1. 05 Feb, 2007 40 commits
    • David Teigland's avatar
      [DLM] saved dlm message can be dropped · 8fd3a98f
      David Teigland authored
      dlm_receive_message() returns 0 instead of returning 'error'.  What would
      happen is that process_requestqueue would take a saved message off the
      requestqueue and call receive_message on it.  receive_message would then
      see that recovery had been aborted, set error to EINTR, and 'goto out',
      expecting that the error would be returned.  Instead, 0 was always
      returned, so process_requestqueue would think that the message had been
      processed and delete it instead of saving it to process next time.  This
      means the message (usually an unlock in my tests) would be lost.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      8fd3a98f
    • Patrick Caulfield's avatar
      [DLM] Make sock_sem into a mutex · f1f1c1cc
      Patrick Caulfield authored
      Now that there can be multiple dlm_recv threads running we need to prevent two
      recvs running for the same connection - it's unlikely but it can happen and it
      causes message corruption.
      Signed-Off-By: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      f1f1c1cc
    • Steven Whitehouse's avatar
      [GFS2] Fix typo in glock.c · d043e190
      Steven Whitehouse authored
      This is a one letter typo fix in glock.c, spotted by Rob Kenna.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      d043e190
    • Eric Sandeen's avatar
      [GFS2] use CURRENT_TIME_SEC instead of get_seconds in gfs2 · ddfe0627
      Eric Sandeen authored
      I was looking something else up and came across this...
      
      I don't honestly have a good reason to change it other than to make it
      like every other Linux filesystem in this regard.  ;-)  It doesn't
      functionally change anything, but makes some lines shorter. :)
      
      I'm also curious; why does gfs2 have 64-bits of on-disk timestamps, but
      not in timespec_t format, and only stores second resolutions?  Seems like
      you're halfway to sub-second resolutions already.
      
      I suppose if that gets implemented then all of the below should
      instead be CURRENT_TIME not CURRENT_TIME_SEC.
      Signed-off-by: default avatarEric Sandeen <sandeen@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      ddfe0627
    • Steven Whitehouse's avatar
      [GFS2] Compile fix for glock.c · 90101c31
      Steven Whitehouse authored
      This one liner got missed from the previous patch.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      90101c31
    • Steven Whitehouse's avatar
      [GFS2] Remove queue_empty() function · 12132933
      Steven Whitehouse authored
      This function is not longer required since we do not do recursive
      locking in the glock layer. As a result all its callers can be
      replaceed with list_empty() calls.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      12132933
    • Patrick Caulfield's avatar
      [DLM] fix lowcomms receiving · bd44e2b0
      Patrick Caulfield authored
      This patch fixes a bug whereby data on a newly accepted connection would be
      ignored if it arrived soon after the accept.
      Signed-Off-By: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      bd44e2b0
    • Steven Whitehouse's avatar
      [GFS2] Tidy up glops calls · b5d32bea
      Steven Whitehouse authored
      This patch doesn't make any changes to the ordering of the various
      operations related to glocking, but it does tidy up the calls to the
      glops.c functions to make the structure more obvious.
      
      The two functions: gfs2_glock_xmote_th() and gfs2_glock_drop_th() can be
      made static within glock.c since they are called by every set of glock
      operations. The xmote_th and drop_th glock operations are then made
      conditional upon those two routines existing and called from the
      previously mentioned functions in glock.c respectively.
      
      Also it can be seen that the go_sync operation isn't needed since it can
      easily be replaced by calls to xmote_bh and drop_bh respectively. This
      results in no longer (confusingly) calling back into routines in glock.c
      from glops.c and also reducing the glock operations by one member.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      b5d32bea
    • Patrick Caulfield's avatar
      [DLM] lowcomms tidy · f2f5095f
      Patrick Caulfield authored
      This patch removes some redundant fields from the connection structure and adds
      some lockdep annotation to remove spurious warnings.
      Signed-Off-By: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      f2f5095f
    • Steven Whitehouse's avatar
      [GFS2] Remove local exclusive glock mode · 1c0f4872
      Steven Whitehouse authored
      Here is a patch for GFS2 to remove the local exclusive flag. In
      the places it was used, mutex's are always held earlier in the
      call path, so it appears redundant in the LM_ST_SHARED case.
      
