kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-14 05:55:17 +00:00
Code Issues Releases Packages Activity

drm/i915: Make for_each_engine_masked() more compact and quicker

Browse source 
Rather than walk the full array of engines checking whether each is in
the mask in turn, we can use the mask to jump to the right engines. This
should quicker for a sparse array of engines or mask, whilst generating
smaller code:

   text	   data	    bss	    dec	    hex	filename
1251010	   4579	    800	1256389	 132bc5	drivers/gpu/drm/i915/i915.ko
1250530	   4579	    800	1255909	 1329e5	drivers/gpu/drm/i915/i915.ko

The downside is that we have to pass in a temporary, alas no C99
iterators yet.

[P.S. Joonas doesn't like having to pass extra temporaries into the
macro, and even less that I called them tmp. As yet, we haven't found a
macro that avoids passing in a temporary that is smaller. We probably
will get C99 iterators first!]

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160827075401.16470-2-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2016-08-27 08:54:01 +01:00
commit bafb0fced9
5 changed files with 21 additions and 12 deletions
Download patch file Download diff file Expand all files Collapse all files