From ff3dd52d267165347d6f92a90016e692d074a00c Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Wed, 1 Oct 2014 14:02:10 +0300 Subject: IB/iser: Use beacon to indicate all completions were consumed Avoid post_send counting (atomic) in the IO path just to keep track of how many completions we need to consume. Use a beacon post to indicate that all prior posts completed. Signed-off-by: Sagi Grimberg Signed-off-by: Or Gerlitz Signed-off-by: Roland Dreier --- drivers/infiniband/ulp/iser/iscsi_iser.h | 5 +++-- drivers/infiniband/ulp/iser/iser_initiator.c | 8 ++----- drivers/infiniband/ulp/iser/iser_verbs.c | 32 ++++++++++++++++------------ 3 files changed, 23 insertions(+), 22 deletions(-) (limited to 'drivers/infiniband') diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h index 1617c5cce8b1..4fcb25604d80 100644 --- a/drivers/infiniband/ulp/iser/iscsi_iser.h +++ b/drivers/infiniband/ulp/iser/iscsi_iser.h @@ -150,6 +150,7 @@ #define ISER_RSV 0x04 #define ISER_FASTREG_LI_WRID 0xffffffffffffffffULL +#define ISER_BEACON_WRID 0xfffffffffffffffeULL struct iser_hdr { u8 flags; @@ -335,11 +336,11 @@ struct fast_reg_descriptor { * @cma_id: rdma_cm connection maneger handle * @qp: Connection Queue-pair * @post_recv_buf_count: post receive counter - * @post_send_buf_count: post send counter * @rx_wr: receive work request for batch posts * @device: reference to iser device * @comp: iser completion context * @pi_support: Indicate device T10-PI support + * @beacon: beacon send wr to signal all flush errors were drained * @flush_comp: completes when all connection completions consumed * @lock: protects fmr/fastreg pool * @union.fmr: @@ -355,11 +356,11 @@ struct ib_conn { struct rdma_cm_id *cma_id; struct ib_qp *qp; int post_recv_buf_count; - atomic_t post_send_buf_count; struct ib_recv_wr rx_wr[ISER_MIN_POSTED_RX]; struct iser_device *device; struct iser_comp *comp; bool pi_support; + struct ib_send_wr beacon; struct completion flush_comp; spinlock_t lock; union { diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c index 359c0b84f1ac..ffbdf922587a 100644 --- a/drivers/infiniband/ulp/iser/iser_initiator.c +++ b/drivers/infiniband/ulp/iser/iser_initiator.c @@ -350,12 +350,10 @@ static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req) return 0; /* - * Check that there is one posted recv buffer (for the last login - * response) and no posted send buffers left - they must have been - * consumed during previous login phases. + * Check that there is one posted recv buffer + * (for the last login response). */ WARN_ON(ib_conn->post_recv_buf_count != 1); - WARN_ON(atomic_read(&ib_conn->post_send_buf_count) != 0); if (session->discovery_sess) { iser_info("Discovery session, re-using login RX buffer\n"); @@ -634,8 +632,6 @@ void iser_snd_completion(struct iser_tx_desc *tx_desc, tx_desc = NULL; } - atomic_dec(&ib_conn->post_send_buf_count); - if (tx_desc && tx_desc->type == ISCSI_TX_CONTROL) { /* this arithmetic is legal by libiscsi dd_data allocation */ task = (void *) ((long)(void *)tx_desc - diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c index eedc27a0d3c3..805a9bdc9520 100644 --- a/drivers/infiniband/ulp/iser/iser_verbs.c +++ b/drivers/infiniband/ulp/iser/iser_verbs.c @@ -41,7 +41,8 @@ #define ISCSI_ISER_MAX_CONN 8 #define ISER_MAX_RX_LEN (ISER_QP_MAX_RECV_DTOS * ISCSI_ISER_MAX_CONN) #define ISER_MAX_TX_LEN (ISER_QP_MAX_REQ_DTOS * ISCSI_ISER_MAX_CONN) -#define ISER_MAX_CQ_LEN (ISER_MAX_RX_LEN + ISER_MAX_TX_LEN) +#define