diff options
author | Christoph Hellwig <hch@infradead.org> | 2011-12-18 20:00:09 +0000 |
---|---|---|
committer | Ben Myers <bpm@sgi.com> | 2012-01-17 15:06:45 -0600 |
commit | 474fce067521a40dbacc722e8ba119e81c2d31bf (patch) | |
tree | fd923aa42a5304182e8a8c64ca5d130f9afef286 /fs/xfs/xfs_inode.c | |
parent | 49e4c70e52a2bc2090e5a4e003e2888af21d6a2b (diff) | |
download | lwn-474fce067521a40dbacc722e8ba119e81c2d31bf.tar.gz lwn-474fce067521a40dbacc722e8ba119e81c2d31bf.zip |
xfs: replace i_flock with a sleeping bitlock
We almost never block on i_flock, the exception is synchronous inode
flushing. Instead of bloating the inode with a 16/24-byte completion
that we abuse as a semaphore just implement it as a bitlock that uses
a bit waitqueue for the rare sleeping path. This primarily is a
tradeoff between a much smaller inode and a faster non-blocking
path vs faster wakeups, and we are much better off with the former.
A small downside is that we will lose lockdep checking for i_flock, but
given that it's always taken inside the ilock that should be acceptable.
Note that for example the inode writeback locking is implemented in a
very similar way.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Diffstat (limited to 'fs/xfs/xfs_inode.c')
-rw-r--r-- | fs/xfs/xfs_inode.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 96b29e3286db..eeb60d31b086 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -2396,7 +2396,7 @@ xfs_iflush( XFS_STATS_INC(xs_iflush_count); ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); - ASSERT(!completion_done(&ip->i_flush)); + ASSERT(xfs_isiflocked(ip)); ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE || ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)); @@ -2512,7 +2512,7 @@ xfs_iflush_int( #endif ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); - ASSERT(!completion_done(&ip->i_flush)); + ASSERT(xfs_isiflocked(ip)); ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE || ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)); |