Hi, This patchset introduces flag of BLK_MQ_F_SCHED_USE_HW_TAG and allows to use hardware tag directly for IO scheduling if the queue's depth is big enough. In this way, we can avoid to allocate extra tags and request pool for IO schedule, and the schedule tag allocation/release can be saved in I/O submit path. Thanks, Ming Ming Lei (4): blk-mq: introduce BLK_MQ_F_SCHED_USE_HW_TAG blk-mq: introduce blk_mq_get_queue_depth() blk-mq: use hw tag for scheduling if hw tag space is big enough blk-mq: dump new introduced flag of BLK_MQ_F_SCHED_USE_HW_TAG block/blk-mq-debugfs.c | 1 + block/blk-mq-sched.c | 18 +++++++++++++- block/blk-mq-sched.h | 15 ++++++++++++ block/blk-mq.c | 65 ++++++++++++++++++++++++++++++++++++++++++++------ block/blk-mq.h | 1 + include/linux/blk-mq.h | 1 + 6 files changed, 93 insertions(+), 8 deletions(-) -- 2.9.3