      Also, the GFS2 holders were setting local exclusive in any case where
      the requested lock was LM_ST_EXCLUSIVE. So the other places in the glock
      code where the flag was tested have been replaced with tests for the
      lock state being LM_ST_EXCLUSIVE in order to ensure the logic is the
      same as before (i.e. LM_ST_EXCLUSIVE is always locally exclusive as well
      as globally exclusive).
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      1c0f4872
    • Steven Whitehouse's avatar
      [GFS2] Remove unused go_callback operation · 6bd9c8c2
      Steven Whitehouse authored
      This is never used, so we might as well remove it.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      6bd9c8c2
    • Steven Whitehouse's avatar
      [GFS2] Remove the "greedy" function from glock.[ch] · e5dab552
      Steven Whitehouse authored
      The "greedy" code was an attempt to retain glocks for a minimum length
      of time when they relate to mmap()ed files. The current implementation
      of this feature is not, however, ideal in that it required allocating
      memory in order to do this and its overly complicated.
      
      It also misses the mark by ignoring the other I/O operations which are
      just as likely to suffer from the same problem. So the plan is to remove
      this now and then add the functionality back as part of the glock state
      machine at a later date (and thus take into account all the possible
      users of this feature)
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      e5dab552
    • Steven Whitehouse's avatar
      [GFS2] Shrink gfs2_inode memory by half · fee852e3
      Steven Whitehouse authored
      Here is something I spotted (while looking for something entirely
      different) the other day.
      
      Rather than using a completion in each and every struct gfs2_holder,
      this removes it in favour of hashed wait queues, thus saving a
      considerable amount of memory both on the stack (where a number of
      gfs2_holder structures are allocated) and in particular in the
      gfs2_inode which has 8 gfs2_holder structures embedded within it.
      
      As a result on x86_64 the gfs2_inode shrinks from 2488 bytes to
      1912 bytes, a saving of 576 bytes per inode (no thats not a typo!).
      In actual practice we get a much better result than that since
      now that a gfs2_inode is under the 2048 byte barrier, we get two
      per 4k slab page effectively halving the amount of memory required
      to store gfs2_inodes.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      fee852e3
    • Steven Whitehouse's avatar
      [GFS2] Remove max_atomic_write tunable · 330005c2
      Steven Whitehouse authored
      This removes an unused sysfs tunable parameter.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      330005c2
    • Steven Whitehouse's avatar
      [GFS2] Clean up/speed up readdir · 3699e3a4
      Steven Whitehouse authored
      This removes the extra filldir callback which gfs2 was using to
      enclose an attempt at readahead for inodes during readdir. The
      code was too complicated and also hurts performance badly in the
      case that the getdents64/readdir call isn't being followed by
      stat() and it wasn't even getting it right all the time when it
      was.
      
      As a result, on my test box an "ls" of a directory containing 250000
      files fell from about 7mins (freshly mounted, so nothing cached) to
      between about 15 to 25 seconds. When the directory content was cached,
      the time taken fell from about 3mins to about 4 or 5 seconds.
      
      Interestingly in the cached case, running "ls -l" once reduced the time
      taken for subsequent runs of "ls" to about 6 secs even without this
      patch. Now it turns out that there was a special case of glocks being
      used for prefetching the metadata, but because of the timeouts for these
      locks (set to 10 secs) the metadata was being timed out before it was
      being used and this the prefetch code was constantly trying to prefetch
      the same data over and over.
      
      Calling "ls -l" meant that the inodes were brought into memory and once
      the inodes are cached, the glocks are not disposed of until the inodes
      are pushed out of the cache, thus extending the lifetime of the glocks,
      and thus bringing down the time for subsequent runs of "ls"
      considerably.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      3699e3a4
    • Steven Whitehouse's avatar
      [GFS2] Add writepages for "data=writeback" mounts · a8d638e3
      Steven Whitehouse authored
      It occurred to me that although a gfs2 specific writepages for ordered
      writes and journaled data would be tricky, by hooking writepages only
      for "data=writeback" mounts we could take advantage of not needing
      buffer heads (we don't use them on the read side, nor have we for some
      time) and create much larger I/Os for the block layer.
      
