lwn.git/drivers/scsi/scsi_lib.c, branch v6.8-rc6

scsi: core: Move scsi_host_busy() out of host lock if it is for per-command

2024-02-05T21:15:20+00:00

Commit 4373534a9850 ("scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler") intended to fix a hard lockup issue triggered by EH. The core idea was to move scsi_host_busy() out of the host lock when processing individual commands for EH. However, a suggested style change inadvertently caused scsi_host_busy() to remain under the host lock. Fix this by calling scsi_host_busy() outside the lock. Fixes: 4373534a9850 ("scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler") Cc: Sathya Prakash Veerichetty Cc: Bart Van Assche Cc: Ewan D. Milne Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20240203024521.2006455-1-ming.lei@redhat.com Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler

2024-01-24T02:21:51+00:00

Inside scsi_eh_wakeup(), scsi_host_busy() is called & checked with host lock every time for deciding if error handler kthread needs to be waken up. This can be too heavy in case of recovery, such as: - N hardware queues - queue depth is M for each hardware queue - each scsi_host_busy() iterates over (N * M) tag/requests If recovery is triggered in case that all requests are in-flight, each scsi_eh_wakeup() is strictly serialized, when scsi_eh_wakeup() is called for the last in-flight request, scsi_host_busy() has been run for (N * M - 1) times, and request has been iterated for (N*M - 1) * (N * M) times. If both N and M are big enough, hard lockup can be triggered on acquiring host lock, and it is observed on mpi3mr(128 hw queues, queue depth 8169). Fix the issue by calling scsi_host_busy() outside the host lock. We don't need the host lock for getting busy count because host the lock never covers that. [mkp: Drop unnecessary 'busy' variables pointed out by Bart] Cc: Ewan Milne Fixes: 6eb045e092ef ("scsi: core: avoid host-wide host_busy counter for scsi_mq") Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20240112070000.4161982-1-ming.lei@redhat.com Reviewed-by: Ewan D. Milne Reviewed-by: Sathya Prakash Veerichetty Tested-by: Sathya Prakash Veerichetty Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: core: Clean up scsi_dev_queue_ready()

2023-10-25T02:31:04+00:00

This is just a cleanup for scsi_dev_queue_ready() to avoid a redundant goto and if statement. No functional change. Signed-off-by: Wenchao Hao Link: https://lore.kernel.org/r/20231018113746.1940197-2-haowenchao2@huawei.com Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: core: Handle depopulation and restoration in progress

2023-10-17T01:02:23+00:00

The default handling of the NOT READY sense key is to wait for the device to become ready. The "wait" is assumed to be relatively short. However there is a sub-class of NOT READY that have the "... in progress" phrase in their additional sense code and these can take much longer. Following on from commit 505aa4b6a883 ("scsi: sd: Defer spinning up drive while SANITIZE is in progress") we now have element depopulation and restoration that can take a long time. For example, over 24 hours for a 20 TB, 7200 rpm hard disk to depopulate 1 of its 20 elements. Add handling of ASC/ASCQ: 0x4,0x24 (depopulation in progress) and ASC/ASCQ: 0x4,0x25 (depopulation restoration in progress) to sd.c . The scsi_lib.c has incomplete handling of these two messages, so complete it. Signed-off-by: Douglas Gilbert Link: https://lore.kernel.org/r/20231015050650.131145-1-dgilbert@interlog.com Signed-off-by: Martin K. Petersen

scsi: Fix sshdr use in scsi_test_unit_ready

2023-10-13T20:36:20+00:00

If scsi_execute_cmd returns < 0, it doesn't initialize the sshdr, so we shouldn't access the sshdr. If it returns 0, then the cmd executed successfully, so there is no need to check the sshdr. This has us access the sshdr when we get a return value > 0. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20231004210013.5601-10-michael.christie@oracle.com Reviewed-by: Christoph Hellwig Reviewed-by: John Garry Reviewed-by: Martin Wilck Signed-off-by: Martin K. Petersen

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2023-09-09T19:01:33+00:00

Pull more SCSI updates from James Bottomley: "Mostly small stragglers that missed the initial merge. Driver updates are qla2xxx and smartpqi (mp3sas has a high diffstat due to the volatile qualifier removal, fnic due to unused function removal and sd.c has a lot of code shuffling to remove forward declarations)" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (38 commits) scsi: ufs: core: No need to update UPIU.header.flags and lun in advanced RPMB handler scsi: ufs: core: Add advanced RPMB support where UFSHCI 4.0 does not support EHS length in UTRD scsi: mpt3sas: Remove volatile qualifier scsi: mpt3sas: Perform additional retries if doorbell read returns 0 scsi: libsas: Simplify sas_queue_reset() and remove unused code scsi: ufs: Fix the build for the old ARM OABI scsi: qla2xxx: Fix unused variable warning in qla2xxx_process_purls_pkt() scsi: fnic: Remove unused functions fnic_scsi_host_start/end_tag() scsi: qla2xxx: Fix spelling mistake "tranport" -> "transport" scsi: fnic: Replace sgreset tag with max_tag_id scsi: qla2xxx: Remove unused variables in qla24xx_build_scsi_type_6_iocbs() scsi: qla2xxx: Fix nvme_fc_rcv_ls_req() undefined error scsi: smartpqi: Change driver version to 2.1.24-046 scsi: smartpqi: Enhance error messages scsi: smartpqi: Enhance controller offline notification scsi: smartpqi: Enhance shutdown notification scsi: smartpqi: Simplify lun_number assignment scsi: smartpqi: Rename pciinfo to pci_info scsi: smartpqi: Rename MACRO to clarify purpose scsi: smartpqi: Add abort handler ...

