diff options
author | Christoph Hellwig <hch@lst.de> | 2007-02-12 00:51:58 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-12 09:48:28 -0800 |
commit | d003fb70fd356d0684ee0cd37a785e058c8678de (patch) | |
tree | 2367a8afa16defd85633665fbdb2a9192cbe6081 | |
parent | fb58b7316a99703afb8d076b0e5f3e1e387e4b30 (diff) |
[PATCH] remove sb->s_files and file_list_lock usage in dquot.c
Iterate over sb->s_inodes instead of sb->s_files in add_dquot_ref. This
reduces list search and lock hold time aswell as getting rid of one of the
few uses of file_list_lock which Ingo identified as a scalability problem.
Previously we called dq_op->initialize for every inode handing of a
writeable file that wasn't initialized before. Now we're calling it for
every inode that has a non-zero i_writecount, aka a writeable file
descriptor refering to it.
Thanks a lot to Jan Kara for running this patch through his quota test
harness.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | fs/dquot.c | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/fs/dquot.c b/fs/dquot.c index 5bdc4b2a872a..9eb166f91489 100644 --- a/fs/dquot.c +++ b/fs/dquot.c @@ -688,23 +688,27 @@ static int dqinit_needed(struct inode *inode, int type) /* This routine is guarded by dqonoff_mutex mutex */ static void add_dquot_ref(struct super_block *sb, int type) { - struct list_head *p; + struct inode *inode; restart: - file_list_lock(); - list_for_each(p, &sb->s_files) { - struct file *filp = list_entry(p, struct file, f_u.fu_list); - struct inode *inode = filp->f_path.dentry->d_inode; - if (filp->f_mode & FMODE_WRITE && dqinit_needed(inode, type)) { - struct dentry *dentry = dget(filp->f_path.dentry); - file_list_unlock(); - sb->dq_op->initialize(inode, type); - dput(dentry); - /* As we may have blocked we had better restart... */ - goto restart; - } + spin_lock(&inode_lock); + list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { + if (!atomic_read(&inode->i_writecount)) + continue; + if (!dqinit_needed(inode, type)) + continue; + if (inode->i_state & (I_FREEING|I_WILL_FREE)) + continue; + + __iget(inode); + spin_unlock(&inode_lock); + + sb->dq_op->initialize(inode, type); + iput(inode); + /* As we may have blocked we had better restart... */ + goto restart; } - file_list_unlock(); + spin_unlock(&inode_lock); } /* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */ |