kernel/linux.git/block/blk-mq-debugfs.c, branch v6.6.141

blk-mq-debugfs: add missing debugfs_mutex in blk_mq_debugfs_register_hctxs()

2026-03-04T12:20:35+00:00

[ Upstream commit 9d20fd6ce1ba9733cd5ac96fcab32faa9fc404dd ] In blk_mq_update_nr_hw_queues(), debugfs_mutex is not held while creating debugfs entries for hctxs. Hence add debugfs_mutex there, it's safe because queue is not frozen. Signed-off-by: Yu Kuai Reviewed-by: Nilay Shroff Reviewed-by: Ming Lei Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

blk-mq: fix potential io hang by wrong 'wake_batch'

2023-06-12T15:55:53+00:00

In __blk_mq_tag_busy/idle(), updating 'active_queues' and calculating 'wake_batch' is not atomic: t1: t2: _blk_mq_tag_busy blk_mq_tag_busy inc active_queues // assume 1->2 inc active_queues // 2 -> 3 blk_mq_update_wake_batch // calculate based on 3 blk_mq_update_wake_batch /* calculate based on 2, while active_queues is actually 3. */ Fix this problem by protecting them wih 'tags->lock', this is not a hot path, so performance should not be concerned. And now that all writers are inside the lock, switch 'actives_queues' from atomic to unsigned int. Fixes: 180dccb0dba4 ("blk-mq: fix tag_get wait task can't be awakened") Signed-off-by: Yu Kuai Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20230610023043.2559121-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe

blk-mq: don't use the requeue list to queue flush commands

2023-05-20T01:52:42+00:00

Currently both requeues of commands that were already sent to the driver and flush commands submitted from the flush state machine share the same requeue_list struct request_queue, despite requeues doing head insertions and flushes not. Switch to using two separate lists instead. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20230519044050.107790-8-hch@lst.de Signed-off-by: Jens Axboe

blk-mq: make sure elevator callbacks aren't called for passthrough request

2023-05-19T01:42:54+00:00

In case of q->elevator, passthrough request can still be marked as RQF_ELV, so some elevator callbacks will be called for them. Fix this by splitting RQF_SCHED_TAGS, which is set for all requests that are issued on a queue that uses an I/O scheduler, and RQF_USE_SCHED for non-flush, non-passthrough requests on such a queue. Roughly based on two different patches from Ming Lei . Signed-off-by: Christoph Hellwig Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20230518053101.760632-4-hch@lst.de Signed-off-by: Jens Axboe

blk-mq: remove RQF_ELVPRIV

2023-05-19T01:41:20+00:00

RQF_ELVPRIV is set for all non-flush requests that have RQF_ELV set. Expand this condition in the two users of the flag and remove it. Signed-off-by: Christoph Hellwig Reviewed-by: Ming Lei Reviewed-by: Bart Van Assche Link: https://lore.kernel.org/r/20230518053101.760632-3-hch@lst.de Signed-off-by: Jens Axboe

block: Decode all flag names in the debugfs output

2023-05-19T01:34:31+00:00

See also: * Commit 4d337cebcb1c ("blk-mq: avoid to touch q->elevator without any protection"). * Commit 414dd48e882c ("blk-mq: add tagset quiesce interface"). Cc: Christoph Hellwig Cc: Damien Le Moal Cc: Ming Lei Cc: Chaitanya Kulkarni Signed-off-by: Bart Van Assche Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20230518222708.1190867-1-bvanassche@acm.org Signed-off-by: Jens Axboe

blk-mq: include in block/blk-mq.h

2023-04-13T12:52:29+00:00

block/blk-mq.h needs various definitions from , include it there instead of relying on the source files to include both. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20230413064057.707578-4-hch@lst.de Signed-off-by: Jens Axboe

blk-mq: remove blk-mq-tag.h

2023-04-13T12:52:29+00:00

blk-mq-tag.h is always included by blk-mq.h, and causes recursive inclusion hell with further changes. Just merge it into blk-mq.h instead. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20230413064057.707578-3-hch@lst.de Signed-off-by: Jens Axboe

blk-mq: remove hybrid polling

2023-03-20T21:30:03+00:00

io_uring provides the only way user space can poll completions, and that always sets BLK_POLL_NOSLEEP. This effectively makes hybrid polling dead code, so remove it and everything supporting it. Hybrid polling was effectively killed off with 9650b453a3d4b1, "block: ignore RWF_HIPRI hint for sync dio", but still potentially reachable through io_uring until d729cf9acb93119, "io_uring: don't sleep when polling for I/O", but hybrid polling probably should not have been reachable through that async interface from the beginning. Fixes: 9650b453a3d4 ("block: ignore RWF_HIPRI hint for sync dio") Fixes: d729cf9acb93 ("io_uring: don't sleep when polling for I/O") Signed-off-by: Keith Busch Link: https://lore.kernel.org/r/20230320194926.3353144-1-kbusch@meta.com Signed-off-by: Jens Axboe

blk-rq-qos: store a gendisk instead of request_queue in struct rq_qos

2023-02-03T15:20:05+00:00

This is what about half of the users already want, and it's only going to grow more. Signed-off-by: Christoph Hellwig Reviewed-by: Andreas Herrmann Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20230203150400.3199230-16-hch@lst.de Signed-off-by: Jens Axboe