From fbd36818eea88462be4176c9fb73bb7728971ff5 Mon Sep 17 00:00:00 2001 From: Sergey Gorenko Date: Mon, 5 Mar 2018 20:15:56 +0200 Subject: [PATCH] IB/srp: Use the IB_DEVICE_SG_GAPS_REG HCA feature if supported If a HCA supports the SG_GAPS_REG feature then fewer memory regions are required per command. This patch reduces the number of memory regions that is allocated per SRP session. Signed-off-by: Sergey Gorenko Reviewed-by: Max Gurtovoy Tested-by: Laurence Oberman Signed-off-by: Leon Romanovsky Acked-by: Bart Van Assche Signed-off-by: Jason Gunthorpe --- drivers/infiniband/ulp/srp/ib_srp.c | 56 ++++++++++++++++++----------- 1 file changed, 36 insertions(+), 20 deletions(-) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index d61f48a86508..9a5ea6251450 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -431,6 +431,7 @@ static struct srp_fr_pool *srp_create_fr_pool(struct ib_device *device, struct srp_fr_desc *d; struct ib_mr *mr; int i, ret = -EINVAL; + enum ib_mr_type mr_type; if (pool_size <= 0) goto err; @@ -444,9 +445,13 @@ static struct srp_fr_pool *srp_create_fr_pool(struct ib_device *device, spin_lock_init(&pool->lock); INIT_LIST_HEAD(&pool->free_list); + if (device->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG) + mr_type = IB_MR_TYPE_SG_GAPS; + else + mr_type = IB_MR_TYPE_MEM_REG; + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { - mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, - max_page_list_len); + mr = ib_alloc_mr(pd, mr_type, max_page_list_len); if (IS_ERR(mr)) { ret = PTR_ERR(mr); if (ret == -ENOMEM) @@ -2996,8 +3001,9 @@ static int srp_slave_alloc(struct scsi_device *sdev) struct Scsi_Host *shost = sdev->host; struct srp_target_port *target = host_to_target(shost); struct srp_device *srp_dev = target->srp_host->srp_dev; + struct ib_device *ibdev = srp_dev->dev; - if (true) + if (!(ibdev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)) blk_queue_virt_boundary(sdev->request_queue, ~srp_dev->mr_page_mask); @@ -3775,26 +3781,36 @@ static ssize_t srp_create_target(struct device *dev, } if (srp_dev->use_fast_reg || srp_dev->use_fmr) { - /* - * FR and FMR can only map one HCA page per entry. If the - * start address is not aligned on a HCA page boundary two - * entries will be used for the head and the tail although - * these two entries combined contain at most one HCA page of - * data. Hence the "+ 1" in the calculation below. - * - * The indirect data buffer descriptor is contiguous so the - * memory for that buffer will only be registered if - * register_always is true. Hence add one to mr_per_cmd if - * register_always has been set. - */ + bool gaps_reg = (ibdev->attrs.device_cap_flags & + IB_DEVICE_SG_GAPS_REG); + max_sectors_per_mr = srp_dev->max_pages_per_mr << (ilog2(srp_dev->mr_page_size) - 9); - mr_per_cmd = register_always + - (target->scsi_host->max_sectors + 1 + - max_sectors_per_mr - 1) / max_sectors_per_mr; + if (!gaps_reg) { + /* + * FR and FMR can only map one HCA page per entry. If + * the start address is not aligned on a HCA page + * boundary two entries will be used for the head and + * the tail although these two entries combined + * contain at most one HCA page of data. Hence the "+ + * 1" in the calculation below. + * + * The indirect data buffer descriptor is contiguous + * so the memory for that buffer will only be + * registered if register_always is true. Hence add + * one to mr_per_cmd if register_always has been set. + */ + mr_per_cmd = register_always + + (target->scsi_host->max_sectors + 1 + + max_sectors_per_mr - 1) / max_sectors_per_mr; + } else { + mr_per_cmd = register_always + + (target->sg_tablesize + + srp_dev->max_pages_per_mr - 1) / + srp_dev->max_pages_per_mr; + } pr_debug("max_sectors = %u; max_pages_per_mr = %u; mr_page_size = %u; max_sectors_per_mr = %u; mr_per_cmd = %u\n", - target->scsi_host->max_sectors, - srp_dev->max_pages_per_mr, srp_dev->mr_page_size, + target->scsi_host->max_sectors, srp_dev->max_pages_per_mr, srp_dev->mr_page_size, max_sectors_per_mr, mr_per_cmd); } -- 2.30.2