      Using blktrace both before and after, its possible to see that for large
      I/Os, most of the requests generated through writepages are now 1024
      sectors after this patch is applied as opposed to 8 sectors before.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      a8d638e3
    • David Teigland's avatar
      [DLM] fix master recovery · 222d3960
      David Teigland authored
      If master recovery happens on an rsb in one recovery sequence, then that
      sequence is aborted before lock recovery happens, then in the next
      sequence, we rely on the previous master recovery (which may now be
      invalid due to another node ignoring a lookup result) and go on do to the
      lock recovery where we get stuck due to an invalid master value.
      
       recovery cycle begins: master of rsb X has left
       nodes A and B send node C an rcom lookup for X to find the new master
       C gets lookup from B first, sets B as new master, and sends reply back to B
       C gets lookup from A next, and sends reply back to A saying B is master
       A gets lookup reply from C and sets B as the new master in the rsb
       recovery cycle on A, B and C is aborted to start a new recovery
       B gets lookup reply from C and ignores it since there's a new recovery
       recovery cycle begins: some other node has joined
       B doesn't think it's the master of X so it doesn't rebuild it in the directory
       C looks up the master of X, no one is master, so it becomes new master
       B looks up the master of X, finds it's C
       A believes that B is the master of X, so it sends its lock to B
       B sends an error back to A
       A resends
       this repeats forever, the incorrect master value on A is never corrected
      
      The fix is to do master recovery on an rsb that still has the NEW_MASTER
      flag set from an earlier recovery sequence, and therefore didn't complete
      lock recovery.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      222d3960
    • David Teigland's avatar
      [DLM] fix user unlocking · a1bc86e6
      David Teigland authored
      When a user process exits, we clear all the locks it holds.  There is a
      problem, though, with locks that the process had begun unlocking before it
      exited.  We couldn't find the lkb's that were in the process of being
      unlocked remotely, to flag that they are DEAD.  To solve this, we move
      lkb's being unlocked onto a new list in the per-process structure that
      tracks what locks the process is holding.  We can then go through this
      list to flag the necessary lkb's when clearing locks for a process when it
      exits.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      a1bc86e6
    • Patrick Caulfield's avatar
      [DLM] Use workqueues for dlm lowcomms · 1d6e8131
      Patrick Caulfield authored
      This patch converts the DLM TCP lowcomms to use workqueues rather than using its
      own daemon functions. Simultaneously removing a lot of code and making it more
      scalable on multi-processor machines.
      Signed-Off-By: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      1d6e8131
    • Adrian Bunk's avatar
      [GFS2] make gfs2_change_nlink_i() static · 03dc6a53
      Adrian Bunk authored
      On Thu, Jan 11, 2007 at 10:26:27PM -0800, Andrew Morton wrote:
      >...
      > Changes since 2.6.20-rc3-mm1:
      >...
      >  git-gfs2-nmw.patch
      >...
      >  git trees
      >...
      
      This patch makes the needlessly globlal gfs2_change_nlink_i() static.
      Signed-off-by: default avatarAdrian Bunk <bunk@stusta.de>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      03dc6a53
    • Robert Peterson's avatar
      [GFS2] gfs2 knows of directories which it chooses not to display · 70831465
      Robert Peterson authored
      This is for Red Hat bugzilla bug bz #222302:
      
      Moving a virtual IP from node to node between two NFS-over-GFS2
      servers was causing one of the GFS2 servers to become confused and
      reference a deleted inode.  The problem was due to vfs dentries that did
      not reference the gfs2_dops and therefore didn't call the gfs2 revalidate
      code to revalidate a dentry after a directory had been deleted & recreated.
      This patch is a crosswrite from a RHEL4 bug found in GFS1 as
      bz #190756 and it is against the latest -nmw git tree.
      Signed-off-by: default avatarRobert Peterson <rpeterso@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      70831465
    • David Teigland's avatar
      [DLM] expose dlm_config_info fields in configfs · d200778e
      David Teigland authored
      Make the dlm_config_info values readable and writeable via configfs
      entries.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      d200778e
    • David Teigland's avatar
      [DLM] add config entry to enable log_debug · 99fc6487
      David Teigland authored
      Add a new dlm_config_info field to enable log_debug output and change
      log_debug() to use it.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      99fc6487
    • David Teigland's avatar
      [DLM] rename dlm_config_info fields · 68c817a1
      David Teigland authored
      Add a "ci_" prefix to the fields in the dlm_config_info struct so that we
      can use macros to add configfs functions to access them (in a later
      patch).  No functional changes in this patch, just naming changes.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      68c817a1
    • David Teigland's avatar
      [DLM] change some log_error to log_debug · 8ec68867
      David Teigland authored
      Some common, non-error messages should use log_debug instead of log_error
      so they can be turned off.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      8ec68867
    • S. Wendy Cheng's avatar
      [GFS2] Fix gfs2_rename deadlock · 87d21e07
      S. Wendy Cheng authored
      Second round of gfs2_rename lock re-ordering to allow Anaconda adding
      root partition on top of gfs2. Previous to this patch the recursive
      lock detector in glock.c can be triggered due to attempting to lock
      the rgrp twice. This fixes it by checking to see whether the rgrp
      is already locked.
      
