 PM, Keith Packard keithp@keithp.com wrote:

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On Mon, 20 Dec 2010 22:34:12 -0500, Andrew Lutomirski luto@mit.edu wrote:

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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.