[Intel-gfx] [PATCH] drm/i915: Stop CRC gathering when the ctl file is closed

[Ville Syrjälä]

On Mon, Oct 21, 2013 at 06:17:30PM +0200, Daniel Vetter wrote:
> On Mon, Oct 21, 2013 at 6:01 PM,  <ville.syrjala at linux.intel.com> wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >
> > If no one is looking at the CRCs, stop gathering them.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> As discussed on irc this prevents fools like me from wreaking havoc
> directly with the cli, at least if you still want to interactively
> test stuff easily (background processes and all would work around
> this). Imo it's better to disable (and maybe re-enable) the CRC stuff
> when we disable/enable the pipe.

I would still suggest using exec for keeping the file open.

Especially if we go for the auto re-enable, since then we'd
essientially never turn off the crc capture once it's started
unless someone explicitly writes to the ctl file. We'd just pause
it while the pipe is off.

Also I would assume we want to avoid full modesets in the future
if possible, so relying on that doesn't feel very robust to me.

-- 
Ville Syrjälä
Intel OTC