@@ -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;
+}
@@ -45,6 +45,19 @@ struct tid_flow_state {
u8 flags;
};
+enum tid_rdma_req_state {
+ TID_REQUEST_INACTIVE = 0,
+ TID_REQUEST_INIT,
+ TID_REQUEST_INIT_RESEND,
+ TID_REQUEST_ACTIVE,
+ TID_REQUEST_RESEND,
+ TID_REQUEST_RESEND_ACTIVE,
+ TID_REQUEST_QUEUED,
+ TID_REQUEST_SYNC,
+ TID_REQUEST_RNR_NAK,
+ TID_REQUEST_COMPLETE,
+};
+
struct tid_rdma_request {
struct rvt_qp *qp;
struct hfi1_ctxtdata *rcd;
@@ -60,8 +73,13 @@ struct tid_rdma_request {
u16 flow_idx; /* flow index most recently set up */
u32 seg_len;
+ u32 s_next_psn; /* IB PSN of next segment start for read */
+ u32 cur_seg; /* index of current segment */
u32 isge; /* index of "current" sge */
+ u32 ack_pending; /* num acks pending for this request */
+
+ enum tid_rdma_req_state state;
};
/*
@@ -77,6 +95,10 @@ struct flow_state {
u32 spsn; /* starting PSN in TID space */
u32 lpsn; /* last PSN in TID space */
u32 r_next_psn; /* next PSN to be received (in TID space) */
+
+ /* For tid rdma read */
+ u32 ib_spsn; /* starting PSN in Verbs space */
+ u32 ib_lpsn; /* last PSn in Verbs space */
};
struct tid_rdma_pageset {
@@ -110,11 +132,14 @@ struct tid_rdma_flow {
struct flow_state flow_state;
struct tid_rdma_request *req;
u32 length;
+ u32 sent;
u8 tnode_cnt;
u8 tidcnt;
+ u8 tid_idx;
u8 idx;
u8 npagesets;
u8 npkts;
+ u8 pkt;
struct kern_tid_node tnode[TID_RDMA_MAX_PAGES];
struct tid_rdma_pageset pagesets[TID_RDMA_MAX_PAGES];
u32 tid_entry[TID_RDMA_MAX_PAGES];
@@ -159,4 +184,11 @@ int hfi1_qp_priv_init(struct rvt_dev_info *rdi, struct rvt_qp *qp,
u64 hfi1_access_sw_tid_wait(const struct cntr_entry *entry,
void *context, int vl, int mode, u64 data);
+u32 hfi1_build_tid_rdma_read_packet(struct rvt_swqe *wqe,
+ struct ib_other_headers *ohdr,
+ u32 *bth1, u32 *bth2, u32 *len);
+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);
+
#endif /* HFI1_TID_RDMA_H */
@@ -170,12 +170,16 @@ struct hfi1_qp_priv {
struct rvt_qp *owner;
u8 hdr_type; /* 9B or 16B */
unsigned long tid_timer_timeout_jiffies;
+
+ /* For TID RDMA READ */
+ u32 pending_tid_r_segs; /* Num of pending tid read segments */
u16 pkts_ps; /* packets per segment */
u8 timeout_shift; /* account for number of packets per segment */
};
struct hfi1_swqe_priv {
struct tid_rdma_request tid_req;
+ struct rvt_sge_state ss; /* Used for TID RDMA READ Request */
};
struct hfi1_ack_priv {
@@ -331,6 +335,11 @@ static inline u32 delta_psn(u32 a, u32 b)
return (((int)a - (int)b) << PSN_SHIFT) >> PSN_SHIFT;
}
+static inline struct tid_rdma_request *wqe_to_tid_req(struct rvt_swqe *wqe)
+{
+ return &((struct hfi1_swqe_priv *)wqe->priv)->tid_req;
+}
+
/*
* Look through all the active flows for a TID RDMA request and find
* the one (if it exists) that contains the specified PSN.
@@ -1,5 +1,5 @@
/*
- * Copyright(c) 2016 Intel Corporation.
+ * Copyright(c) 2016 - 2018 Intel Corporation.
*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
@@ -100,6 +100,8 @@ struct ib_atomic_eth {
__be64 compare_data; /* potentially unaligned */
} __packed;
+#include <rdma/tid_rdma_defs.h>
+
union ib_ehdrs {
struct {
__be32 deth[2];
@@ -117,6 +119,11 @@ struct ib_atomic_eth {
__be32 aeth;
__be32 ieth;
struct ib_atomic_eth atomic_eth;
+ /* TID RDMA headers */
+ union {
+ struct tid_rdma_read_req r_req;
+ struct tid_rdma_read_resp r_rsp;
+ } tid_rdma;
} __packed;
struct ib_other_headers {
new file mode 100644
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
+/*
+ * Copyright(c) 2018 Intel Corporation.
+ *
+ */
+
+#ifndef TID_RDMA_DEFS_H
+#define TID_RDMA_DEFS_H
+
+#include <rdma/ib_pack.h>
+
+struct tid_rdma_read_req {
+ __le32 kdeth0;
+ __le32 kdeth1;
+ struct ib_reth reth;
+ __be32 tid_flow_psn;
+ __be32 tid_flow_qp;
+ __be32 verbs_qp;
+};
+
+struct tid_rdma_read_resp {
+ __le32 kdeth0;
+ __le32 kdeth1;
+ __be32 aeth;
+ __be32 reserved[4];
+ __be32 verbs_psn;
+ __be32 verbs_qp;
+};
+
+/*
+ * TID RDMA Opcodes
+ */
+#define IB_OPCODE_TID_RDMA 0xe0
+enum {
+ IB_OPCODE_READ_REQ = 0x4,
+ IB_OPCODE_READ_RESP = 0x5,
+
+ IB_OPCODE(TID_RDMA, READ_REQ),
+ IB_OPCODE(TID_RDMA, READ_RESP),
+};
+
+#define TID_OP(x) IB_OPCODE_TID_RDMA_##x
+
+/*
+ * Define TID RDMA specific WR opcodes. The ib_wr_opcode
+ * enum already provides some reserved values for use by
+ * low level drivers. Two of those are used but renamed
+ * to be more descriptive.
+ */
+#define IB_WR_TID_RDMA_READ IB_WR_RESERVED2
+
+#endif /* TID_RDMA_DEFS_H */