From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Wise Subject: [PATCH V6 5/9] RDMA/isert: Limit read depth based on the device max_sge_rd capability Date: Fri, 24 Jul 2015 11:18:43 -0500 Message-ID: <20150724161842.25617.8145.stgit@build2.ogc.int> References: <20150724161331.25617.8475.stgit@build2.ogc.int> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150724161331.25617.8475.stgit@build2.ogc.int> Sender: target-devel-owner@vger.kernel.org To: dledford@redhat.com Cc: infinipath@intel.com, sagig@mellanox.com, ogerlitz@mellanox.com, roid@mellanox.com, linux-rdma@vger.kernel.org, eli@mellanox.com, target-devel@vger.kernel.org, linux-nfs@vger.kernel.org, bfields@fieldses.org List-Id: linux-rdma@vger.kernel.org Use the device's max_sge_rd capability to compute the target's read sge depth. Save both the read and write max_sge values in the isert_conn struct, and use these when creating RDMA_WRITE/READ work requests. Signed-off-by: Steve Wise --- drivers/infiniband/ulp/isert/ib_isert.c | 24 ++++++++++++++++-------- drivers/infiniband/ulp/isert/ib_isert.h | 3 ++- 2 files changed, 18 insertions(+), 9 deletions(-) diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c index 7717009..6af3dd4 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -165,7 +165,9 @@ isert_create_qp(struct isert_conn *isert_conn, * outgoing control PDU responses. */ attr.cap.max_send_sge = max(2, device->dev_attr.max_sge - 2); - isert_conn->max_sge = attr.cap.max_send_sge; + isert_conn->max_write_sge = attr.cap.max_send_sge; + isert_conn->max_read_sge = min_t(u32, device->dev_attr.max_sge_rd, + attr.cap.max_send_sge); attr.cap.max_recv_sge = 1; attr.sq_sig_type = IB_SIGNAL_REQ_WR; @@ -2392,7 +2394,7 @@ isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn) static int isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd, struct ib_sge *ib_sge, struct ib_send_wr *send_wr, - u32 data_left, u32 offset) + u32 data_left, u32 offset, u32 max_sge) { struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd; struct scatterlist *sg_start, *tmp_sg; @@ -2403,7 +2405,7 @@ isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd, sg_off = offset / PAGE_SIZE; sg_start = &cmd->se_cmd.t_data_sg[sg_off]; - sg_nents = min(cmd->se_cmd.t_data_nents - sg_off, isert_conn->max_sge); + sg_nents = min(cmd->se_cmd.t_data_nents - sg_off, max_sge); page_off = offset % PAGE_SIZE; send_wr->sg_list = ib_sge; @@ -2449,8 +2451,9 @@ isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd, struct isert_data_buf *data = &wr->data; struct ib_send_wr *send_wr; struct ib_sge *ib_sge; - u32 offset, data_len, data_left, rdma_write_max, va_offset = 0; + u32 offset, data_len, data_left, rdma_max_len, va_offset = 0; int ret = 0, i, ib_sge_cnt; + u32 max_sge; isert_cmd->tx_desc.isert_cmd = isert_cmd; @@ -2472,7 +2475,12 @@ isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd, } wr->ib_sge = ib_sge; - wr->send_wr_num = DIV_ROUND_UP(data->nents, isert_conn->max_sge); + if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) + max_sge = isert_conn->max_write_sge; + else + max_sge = isert_conn->max_read_sge; + + wr->send_wr_num = DIV_ROUND_UP(data->nents, max_sge); wr->send_wr = kzalloc(sizeof(struct ib_send_wr) * wr->send_wr_num, GFP_KERNEL); if (!wr->send_wr) { @@ -2482,11 +2490,11 @@ isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd, } wr->isert_cmd = isert_cmd; - rdma_write_max = isert_conn->max_sge * PAGE_SIZE; + rdma_max_len = max_sge * PAGE_SIZE; for (i = 0; i < wr->send_wr_num; i++) { send_wr = &isert_cmd->rdma_wr.send_wr[i]; - data_len = min(data_left, rdma_write_max); + data_len = min(data_left, rdma_max_len); send_wr->send_flags = 0; if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) { @@ -2508,7 +2516,7 @@ isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd, } ib_sge_cnt = isert_build_rdma_wr(isert_conn, isert_cmd, ib_sge, - send_wr, data_len, offset); + send_wr, data_len, offset, max_sge); ib_sge += ib_sge_cnt; offset += data_len; diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h index 9ec23a7..29fde27 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.h +++ b/drivers/infiniband/ulp/isert/ib_isert.h @@ -152,7 +152,8 @@ struct isert_conn { u32 responder_resources; u32 initiator_depth; bool pi_support; - u32 max_sge; + u32 max_write_sge; + u32 max_read_sge; char *login_buf; char *login_req_buf; char *login_rsp_buf;