1. 08 2月, 2012 1 次提交
    • T
      block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions · 050c8ea8
      Tejun Heo 提交于
      blk_rq_merge_ok() is the elevator-neutral part of merge eligibility
      test.  blk_try_merge() determines merge direction and expects the
      caller to have tested elv_rq_merge_ok() previously.
      
      elv_rq_merge_ok() now wraps blk_rq_merge_ok() and then calls
      elv_iosched_allow_merge().  elv_try_merge() is removed and the two
      callers are updated to call elv_rq_merge_ok() explicitly followed by
      blk_try_merge().  While at it, make rq_merge_ok() functions return
      bool.
      
      This is to prepare for plug merge update and doesn't introduce any
      behavior change.
      
      This is based on Jens' patch to skip elevator_allow_merge_fn() from
      plug merge.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      LKML-Reference: <4F16F3CA.90904@kernel.dk>
      Original-patch-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      050c8ea8
  2. 07 2月, 2012 1 次提交
    • T
      block: strip out locking optimization in put_io_context() · 11a3122f
      Tejun Heo 提交于
      put_io_context() performed a complex trylock dancing to avoid
      deferring ioc release to workqueue.  It was also broken on UP because
      trylock was always assumed to succeed which resulted in unbalanced
      preemption count.
      
      While there are ways to fix the UP breakage, even the most
      pathological microbench (forced ioc allocation and tight fork/exit
      loop) fails to show any appreciable performance benefit of the
      optimization.  Strip it out.  If there turns out to be workloads which
      are affected by this change, simpler optimization from the discussion
      thread can be applied later.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      LKML-Reference: <1328514611.21268.66.camel@sli10-conroe>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      11a3122f
  3. 18 1月, 2012 20 次提交
  4. 17 1月, 2012 18 次提交