From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joseph Qi Date: Tue, 8 Apr 2014 18:47:04 +0800 Subject: [Ocfs2-devel] [PATCH v2] ocfs2: retry once dlm_dispatch_assert_master failed with ENOMEM Message-ID: <5343D3A8.1080302@huawei.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Once dlm_dispatch_assert_master failed in dlm_master_requery_handler, the only reason is ENOMEM. Add retry logic to avoid BUG() in case of not enough memory temporarily. Signed-off-by: Joseph Qi --- fs/ocfs2/dlm/dlmrecovery.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index 7035af0..7db0465 100644 --- a/fs/ocfs2/dlm/dlmrecovery.c +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -1676,6 +1676,9 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data, unsigned int hash; int master = DLM_LOCK_RES_OWNER_UNKNOWN; u32 flags = DLM_ASSERT_MASTER_REQUERY; + int ret, retries = 0; + +#define DISPATCH_ASSERT_RETRY_TIMES 3 if (!dlm_grab(dlm)) { /* since the domain has gone away on this @@ -1685,18 +1688,30 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data, hash = dlm_lockid_hash(req->name, req->namelen); +retry: spin_lock(&dlm->spinlock); res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash); if (res) { spin_lock(&res->spinlock); master = res->owner; if (master == dlm->node_num) { - int ret = dlm_dispatch_assert_master(dlm, res, - 0, 0, flags); + ret = dlm_dispatch_assert_master(dlm, res, + 0, 0, flags); if (ret < 0) { - mlog_errno(-ENOMEM); - /* retry!? */ - BUG(); + mlog_errno(ret); + + /* ENOMEM returns, retry until + * DISPATCH_ASSERT_RETRY_TIMES reached */ + if (retries < DISPATCH_ASSERT_RETRY_TIMES) { + spin_unlock(&res->spinlock); + dlm_lockres_put(res); + spin_unlock(&dlm->spinlock); + msleep(50); + retries++; + goto retry; + } else { + BUG(); + } } } else /* put.. incase we are not the master */ dlm_lockres_put(res); -- 1.8.4.3