• Tejun Heo's avatar
    block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions · 050c8ea8
    Tejun Heo authored
    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: default avatarTejun Heo <tj@kernel.org>
    LKML-Reference: <4F16F3CA.90904@kernel.dk>
    Original-patch-by: default avatarJens Axboe <axboe@kernel.dk>
    Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
    050c8ea8
elevator.c 23.5 KB