Hello, For bio based request queue, the queue usage refcnt is only grabbed during submission, which isn't consistent with request base queue. Queue freezing has been used widely, and turns out it is very useful to quiesce queue activity. So try to support to freeze bio based queue by ->q_usage_counter. Any comment are welcome! Ming Lei (2): percpu_ref: add percpu_ref_tryget_many_live block: support to freeze bio based request queue block/bio.c | 12 ++++++++++-- block/blk-core.c | 23 +++++++++++++++++------ drivers/nvme/host/core.c | 16 ++++++++++++++++ drivers/nvme/host/multipath.c | 6 ++++++ include/linux/blk-mq.h | 2 ++ include/linux/blk_types.h | 1 + include/linux/blkdev.h | 7 ++++++- include/linux/percpu-refcount.h | 30 ++++++++++++++++++++++++++---- 8 files changed, 84 insertions(+), 13 deletions(-) -- 2.29.2
