From 2a1d775201081c400d7e60ceb8e5ac887d11b1f7 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 26 Jul 2016 12:01:51 +0100 Subject: [PATCH] drm/i915: Prefer list_first_entry_or_null list_first_entry_or_null() can generate better code than using if (!list_empty()) {ptr = list_first_entry()) ..., so put it to use. Signed-off-by: Chris Wilson Link: http://patchwork.freedesktop.org/patch/msgid/1469432687-22756-3-git-send-email-chris@chris-wilson.co.uk Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/1469530913-17180-2-git-send-email-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_gtt.c | 12 +++++------- drivers/gpu/drm/i915/i915_gem_request.c | 8 +++----- drivers/gpu/drm/i915/i915_gem_shrinker.c | 9 +++++---- 3 files changed, 13 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 30da543e1bdf..38e7d992a20d 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -2736,13 +2736,11 @@ static void i915_gtt_color_adjust(struct drm_mm_node *node, if (node->color != color) *start += 4096; - if (!list_empty(&node->node_list)) { - node = list_entry(node->node_list.next, - struct drm_mm_node, - node_list); - if (node->allocated && node->color != color) - *end -= 4096; - } + node = list_first_entry_or_null(&node->node_list, + struct drm_mm_node, + node_list); + if (node && node->allocated && node->color != color) + *end -= 4096; } static int i915_gem_setup_global_gtt(struct drm_device *dev, diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index 60a3a343b3a8..49396b895a36 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -317,12 +317,10 @@ __i915_gem_request_alloc(struct intel_engine_cs *engine, return ret; /* Move the oldest request to the slab-cache (if not in use!) */ - if (!list_empty(&engine->request_list)) { - req = list_first_entry(&engine->request_list, + req = list_first_entry_or_null(&engine->request_list, typeof(*req), list); - if (i915_gem_request_completed(req)) - i915_gem_request_retire(req); - } + if (req && i915_gem_request_completed(req)) + i915_gem_request_retire(req); req = kmem_cache_zalloc(dev_priv->requests, GFP_KERNEL); if (!req) diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c index afaa2597e35e..5d4772c146b1 100644 --- a/drivers/gpu/drm/i915/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c @@ -163,17 +163,18 @@ i915_gem_shrink(struct drm_i915_private *dev_priv, */ for (phase = phases; phase->list; phase++) { struct list_head still_in_list; + struct drm_i915_gem_object *obj; if ((flags & phase->bit) == 0) continue; INIT_LIST_HEAD(&still_in_list); - while (count < target && !list_empty(phase->list)) { - struct drm_i915_gem_object *obj; + while (count < target && + (obj = list_first_entry_or_null(phase->list, + typeof(*obj), + global_list))) { struct i915_vma *vma, *v; - obj = list_first_entry(phase->list, - typeof(*obj), global_list); list_move_tail(&obj->global_list, &still_in_list); if (flags & I915_SHRINK_PURGEABLE && -- 2.20.1