Add support for host_tagset. Also move the reserved command slots to the end of the pool to eliminate an addition operation for every SCSI request. This patch was originally authored by Hannes Reinecke here: Link: https://lore.kernel.org/linux-block/20191126131009.71726-8-hare@xxxxxxx/ But we NAKed this patch because we wanted to fully test multipath failover operations. Suggested-by: Hannes Reinecke <hare@xxxxxxx> Reviewed-by: Scott Benesh <scott.benesh@xxxxxxxxxxxxx> Reviewed-by: Scott Teel <scott.teel@xxxxxxxxxxxxx> Reviewed-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@xxxxxxxxxxxxx> Reviewed-by: Mike McGowen <Mike.McGowen@xxxxxxxxxxxxx> Reviewed-by: Kevin Barnett <kevin.barnett@xxxxxxxxxxxxx> Signed-off-by: Don Brace <don.brace@xxxxxxxxxxxxx> --- drivers/scsi/smartpqi/smartpqi.h | 3 - drivers/scsi/smartpqi/smartpqi_init.c | 68 +++++++++++++++++++++------------ 2 files changed, 43 insertions(+), 28 deletions(-) diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h index e550b12e525a..8cdf4d2476dd 100644 --- a/drivers/scsi/smartpqi/smartpqi.h +++ b/drivers/scsi/smartpqi/smartpqi.h @@ -1307,7 +1307,6 @@ struct pqi_ctrl_info { dma_addr_t error_buffer_dma_handle; size_t sg_chain_buffer_length; unsigned int num_queue_groups; - u16 max_hw_queue_index; u16 num_elements_per_iq; u16 num_elements_per_oq; u16 max_inbound_iu_length_per_firmware; @@ -1369,8 +1368,6 @@ struct pqi_ctrl_info { u64 sas_address; struct pqi_io_request *io_request_pool; - u16 next_io_request_slot; - struct pqi_event events[PQI_NUM_SUPPORTED_EVENTS]; struct work_struct event_work; diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c index b971fbe3b3a1..651dca535b3b 100644 --- a/drivers/scsi/smartpqi/smartpqi_init.c +++ b/drivers/scsi/smartpqi/smartpqi_init.c @@ -678,23 +678,36 @@ static inline void pqi_reinit_io_request(struct pqi_io_request *io_request) io_request->raid_bypass = false; } -static struct pqi_io_request *pqi_alloc_io_request( - struct pqi_ctrl_info *ctrl_info) +static inline struct pqi_io_request *pqi_alloc_io_request(struct pqi_ctrl_info *ctrl_info, struct scsi_cmnd *scmd) { struct pqi_io_request *io_request; - u16 i = ctrl_info->next_io_request_slot; /* benignly racy */ + u16 i; - while (1) { + if (scmd) { /* SML I/O request */ + u32 blk_tag = blk_mq_unique_tag(scsi_cmd_to_rq(scmd)); + + i = blk_mq_unique_tag_to_tag(blk_tag); io_request = &ctrl_info->io_request_pool[i]; - if (atomic_inc_return(&io_request->refcount) == 1) - break; - atomic_dec(&io_request->refcount); - i = (i + 1) % ctrl_info->max_io_slots; + if (atomic_inc_return(&io_request->refcount) > 1) { + atomic_dec(&io_request->refcount); + return NULL; + } + } else { /* IOCTL or driver internal request */ + /* + * benignly racy - may have to wait for an open slot. + * command slot range is scsi_ml_can_queue - + * [scsi_ml_can_queue + (PQI_RESERVED_IO_SLOTS - 1)] + */ + i = 0; + while (1) { + io_request = &ctrl_info->io_request_pool[ctrl_info->scsi_ml_can_queue + i]; + if (atomic_inc_return(&io_request->refcount) == 1) + break; + atomic_dec(&io_request->refcount); + i = (i + 1) % PQI_RESERVED_IO_SLOTS; + } } - /* benignly racy */ - ctrl_info->next_io_request_slot = (i + 1) % ctrl_info->max_io_slots; - pqi_reinit_io_request(io_request); return