From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: [PATCH 20/21] drm/i915: Use a slab for object allocation Date: Sat, 16 Apr 2011 10:17:44 +0100 Message-ID: <1302945465-32115-21-git-send-email-chris@chris-wilson.co.uk> References: <1302945465-32115-1-git-send-email-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from fireflyinternet.com (server109-228-6-236.live-servers.net [109.228.6.236]) by gabe.freedesktop.org (Postfix) with ESMTP id AD2479E935 for ; Sat, 16 Apr 2011 02:18:06 -0700 (PDT) In-Reply-To: <1302945465-32115-1-git-send-email-chris@chris-wilson.co.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org The primary purpose of this was to debug some use-after-free memory corruption that was causing an OOPS inside drm/i915. As it turned out the corruption was being caused elsewhere and i915.ko as a major user of many objects was being hit hardest. Indeed as we do frequent the generic kmalloc caches, dedicating one to ourselves (or at least naming one for us depending upon the core) aids debugging our own slab usage. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_dma.c | 3 +++ drivers/gpu/drm/i915/i915_drv.h | 2 ++ drivers/gpu/drm/i915/i915_gem.c | 12 +++++++++--- 3 files changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 3b69f38..d8269f3 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -2167,6 +2167,9 @@ int i915_driver_unload(struct drm_device *dev) destroy_workqueue(dev_priv->wq); + if (dev_priv->slab) + kmem_cache_destroy(dev_priv->slab); + pci_dev_put(dev_priv->bridge_dev); kfree(dev->dev_private); diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 30fbf3b..a8733ac 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -265,6 +265,8 @@ typedef struct drm_i915_private { const struct intel_device_info *info; + struct kmem_cache *slab; + int has_gem; int relative_constants_mode; diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index fe45f4e..f554273 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3785,7 +3785,7 @@ struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev, struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; - obj = kzalloc(sizeof(*obj), GFP_KERNEL); + obj = kmem_cache_alloc(dev_priv->slab, GFP_KERNEL | __GFP_ZERO); if (obj == NULL) return NULL; @@ -3860,7 +3860,7 @@ static void i915_gem_free_object_tail(struct drm_i915_gem_object *obj) kfree(obj->page_cpu_valid); kfree(obj->bit_17); - kfree(obj); + kmem_cache_free(dev_priv->slab, obj); } void i915_gem_free_object(struct drm_gem_object *gem_obj) @@ -4051,8 +4051,14 @@ init_ring_lists(struct intel_ring_buffer *ring) void i915_gem_load(struct drm_device *dev) { - int i; drm_i915_private_t *dev_priv = dev->dev_private; + int i; + + dev_priv->slab = + kmem_cache_create("i915_gem_object", + sizeof(struct drm_i915_gem_object), 0, + SLAB_HWCACHE_ALIGN, + NULL); INIT_LIST_HEAD(&dev_priv->mm.active_list); INIT_LIST_HEAD(&dev_priv->mm.flushing_list); -- 1.7.4.1