Re: [PATCH v3 3/4] drm/i915: pre-alloc instead of drm_mm search/get_block

On Sat, Jul 27, 2013 at 04:21:27PM +0200, David Herrmann wrote:

i915 is the last user of the weird search+get_block drm_mm API. Convert it to an explicit kmalloc()+insert_node(). This drops the last user of the node-cache in drm_mm. We can remove it now in a follow-up patch.

v2:

• simplify error path in i915_setup_compression()

v3:

• simplify error path even more

Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Chris Wilson chris@chris-wilson.co.uk Signed-off-by: David Herrmann dh.herrmann@gmail.com

I think this won't conflict badly with the ongoing VMA rework in drm/i915, so

Acked-by: Daniel Vetter daniel.vetter@ffwll.ch

for merging through drm-next directly. -Daniel

---

drivers/gpu/drm/i915/i915_gem_stolen.c | 78 ++++++++++++++++++++-------------- 1 file changed, 47 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index e355170..a3d1a12 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -112,34 +112,36 @@ static int i915_setup_compression(struct drm_device *dev, int size) { struct drm_i915_private *dev_priv = dev->dev_private; struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);

• int ret;

• /* Try to over-allocate to reduce reallocations and fragmentation */
• compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen,

• 			   size <<= 1, 4096,
  

• 			   DRM_MM_SEARCH_DEFAULT);
  

• if (!compressed_fb)

• compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen,
  

• 				   size >>= 1, 4096,
  

• 				   DRM_MM_SEARCH_DEFAULT);
  

• if (compressed_fb)

• compressed_fb = drm_mm_get_block(compressed_fb, size, 4096);
  

• compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL); if (!compressed_fb)

• goto err;
  

• goto err_llb;
  

• /* Try to over-allocate to reduce reallocations and fragmentation */

• ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,

• 		 size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
  

• if (ret)

• ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
  

• 			 size >>= 1, 4096,
  

• 			 DRM_MM_SEARCH_DEFAULT);
  

• if (ret)

• goto err_llb;
  
  

  if (HAS_PCH_SPLIT(dev)) I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start); else if (IS_GM45(dev)) { I915_WRITE(DPFC_CB_BASE, compressed_fb->start); } else {

• compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
  

• 				    4096, 4096,
  

• 				    DRM_MM_SEARCH_DEFAULT);
  

• if (compressed_llb)
  

• 	compressed_llb = drm_mm_get_block(compressed_llb,
  

• 					  4096, 4096);
  

• compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
  

  if (!compressed_llb) goto err_fb;

• ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
  

• 			 4096, 4096, DRM_MM_SEARCH_DEFAULT);
  

• if (ret)
  

• 	goto err_fb;
  

• dev_priv->fbc.compressed_llb = compressed_llb;

  I915_WRITE(FBC_CFB_BASE,

@@ -157,8 +159,10 @@ static int i915_setup_compression(struct drm_device *dev, int size) return 0;

err_fb:

• drm_mm_put_block(compressed_fb);

-err:

• kfree(compressed_llb);
• drm_mm_remove_node(compressed_fb);

+err_llb:

• kfree(compressed_fb); pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size); return -ENOSPC;

} @@ -186,11 +190,15 @@ void i915_gem_stolen_cleanup_compression(struct drm_device *dev) if (dev_priv->fbc.size == 0) return;

• if (dev_priv->fbc.compressed_fb)

• drm_mm_put_block(dev_priv->fbc.compressed_fb);
  

• if (dev_priv->fbc.compressed_fb) {

• drm_mm_remove_node(dev_priv->fbc.compressed_fb);
  

• kfree(dev_priv->fbc.compressed_fb);
  

• }

• if (dev_priv->fbc.compressed_llb)

• drm_mm_put_block(dev_priv->fbc.compressed_llb);
  

• if (dev_priv->fbc.compressed_llb) {

• drm_mm_remove_node(dev_priv->fbc.compressed_llb);
  

• kfree(dev_priv->fbc.compressed_llb);
  

• }

  dev_priv->fbc.size = 0;

} @@ -323,6 +331,7 @@ i915_gem_object_create_stolen(struct drm_device *dev, u32 size) struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; struct drm_mm_node *stolen;

• int ret;

  if (!drm_mm_initialized(&dev_priv->mm.stolen)) return NULL;

@@ -331,18 +340,23 @@ i915_gem_object_create_stolen(struct drm_device *dev, u32 size) if (size == 0) return NULL;

• stolen = drm_mm_search_free(&dev_priv->mm.stolen, size, 4096,

• 		    DRM_MM_SEARCH_DEFAULT);
  

• if (stolen)

• stolen = drm_mm_get_block(stolen, size, 4096);
  

• if (stolen == NULL)

• stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);

• if (!stolen) return NULL;

• ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,

• 		 4096, DRM_MM_SEARCH_DEFAULT);
  

• if (ret) {

• kfree(stolen);
  

• return NULL;
  

• }

• obj = _i915_gem_object_create_stolen(dev, stolen); if (obj) return obj;

• drm_mm_put_block(stolen);

• drm_mm_remove_node(stolen);
• kfree(stolen); return NULL;

}

@@ -386,7 +400,8 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev, obj = _i915_gem_object_create_stolen(dev, stolen); if (obj == NULL) { DRM_DEBUG_KMS("failed to allocate stolen object\n");

• drm_mm_put_block(stolen);
  

• drm_mm_remove_node(stolen);
  

• kfree(stolen);
  

  return NULL; }

@@ -426,7 +441,8 @@ void i915_gem_object_release_stolen(struct drm_i915_gem_object *obj) { if (obj->stolen) {

• drm_mm_put_block(obj->stolen);
  

• drm_mm_remove_node(obj->stolen);
  

• kfree(obj->stolen);
  

  obj->stolen = NULL; }

}

1.8.3.4