1. 16 5月, 2017 1 次提交
  2. 02 5月, 2017 2 次提交
  3. 28 4月, 2017 8 次提交
  4. 25 4月, 2017 1 次提交
  5. 21 4月, 2017 1 次提交
  6. 09 4月, 2017 1 次提交
  7. 03 2月, 2017 1 次提交
  8. 28 1月, 2017 1 次提交
  9. 09 12月, 2016 1 次提交
  10. 21 11月, 2016 4 次提交
  11. 29 9月, 2016 1 次提交
    • H
      dm mpath: always return reservation conflict without failing over · 8ff232c1
      Hannes Reinecke 提交于
      If dm-mpath encounters an reservation conflict it should not fail the
      path (as communication with the target is not affected) but should
      rather retry on another path.  However, in doing so we might be inducing
      a ping-pong between paths, with no guarantee of any forward progress.
      And arguably a reservation conflict is an unexpected error, so we should
      be passing it upwards to allow the application to take appropriate
      steps.
      
      This change resolves a show-stopper problem seen with the pNFS SCSI
      layout because it is trivial to hit reservation conflict based failover
      loops without it.
      
      Doubts were raised about the implications of this change relative to
      products like IBM's SVC.  But there is little point withholding a fix
      for Linux because a proprietary product may or may not have some issues
      in its implementation of how it interfaces with Linux.  In the future,
      if there is glaring evidence that this change is certainly problematic
      we can revisit it.
      Signed-off-by: NHannes Reinecke <hare@suse.de>
      Acked-by: NChristoph Hellwig <hch@lst.de>
      Tested-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: Mike Snitzer <snitzer@redhat.com> # tweaked header
      8ff232c1
  12. 15 9月, 2016 4 次提交
  13. 08 8月, 2016 1 次提交
    • J
      block: rename bio bi_rw to bi_opf · 1eff9d32
      Jens Axboe 提交于
      Since commit 63a4cc24, bio->bi_rw contains flags in the lower
      portion and the op code in the higher portions. This means that
      old code that relies on manually setting bi_rw is most likely
      going to be broken. Instead of letting that brokeness linger,
      rename the member, to force old and out-of-tree code to break
      at compile time instead of at runtime.
      
      No intended functional changes in this commit.
      Signed-off-by: NJens Axboe <axboe@fb.com>
      1eff9d32
  14. 03 8月, 2016 1 次提交
  15. 11 6月, 2016 4 次提交
    • M
      dm mpath: add optional "queue_mode" feature · e83068a5
      Mike Snitzer 提交于
      Allow a user to specify an optional feature 'queue_mode <mode>' where
      <mode> may be "bio", "rq" or "mq" -- which corresponds to bio-based,
      request_fn rq-based, and blk-mq rq-based respectively.
      
      If the queue_mode feature isn't specified the default for the
      "multipath" target is still "rq" but if dm_mod.use_blk_mq is set to Y
      it'll default to mode "mq".
      
      This new queue_mode feature introduces the ability for each multipath
      device to have its own queue_mode (whereas before this feature all
      multipath devices effectively had to have the same queue_mode).
      
      This commit also goes a long way to eliminate the awkward (ab)use of
      DM_TYPE_*, the associated filter_md_type() and other relatively fragile
      and difficult to maintain code.
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      e83068a5
    • M
      bf661be1
    • M
      dm mpath: reinstate bio-based support · 76e33fe4
      Mike Snitzer 提交于
      Add "multipath-bio" target that offers a bio-based multipath target as
      an alternative to the request-based "multipath" target -- but in a
      following commit "multipath-bio" will immediately be replaced by a new
      "queue_mode" feature for the "multipath" target which will allow
      bio-based mode to be selected.
      
      When DM multipath was originally converted from bio-based to
      request-based the motivation for the change was better dynamic load
      balancing (by leveraging block core's request-based IO schedulers, for
      merging and sorting, _before_ DM multipath would make the decision on
      where to steer the IO -- based on path load and/or availability).
      
      More background is available in this "Request-based Device-mapper
      multipath and Dynamic load balancing" paper:
      https://www.kernel.org/doc/ols/2007/ols2007v2-pages-235-244.pdf
      
      But we've now come full circle where significantly faster storage
      devices no longer need IOs to be made larger to drive optimal IO
      performance.  And even if they do there have been changes to the block
      and filesystem layers that help ensure upper layers are constructing
      larger IOs.  In addition, SCSI's differentiated IO errors will propagate
      through to bio-based IO completion hooks -- so that eliminates another
      historic justiciation for request-based DM multipath.  Lastly, the block
      layer's immutable biovec changes have made bio cloning cheaper than it
      has ever been; whereas request cloning is still relatively expensive
      (both on a CPU usage and memory footprint level).
      
      As such, bio-based DM multipath offers the promise of a more efficient
      IO path for high IOPs devices that are, or will be, emerging.
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      76e33fe4
    • M
      dm: move request-based code out to dm-rq.[hc] · 4cc96131
      Mike Snitzer 提交于
      Add some seperation between bio-based and request-based DM core code.
      
      'struct mapped_device' and other DM core only structures and functions
      have been moved to dm-core.h and all relevant DM core .c files have been
      updated to include dm-core.h rather than dm.h
      
      DM targets should _never_ include dm-core.h!
      
      [block core merge conflict resolution from Stephen Rothwell]
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
      4cc96131
  16. 06 5月, 2016 4 次提交
  17. 11 3月, 2016 1 次提交
    • M
      dm mpath: cleanup reinstate_path() et al based on code review · ec31f3f7
      Mike Snitzer 提交于
      fail_path() will print a "Failing path ..." message but reinstate_path()
      doesn't print a "Reinstating path ...".  Add that message to
      reinstate_path() to add symmetry and aid system debugging.
      
      Remove reinstate_path()'s check for the path_selector providing
      .reinstate_path hook.  All path selectors provide this and any future
      ones must too.
      
      activate_path() calls pg_init_done() with SCSI_DH_DEV_OFFLINED but
      pg_init_done() doesn't expicitly handle it in its swicth statement.  Add
      SCSI_DH_DEV_OFFLINED to the default case.
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      ec31f3f7
  18. 23 2月, 2016 3 次提交