diff options
Diffstat (limited to 'drivers/infiniband/hw/hfi1/tid_rdma.c')
| -rw-r--r-- | drivers/infiniband/hw/hfi1/tid_rdma.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/tid_rdma.c b/drivers/infiniband/hw/hfi1/tid_rdma.c index 506b5a59ded5..56c8c10b5a85 100644 --- a/drivers/infiniband/hw/hfi1/tid_rdma.c +++ b/drivers/infiniband/hw/hfi1/tid_rdma.c @@ -6,11 +6,27 @@ #include "hfi.h" #include "qp.h" +#include "rc.h" #include "verbs.h" #include "tid_rdma.h" #include "exp_rcv.h" #include "trace.h" +/** + * DOC: TID RDMA READ protocol + * + * This is an end-to-end protocol at the hfi1 level between two nodes that + * improves performance by avoiding data copy on the requester side. It + * converts a qualified RDMA READ request into a TID RDMA READ request on + * the requester side and thereafter handles the request and response + * differently. To be qualified, the RDMA READ request should meet the + * following: + * -- The total data length should be greater than 256K; + * -- The total data length should be a multiple of 4K page size; + * -- Each local scatter-gather entry should be 4K page aligned; + * -- Each local scatter-gather entry should be a multiple of 4K page size; + */ + #define RCV_TID_FLOW_TABLE_CTRL_FLOW_VALID_SMASK BIT_ULL(32) #define RCV_TID_FLOW_TABLE_CTRL_HDR_SUPP_EN_SMASK BIT_ULL(33) #define RCV_TID_FLOW_TABLE_CTRL_KEEP_AFTER_SEQ_ERR_SMASK BIT_ULL(34) @@ -18,6 +34,9 @@ #define RCV_TID_FLOW_TABLE_STATUS_SEQ_MISMATCH_SMASK BIT_ULL(37) #define RCV_TID_FLOW_TABLE_STATUS_GEN_MISMATCH_SMASK BIT_ULL(38) +/* Maximum number of packets within a flow generation. */ +#define MAX_TID_FLOW_PSN BIT(HFI1_KDETH_BTH_SEQ_SHIFT) + #define GENERATION_MASK 0xFFFFF static u32 mask_generation(u32 a) @@ -45,6 +64,9 @@ static u32 mask_generation(u32 a) #define MAX_EXPECTED_PAGES (MAX_EXPECTED_BUFFER / PAGE_SIZE) +#define TID_RDMA_DESTQP_FLOW_SHIFT 11 +#define TID_RDMA_DESTQP_FLOW_MASK 0x1f + #define TID_OPFN_QP_CTXT_MASK 0xff #define TID_OPFN_QP_CTXT_SHIFT 56 #define TID_OPFN_QP_KDETH_MASK 0xff @@ -1597,3 +1619,181 @@ u64 hfi1_access_sw_tid_wait(const struct cntr_entry *entry, return dd->verbs_dev.n_tidwait; } + +/* TID RDMA READ functions */ +u32 hfi1_build_tid_rdma_read_packet(struct rvt_swqe *wqe, + struct ib_other_headers *ohdr, u32 *bth1, + u32 *bth2, u32 *len) +{ + struct tid_rdma_request *req = wqe_to_tid_req(wqe); + struct tid_rdma_flow *flow = &req->flows[req->flow_idx]; + struct rvt_qp *qp = req->qp; + struct hfi1_qp_priv *qpriv = qp->priv; + struct hfi1_swqe_priv *wpriv = wqe->priv; + struct tid_rdma_read_req *rreq = &ohdr->u.tid_rdma.r_req; + struct tid_rdma_params *remote; + u32 req_len = 0; + void *req_addr = NULL; + + /* This is the IB psn used to send the request */ + *bth2 = mask_psn(flow->flow_state.ib_spsn + flow->pkt); + + /* TID Entries for TID RDMA READ payload */ + req_addr = &flow->tid_entry[flow->tid_idx]; + req_len = sizeof(*flow->tid_entry) * + (flow->tidcnt - flow->tid_idx); + + memset(&ohdr->u.tid_rdma.r_req, 0, sizeof(ohdr->u.tid_rdma.r_req)); + wpriv->ss.sge.vaddr = req_addr; + wpriv->ss.sge.sge_length = req_len; + wpriv->ss.sge.length = wpriv->ss.sge.sge_length; + /* + * We can safely zero these out. Since the first SGE covers the + * entire packet, nothing else should even look at the MR. + */ + wpriv->ss.sge.mr = NULL; + wpriv->ss.sge.m = 0; + wpriv->ss.sge.n = 0; + + wpriv->ss.sg_list = NULL; + wpriv->ss.total_len = wpriv->ss.sge.sge_length; + wpriv->ss.num_sge = 1; + + /* Construct the TID RDMA READ REQ packet header */ + rcu_read_lock(); + remote = rcu_dereference(qpriv->tid_rdma.remote); + + KDETH_RESET(rreq->kdeth0, KVER, 