From fd1b6687091450b0ca3303c97f45ecd87401c3d7 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Fri, 25 Jan 2019 10:34:50 -0800 Subject: [PATCH] scsi: RDMA/srpt: Rework I/O context allocation Instead of maintaining a list of free I/O contexts, use an sbitmap data structure to track which I/O contexts are in use and which are free. This makes the ib_srpt driver more consistent with other LIO drivers. Cc: Doug Ledford Cc: Jason Gunthorpe Cc: Nicholas Bellinger Cc: Mike Christie Cc: Hannes Reinecke Cc: Christoph Hellwig Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- drivers/infiniband/ulp/srpt/ib_srpt.c | 47 +++++++++++---------------- drivers/infiniband/ulp/srpt/ib_srpt.h | 4 --- 2 files changed, 19 insertions(+), 32 deletions(-) diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c index 0dc2df925f76..d426e01905f9 100644 --- a/drivers/infiniband/ulp/srpt/ib_srpt.c +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c @@ -1217,22 +1217,15 @@ static int srpt_ch_qp_err(struct srpt_rdma_ch *ch) static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch) { struct srpt_send_ioctx *ioctx; - unsigned long flags; + int tag, cpu; BUG_ON(!ch); - ioctx = NULL; - spin_lock_irqsave(&ch->spinlock, flags); - if (!list_empty(&ch->free_list)) { - ioctx = list_first_entry(&ch->free_list, - struct srpt_send_ioctx, free_list); - list_del(&ioctx->free_list); - } - spin_unlock_irqrestore(&ch->spinlock, flags); - - if (!ioctx) - return ioctx; + tag = sbitmap_queue_get(&ch->sess->sess_tag_pool, &cpu); + if (tag < 0) + return NULL; + ioctx = ch->ioctx_ring[tag]; BUG_ON(ioctx->ch != ch); ioctx->state = SRPT_STATE_NEW; WARN_ON_ONCE(ioctx->recv_ioctx); @@ -1245,6 +1238,8 @@ static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch) */ memset(&ioctx->cmd, 0, sizeof(ioctx->cmd)); memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data)); + ioctx->cmd.map_tag = tag; + ioctx->cmd.map_cpu = cpu; return ioctx; } @@ -2148,7 +2143,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev, struct srpt_rdma_ch *ch = NULL; char i_port_id[36]; u32 it_iu_len; - int i, ret; + int i, tag_num, tag_size, ret; WARN_ON_ONCE(irqs_disabled()); @@ -2248,11 +2243,8 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev, goto free_rsp_cache; } - INIT_LIST_HEAD(&ch->free_list); - for (i = 0; i < ch->rq_size; i++) { + for (i = 0; i < ch->rq_size; i++) ch->ioctx_ring[i]->ch = ch; - list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list); - } if (!sdev->use_srq) { u16 imm_data_offset = req->req_flags & SRP_IMMED_REQUESTED ? be16_to_cpu(req->imm_data_offset) : 0; @@ -2306,18 +2298,20 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev, pr_debug("registering session %s\n", ch->sess_name); + tag_num = ch->rq_size; + tag_size = 1; /* ib_srpt does not use se_sess->sess_cmd_map */ if (sport->port_guid_tpg.se_tpg_wwn) - ch->sess = target_setup_session(&sport->port_guid_tpg, 0, 0, - TARGET_PROT_NORMAL, + ch->sess = target_setup_session(&sport->port_guid_tpg, tag_num, + tag_size, TARGET_PROT_NORMAL, ch->sess_name, ch, NULL); if (sport->port_gid_tpg.se_tpg_wwn && IS_ERR_OR_NULL(ch->sess)) - ch->sess = target_setup_session(&sport->port_gid_tpg, 0, 0, - TARGET_PROT_NORMAL, i_port_id, ch, - NULL); + ch->sess = target_setup_session(&sport->port_gid_tpg, tag_num, + tag_size, TARGET_PROT_NORMAL, i_port_id, + ch, NULL); /* Retry without leading "0x" */ if (sport->port_gid_tpg.se_tpg_wwn && IS_ERR_OR_NULL(ch->sess)) - ch->sess = target_setup_session(&sport->port_gid_tpg, 0, 0, - TARGET_PROT_NORMAL, + ch->sess = target_setup_session(&sport->port_gid_tpg, tag_num, + tag_size, TARGET_PROT_NORMAL, i_port_id + 2, ch, NULL); if (IS_ERR_OR_NULL(ch->sess)) { WARN_ON_ONCE(ch->sess == NULL); @@ -3279,7 +3273,6 @@ static void srpt_release_cmd(struct se_cmd *se_cmd) struct srpt_send_ioctx, cmd); struct srpt_rdma_ch *ch = ioctx->ch; struct srpt_recv_ioctx *recv_ioctx = ioctx->recv_ioctx; - unsigned long flags; WARN_ON_ONCE(ioctx->state != SRPT_STATE_DONE && !(ioctx->cmd.transport_state & CMD_T_ABORTED)); @@ -3295,9 +3288,7 @@ static void srpt_release_cmd(struct se_cmd *se_cmd) ioctx->n_rw_ctx = 0; } - spin_lock_irqsave(&ch->spinlock, flags); - list_add(&ioctx->free_list, &ch->free_list); - spin_unlock_irqrestore(&ch->spinlock, flags); + target_free_tag(se_cmd->se_sess, se_cmd); } /** diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.h b/drivers/infiniband/ulp/srpt/ib_srpt.h index 39b3e50baf3d..ee9f20e9177a 100644 --- a/drivers/infiniband/ulp/srpt/ib_srpt.h +++ b/drivers/infiniband/ulp/srpt/ib_srpt.h @@ -207,7 +207,6 @@ struct srpt_rw_ctx { * @rw_ctxs: RDMA read/write contexts. * @imm_sg: Scatterlist for immediate data. * @rdma_cqe: RDMA completion queue element. - * @free_list: Node in srpt_rdma_ch.free_list. * @state: I/O context state. * @cmd: Target core command data structure. * @sense_data: SCSI sense data. @@ -227,7 +226,6 @@ struct srpt_send_ioctx { struct scatterlist imm_sg; struct ib_cqe rdma_cqe; - struct list_head free_list; enum srpt_command_state state; struct se_cmd cmd; u8 n_rdma; @@ -277,7 +275,6 @@ enum rdma_ch_state { * @req_lim_delta: Number of credits not yet sent back to the initiator. * @imm_data_offset: Offset from start of SRP_CMD for immediate data. * @spinlock: Protects free_list and state. - * @free_list: Head of list with free send I/O contexts. * @state: channel state. See also enum rdma_ch_state. * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel. * @processing_wait_list: Whether or not cmd_wait_list is being processed. @@ -318,7 +315,6 @@ struct srpt_rdma_ch { atomic_t req_lim_delta; u16 imm_data_offset; spinlock_t spinlock; - struct list_head free_list; enum rdma_ch_state state; struct kmem_cache *rsp_buf_cache; struct srpt_send_ioctx **ioctx_ring; -- 2.30.2