ISER_MAX_CQ_LEN (ISER_MAX_RX_LEN + ISER_MAX_TX_LEN + \ + ISCSI_ISER_MAX_CONN) static int iser_cq_poll_limit = 512; @@ -457,10 +458,10 @@ static int iser_create_ib_conn_res(struct ib_conn *ib_conn) init_attr.sq_sig_type = IB_SIGNAL_REQ_WR; init_attr.qp_type = IB_QPT_RC; if (ib_conn->pi_support) { - init_attr.cap.max_send_wr = ISER_QP_SIG_MAX_REQ_DTOS; + init_attr.cap.max_send_wr = ISER_QP_SIG_MAX_REQ_DTOS + 1; init_attr.create_flags |= IB_QP_CREATE_SIGNATURE_EN; } else { - init_attr.cap.max_send_wr = ISER_QP_MAX_REQ_DTOS; + init_attr.cap.max_send_wr = ISER_QP_MAX_REQ_DTOS + 1; } ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr); @@ -634,6 +635,7 @@ void iser_conn_release(struct iser_conn *iser_conn) int iser_conn_terminate(struct iser_conn *iser_conn) { struct ib_conn *ib_conn = &iser_conn->ib_conn; + struct ib_send_wr *bad_wr; int err = 0; /* terminate the iser conn only if the conn state is UP */ @@ -658,6 +660,11 @@ int iser_conn_terminate(struct iser_conn *iser_conn) iser_err("Failed to disconnect, conn: 0x%p err %d\n", iser_conn, err); + /* post an indication that all flush errors were consumed */ + err = ib_post_send(ib_conn->qp, &ib_conn->beacon, &bad_wr); + if (err) + iser_err("conn %p failed to post beacon", ib_conn); + wait_for_completion(&ib_conn->flush_comp); } @@ -867,7 +874,6 @@ void iser_conn_init(struct iser_conn *iser_conn) { iser_conn->state = ISER_CONN_INIT; iser_conn->ib_conn.post_recv_buf_count = 0; - atomic_set(&iser_conn->ib_conn.post_send_buf_count, 0); init_completion(&iser_conn->ib_conn.flush_comp); init_completion(&iser_conn->stop_completion); init_completion(&iser_conn->ib_completion); @@ -900,6 +906,9 @@ int iser_connect(struct iser_conn *iser_conn, iser_conn->state = ISER_CONN_PENDING; + ib_conn->beacon.wr_id = ISER_BEACON_WRID; + ib_conn->beacon.opcode = IB_WR_SEND; + ib_conn->cma_id = rdma_create_id(iser_cma_handler, (void *)iser_conn, RDMA_PS_TCP, IB_QPT_RC); @@ -1106,13 +1115,10 @@ int iser_post_send(struct ib_conn *ib_conn, struct iser_tx_desc *tx_desc) send_wr.opcode = IB_WR_SEND; send_wr.send_flags = IB_SEND_SIGNALED; - atomic_inc(&ib_conn->post_send_buf_count); - ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed); - if (ib_ret) { + if (ib_ret) iser_err("ib_post_send failed, ret:%d\n", ib_ret); - atomic_dec(&ib_conn->post_send_buf_count); - } + return ib_ret; } @@ -1164,7 +1170,6 @@ iser_handle_comp_error(struct ib_conn *ib_conn, if (is_iser_tx_desc(iser_conn, (void *)wc->wr_id)) { struct iser_tx_desc *desc = (struct iser_tx_desc *)wc->wr_id; - atomic_dec(&ib_conn->post_send_buf_count); if (desc->type == ISCSI_TX_DATAOUT) kmem_cache_free(ig.desc_cache, desc); } else { @@ -1196,7 +1201,6 @@ static void iser_handle_wc(struct ib_wc *wc) if (wc->opcode == IB_WC_SEND) { tx_desc = (struct iser_tx_desc *)wc->wr_id; iser_snd_completion(tx_desc, ib_conn); - atomic_dec(&ib_conn->post_send_buf_count); } else { iser_err("Unknown wc opcode %d\n", wc->opcode); } @@ -1207,12 +1211,12 @@ static void iser_handle_wc(struct ib_wc *wc) else iser_dbg("flush error: wr id %llx\n", wc->wr_id); - if (wc->wr_id != ISER_FASTREG_LI_WRID) + if (wc->wr_id != ISER_FASTREG_LI_WRID && + wc->wr_id != ISER_BEACON_WRID) iser_handle_comp_error(ib_conn, wc); /* complete in case all flush errors were consumed */ - if (ib_conn->post_recv_buf_count == 0 && - atomic_read(&ib_conn->post_send_buf_count) == 0) + if (wc->wr_id == ISER_BEACON_WRID) complete(&ib_conn->flush_comp); } } -- cgit v1.2.3