scsi: core: Improve type safety of scsi_rescan_device()

2023-08-25T02:11:29+00:00

Most callers of scsi_rescan_device() have the scsi_device pointer readily available. Pass a struct scsi_device pointer to scsi_rescan_device() instead of a struct device pointer. This change prevents that a pointer to another struct device would be passed accidentally to scsi_rescan_device(). Remove the scsi_rescan_device() declaration from the scsi_priv.h header file since it duplicates the declaration in . Reviewed-by: Hannes Reinecke Reviewed-by: Damien Le Moal Reviewed-by: John Garry Cc: Mike Christie Cc: Ming Lei Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230822153043.4046244-1-bvanassche@acm.org Signed-off-by: Martin K. Petersen

block: Improve performance for BLK_MQ_F_BLOCKING drivers

2023-07-25T02:13:12+00:00

blk_mq_run_queue() runs the queue asynchronously if BLK_MQ_F_BLOCKING has been set. This is suboptimal since running the queue asynchronously is slower than running the queue synchronously. This patch modifies blk_mq_run_queue() as follows if BLK_MQ_F_BLOCKING has been set: - Run the queue synchronously if it is allowed to sleep. - Run the queue asynchronously if it is not allowed to sleep. Additionally, blk_mq_run_hw_queue(hctx, false) calls are modified into blk_mq_run_hw_queue(hctx, hctx->flags & BLK_MQ_F_BLOCKING) if the caller may be invoked from atomic context. The following caller chains have been reviewed: blk_mq_run_hw_queue(hctx, false) blk_mq_get_tag() /* may sleep, hence the functions it calls may also sleep */ blk_execute_rq() /* may sleep */ blk_mq_run_hw_queues(q, async=false) blk_freeze_queue_start() /* may sleep */ blk_mq_requeue_work() /* may sleep */ scsi_kick_queue() scsi_requeue_run_queue() /* may sleep */ scsi_run_host_queues() scsi_ioctl_reset() /* may sleep */ blk_mq_insert_requests(hctx, ctx, list, run_queue_async=false) blk_mq_dispatch_plug_list(plug, from_sched=false) blk_mq_flush_plug_list(plug, from_schedule=false) __blk_flush_plug(plug, from_schedule=false) blk_add_rq_to_plug() blk_mq_submit_bio() /* may sleep if REQ_NOWAIT has not been set */ blk_mq_plug_issue_direct() blk_mq_flush_plug_list() /* see above */ blk_mq_dispatch_plug_list(plug, from_sched=false) blk_mq_flush_plug_list() /* see above */ blk_mq_try_issue_directly() blk_mq_submit_bio() /* may sleep if REQ_NOWAIT has not been set */ blk_mq_try_issue_list_directly(hctx, list) blk_mq_insert_requests() /* see above */ Cc: Christoph Hellwig Cc: Ming Lei Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230721172731.955724-4-bvanassche@acm.org Signed-off-by: Jens Axboe

scsi: Remove a blk_mq_run_hw_queues() call

2023-07-25T02:13:12+00:00

blk_mq_kick_requeue_list() calls blk_mq_run_hw_queues() asynchronously. Leave out the direct blk_mq_run_hw_queues() call. This patch causes scsi_run_queue() to call blk_mq_run_hw_queues() asynchronously instead of synchronously. Since scsi_run_queue() is not called from the hot I/O submission path, this patch does not affect the hot path. This patch prepares for allowing blk_mq_run_hw_queue() to sleep if BLK_MQ_F_BLOCKING has been set. scsi_run_queue() may be called from atomic context and must not sleep. Hence the removal of the blk_mq_run_hw_queues(q, false) call. See also scsi_unblock_requests(). Cc: "Martin K. Petersen" Signed-off-by: Bart Van Assche Reviewed-by: "Martin K. Petersen" Link: https://lore.kernel.org/r/20230721172731.955724-3-bvanassche@acm.org Signed-off-by: Jens Axboe

scsi: Inline scsi_kick_queue()

2023-07-25T02:13:12+00:00

Inline scsi_kick_queue() to prepare for modifying the second argument passed to blk_mq_run_hw_queues(). Reviewed-by: Christoph Hellwig Cc: "Martin K. Petersen" Signed-off-by: Bart Van Assche Reviewed-by: "Martin K. Petersen" Link: https://lore.kernel.org/r/20230721172731.955724-2-bvanassche@acm.org Signed-off-by: Jens Axboe