drm: Use a little stash on the stack to avoid kmalloc in most DRM ioctls.
authorEric Anholt <eric@anholt.net>
Fri, 20 Mar 2009 01:56:14 +0000 (18:56 -0700)
committerDave Airlie <airlied@redhat.com>
Sun, 29 Mar 2009 08:31:37 +0000 (18:31 +1000)
commit955a23eb3cfc773e71b05bb7a0a0938a9e1b2568
tree7a9124ddf103ef1f6337484bb5e5ae51c9c288a6
parentaf7ae351ad63a137ece86740dbe3f181d09d810f
drm: Use a little stash on the stack to avoid kmalloc in most DRM ioctls.

The kmalloc was taking up about 1.5% of the CPU on an ioctl-heavy workload
(x11perf -aa10text on 965).  Initial results look like they have a
corresponding improvement in performance for aa10text, but more numbers might
not hurt.

Thanks to ajax for pointing out this performance regression I'd introduced
back in 2007.

[airlied: well I introduced it sneakily inside Eric's patch]

Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
drivers/gpu/drm/drm_drv.c