1. 04 May, 2016 1 commit
  2. 06 Jan, 2016 1 commit
  3. 31 Aug, 2015 1 commit
    • Guoqing Jiang's avatar
      md-cluster: fix deadlock issue on message lock · 66099bb0
      Guoqing Jiang authored
      There is problem with previous communication mechanism, and we got below
      deadlock scenario with cluster which has 3 nodes.
      
      	Sender                	    Receiver        		Receiver
      
      	token(EX)
             message(EX)
            writes message
         downconverts message(CR)
            requests ack(EX)
      		                  get message(CR)            gets message(CR)
                      		  reads message                reads message
      		               requests EX on message    requests EX on message
      
      To fix this problem, we do the following changes:
      
      1. the sender downconverts MESSAGE to CW rather than CR.
      2. and the receiver request PR lock not EX lock on message.
      
      And in case we failed to down-convert EX to CW on message, it is better to
      unlock message otherthan still hold the lock.
      Reviewed-by: 's avatarGoldwyn Rodrigues <rgoldwyn@suse.com>
      Signed-off-by: 's avatarLidong Zhong <ldzhong@suse.com>
      Signed-off-by: 's avatarGuoqing Jiang <gqjiang@suse.com>
      Signed-off-by: 's avatarNeilBrown <neilb@suse.com>
      66099bb0
  4. 23 Feb, 2015 1 commit