Hi, blk-mq drivers often use managed IRQ, which affinity is setup automatically by genirq core. For managed IRQ, we need to make sure that there isn't in-flight requests when the managed IRQ is going to shutdown. This patch waits for inflight requests associated with one going-to-shutdown managed IRQ in blk-mq's CPU hotplug handler. One special case is that some SCSI devices have multiple private completion(reply) queue even though they only have one blk-mq hw queue, and the private completion queue is associated with one managed IRQ. Wait for inflight requests for these SCSI device too if last CPU of the completion queue is going to shutdown. SCSI device's internal commands aren't covered in this patchset, and they are much less important than requests from blk-mq/scsi core. V2: - cover private multiple completion(reply) queue - remove timeout during waitting, because some driver doesn't implemnt proper .timeout handler. Ming Lei (5): scsi: select reply queue from request's CPU blk-mq: introduce .complete_queue_affinity scsi: core: implement callback of .complete_queue_affinity scsi: implement .complete_queue_affinity blk-mq: Wait for for hctx inflight requests on CPU unplug block/blk-mq-tag.c | 2 +- block/blk-mq-tag.h | 5 ++ block/blk-mq.c | 94 +++++++++++++++++++-- drivers/scsi/hisi_sas/hisi_sas_main.c | 5 +- drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 11 +++ drivers/scsi/hpsa.c | 14 ++- drivers/scsi/megaraid/megaraid_sas_base.c | 10 +++ drivers/scsi/megaraid/megaraid_sas_fusion.c | 4 +- drivers/scsi/mpt3sas/mpt3sas_base.c | 16 ++-- drivers/scsi/mpt3sas/mpt3sas_scsih.c | 11 +++ drivers/scsi/scsi_lib.c | 14 +++ include/linux/blk-mq.h | 12 ++- include/scsi/scsi_cmnd.h | 11 +++ include/scsi/scsi_host.h | 10 +++ 14 files changed, 197 insertions(+), 22 deletions(-) -- 2.20.1