diff options
| author | Jan Kara <jack@suse.cz> | 2017-08-07 13:19:50 +0200 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2017-08-17 22:07:59 +0200 |
| commit | 7b9ca4c61bc278b771fb57d6290a31ab1fc7fdac (patch) | |
| tree | 3e9c7464525efa2a9dd50d02e7fe8f7df45a4961 /fs/ext4/super.c | |
| parent | f4a8116a4c8c8f754d0ec1498a2ba4b63d114e6a (diff) | |
quota: Reduce contention on dq_data_lock
dq_data_lock is currently used to protect all modifications of quota
accounting information, consistency of quota accounting on the inode,
and dquot pointers from inode. As a result contention on the lock can be
pretty heavy.
Reduce the contention on the lock by protecting quota accounting
information by a new dquot->dq_dqb_lock and consistency of quota
accounting with inode usage by inode->i_lock.
This change reduces time to create 500000 files on ext4 on ramdisk by 50
different processes in separate directories by 6% when user quota is
turned on. When those 50 processes belong to 50 different users, the
improvement is about 9%.
Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'fs/ext4/super.c')
| -rw-r--r-- | fs/ext4/super.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 16a877a0f309..67ce21224dab 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5194,7 +5194,7 @@ static int ext4_statfs_project(struct super_block *sb, dquot = dqget(sb, qid); if (IS_ERR(dquot)) return PTR_ERR(dquot); - spin_lock(&dq_data_lock); + spin_lock(&dquot->dq_dqb_lock); limit = (dquot->dq_dqb.dqb_bsoftlimit ? dquot->dq_dqb.dqb_bsoftlimit : @@ -5217,7 +5217,7 @@ static int ext4_statfs_project(struct super_block *sb, (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0; } - spin_unlock(&dq_data_lock); + spin_unlock(&dquot->dq_dqb_lock); dqput(dquot); return 0; } |