xfs: reduce ilock hold times in xfs_setattr_size

We do not need the ilock for most checks done in the beginning of
xfs_setattr_size.  Replace the long critical section before starting the
transaction with a smaller one around xfs_zero_eof and an optional one
inside xfs_qm_dqattach that isn't entered unless using quotas.  While
this isn't a big optimization for xfs_setattr_size itself it will allow
pushing the ilock into xfs_zero_eof itself later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Christoph Hellwig 2012-03-27 10:34:48 -04:00 committed by Ben Myers
parent 467f78992a
commit f38996f576

View File

@ -700,7 +700,7 @@ xfs_setattr_size(
xfs_off_t oldsize, newsize;
struct xfs_trans *tp;
int error;
uint lock_flags;
uint lock_flags = 0;
uint commit_flags = 0;
trace_xfs_setattr(ip);
@ -720,10 +720,10 @@ xfs_setattr_size(
ATTR_MTIME_SET|ATTR_KILL_SUID|ATTR_KILL_SGID|
ATTR_KILL_PRIV|ATTR_TIMES_SET)) == 0);
lock_flags = XFS_ILOCK_EXCL;
if (!(flags & XFS_ATTR_NOLOCK))
if (!(flags & XFS_ATTR_NOLOCK)) {
lock_flags |= XFS_IOLOCK_EXCL;
xfs_ilock(ip, lock_flags);
xfs_ilock(ip, lock_flags);
}
oldsize = inode->i_size;
newsize = iattr->ia_size;
@ -746,7 +746,7 @@ xfs_setattr_size(
/*
* Make sure that the dquots are attached to the inode.
*/
error = xfs_qm_dqattach_locked(ip, 0);
error = xfs_qm_dqattach(ip, 0);
if (error)
goto out_unlock;
@ -764,12 +764,12 @@ xfs_setattr_size(
* before the inode is joined to the transaction to modify
* i_size.
*/
xfs_ilock(ip, XFS_ILOCK_EXCL);
error = xfs_zero_eof(ip, newsize, oldsize);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
if (error)
goto out_unlock;
}
xfs_iunlock(ip, XFS_ILOCK_EXCL);
lock_flags &= ~XFS_ILOCK_EXCL;
/*
* We are going to log the inode size change in this transaction so