[Intel-gfx] [PATCH] drm/i915: Reinstate order of operations in {intel, logical}_ring_begin()

[Chris Wilson]

On Tue, Jun 16, 2015 at 02:18:55PM +0200, Daniel Vetter wrote:
> Maybe someone should look at per-buffer locks before trying to split up
> the low-level hw locks ;-)

Per-vm then per-buffer. Adding more locked operations to execbuf is
scary though, with some workloads perf highlights the cost of the atomic
for an uncontested mutex as being where the majority of the time is
going.

At this point I am questing perf, but it is the last remaining locked
instruction in that path...
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre