From 7f5f95d8aca44661efb4c66d405c21ca703a8e44 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 10 Mar 2017 00:09:42 +0000 Subject: [PATCH] drm/i915: Move whole object to CPU domain for coherent shmem access If the object is coherent, we can simply update the cache domain on the whole object rather than calculate the before/after clflushes. The advantage is that we then get correct tracking of ellided flushes when changing coherency later. Testcase: igt/gem_pwrite_snooped Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/20170310000942.11661-1-chris@chris-wilson.co.uk Reviewed-by: Joonas Lahtinen --- drivers/gpu/drm/i915/i915_drv.h | 6 +++--- drivers/gpu/drm/i915/i915_gem.c | 45 +++++++++++++++++++++-------------------- 2 files changed, 26 insertions(+), 25 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 6a1c4319f86f..d11c96405a53 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3353,9 +3353,9 @@ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj, unsigned int *needs_clflush); int i915_gem_obj_prepare_shmem_write(struct drm_i915_gem_object *obj, unsigned int *needs_clflush); -#define CLFLUSH_BEFORE 0x1 -#define CLFLUSH_AFTER 0x2 -#define CLFLUSH_FLAGS (CLFLUSH_BEFORE | CLFLUSH_AFTER) +#define CLFLUSH_BEFORE BIT(0) +#define CLFLUSH_AFTER BIT(1) +#define CLFLUSH_FLAGS (CLFLUSH_BEFORE | CLFLUSH_AFTER) static inline void i915_gem_obj_finish_shmem_access(struct drm_i915_gem_object *obj) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index aca1eaddafb4..202bb850f260 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -788,6 +788,15 @@ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj, if (ret) return ret; + if (i915_gem_object_is_coherent(obj) || + !static_cpu_has(X86_FEATURE_CLFLUSH)) { + ret = i915_gem_object_set_to_cpu_domain(obj, false); + if (ret) + goto err_unpin; + else + goto out; + } + i915_gem_object_flush_gtt_write_domain(obj); /* If we're not in the cpu read domain, set ourself into the gtt @@ -796,16 +805,9 @@ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj, * anyway again before the next pread happens. */ if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) - *needs_clflush = !i915_gem_object_is_coherent(obj); - - if (*needs_clflush && !static_cpu_has(X86_FEATURE_CLFLUSH)) { - ret = i915_gem_object_set_to_cpu_domain(obj, false); - if (ret) - goto err_unpin; - - *needs_clflush = 0; - } + *needs_clflush = CLFLUSH_BEFORE; +out: /* return with the pages pinned */ return 0; @@ -838,6 +840,15 @@ int i915_gem_obj_prepare_shmem_write(struct drm_i915_gem_object *obj, if (ret) return ret; + if (i915_gem_object_is_coherent(obj) || + !static_cpu_has(X86_FEATURE_CLFLUSH)) { + ret = i915_gem_object_set_to_cpu_domain(obj, true); + if (ret) + goto err_unpin; + else + goto out; + } + i915_gem_object_flush_gtt_write_domain(obj); /* If we're not in the cpu write domain, set ourself into the @@ -846,25 +857,15 @@ int i915_gem_obj_prepare_shmem_write(struct drm_i915_gem_object *obj, * right away and we therefore have to clflush anyway. */ if (obj->base.write_domain != I915_GEM_DOMAIN_CPU) - *needs_clflush |= cpu_write_needs_clflush(obj) << 1; + *needs_clflush |= CLFLUSH_AFTER; /* Same trick applies to invalidate partially written cachelines read * before writing. */ if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) - *needs_clflush |= !i915_gem_object_is_coherent(obj); - - if (*needs_clflush && !static_cpu_has(X86_FEATURE_CLFLUSH)) { - ret = i915_gem_object_set_to_cpu_domain(obj, true); - if (ret) - goto err_unpin; - - *needs_clflush = 0; - } - - if ((*needs_clflush & CLFLUSH_AFTER) == 0) - obj->cache_dirty = true; + *needs_clflush |= CLFLUSH_BEFORE; +out: intel_fb_obj_invalidate(obj, ORIGIN_CPU); obj->mm.dirty = true; /* return with the pages pinned */ -- 2.11.0