From 114d23aae51233b2bc62d8e2a632bcb55de1953d Mon Sep 17 00:00:00 2001 From: David Chinner Date: Thu, 10 Apr 2008 12:18:39 +1000 Subject: [XFS] Per iclog callback chain lock Rather than use the icloglock for protecting the iclog completion callback chain, use a new per-iclog lock so that walking the callback chain doesn't require holding a global lock. This reduces contention on the icloglock during transaction commit and log I/O completion by reducing the number of times we need to hold the global icloglock during these operations. SGI-PV: 978729 SGI-Modid: xfs-linux-melb:xfs-kern:30770a Signed-off-by: David Chinner Signed-off-by: Christoph Hellwig Signed-off-by: Lachlan McIlroy --- fs/xfs/xfs_log.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) (limited to 'fs/xfs/xfs_log.c') diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index 1fa980933895..7a5b12d93537 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -397,12 +397,10 @@ xfs_log_notify(xfs_mount_t *mp, /* mount of partition */ void *iclog_hndl, /* iclog to hang callback off */ xfs_log_callback_t *cb) { - xlog_t *log = mp->m_log; xlog_in_core_t *iclog = (xlog_in_core_t *)iclog_hndl; int abortflg; - cb->cb_next = NULL; - spin_lock(&log->l_icloglock); + spin_lock(&iclog->ic_callback_lock); abortflg = (iclog->ic_state & XLOG_STATE_IOERROR); if (!abortflg) { ASSERT_ALWAYS((iclog->ic_state == XLOG_STATE_ACTIVE) || @@ -411,7 +409,7 @@ xfs_log_notify(xfs_mount_t *mp, /* mount of partition */ *(iclog->ic_callback_tail) = cb; iclog->ic_callback_tail = &(cb->cb_next); } - spin_unlock(&log->l_icloglock); + spin_unlock(&iclog->ic_callback_lock); return abortflg; } /* xfs_log_notify */ @@ -1257,6 +1255,8 @@ xlog_alloc_log(xfs_mount_t *mp, iclog->ic_size = XFS_BUF_SIZE(bp) - log->l_iclog_hsize; iclog->ic_state = XLOG_STATE_ACTIVE; iclog->ic_log = log; + atomic_set(&iclog->ic_refcnt, 0); + spin_lock_init(&iclog->ic_callback_lock); iclog->ic_callback_tail = &(iclog->ic_callback); iclog->ic_datap = (char *)iclog->hic_data + log->l_iclog_hsize; @@ -1987,7 +1987,7 @@ xlog_state_clean_log(xlog_t *log) if (iclog->ic_state == XLOG_STATE_DIRTY) { iclog->ic_state = XLOG_STATE_ACTIVE; iclog->ic_offset = 0; - iclog->ic_callback = NULL; /* don't need to free */ + ASSERT(iclog->ic_callback == NULL); /* * If the number of ops in this iclog indicate it just * contains the dummy transaction, we can @@ -2190,37 +2190,40 @@ xlog_state_do_callback( be64_to_cpu(iclog->ic_header.h_lsn); spin_unlock(&log->l_grant_lock); - /* - * Keep processing entries in the callback list - * until we come around and it is empty. We - * need to atomically see that the list is - * empty and change the state to DIRTY so that - * we don't miss any more callbacks being added. - */ - spin_lock(&log->l_icloglock); } else { + spin_unlock(&log->l_icloglock); ioerrors++; } - cb = iclog->ic_callback; + /* + * Keep processing entries in the callback list until + * we come around and it is empty. We need to + * atomically see that the list is empty and change the + * state to DIRTY so that we don't miss any more + * callbacks being added. + */ + spin_lock(&iclog->ic_callback_lock); + cb = iclog->ic_callback; while (cb) { iclog->ic_callback_tail = &(iclog->ic_callback); iclog->ic_callback = NULL; - spin_unlock(&log->l_icloglock); + spin_unlock(&iclog->ic_callback_lock); /* perform callbacks in the order given */ for (; cb; cb = cb_next) { cb_next = cb->cb_next; cb->cb_func(cb->cb_arg, aborted); } - spin_lock(&log->l_icloglock); + spin_lock(&iclog->ic_callback_lock); cb = iclog->ic_callback; } loopdidcallbacks++; funcdidcallbacks++; + spin_lock(&log->l_icloglock); ASSERT(iclog->ic_callback == NULL); + spin_unlock(&iclog->ic_callback_lock); if (!(iclog->ic_state & XLOG_STATE_IOERROR)) iclog->ic_state = XLOG_STATE_DIRTY; -- cgit v1.2.3