diff mbox series

[v3,7/8] drm/v3d: Use gemfs/THP in BO creation if available

Message ID 20240421215309.660018-8-mcanal@igalia.com (mailing list archive)
State New, archived
Headers show
Series drm/v3d: Enable Big and Super Pages | expand

Commit Message

Maíra Canal April 21, 2024, 9:44 p.m. UTC
Although Big/Super Pages could appear naturally, it would be quite hard
to have 1MB or 64KB allocated contiguously naturally. Therefore, we can
force the creation of large pages allocated contiguously by using a
mountpoint with "huge=within_size" enabled.

As V3D has a mountpoint with "huge=within_size" (if user has THP enabled),
use this mountpoint for BO creation if available. This will allow us to create
large pages allocated contiguously and make use of Big/Super Pages.

Signed-off-by: Maíra Canal <mcanal@igalia.com>
---
 drivers/gpu/drm/v3d/v3d_bo.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

Comments

Tvrtko Ursulin April 22, 2024, 9:59 a.m. UTC | #1
On 21/04/2024 22:44, Maíra Canal wrote:
> Although Big/Super Pages could appear naturally, it would be quite hard
> to have 1MB or 64KB allocated contiguously naturally. Therefore, we can
> force the creation of large pages allocated contiguously by using a
> mountpoint with "huge=within_size" enabled.
> 
> As V3D has a mountpoint with "huge=within_size" (if user has THP enabled),
> use this mountpoint for BO creation if available. This will allow us to create
> large pages allocated contiguously and make use of Big/Super Pages.
> 
> Signed-off-by: Maíra Canal <mcanal@igalia.com>
> ---
>   drivers/gpu/drm/v3d/v3d_bo.c | 21 +++++++++++++++++++--
>   1 file changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c
> index 79e31c5299b1..16ac26c31c6b 100644
> --- a/drivers/gpu/drm/v3d/v3d_bo.c
> +++ b/drivers/gpu/drm/v3d/v3d_bo.c
> @@ -94,6 +94,7 @@ v3d_bo_create_finish(struct drm_gem_object *obj)
>   	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
>   	struct v3d_bo *bo = to_v3d_bo(obj);
>   	struct sg_table *sgt;
> +	u64 align;
>   	int ret;
>   
>   	/* So far we pin the BO in the MMU for its lifetime, so use
> @@ -103,6 +104,15 @@ v3d_bo_create_finish(struct drm_gem_object *obj)
>   	if (IS_ERR(sgt))
>   		return PTR_ERR(sgt);
>   
> +	if (!v3d->gemfs)
> +		align = SZ_4K;
> +	else if (obj->size >= SZ_1M)
> +		align = SZ_1M;
> +	else if (obj->size >= SZ_64K)
> +		align = SZ_64K;
> +	else
> +		align = SZ_4K;

V3d has one GPU address space, right? I wonder if one day fragmentation 
could become an issue but it's a problem for another day. Patch looks 
fine to me.

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>

Regards,

Tvrtko

> +
>   	spin_lock(&v3d->mm_lock);
>   	/* Allocate the object's space in the GPU's page tables.
>   	 * Inserting PTEs will happen later, but the offset is for the
> @@ -110,7 +120,7 @@ v3d_bo_create_finish(struct drm_gem_object *obj)
>   	 */
>   	ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
>   					 obj->size >> V3D_MMU_PAGE_SHIFT,
> -					 SZ_4K >> V3D_MMU_PAGE_SHIFT, 0, 0);
> +					 align >> V3D_MMU_PAGE_SHIFT, 0, 0);
>   	spin_unlock(&v3d->mm_lock);
>   	if (ret)
>   		return ret;
> @@ -130,10 +140,17 @@ struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
>   			     size_t unaligned_size)
>   {
>   	struct drm_gem_shmem_object *shmem_obj;
> +	struct v3d_dev *v3d = to_v3d_dev(dev);
>   	struct v3d_bo *bo;
>   	int ret;
>   
> -	shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
> +	/* Let the user opt out of allocating the BOs with THP */
> +	if (v3d->gemfs)
> +		shmem_obj = drm_gem_shmem_create_with_mnt(dev, unaligned_size,
> +							  v3d->gemfs);
> +	else
> +		shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
> +
>   	if (IS_ERR(shmem_obj))
>   		return ERR_CAST(shmem_obj);
>   	bo = to_v3d_bo(&shmem_obj->base);
diff mbox series

Patch

diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c
index 79e31c5299b1..16ac26c31c6b 100644
--- a/drivers/gpu/drm/v3d/v3d_bo.c
+++ b/drivers/gpu/drm/v3d/v3d_bo.c
@@ -94,6 +94,7 @@  v3d_bo_create_finish(struct drm_gem_object *obj)
 	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
 	struct v3d_bo *bo = to_v3d_bo(obj);
 	struct sg_table *sgt;
+	u64 align;
 	int ret;
 
 	/* So far we pin the BO in the MMU for its lifetime, so use
@@ -103,6 +104,15 @@  v3d_bo_create_finish(struct drm_gem_object *obj)
 	if (IS_ERR(sgt))
 		return PTR_ERR(sgt);
 
+	if (!v3d->gemfs)
+		align = SZ_4K;
+	else if (obj->size >= SZ_1M)
+		align = SZ_1M;
+	else if (obj->size >= SZ_64K)
+		align = SZ_64K;
+	else
+		align = SZ_4K;
+
 	spin_lock(&v3d->mm_lock);
 	/* Allocate the object's space in the GPU's page tables.
 	 * Inserting PTEs will happen later, but the offset is for the
@@ -110,7 +120,7 @@  v3d_bo_create_finish(struct drm_gem_object *obj)
 	 */
 	ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
 					 obj->size >> V3D_MMU_PAGE_SHIFT,
-					 SZ_4K >> V3D_MMU_PAGE_SHIFT, 0, 0);
+					 align >> V3D_MMU_PAGE_SHIFT, 0, 0);
 	spin_unlock(&v3d->mm_lock);
 	if (ret)
 		return ret;
@@ -130,10 +140,17 @@  struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
 			     size_t unaligned_size)
 {
 	struct drm_gem_shmem_object *shmem_obj;
+	struct v3d_dev *v3d = to_v3d_dev(dev);
 	struct v3d_bo *bo;
 	int ret;
 
-	shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
+	/* Let the user opt out of allocating the BOs with THP */
+	if (v3d->gemfs)
+		shmem_obj = drm_gem_shmem_create_with_mnt(dev, unaligned_size,
+							  v3d->gemfs);
+	else
+		shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
+
 	if (IS_ERR(shmem_obj))
 		return ERR_CAST(shmem_obj);
 	bo = to_v3d_bo(&shmem_obj->base);