1. 11 11月, 2017 34 次提交
  2. 08 11月, 2017 2 次提交
  3. 07 11月, 2017 2 次提交
  4. 05 11月, 2017 2 次提交
    • M
      blk-mq: don't allocate driver tag upfront for flush rq · 923218f6
      Ming Lei 提交于
      The idea behind it is simple:
      
      1) for none scheduler, driver tag has to be borrowed for flush rq,
         otherwise we may run out of tag, and that causes an IO hang. And
         get/put driver tag is actually noop for none, so reordering tags
         isn't necessary at all.
      
      2) for a real I/O scheduler, we need not allocate a driver tag upfront
         for flush rq. It works just fine to follow the same approach as
         normal requests: allocate driver tag for each rq just before calling
         ->queue_rq().
      
      One driver visible change is that the driver tag isn't shared in the
      flush request sequence. That won't be a problem, since we always do that
      in legacy path.
      
      Then flush rq need not be treated specially wrt. get/put driver tag.
      This cleans up the code - for instance, reorder_tags_to_front() can be
      removed, and we needn't worry about request ordering in dispatch list
      for avoiding I/O deadlock.
      
      Also we have to put the driver tag before requeueing.
      Signed-off-by: NMing Lei <ming.lei@redhat.com>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      923218f6
    • M
      blk-mq: move blk_mq_put_driver_tag*() into blk-mq.h · 244c65a3
      Ming Lei 提交于
      We need this helper to put the driver tag for flush rq, since we will
      not share tag in the flush request sequence in the following patch
      in case that I/O scheduler is applied.
      Signed-off-by: NMing Lei <ming.lei@redhat.com>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      244c65a3