Hi Jiufei, I didn't find other solution for this issue. You can go with yours. Looks like your second one is more straightforward, there deref work can be removed.
Thanks, Junxiao. On 01/11/2016 10:46 AM, xuejiufei wrote: > Hi all, > We have found a race between refmap setting and clearing which > will cause the lock resource on master is freed before other nodes > purge it. > > Node 1 Node 2(master) > dlm_do_master_request > dlm_master_request_handler > -> dlm_lockres_set_refmap_bit > call dlm_purge_lockres after unlock > dlm_deref_handler > -> find lock resource is in > DLM_LOCK_RES_SETREF_INPROG state, > so dispatch a deref work > dlm_purge_lockres succeed. > > dlm_do_master_request > dlm_master_request_handler > -> dlm_lockres_set_refmap_bit > > deref work trigger, call > dlm_lockres_clear_refmap_bit > to clear Node 1 from refmap > > Now Node 2 can purge the lock resource but the owner of lock resource > on Node 1 is still Node 2 which may trigger BUG if the lock resource > is $RECOVERY or other problems. > > We have discussed 2 solutions: > 1)The master return error to Node 1 if the DLM_LOCK_RES_SETREF_INPROG > is set. Node 1 will not retry and master send another message to Node 1 > after clearing the refmap. Node 1 can purge the lock resource after the > refmap on master is cleared. > 2) The master return error to Node 1 if the DLM_LOCK_RES_SETREF_INPROG > is set, and Node 1 will retry to deref the lockres. > > Does anybody has better ideas? > > Thanks, > --Jiufei > _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel
