From 39e2defe73106ca2e1c85e5286038a0a13f49513 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 3 Dec 2008 12:20:28 +0100 Subject: reduce l_icloglock roundtrips All but one caller of xlog_state_want_sync drop and re-acquire l_icloglock around the call to it, just so that xlog_state_want_sync can acquire and drop it. Move all lock operation out of l_icloglock and assert that the lock is held when it is called. Note that it would make sense to extende this scheme to xlog_state_release_iclog, but the locking in there is more complicated and we'd like to keep the atomic_dec_and_lock optmization for those callers not having l_icloglock yet. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Signed-off-by: Niv Sardi --- fs/xfs/xfs_log.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'fs') diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index aadaa1472f69..f4726f702a9e 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -729,8 +729,8 @@ xfs_log_unmount_write(xfs_mount_t *mp) spin_lock(&log->l_icloglock); iclog = log->l_iclog; atomic_inc(&iclog->ic_refcnt); - spin_unlock(&log->l_icloglock); xlog_state_want_sync(log, iclog); + spin_unlock(&log->l_icloglock); error = xlog_state_release_iclog(log, iclog); spin_lock(&log->l_icloglock); @@ -767,9 +767,9 @@ xfs_log_unmount_write(xfs_mount_t *mp) spin_lock(&log->l_icloglock); iclog = log->l_iclog; atomic_inc(&iclog->ic_refcnt); - spin_unlock(&log->l_icloglock); xlog_state_want_sync(log, iclog); + spin_unlock(&log->l_icloglock); error = xlog_state_release_iclog(log, iclog); spin_lock(&log->l_icloglock); @@ -1984,7 +1984,9 @@ xlog_write(xfs_mount_t * mp, if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) { xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); record_cnt = data_cnt = 0; + spin_lock(&log->l_icloglock); xlog_state_want_sync(log, iclog); + spin_unlock(&log->l_icloglock); if (commit_iclog) { ASSERT(flags & XLOG_COMMIT_TRANS); *commit_iclog = iclog; @@ -3193,7 +3195,7 @@ try_again: STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog) { - spin_lock(&log->l_icloglock); + ASSERT(spin_is_locked(&log->l_icloglock)); if (iclog->ic_state == XLOG_STATE_ACTIVE) { xlog_state_switch_iclogs(log, iclog, 0); @@ -3201,10 +3203,7 @@ xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog) ASSERT(iclog->ic_state & (XLOG_STATE_WANT_SYNC|XLOG_STATE_IOERROR)); } - - spin_unlock(&log->l_icloglock); -} /* xlog_state_want_sync */ - +} /***************************************************************************** -- cgit v1.2.3