• S
    GFS2: Fix deadlock on journal flush · d8348de0
    Steven Whitehouse 提交于
    This patch fixes a deadlock when the journal is flushed and there
    are dirty inodes other than the one which caused the journal flush.
    Originally the journal flushing code was trying to obtain the
    transaction glock while running the flush code for an inode glock.
    We no longer require the transaction glock at this point in time
    since we know that any attempt to get the transaction glock from
    another node will result in a journal flush. So if we are flushing
    the journal, we can be sure that the transaction lock is still
    cached from when the transaction was started.
    
    By inlining a version of gfs2_trans_begin() (minus the bit which
    gets the transaction glock) we can avoid the deadlock problems
    caused if there is a demote request queued up on the transaction
    glock.
    
    In addition I've also moved the umount rwsem so that it covers
    the glock workqueue, since it all demotions are done by this
    workqueue now. That fixes a bug on umount which I came across
    while fixing the original problem.
    Reported-by: NDavid Teigland <teigland@redhat.com>
    Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
    d8348de0
trans.c 4.2 KB