From b1151cd2ffc821a09130f87c2a266b2bfe7b0822 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Fri, 8 May 2020 14:53:47 -0700 Subject: [PATCH] freedreno: Avoid duplicate BO relocs in FD_RINGBUFFER_OBJECTs. For the piglit drawoverhead case, 5/18 of the objects' relocs were duplicated. We can dedupe them at object create time (since objects are long-lived) and avoid repeated relocation work at emit time. nohw drawoverhead program statechange throughput 2.34082% +/- 0.645832% (n=10). Part-of: --- src/freedreno/drm/msm_ringbuffer_sp.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/src/freedreno/drm/msm_ringbuffer_sp.c b/src/freedreno/drm/msm_ringbuffer_sp.c index 6bab90b..869c41d 100644 --- a/src/freedreno/drm/msm_ringbuffer_sp.c +++ b/src/freedreno/drm/msm_ringbuffer_sp.c @@ -385,9 +385,23 @@ msm_ringbuffer_sp_emit_reloc(struct fd_ringbuffer *ring, struct fd_pipe *pipe; if (ring->flags & _FD_RINGBUFFER_OBJECT) { - unsigned idx = APPEND(&msm_ring->u, reloc_bos); - - msm_ring->u.reloc_bos[idx] = fd_bo_ref(reloc->bo); + /* Avoid emitting duplicate BO references into the list. Ringbuffer + * objects are long-lived, so this saves ongoing work at draw time in + * exchange for a bit at context setup/first draw. And the number of + * relocs per ringbuffer object is fairly small, so the O(n^2) doesn't + * hurt much. + */ + bool found = false; + for (int i = 0; i < msm_ring->u.nr_reloc_bos; i++) { + if (msm_ring->u.reloc_bos[i] == reloc->bo) { + found = true; + break; + } + } + if (!found) { + unsigned idx = APPEND(&msm_ring->u, reloc_bos); + msm_ring->u.reloc_bos[idx] = fd_bo_ref(reloc->bo); + } pipe = msm_ring->u.pipe; } else { -- 2.7.4