      This fixes Red Hat bugzilla #221237
      Signed-off-by: default avatarS. Wendy Cheng <wcheng@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      87d21e07
    • Russell Cattelan's avatar
      [GFS2] BZ 217008 fsfuzzer fix. · 6c93fd1e
      Russell Cattelan authored
      Update the quilt header comments to match the
      code changes.
      
      Change gfs2_lookup_simple to return an error in the case
      of a NULL inode.
      The callers of gfs2_lookup_simple do not check for NULL
      in the no entry case and such would end up dereferencing a NULL ptr.
      
      This fixes:
      http://projects.info-pull.com/mokb/MOKB-15-11-2006.htmlSigned-off-by: default avatarRussell Cattelan <cattelan@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      6c93fd1e
    • Steven Whitehouse's avatar
      [GFS2] Fix ordering of page disposal vs. glock_dq · 49686f71
      Steven Whitehouse authored
      In case of unlinked files with dirty pages GFS2 wasn't clearing
      the pages in quite the right order. This patch clears the pages
      earlier (before the qlock_dq) to avoid the situation that the
      release of the glock results in attempting to write back data that
      has already been deallocated.
      
      This fixes Red Hat bugzilla: #220117
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      49686f71
    • Patrick Caulfield's avatar
      [DLM] Fix spin lock already unlocked bug · 4edde74e
      Patrick Caulfield authored
      I just noticed this message when testing some other changes I'd made to
      lowcomms (to use workqueues) but the problem seems to be in the current
      git trees too. I'm amazed no-one has seen it.
      
          BUG: spinlock already unlocked on CPU#1, dlm_recoverd/16868
      Signed-Off-By: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      4edde74e
    • Patrick Caulfield's avatar
      [DLM] Fix schedule() calls · 3fb4a251
      Patrick Caulfield authored
      I was a little over-enthusiastic turning schedule() calls int cond_sched() when fixing the DLM for Andrew Morton.
      
      These four should really be calls to schedule() or the dlm can busy-wait.
      Signed-Off-By: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      3fb4a251
    • S. Wendy Cheng's avatar
      [GFS2] Fix change nlink deadlock · 5509826f
      S. Wendy Cheng authored
      Bugzilla 215088
      
      Fix deadlock in gfs2_change_nlink() while installing RHEL5 into GFS2
      partition. The gfs2_rename() apparently needs block allocation for the
      new name (into the directory) where it requires rg locks. At the same
      time, while updating the nlink count for the replaced file,
      gfs2_change_nlink() tries to return the inode meta-data back to resource
      group where it needs rg locks too. Our logic doesn't allow process to
      acquire these locks recursively by the same process  (RHEL installer)
      that results a BUG call. This only happens within rename code path and
      only if the destination file exists before the rename operation.
      Signed-off-by: default avatarS. Wendy Cheng <wcheng@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      5509826f
    • Steven Whitehouse's avatar
      [GFS2] Fail over to readpage for stuffed files · e1d5b18a
      Steven Whitehouse authored
      This is partially derrived from a patch written by Russell Cattelan.
      It fixes a bug where there is a race between readpages and truncate
      by ignoring readpages for stuffed files. This is ok because a stuffed
      file will never be more than one block (minus sizeof(struct gfs2_dinode))
      in size and block size is always less than page size, so we do not lose
      anything efficiency-wise by not doing readahead for stuffed files. They
      will have already been "read ahead" by the action of reading the inode
      in, in the first place.
      
      This is the remaining part of the fix for Red Hat bugzilla #218966
      which had not yet made it upstream.
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      Cc: Russell Cattelan <cattelan@redhat.com>
      e1d5b18a
    • Steven Whitehouse's avatar
      [GFS2] Fix DIO deadlock · c7b33834
      Steven Whitehouse authored
      This patch fixes Red Hat bugzilla #212627 in which a deadlock occurs
      due to trying to take the i_mutex while holding a glock. The correct
      locking order is defined as i_mutex -> glock in all cases.
      
      I've left dealing with allocating writes. I know that we need to do
      that, but for now this should do the trick. We don't need to take the
      i_mutex on write, because the VFS has already taken it for us. On read
      we don't need it since the glock is enough protection. The reason that
      I've made some of the checks into a separate function is that we'll need
      to do the checks again in the allocating write case eventually, so this
      is partly in preparation for this. Likewise the return value test of !=
      1 might look a bit odd and thats because we'll need a third return value
      in case of requiring an allocation.
      
