[PATCH 1/2] Btrfs: return free space to global_rsv as much as possible

[PATCH 1/2] Btrfs: return free space to global_rsv as much as possible

[Liu Bo]

@full is not protected within global_rsv.lock, so we may think global_rsv
is already full but in fact it's not, so we miss the opportunity to return
free space to global_rsv directly when we release other block_rsvs.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
---
 fs/btrfs/extent-tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 9c01509..009980c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4637,7 +4637,7 @@ void btrfs_block_rsv_release(struct btrfs_root *root,
 			     u64 num_bytes)
 {
 	struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
-	if (global_rsv->full || global_rsv == block_rsv ||
+	if (global_rsv == block_rsv ||
 	    block_rsv->space_info != global_rsv->space_info)
 		global_rsv = NULL;
 	block_rsv_release_bytes(root->fs_info, block_rsv, global_rsv,
-- 
1.8.2.1

[PATCH 2/2] Btrfs: release subvolume's block_rsv before transaction commit

[Liu Bo]

We don't have to keep subvolume's block_rsv during transaction commit,
and within transaction commit, we may also need the free space reclaimed
from this block_rsv to process delayed refs.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
---
 fs/btrfs/ioctl.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 21da576..347bf61 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -417,7 +417,8 @@ static noinline int create_subvol(struct inode *dir,
 	trans = btrfs_start_transaction(root, 0);
 	if (IS_ERR(trans)) {
 		ret = PTR_ERR(trans);
-		goto out;
+		btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
+		return ret;
 	}
 	trans->block_rsv = &block_rsv;
 	trans->bytes_reserved = block_rsv.size;
@@ -542,6 +543,8 @@ static noinline int create_subvol(struct inode *dir,
 fail:
 	trans->block_rsv = NULL;
 	trans->bytes_reserved = 0;
+	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
+
 	if (async_transid) {
 		*async_transid = trans->transid;
 		err = btrfs_commit_transaction_async(trans, root, 1);
@@ -555,8 +558,6 @@ fail:
 
 	if (!ret)
 		d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
-out:
-	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 	return ret;
 }
 
-- 
1.8.2.1

Re: [PATCH 2/2] Btrfs: release subvolume's block_rsv before transaction commit

[Josef Bacik]

On 12/29/2013 08:44 AM, Liu Bo wrote:
> We don't have to keep subvolume's block_rsv during transaction commit,
> and within transaction commit, we may also need the free space reclaimed
> from this block_rsv to process delayed refs.
>
> Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
> ---
>   fs/btrfs/ioctl.c | 7 ++++---
>   1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 21da576..347bf61 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -417,7 +417,8 @@ static noinline int create_subvol(struct inode *dir,
>   	trans = btrfs_start_transaction(root, 0);
>   	if (IS_ERR(trans)) {
>   		ret = PTR_ERR(trans);
> -		goto out;
> +		btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
> +		return ret;
>   	}
>   	trans->block_rsv = &block_rsv;
>   	trans->bytes_reserved = block_rsv.size;
> @@ -542,6 +543,8 @@ static noinline int create_subvol(struct inode *dir,
>   fail:
>   	trans->block_rsv = NULL;
>   	trans->bytes_reserved = 0;
> +	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
> +
>   	if (async_transid) {
>   		*async_transid = trans->transid;
>   		err = btrfs_commit_transaction_async(trans, root, 1);
> @@ -555,8 +558,6 @@ fail:
>   
>   	if (!ret)
>   		d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
> -out:
> -	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
>   	return ret;
>   }
>   

Doesn't compile, please rebase onto new btrfs-next and resubmit. Thanks,

Josef

[PATCH v2] Btrfs: release subvolume's block_rsv before transaction commit

[Liu Bo]

We don't have to keep subvolume's block_rsv during transaction commit,
and within transaction commit, we may also need the free space reclaimed
from this block_rsv to process delayed refs.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
---
v2: rebase onto the latest btrfs-next.

 fs/btrfs/ioctl.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 3970f32..332b624 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -436,7 +436,9 @@ static noinline int create_subvol(struct inode *dir,
 	trans = btrfs_start_transaction(root, 0);
 	if (IS_ERR(trans)) {
 		ret = PTR_ERR(trans);
-		goto out;
+		btrfs_subvolume_release_metadata(root, &block_rsv,
+						 qgroup_reserved);
+		return ret;
 	}
 	trans->block_rsv = &block_rsv;
 	trans->bytes_reserved = block_rsv.size;
@@ -561,6 +563,8 @@ static noinline int create_subvol(struct inode *dir,
 fail:
 	trans->block_rsv = NULL;
 	trans->bytes_reserved = 0;
+	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
+
 	if (async_transid) {
 		*async_transid = trans->transid;
 		err = btrfs_commit_transaction_async(trans, root, 1);
@@ -574,14 +578,10 @@ fail:
 
 	if (!ret) {
 		inode = btrfs_lookup_dentry(dir, dentry);
-		if (IS_ERR(inode)) {
-			ret = PTR_ERR(inode);
-			goto out;
-		}
+		if (IS_ERR(inode))
+			return PTR_ERR(inode);
 		d_instantiate(dentry, inode);
 	}
-out:
-	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 	return ret;
 }
 
-- 
1.8.1.4