io_request; @@ -4586,7 +4599,7 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info, goto out; } - io_request = pqi_alloc_io_request(ctrl_info); + io_request = pqi_alloc_io_request(ctrl_info, NULL); put_unaligned_le16(io_request->index, &(((struct pqi_raid_path_request *)request)->request_id)); @@ -5233,7 +5246,6 @@ static void pqi_calculate_queue_resources(struct pqi_ctrl_info *ctrl_info) } ctrl_info->num_queue_groups = num_queue_groups; - ctrl_info->max_hw_queue_index = num_queue_groups - 1; /* * Make sure that the max. inbound IU length is an even multiple @@ -5567,7 +5579,9 @@ static inline int pqi_raid_submit_scsi_cmd(struct pqi_ctrl_info *ctrl_info, { struct pqi_io_request *io_request; - io_request = pqi_alloc_io_request(ctrl_info); + io_request = pqi_alloc_io_request(ctrl_info, scmd); + if (!io_request) + return SCSI_MLQUEUE_HOST_BUSY; return pqi_raid_submit_scsi_cmd_with_io_request(ctrl_info, io_request, device, scmd, queue_group); @@ -5671,7 +5685,9 @@ static int pqi_aio_submit_io(struct pqi_ctrl_info *ctrl_info, struct pqi_scsi_dev *device; device = scmd->device->hostdata; - io_request = pqi_alloc_io_request(ctrl_info); + io_request = pqi_alloc_io_request(ctrl_info, scmd); + if (!io_request) + return SCSI_MLQUEUE_HOST_BUSY; io_request->io_complete_callback = pqi_aio_io_complete; io_request->scmd = scmd; io_request->raid_bypass = raid_bypass; @@ -5743,7 +5759,10 @@ static int pqi_aio_submit_r1_write_io(struct pqi_ctrl_info *ctrl_info, struct pqi_io_request *io_request; struct pqi_aio_r1_path_request *r1_request; - io_request = pqi_alloc_io_request(ctrl_info); + io_request = pqi_alloc_io_request(ctrl_info, scmd); + if (!io_request) + return SCSI_MLQUEUE_HOST_BUSY; + io_request->io_complete_callback = pqi_aio_io_complete; io_request->scmd = scmd; io_request->raid_bypass = true; @@ -5801,7 +5820,9 @@ static int pqi_aio_submit_r56_write_io(struct pqi_ctrl_info *ctrl_info, struct pqi_io_request *io_request; struct pqi_aio_r56_path_request *r56_request; - io_request = pqi_alloc_io_request(ctrl_info); + io_request = pqi_alloc_io_request(ctrl_info, scmd); + if (!io_request) + return SCSI_MLQUEUE_HOST_BUSY; io_request->io_complete_callback = pqi_aio_io_complete; io_request->scmd = scmd; io_request->raid_bypass = true; @@ -5860,13 +5881,10 @@ static int pqi_aio_submit_r56_write_io(struct pqi_ctrl_info *ctrl_info, static inline u16 pqi_get_hw_queue(struct pqi_ctrl_info *ctrl_info, struct scsi_cmnd *scmd) { - u16 hw_queue; - - hw_queue = blk_mq_unique_tag_to_hwq(blk_mq_unique_tag(scsi_cmd_to_rq(scmd))); - if (hw_queue > ctrl_info->max_hw_queue_index) - hw_queue = 0; - - return hw_queue; + /* + * We are setting host_tagset = 1 during init. + */ + return blk_mq_unique_tag_to_hwq(blk_mq_unique_tag(scsi_cmd_to_rq(scmd))); } static inline bool pqi_is_bypass_eligible_request(struct scsi_cmnd *scmd) @@ -6268,7 +6286,7 @@ static int pqi_lun_reset(struct pqi_ctrl_info *ctrl_info, struct scsi_cmnd *scmd struct pqi_scsi_dev *device; device = scmd->device->hostdata; - io_request = pqi_alloc_io_request(ctrl_info); + io_request = pqi_alloc_io_request(ctrl_info, NULL); io_request->io_complete_callback = pqi_lun_reset_complete; io_request->context = &wait;
