16 Jul, 2011

1 commit

  • Instead of creating our own kthread (dlm_astd) to deliver
    callbacks for all lockspaces, use a per-lockspace workqueue
    to deliver the callbacks. This eliminates complications and
    slowdowns from many lockspaces sharing the same thread.

    Signed-off-by: David Teigland

    David Teigland
     

11 Mar, 2011

1 commit

  • Change how callbacks are recorded for locks. Previously, information
    about multiple callbacks was combined into a couple of variables that
    indicated what the end result should be. In some situations, we
    could not tell from this combined state what the exact sequence of
    callbacks were, and would end up either delivering the callbacks in
    the wrong order, or suppress redundant callbacks incorrectly. This
    new approach records all the data for each callback, leaving no
    uncertainty about what needs to be delivered.

    Signed-off-by: David Teigland

    David Teigland
     

25 Feb, 2010

1 commit

  • When both blocking and completion callbacks are queued for lock,
    the dlm would always deliver the completion callback (cast) first.
    In some cases the blocking callback (bast) is queued before the
    cast, though, and should be delivered first. This patch keeps
    track of the order in which they were queued and delivers them
    in that order.

    This patch also keeps track of the granted mode in the last cast
    and eliminates the following bast if the bast mode is compatible
    with the preceding cast mode. This happens when a remotely mastered
    lock is demoted, e.g. EX->NL, in which case the local node queues
    a cast immediately after sending the demote message. In this way
    a cast can be queued for a mode, e.g. NL, that makes an in-transit
    bast extraneous.

    Signed-off-by: David Teigland

    David Teigland
     

24 Dec, 2008

1 commit

  • The lkb bastmode value is set in the context of processing the
    lock, and read by the dlm_astd thread. Because it's accessed
    in these two separate contexts, the writing/reading ought to
    be done under a lock. This is simple to do by setting it and
    reading it when the lkb is added to and removed from dlm_astd's
    callback list which is properly locked.

    Signed-off-by: David Teigland

    David Teigland
     

18 Jan, 2006

1 commit

  • This is the core of the distributed lock manager which is required
    to use GFS2 as a cluster filesystem. It is also used by CLVM and
    can be used as a standalone lock manager independantly of either
    of these two projects.

    It implements VAX-style locking modes.

    Signed-off-by: David Teigland
    Signed-off-by: Steve Whitehouse

    David Teigland