From 92d0b44872710c7a7ca893a0bb2cf5fc0f7d985f Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 22 Aug 2016 08:44:29 +0100 Subject: [PATCH] drm/i915: Stop marking the unaccessible scratch page as UC Since by design, if not entirely by practice, nothing is allowed to access the scratch page we use to background fill the VM, then we do not need to ensure that it is coherent between the CPU and GPU. set_pages_uc() does a stop_machine() after changing the PAT, and that significantly impacts upon context creation throughput. Signed-off-by: Chris Wilson Link: http://patchwork.freedesktop.org/patch/msgid/20160822074431.26872-1-chris@chris-wilson.co.uk Reviewed-by: Joonas Lahtinen --- drivers/gpu/drm/i915/i915_gem_gtt.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index b90fdcee992ac..b3cd9e21c8dae 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -422,16 +422,12 @@ static struct i915_page_scratch *alloc_scratch_page(struct drm_device *dev) return ERR_PTR(ret); } - set_pages_uc(px_page(sp), 1); - return sp; } static void free_scratch_page(struct drm_device *dev, struct i915_page_scratch *sp) { - set_pages_wb(px_page(sp), 1); - cleanup_px(dev, sp); kfree(sp); } -- 2.39.5