Attachment 55880 Details for Bug 44999 – use private slab for i915 gem objects

[patch] use private slab for i915 gem objects

slab.patch (text/plain), 3.02 KB, created by Daniel Vetter on 2012-01-20 16:05:14 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Daniel Vetter

Created: 2012-01-20 16:05:14 UTC

Size: 3.02 KB

patch

obsolete

>commit af1a10a260fd26d8d0e0c53288781c0a777e5c8c
>Author: Chris Wilson <chris@chris-wilson.co.uk>
>Date:   Sat Apr 16 10:17:44 2011 +0100
>
>    drm/i915: Use a slab for object allocation
>    
>    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 <chris@chris-wilson.co.uk>
>
>diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
>index 8122738..c0b692f 100644
>--- a/drivers/gpu/drm/i915/i915_dma.c
>+++ b/drivers/gpu/drm/i915/i915_dma.c
>@@ -2202,6 +2202,9 @@ 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 f02a5f5..b65e984 100644
>--- a/drivers/gpu/drm/i915/i915_drv.h
>+++ b/drivers/gpu/drm/i915/i915_drv.h
>@@ -285,6 +285,8 @@ 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 9d518b5..02cebaf 100644
>--- a/drivers/gpu/drm/i915/i915_gem.c
>+++ b/drivers/gpu/drm/i915/i915_gem.c
>@@ -211,7 +211,7 @@ i915_gem_create(struct drm_file *file,
> 	if (ret) {
> 		drm_gem_object_release(&obj->base);
> 		i915_gem_info_remove_obj(dev->dev_private, obj->base.size);
>-		kfree(obj);
>+		kmem_cache_free(dev_priv->slab, obj);
> 		return ret;
> 	}
> 
>@@ -3606,12 +3606,12 @@ struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
> 	struct drm_i915_gem_object *obj;
> 	struct address_space *mapping;
> 
>-	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
>+	obj = kmem_cache_alloc(dev_priv->slab, GFP_KERNEL | __GFP_ZERO);
> 	if (obj == NULL)
> 		return NULL;
> 
> 	if (drm_gem_object_init(dev, &obj->base, size) != 0) {
>-		kfree(obj);
>+		kmem_cache_free(dev_priv->slab, obj);
> 		return NULL;
> 	}
> 
>@@ -3684,7 +3684,7 @@ 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)
>@@ -3878,6 +3878,13 @@ i915_gem_load(struct drm_device *dev)
> 	int i;
> 	drm_i915_private_t *dev_priv = dev->dev_private;
> 
>+	dev_priv->slab = kmem_cache_create("i915_gem_object",
>+					   sizeof(struct drm_i915_gem_object),
>+					   0,
>+					   SLAB_HWCACHE_ALIGN,
>+					   NULL);
>+	WARN_ON(!dev_priv->slab);
>+
> 	INIT_LIST_HEAD(&dev_priv->mm.active_list);
> 	INIT_LIST_HEAD(&dev_priv->mm.flushing_list);
> 	INIT_LIST_HEAD(&dev_priv->mm.inactive_list);

Actions: View | Splinter Review

Attachments on bug 44999: 55842 | 55843 | 55844 | 55845 | 55880

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.