02 Apr, 2011

1 commit


22 Apr, 2008

1 commit


04 Feb, 2008

1 commit

  • * check that length is large enough to cover the non-variable part of message or
    rcom resp. (after checking that it's large enough to cover the header, of
    course).

    * kill more pointless casts

    Signed-off-by: Al Viro
    Signed-off-by: David Teigland

    Al Viro
     

31 Jan, 2008

1 commit

  • To prevent the master of an rsb from changing rapidly, an unused rsb is kept
    on the "toss list" for a period of time to be reused. The toss list was
    being cleared completely for each recovery, which is unnecessary. Much of
    the benefit of the toss list can be maintained if nodes keep rsb's in their
    toss list that they are the master of. These rsb's need to be included
    when the resource directory is rebuilt during recovery.

    Signed-off-by: David Teigland

    David Teigland
     

10 Oct, 2007

1 commit

  • Introduce a per-lockspace rwsem that's held in read mode by dlm_recv
    threads while working in the dlm. This allows dlm_recv activity to be
    suspended when the lockspace transitions to, from and between recovery
    cycles.

    The specific bug prompting this change is one where an in-progress
    recovery cycle is aborted by a new recovery cycle. While dlm_recv was
    processing a recovery message, the recovery cycle was aborted and
    dlm_recoverd began cleaning up. dlm_recv decremented recover_locks_count
    on an rsb after dlm_recoverd had reset it to zero. This is fixed by
    suspending dlm_recv (taking write lock on the rwsem) before aborting the
    current recovery.

    The transitions to/from normal and recovery modes are simplified by using
    this new ability to block dlm_recv. The switch from normal to recovery
    mode means dlm_recv goes from processing locking messages, to saving them
    for later, and vice versa. Races are avoided by blocking dlm_recv when
    setting the flag that switches between modes.

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

    David Teigland
     

09 Jul, 2007

4 commits

  • Add a function that can be used through libdlm by a system daemon to cancel
    another process's deadlocked lock. A completion ast with EDEADLK is returned
    to the process waiting for the lock.

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

    David Teigland
     
  • Change the user/kernel device interface used by libdlm:
    - Add ability for userspace to check the version of the interface. libdlm
    can now adapt to different versions of the kernel interface.
    - Increase the size of the flags passed in a lock request so all possible
    flags can be used from userspace.
    - Add an opaque "xid" value for each lock. This "transaction id" will be
    used later to associate locks with each other during deadlock detection.
    - Add a "timeout" value for each lock. This is used along with the
    DLM_LKF_TIMEOUT flag.

    Also, remove a fragment of unused code in device_read().

    This patch requires updating libdlm which is backward compatible with
    older kernels.

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

    David Teigland
     
  • New features: lock timeouts and time warnings. If the DLM_LKF_TIMEOUT
    flag is set, then the request/conversion will be canceled after waiting
    the specified number of centiseconds (specified per lock). This feature
    is only available for locks requested through libdlm (can be enabled for
    kernel dlm users if there's a use for it.)

    If the new DLM_LSFL_TIMEWARN flag is set when creating the lockspace, then
    a warning message will be sent to userspace (using genetlink) after a
    request/conversion has been waiting for a given number of centiseconds
    (configurable per node). The time warnings will be used in the future
    to do deadlock detection in userspace.

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

    David Teigland
     
  • Don't let dlm_scand run during recovery since it may try to do a resource
    directory removal while the directory nodes are changing.

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

    David Teigland
     

01 May, 2007

1 commit


21 Aug, 2006

1 commit

  • Introduce new function dlm_dump_rsb() to call within assertions instead of
    dlm_print_rsb(). The new function dumps info about all locks on the rsb
    in addition to rsb details.

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

    David Teigland
     

13 Jul, 2006

1 commit

  • This changes the way the dlm handles user locks. The core dlm is now
    aware of user locks so they can be dealt with more efficiently. There is
    no more dlm_device module which previously managed its own duplicate copy
    of every user lock.

    Signed-off-by: Patrick Caulfield
    Signed-off-by: David Teigland
    Signed-off-by: Steven Whitehouse

    David Teigland
     

03 May, 2006

1 commit

  • In dlm_grant_after_purge() we were holding a hash table read_lock while
    calling put_rsb() which potentially removes the rsb from the hash table,
    taking the same lock in write. Fix this by flagging rsb's ahead of time
    that have been purged. Then iteratively read_lock the hash table, find a
    flagged rsb, unlock, process rsb.

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

    David Teigland
     

20 Jan, 2006

1 commit


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