drm/i915: Keep a global seqno per-engine
authorChris Wilson <chris@chris-wilson.co.uk>
Thu, 23 Feb 2017 07:44:08 +0000 (07:44 +0000)
committerChris Wilson <chris@chris-wilson.co.uk>
Thu, 23 Feb 2017 14:49:26 +0000 (14:49 +0000)
commit9b6586ae9f6bf2115cf414d6004bbe69a4255692
treecbe39240c3a2b743694d0b8397a43854f838a41f
parent309663ab7b4f0de1540aff212fd067e3dd92acf3
drm/i915: Keep a global seqno per-engine

Replace the global device seqno with one for each engine, and account
for in-flight seqno on each separately. This is consistent with
dma-fence as each timeline has separate fence-contexts for each engine
and a seqno is only ordered within a fence-context (i.e.  seqno do not
need to be ordered wrt to other engines, just ordered within a single
engine). This is required to enable request rewinding for preemption on
individual engines (we have to rewind the global seqno to avoid
overflow, and we do not have to rewind all engines just to preempt one.)

v2: Rename active_seqno to inflight_seqnos to more clearly indicate that
it is a counter and not equivalent to the existing seqno. Update
functions that operated on active_seqno similarly.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170223074422.4125-3-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/i915_debugfs.c
drivers/gpu/drm/i915/i915_gem_request.c
drivers/gpu/drm/i915/i915_gem_request.h
drivers/gpu/drm/i915/i915_gem_timeline.h
drivers/gpu/drm/i915/intel_breadcrumbs.c
drivers/gpu/drm/i915/intel_engine_cs.c
drivers/gpu/drm/i915/intel_ringbuffer.h