[PATCH] ext4: random performance optimizations for ext4_setattr

[PATCH] ext4: random performance optimizations for ext4_setattr

[Dmitry Monakhov]

If quota is not enabled it is not necessery to start separate
transaction for uid, gid and quota credits changes.

If inode wasn't added to orphan list when it is not necessary
to remove it from the list. This allow to avoid locking on
per-sb s_orphan_lock mutex.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
---
 fs/ext4/inode.c |   15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3996151..b498274 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5418,6 +5418,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = dentry->d_inode;
 	int error, rc = 0;
+	int orphan = 0;
 	const unsigned int ia_valid = attr->ia_valid;
 
 	error = inode_change_ok(inode, attr);
@@ -5426,8 +5427,13 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 
 	if (ia_valid & ATTR_SIZE)
 		dquot_initialize(inode);
-	if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
-		(ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
+	/*
+	 * If quota is active when uig, git and quota's credits must
+	 * being changed in the one transaction.
+	*/
+	if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode) && (
+		(ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
+		(ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid))) {
 		handle_t *handle;
 
 		/* (user+group)*(old+new) structure, inode write (sb,
@@ -5477,6 +5483,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 		}
 
 		error = ext4_orphan_add(handle, inode);
+		orphan = 1;
 		EXT4_I(inode)->i_disksize = attr->ia_size;
 		rc = ext4_mark_inode_dirty(handle, inode);
 		if (!error)
@@ -5491,9 +5498,11 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 				handle = ext4_journal_start(inode, 3);
 				if (IS_ERR(handle)) {
 					ext4_orphan_del(NULL, inode);
+					orphan = 0;
 					goto err_out;
 				}
 				ext4_orphan_del(handle, inode);
+				orphan = 0;
 				ext4_journal_stop(handle);
 				goto err_out;
 			}
@@ -5508,7 +5517,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 	/* If inode_setattr's call to ext4_truncate failed to get a
 	 * transaction handle at all, we need to clean up the in-core
 	 * orphan list manually. */
-	if (inode->i_nlink)
+	if (orphan && inode->i_nlink)
 		ext4_orphan_del(NULL, inode);
 
 	if (!rc && (ia_valid & ATTR_MODE))
-- 
1.6.3.3

Re: [PATCH] ext4: random performance optimizations for ext4_setattr

[Eric Sandeen]

Dmitry Monakhov wrote:
> If quota is not enabled it is not necessery to start separate
> transaction for uid, gid and quota credits changes.
> 
> If inode wasn't added to orphan list when it is not necessary
> to remove it from the list. This allow to avoid locking on
> per-sb s_orphan_lock mutex.
> 
> Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
> ---
>  fs/ext4/inode.c |   15 ++++++++++++---
>  1 files changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 3996151..b498274 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -5418,6 +5418,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
>  {
>  	struct inode *inode = dentry->d_inode;
>  	int error, rc = 0;
> +	int orphan = 0;
>  	const unsigned int ia_valid = attr->ia_valid;
>  
>  	error = inode_change_ok(inode, attr);
> @@ -5426,8 +5427,13 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
>  
>  	if (ia_valid & ATTR_SIZE)
>  		dquot_initialize(inode);
> -	if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
> -		(ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
> +	/*
> +	 * If quota is active when uig, git and quota's credits must

lame spell-check review ;)

"uid, gid, and ..."

-Eric

> +	 * being changed in the one transaction.
> +	*/
> +	if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode) && (
> +		(ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
> +		(ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid))) {
>  		handle_t *handle;
>  
>  		/* (user+group)*(old+new) structure, inode write (sb,
> @@ -5477,6 +5483,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
>  		}
>  
>  		error = ext4_orphan_add(handle, inode);
> +		orphan = 1;
>  		EXT4_I(inode)->i_disksize = attr->ia_size;
>  		rc = ext4_mark_inode_dirty(handle, inode);
>  		if (!error)
> @@ -5491,9 +5498,11 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
>  				handle = ext4_journal_start(inode, 3);
>  				if (IS_ERR(handle)) {
>  					ext4_orphan_del(NULL, inode);
> +					orphan = 0;
>  					goto err_out;
>  				}
>  				ext4_orphan_del(handle, inode);
> +				orphan = 0;
>  				ext4_journal_stop(handle);
>  				goto err_out;
>  			}
> @@ -5508,7 +5517,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
>  	/* If inode_setattr's call to ext4_truncate failed to get a
>  	 * transaction handle at all, we need to clean up the in-core
>  	 * orphan list manually. */
> -	if (inode->i_nlink)
> +	if (orphan && inode->i_nlink)
>  		ext4_orphan_del(NULL, inode);
>  
>  	if (!rc && (ia_valid & ATTR_MODE))