From 32fc0c896e0dfd06617c12beda1ccacedf69fb4a Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 31 Aug 2011 23:21:54 +0100 Subject: sna/gen6: Prefer the BLT ring, except for copies on behalf of DRI As demonstrated by the all-important trap300, using the BLT is 2x faster than the RENDER ring for the simple case of solid fills. (Though note that performing the relocations costs 3x as much CPU for 2x GPU performance.) One case that may regress from this change is copywinpix which should benefit from the batching in the RENDER commands, and might warrant revisiting in the future (with realistic and synthetic benchmarks in hand!) However, due to the forced stall when switching rings, we still want to perform RENDER copies on behalf of DRI clients and before page-flips. Checking against cairo-perf-trace indicated no major impact -- I had worried that setting the BLT flag for some clears might have had a knock-on effect causing too many operations that could be pipelined on the RENDER ring to be sent to the BLT ring instead. Reported-by: Michael Larabel Signed-off-by: Chris Wilson --- src/sna/gen6_render.c | 10 ++++++---- src/sna/sna_dri.c | 16 ++++++++++++++++ 2 files changed, 22 insertions(+), 4 deletions(-) diff --git a/src/sna/gen6_render.c b/src/sna/gen6_render.c index 5641b3ca..eb67fc67 100644 --- a/src/sna/gen6_render.c +++ b/src/sna/gen6_render.c @@ -2307,7 +2307,8 @@ gen6_render_copy_boxes(struct sna *sna, uint8_t alu, __FUNCTION__, src_dx, src_dy, dst_dx, dst_dy, n, alu, src_bo == dst_bo)); - if (sna->kgem.mode == KGEM_BLT && + /* XXX benchmark me! */ + if (sna->kgem.mode != KGEM_RENDER && sna_blt_compare_depth(&src->drawable, &dst->drawable) && sna_blt_copy_boxes(sna, alu, src_bo, src_dx, src_dy, @@ -2464,7 +2465,8 @@ gen6_render_copy(struct sna *sna, uint8_t alu, src->drawable.width, src->drawable.height, dst->drawable.width, dst->drawable.height)); - if (sna->kgem.mode == KGEM_BLT && + /* XXX benchmark me! */ + if (sna->kgem.mode != KGEM_RENDER && sna_blt_compare_depth(&src->drawable, &dst->drawable) && sna_blt_copy(sna, alu, src_bo, dst_bo, @@ -2577,7 +2579,7 @@ gen6_render_fill_boxes(struct sna *sna, return FALSE; } - if (sna->kgem.mode == KGEM_BLT || + if (sna->kgem.mode != KGEM_RENDER || dst->drawable.width > 8192 || dst->drawable.height > 8192 || !gen6_check_dst_format(format)) { @@ -2734,7 +2736,7 @@ gen6_render_fill(struct sna *sna, uint8_t alu, op); #endif - if (sna->kgem.mode == KGEM_BLT && + if (sna->kgem.mode != KGEM_RENDER && sna_blt_fill(sna, alu, dst_bo, dst->drawable.bitsPerPixel, color, diff --git a/src/sna/sna_dri.c b/src/sna/sna_dri.c index 0a01f8af..f4049f19 100644 --- a/src/sna/sna_dri.c +++ b/src/sna/sna_dri.c @@ -461,6 +461,22 @@ sna_dri_copy(struct sna *sna, DrawablePtr draw, RegionPtr region, get_drawable_deltas(draw, dst, &dx, &dy); } + if (sna->kgem.gen >= 60) { + /* Sandybridge introduced a separate ring which it uses to + * perform blits. Switching rendering between rings incurs + * a stall as we wait upon the old ring to finish and + * flush its render cache before we can proceed on with + * the operation on the new ring. + * + * As this buffer, we presume, has just been written to by + * the DRI client using the RENDER ring, we want to perform + * our operation on the same ring, and ideally on the same + * ring as we will flip from (which should be the RENDER ring + * as well). + */ + kgem_set_mode(&sna->kgem, KGEM_RENDER); + } + if (region) { boxes = REGION_RECTS(region); n = REGION_NUM_RECTS(region); -- cgit v1.2.3