diff options
| author | Christoph Hellwig <hch@infradead.org> | 2012-04-23 15:58:33 +1000 |
|---|---|---|
| committer | Ben Myers <bpm@sgi.com> | 2012-05-14 16:20:26 -0500 |
| commit | 1c30462542bac8abffb4823638b6b1659c1cfcf5 (patch) | |
| tree | b86f1fc14eb0f41e224833128ecc81163227d044 /fs/xfs/xfs_trans_ail.c | |
| parent | 32ce90a4b79155a155de2b284d8b69023e5e8fea (diff) | |
| download | linux-1c30462542bac8abffb4823638b6b1659c1cfcf5.tar.gz | |
xfs: allow assigning the tail lsn with the AIL lock held
Provide a variant of xlog_assign_tail_lsn that has the AIL lock already
held. By doing so we do an additional atomic_read + atomic_set under
the lock, which comes down to two instructions.
Switch xfs_trans_ail_update_bulk and xfs_trans_ail_delete_bulk to the
new version to reduce the number of lock roundtrips, and prepare for
a new addition that would require a third lock roundtrip in
xfs_trans_ail_delete_bulk. This addition is also the reason for
slightly rearranging the conditionals and relying on xfs_log_space_wake
for checking that the filesystem has been shut down internally.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Diffstat (limited to 'fs/xfs/xfs_trans_ail.c')
| -rw-r--r-- | fs/xfs/xfs_trans_ail.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c index 1dead07f092c..77acc53f2f31 100644 --- a/fs/xfs/xfs_trans_ail.c +++ b/fs/xfs/xfs_trans_ail.c @@ -79,7 +79,7 @@ xfs_ail_check( * Return a pointer to the first item in the AIL. If the AIL is empty, then * return NULL. */ -static xfs_log_item_t * +xfs_log_item_t * xfs_ail_min( struct xfs_ail *ailp) { @@ -667,11 +667,15 @@ xfs_trans_ail_update_bulk( if (!list_empty(&tmp)) xfs_ail_splice(ailp, cur, &tmp, lsn); - spin_unlock(&ailp->xa_lock); - if (mlip_changed && !XFS_FORCED_SHUTDOWN(ailp->xa_mount)) { - xlog_assign_tail_lsn(ailp->xa_mount); + if (mlip_changed) { + if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) + xlog_assign_tail_lsn_locked(ailp->xa_mount); + spin_unlock(&ailp->xa_lock); + xfs_log_space_wake(ailp->xa_mount); + } else { + spin_unlock(&ailp->xa_lock); } } @@ -729,11 +733,15 @@ xfs_trans_ail_delete_bulk( if (mlip == lip) mlip_changed = 1; } - spin_unlock(&ailp->xa_lock); - if (mlip_changed && !XFS_FORCED_SHUTDOWN(ailp->xa_mount)) { - xlog_assign_tail_lsn(ailp->xa_mount); + if (mlip_changed) { + if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) + xlog_assign_tail_lsn_locked(ailp->xa_mount); + spin_unlock(&ailp->xa_lock); + xfs_log_space_wake(ailp->xa_mount); + } else { + spin_unlock(&ailp->xa_lock); } } |