Re: [PATCH 04/11] btrfs: unify compression ops with workspace_manager

[Nikolay Borisov]

On 28.01.19 Ð. 23:24 Ñ., Dennis Zhou wrote:
> Make the workspace_manager own the interface operations rather than
> managing index-paired arrays for the workspace_manager and compression
> operations.
> 
> Signed-off-by: Dennis Zhou <dennis@xxxxxxxxxx>

Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>

> ---
>  fs/btrfs/compression.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
> index bda7e8d2cbc7..b7e986e16640 100644
> --- a/fs/btrfs/compression.c
> +++ b/fs/btrfs/compression.c
> @@ -777,6 +777,7 @@ const struct btrfs_compress_op btrfs_heuristic_compress = {
>  };
>  
>  struct workspace_manager {
> +	const struct btrfs_compress_op *ops;
>  	struct list_head idle_ws;
>  	spinlock_t ws_lock;
>  	/* Number of free workspaces */
> @@ -802,6 +803,8 @@ void __init btrfs_init_compress(void)
>  	int i;
>  
>  	for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) {
> +		wsm[i].ops = btrfs_compress_op[i];
> +
>  		INIT_LIST_HEAD(&wsm[i].idle_ws);
>  		spin_lock_init(&wsm[i].ws_lock);
>  		atomic_set(&wsm[i].total_ws, 0);
> @@ -811,7 +814,7 @@ void __init btrfs_init_compress(void)
>  		 * Preallocate one workspace for each compression type so
>  		 * we can guarantee forward progress in the worst case
>  		 */
> -		workspace = btrfs_compress_op[i]->alloc_workspace();
> +		workspace = wsm[i].ops->alloc_workspace();
>  		if (IS_ERR(workspace)) {
>  			pr_warn("BTRFS: cannot preallocate compression workspace, will try later\n");
>  		} else {
> @@ -874,7 +877,7 @@ static struct list_head *find_workspace(int type)
>  	 * context of btrfs_compress_bio/btrfs_compress_pages
>  	 */
>  	nofs_flag = memalloc_nofs_save();
> -	workspace = btrfs_compress_op[type]->alloc_workspace();
> +	workspace = wsm[type].ops->alloc_workspace();
>  	memalloc_nofs_restore(nofs_flag);
>  
>  	if (IS_ERR(workspace)) {
> @@ -932,7 +935,7 @@ static void free_workspace(int type, struct list_head *workspace)
>  	}
>  	spin_unlock(ws_lock);
>  
> -	btrfs_compress_op[type]->free_workspace(workspace);
> +	wsm[type].ops->free_workspace(workspace);
>  	atomic_dec(total_ws);
>  wake:
>  	cond_wake_up(ws_wait);
> @@ -950,7 +953,7 @@ static void free_workspaces(void)
>  		while (!list_empty(&wsm[i].idle_ws)) {
>  			workspace = wsm[i].idle_ws.next;
>  			list_del(workspace);
> -			btrfs_compress_op[i]->free_workspace(workspace);
> +			wsm[i].ops->free_workspace(workspace);
>  			atomic_dec(&wsm[i].total_ws);
>  		}
>  	}
>