      I've made the change to deferred mode on the glock to ensure flushing
      read caches on other nodes. I notice that (using blktrace to look at
      whats going on) we appear to do a better job of large I/Os than ext3
      after this patch (in terms of not splitting up the I/Os).
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      Cc: Wendy Cheng <wcheng@redhat.com>
      c7b33834
    • Adrian Bunk's avatar
      [DLM] fs/dlm/lowcomms-tcp.c: remove 2 functions · 927255f0
      Adrian Bunk authored
      Remove the following unused functions:
      
      - lowcomms_send_message()
      - lowcomms_max_buffer_size()
      Signed-off-by: default avatarAdrian Bunk <bunk@stusta.de>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarPatrick Caulfield <pcaulfie@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      927255f0
    • David Teigland's avatar
      [DLM] fix lost flags in stub replies · 075529b5
      David Teigland authored
      When the dlm fakes an unlock/cancel reply from a failed node using a stub
      message struct, it wasn't setting the flags in the stub message.  So, in
      the process of receiving the fake message the lkb flags would be updated
      and cleared from the zero flags in the message.  The problem observed in
      tests was the loss of the USER flag which caused the dlm to think a user
      lock was a kernel lock and subsequently fail an assertion checking the
      validity of the ast/callback field.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      075529b5
    • David Teigland's avatar
      [DLM] fix receive_request() lvb copying · 8d07fd50
      David Teigland authored
      LVB's are not sent as part of new requests, but the code receiving the
      request was copying data into the lvb anyway.  The space in the message
      where it mistakenly thought the lvb lived actually contained the resource
      name, so it wound up incorrectly copying this name data into the lvb.  Fix
      is to just create the lvb, not copy junk into it.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      8d07fd50
    • David Teigland's avatar
      [DLM] fix send_args() lvb copying · da49f36f
      David Teigland authored
      The send_args() function is used to copy parameters into a message for a
      number different message types.  Only some of those types are set up
      beforehand (in create_message) to include space for sending lvb data.
      send_args was wrongly copying the lvb for all message types as long as the
      lock had an lvb.  This means that the lvb data was being written past the
      end of the message into unknown space.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      da49f36f
    • David Teigland's avatar
      [DLM] add version check · 9e971b71
      David Teigland authored
      Check if we receive a message from another lockspace member running a
      version of the dlm with an incompatible inter-node message protocol.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      9e971b71
    • David Teigland's avatar
      [DLM] fix old rcom messages · 38aa8b0c
      David Teigland authored
      A reply to a recovery message will often be received after the relevant
      recovery sequence has aborted and the next recovery sequence has begun.
      We need to ignore replies to these old messages from the previous
      recovery.  There's already a way to do this for synchronous recovery
      requests using the rc_id number, but not for async.
      
      Each recovery sequence already has a locally unique sequence number
      associated with it.  This patch adds a field to the rcom (recovery
      message) structure where this recovery sequence number can be placed,
      rc_seq.  When a node sends a reply to a recovery request, it copies the
      rc_seq number it received into rc_seq_reply.  When the first node receives
      the reply to its recovery message, it will check whether rc_seq_reply
      matches the current recovery sequence number, ls_recover_seq, and if not
      then it ignores the old reply.
      
      An old, inadequate approach to filtering out old replies (checking if the
      current stage of recovery has moved back to the start) has been removed
      from two spots.
      
      The protocol version number is changed to reflect the different rcom
      structures.
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      38aa8b0c
    • David Teigland's avatar
      [DLM] fix resend rcom lock · dc200a88
      David Teigland authored
      There's a chance the new master of resource hasn't learned it's the new
      master before another node sends it a lock during recovery.  The node
      sending the lock needs to resend if this happens.
      
      - A sends a master lookup for resource R to C
      - B sends a master lookup for resource R to C
      - C receives A's lookup, assigns A to be master of R and
        sends a reply back to A
      - C receives B's lookup and sends a reply back to B saying
        that A is the master
      - B receives lookup reply from C and sends its lock for R to A
      - A receives lock from B, doesn't think it's the master of R
        and sends an error back to B
      - A receives lookup reply from C and becomes master of R
      - B gets error back from A and resends its lock back to A
        (this resending is what this patch does)
      - A receives lock from B, it now sees it's the master of R
        and takes the lock
      Signed-off-by: default avatarDavid Teigland <teigland@redhat.com>
      Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      dc200a88