Re: [Intel-gfx] [PATCH v3] drm/i915: Move CSB MMIO reads out of the execlists lock

2016-03-21 Thread Daniel Vetter
On Thu, Mar 17, 2016 at 04:30:47PM +, Tvrtko Ursulin wrote: > > On 17/03/16 13:14, Chris Wilson wrote: > >On Thu, Mar 17, 2016 at 12:59:46PM +, Tvrtko Ursulin wrote: > >>From: Tvrtko Ursulin > >> > >>By reading the CSB (slow MMIO accesses) into a temporary local > >>buffer we can decrease

[Intel-gfx] [PATCH v3] drm/i915: Move CSB MMIO reads out of the execlists lock

2016-03-19 Thread Tvrtko Ursulin
From: Tvrtko Ursulin By reading the CSB (slow MMIO accesses) into a temporary local buffer we can decrease the duration of holding the execlist lock. Main advantage is that during heavy batch buffer submission we reduce the execlist lock contention, which should decrease the latency and CPU usag

Re: [Intel-gfx] [PATCH v3] drm/i915: Move CSB MMIO reads out of the execlists lock

2016-03-19 Thread Tvrtko Ursulin
On 17/03/16 13:14, Chris Wilson wrote: On Thu, Mar 17, 2016 at 12:59:46PM +, Tvrtko Ursulin wrote: From: Tvrtko Ursulin By reading the CSB (slow MMIO accesses) into a temporary local buffer we can decrease the duration of holding the execlist lock. Main advantage is that during heavy bat

Re: [Intel-gfx] [PATCH v3] drm/i915: Move CSB MMIO reads out of the execlists lock

2016-03-19 Thread Chris Wilson
On Thu, Mar 17, 2016 at 12:59:46PM +, Tvrtko Ursulin wrote: > From: Tvrtko Ursulin > > By reading the CSB (slow MMIO accesses) into a temporary local > buffer we can decrease the duration of holding the execlist > lock. > > Main advantage is that during heavy batch buffer submission we > red