From 46b863325c2f58b564463c4d6e66ee0d4f2f3244 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 19 Mar 2018 12:35:28 +0000 Subject: [PATCH] drm/i915: Prefer memset64() when filling the iomap As the ringbuffer may exist inside stolen memory, our access to it may be via the GTT iomap. This implies we may only have WC access for which the conventional memset() substitution of rep stos performs very badly, so switch to the rep mov[dq] variants when available. Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Matthew Auld Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20180319123528.28249-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_ringbuffer.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 72d6167c519a..04d9d9a946a7 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1693,17 +1693,18 @@ u32 *intel_ring_begin(struct i915_request *rq, unsigned int num_dwords) need_wrap &= ~1; GEM_BUG_ON(need_wrap > ring->space); GEM_BUG_ON(ring->emit + need_wrap > ring->size); + GEM_BUG_ON(!IS_ALIGNED(need_wrap, sizeof(u64))); /* Fill the tail with MI_NOOP */ - memset(ring->vaddr + ring->emit, 0, need_wrap); - ring->emit = 0; + memset64(ring->vaddr + ring->emit, 0, need_wrap / sizeof(u64)); ring->space -= need_wrap; + ring->emit = 0; } GEM_BUG_ON(ring->emit > ring->size - bytes); GEM_BUG_ON(ring->space < bytes); cs = ring->vaddr + ring->emit; - GEM_DEBUG_EXEC(memset(cs, POISON_INUSE, bytes)); + GEM_DEBUG_EXEC(memset32(cs, POISON_INUSE, bytes / sizeof(*cs))); ring->emit += bytes; ring->space -= bytes;