On Thu, Sep 08, 2016 at 04:12:55PM +0100, Tvrtko Ursulin wrote: > From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> > > This removes the usage of intel_ring_emit in favour of > directly writing to the ring buffer. I have the same patch! But I called it out, for historical reasons. Oh, except mine uses out[0]...out[N] because gcc prefers that over *out++ = ... > intel_ring_emit was preventing the compiler for optimising > fetch and increment of the current ring buffer pointer and > therefore generating very verbose code for every write. > > It had no useful purpose since all ringbuffer operations > are started and ended with intel_ring_begin and > intel_ring_advance respectively, with no bail out in the > middle possible, so it is fine to increment the tail in > intel_ring_begin and let the code manage the pointer > itself. > > Useless instruction removal amounts to approximately > 2384 bytes of saved text on my build. > > Not sure if this has any measurable performance > implications but executing a ton of useless instructions > on fast paths cannot be good. It does show up in perf. > Patch is not fully polished, but it compiles and runs > on Gen9 at least. > > Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> > --- > drivers/gpu/drm/i915/i915_gem_context.c | 62 ++-- > drivers/gpu/drm/i915/i915_gem_execbuffer.c | 27 +- > drivers/gpu/drm/i915/i915_gem_gtt.c | 57 ++-- > drivers/gpu/drm/i915/intel_display.c | 113 ++++--- > drivers/gpu/drm/i915/intel_lrc.c | 223 +++++++------- > drivers/gpu/drm/i915/intel_mocs.c | 43 +-- > drivers/gpu/drm/i915/intel_overlay.c | 69 ++--- > drivers/gpu/drm/i915/intel_ringbuffer.c | 480 +++++++++++++++-------------- > drivers/gpu/drm/i915/intel_ringbuffer.h | 19 +- > 9 files changed, 555 insertions(+), 538 deletions(-) Hmm, mine is bigger. drivers/gpu/drm/i915/i915_gem_context.c | 85 ++-- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 37 +- drivers/gpu/drm/i915/i915_gem_gtt.c | 62 +-- drivers/gpu/drm/i915/i915_gem_request.c | 135 ++++- drivers/gpu/drm/i915/i915_gem_request.h | 2 + drivers/gpu/drm/i915/intel_display.c | 133 +++-- drivers/gpu/drm/i915/intel_lrc.c | 188 ++++--- drivers/gpu/drm/i915/intel_lrc.h | 2 - drivers/gpu/drm/i915/intel_mocs.c | 50 +- drivers/gpu/drm/i915/intel_overlay.c | 77 ++- drivers/gpu/drm/i915/intel_ringbuffer.c | 762 ++++++++++++----------------- drivers/gpu/drm/i915/intel_ringbuffer.h | 36 +- 12 files changed, 721 insertions(+), 848 deletions(-) (this includes moving the intel_ring_begin to i915_gem_request) plus an ealier drivers/gpu/drm/i915/i915_gem_request.c | 26 ++--- drivers/gpu/drm/i915/intel_lrc.c | 121 ++++++++--------------- drivers/gpu/drm/i915/intel_ringbuffer.c | 168 +++++++++++--------------------- drivers/gpu/drm/i915/intel_ringbuffer.h | 10 +- 4 files changed, 112 insertions(+), 213 deletions(-) since I wanted parts of it for emitting timelines. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