0x1); + KDETH_RESET(rreq->kdeth1, JKEY, remote->jkey); + rreq->reth.vaddr = cpu_to_be64(wqe->rdma_wr.remote_addr + + req->cur_seg * req->seg_len + flow->sent); + rreq->reth.rkey = cpu_to_be32(wqe->rdma_wr.rkey); + rreq->reth.length = cpu_to_be32(*len); + rreq->tid_flow_psn = + cpu_to_be32((flow->flow_state.generation << + HFI1_KDETH_BTH_SEQ_SHIFT) | + ((flow->flow_state.spsn + flow->pkt) & + HFI1_KDETH_BTH_SEQ_MASK)); + rreq->tid_flow_qp = + cpu_to_be32(qpriv->tid_rdma.local.qp | + ((flow->idx & TID_RDMA_DESTQP_FLOW_MASK) << + TID_RDMA_DESTQP_FLOW_SHIFT) | + qpriv->rcd->ctxt); + rreq->verbs_qp = cpu_to_be32(qp->remote_qpn); + *bth1 &= ~RVT_QPN_MASK; + *bth1 |= remote->qp; + *bth2 |= IB_BTH_REQ_ACK; + rcu_read_unlock(); + + /* We are done with this segment */ + flow->sent += *len; + req->cur_seg++; + qp->s_state = TID_OP(READ_REQ); + req->ack_pending++; + req->flow_idx = (req->flow_idx + 1) & (MAX_FLOWS - 1); + qpriv->pending_tid_r_segs++; + qp->s_num_rd_atomic++; + + /* Set the TID RDMA READ request payload size */ + *len = req_len; + + return sizeof(ohdr->u.tid_rdma.r_req) / sizeof(u32); +} + +/* + * @len: contains the data length to read upon entry and the read request + * payload length upon exit. + */ +u32 hfi1_build_tid_rdma_read_req(struct rvt_qp *qp, struct rvt_swqe *wqe, + struct ib_other_headers *ohdr, u32 *bth1, + u32 *bth2, u32 *len) + __must_hold(&qp->s_lock) +{ + struct hfi1_qp_priv *qpriv = qp->priv; + struct tid_rdma_request *req = wqe_to_tid_req(wqe); + struct tid_rdma_flow *flow = NULL; + u32 hdwords = 0; + bool last; + bool retry = true; + u32 npkts = rvt_div_round_up_mtu(qp, *len); + + /* + * Check sync conditions. Make sure that there are no pending + * segments before freeing the flow. + */ +sync_check: + if (req->state == TID_REQUEST_SYNC) { + if (qpriv->pending_tid_r_segs) + goto done; + + hfi1_kern_clear_hw_flow(req->rcd, qp); + req->state = TID_REQUEST_ACTIVE; + } + + /* + * If the request for this segment is resent, the tid resources should + * have been allocated before. In this case, req->flow_idx should + * fall behind req->setup_head. + */ + if (req->flow_idx == req->setup_head) { + retry = false; + if (req->state == TID_REQUEST_RESEND) { + /* + * This is the first new segment for a request whose + * earlier segments have been re-sent. We need to + * set up the sge pointer correctly. + */ + restart_sge(&qp->s_sge, wqe, req->s_next_psn, + qp->pmtu); + req->isge = 0; + req->state = TID_REQUEST_ACTIVE; + } + + /* + * Check sync. The last PSN of each generation is reserved for + * RESYNC. + */ + if ((qpriv->flow_state.psn + npkts) > MAX_TID_FLOW_PSN - 1) { + req->state = TID_REQUEST_SYNC; + goto sync_check; + } + + /* Allocate the flow if not yet */ + if (hfi1_kern_setup_hw_flow(qpriv->rcd, qp)) + goto done; + + /* + * The following call will advance req->setup_head after + * allocating the tid entries. + */ + if (hfi1_kern_exp_rcv_setup(req, &qp->s_sge, &last)) { + req->state = TID_REQUEST_QUEUED; + + /* + * We don't have resources for this segment. The QP has + * already been queued. + */ + goto done; + } + } + + /* req->flow_idx should only be one slot behind req->setup_head */ + flow = &req->flows[req->flow_idx]; + flow->pkt = 0; + flow->tid_idx = 0; + flow->sent = 0; + if (!retry) { + /* Set the first and last IB PSN for the flow in use.*/ + flow->flow_state.ib_spsn = req->s_next_psn; + flow->flow_state.ib_lpsn = + flow->flow_state.ib_spsn + flow->npkts - 1; + } + + /* Calculate the next segment start psn.*/ + req->s_next_psn += flow->npkts; + + /* Build the packet header */ + hdwords = hfi1_build_tid_rdma_read_packet(wqe, ohdr, bth1, bth2, len); +done: + return hdwords; +} |