xfs: remove i_iolock and use i_rwsem in the VFS inode instead

This patch drops the XFS-own i_iolock and uses the VFS i_rwsem which
recently replaced i_mutex instead.  This means we only have to take
one lock instead of two in many fast path operations, and we can
also shrink the xfs_inode structure.  Thanks to the xfs_ilock family
there is very little churn, the only thing of note is that we need
to switch to use the lock_two_directory helper for taking the i_rwsem
on two inodes in a few places to make sure our lock order matches
the one used in the VFS.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Christoph Hellwig
2016-11-30 14:33:25 +11:00
committed by Dave Chinner
parent f8319483f5
commit 6552321831
14 changed files with 86 additions and 159 deletions

View File

@@ -983,15 +983,13 @@ xfs_vn_setattr(
struct xfs_inode *ip = XFS_I(d_inode(dentry));
uint iolock = XFS_IOLOCK_EXCL;
xfs_ilock(ip, iolock);
error = xfs_break_layouts(d_inode(dentry), &iolock, true);
if (!error) {
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
iolock |= XFS_MMAPLOCK_EXCL;
error = xfs_break_layouts(d_inode(dentry), &iolock);
if (error)
return error;
error = xfs_vn_setattr_size(dentry, iattr);
}
xfs_iunlock(ip, iolock);
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
error = xfs_setattr_size(ip, iattr);
xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
} else {
error = xfs_vn_setattr_nonsize(dentry, iattr);
}