[PATCH 3/3] drm/ttm: enable swapout for reserved BOs during allocation

[Christian König]

Am 25.12.2017 um 07:07 schrieb Roger He:
> if the bo shares same reservation object then not lock it again
> at swapout time to make it possible to swap out.
>
> v2: refine the commmit message
>
> Change-Id: I1e87954564f38ad298bf6e4ff88c9f26f291a62d
> Signed-off-by: Roger He <Hongbo.He at amd.com>

Reviewed-by: Christian König <christian.koenig at amd.com>

> ---
>   drivers/gpu/drm/ttm/ttm_bo.c     | 15 +++++++++++----
>   drivers/gpu/drm/ttm/ttm_memory.c | 12 ++++++++----
>   include/drm/ttm/ttm_bo_api.h     |  3 ++-
>   3 files changed, 21 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index 5e64091..ec42bb3 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -1697,18 +1697,20 @@ EXPORT_SYMBOL(ttm_bo_synccpu_write_release);
>    * A buffer object shrink method that tries to swap out the first
>    * buffer object on the bo_global::swap_lru list.
>    */
> -int ttm_bo_swapout(struct ttm_bo_global *glob)
> +int ttm_bo_swapout(struct ttm_bo_global *glob, struct ttm_operation_ctx *ctx)
>   {
>   	struct ttm_buffer_object *bo;
>   	int ret = -EBUSY;
> +	bool locked;
>   	unsigned i;
>   
>   	spin_lock(&glob->lru_lock);
>   	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
>   		list_for_each_entry(bo, &glob->swap_lru[i], swap) {
> -			ret = reservation_object_trylock(bo->resv) ? 0 : -EBUSY;
> -			if (!ret)
> +			if (ttm_bo_evict_swapout_allowable(bo, ctx, &locked)) {
> +				ret = 0;
>   				break;
> +			}
>   		}
>   		if (!ret)
>   			break;
> @@ -1784,7 +1786,12 @@ EXPORT_SYMBOL(ttm_bo_swapout);
>   
>   void ttm_bo_swapout_all(struct ttm_bo_device *bdev)
>   {
> -	while (ttm_bo_swapout(bdev->glob) == 0)
> +	struct ttm_operation_ctx ctx = {
> +		.interruptible = false,
> +		.no_wait_gpu = false
> +	};
> +
> +	while (ttm_bo_swapout(bdev->glob, &ctx) == 0)
>   		;
>   }
>   EXPORT_SYMBOL(ttm_bo_swapout_all);
> diff --git a/drivers/gpu/drm/ttm/ttm_memory.c b/drivers/gpu/drm/ttm/ttm_memory.c
> index 102b326..aa0c381 100644
> --- a/drivers/gpu/drm/ttm/ttm_memory.c
> +++ b/drivers/gpu/drm/ttm/ttm_memory.c
> @@ -211,7 +211,7 @@ static bool ttm_zones_above_swap_target(struct ttm_mem_global *glob,
>    */
>   
>   static void ttm_shrink(struct ttm_mem_global *glob, bool from_wq,
> -		       uint64_t extra)
> +			uint64_t extra, struct ttm_operation_ctx *ctx)
>   {
>   	int ret;
>   
> @@ -219,7 +219,7 @@ static void ttm_shrink(struct ttm_mem_global *glob, bool from_wq,
>   
>   	while (ttm_zones_above_swap_target(glob, from_wq, extra)) {
>   		spin_unlock(&glob->lock);
> -		ret = ttm_bo_swapout(glob->bo_glob);
> +		ret = ttm_bo_swapout(glob->bo_glob, ctx);
>   		spin_lock(&glob->lock);
>   		if (unlikely(ret != 0))
>   			break;
> @@ -230,10 +230,14 @@ static void ttm_shrink(struct ttm_mem_global *glob, bool from_wq,
>   
>   static void ttm_shrink_work(struct work_struct *work)
>   {
> +	struct ttm_operation_ctx ctx = {
> +		.interruptible = false,
> +		.no_wait_gpu = false
> +	};
>   	struct ttm_mem_global *glob =
>   	    container_of(work, struct ttm_mem_global, work);
>   
> -	ttm_shrink(glob, true, 0ULL);
> +	ttm_shrink(glob, true, 0ULL, &ctx);
>   }
>   
>   static int ttm_mem_init_kernel_zone(struct ttm_mem_global *glob,
> @@ -520,7 +524,7 @@ static int ttm_mem_global_alloc_zone(struct ttm_mem_global *glob,
>   			return -ENOMEM;
>   		if (unlikely(count-- == 0))
>   			return -ENOMEM;
> -		ttm_shrink(glob, false, memory + (memory >> 2) + 16);
> +		ttm_shrink(glob, false, memory + (memory >> 2) + 16, ctx);
>   	}
>   
>   	return 0;
> diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h
> index 24a8db7..f1c74c2 100644
> --- a/include/drm/ttm/ttm_bo_api.h
> +++ b/include/drm/ttm/ttm_bo_api.h
> @@ -752,7 +752,8 @@ ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
>   		  const char __user *wbuf, char __user *rbuf,
>   		  size_t count, loff_t *f_pos, bool write);
>   
> -int ttm_bo_swapout(struct ttm_bo_global *glob);
> +int ttm_bo_swapout(struct ttm_bo_global *glob,
> +			struct ttm_operation_ctx *ctx);
>   void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
>   int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo);
>   #endif