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>
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 3011b87..0a80543 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -700,7 +700,7 @@
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 @@
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 @@
/*
* 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 @@
* 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