diff options
author | Mike Marciniszyn <mike.marciniszyn@intel.com> | 2016-02-14 12:10:04 -0800 |
---|---|---|
committer | Doug Ledford <dledford@redhat.com> | 2016-03-10 20:38:07 -0500 |
commit | 46a80d62e6e0ccfc9d8a05c5b773405b84a4afd7 (patch) | |
tree | 077ea38ac2f7fd75c1334deadcc141ad6753a009 /drivers/infiniband/sw | |
parent | 20f333b61300fa658952713ca9b8b4b72bbaed9f (diff) | |
download | linux-46a80d62e6e0ccfc9d8a05c5b773405b84a4afd7.tar.bz2 |
IB/qib, staging/rdma/hfi1: add s_hlock for use in post send
This patch adds an additional lock to reduce contention on the s_lock.
This lock is used in post_send() so that the post_send is not
serialized with the send engine and other send related processing.
To do this the s_next_psn is now maintained on post_send() while
post_send() related fields are moved to a new cache line. There is
an s_avail maintained for the post_send() to mitigate trading cache
lines with the send engine. The lock is released/acquired around
releasing the just built packet to the egress mechanism.
Reviewed-by: Jubin John <jubin.john@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/sw')
-rw-r--r-- | drivers/infiniband/sw/rdmavt/qp.c | 97 |
1 files changed, 76 insertions, 21 deletions
diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index 7dc837c6554b..522404ac7c38 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -401,6 +401,7 @@ void rvt_reset_qp(struct rvt_dev_info *rdi, struct rvt_qp *qp, rdi->driver_f.flush_qp_waiters(qp); qp->s_flags &= ~(RVT_S_TIMER | RVT_S_ANY_WAIT); spin_unlock(&qp->s_lock); + spin_unlock(&qp->s_hlock); spin_unlock_irq(&qp->r_lock); /* Stop the send queue and the retry timer */ @@ -415,6 +416,7 @@ void rvt_reset_qp(struct rvt_dev_info *rdi, struct rvt_qp *qp, /* grab the lock b/c it was locked at call time */ spin_lock_irq(&qp->r_lock); + spin_lock(&qp->s_hlock); spin_lock(&qp->s_lock); rvt_clear_mr_refs(qp, 1); @@ -610,6 +612,7 @@ struct ib_qp *rvt_create_qp(struct ib_pd *ibpd, * except for qp->ibqp.qp_num. */ spin_lock_init(&qp->r_lock); + spin_lock_init(&qp->s_hlock); spin_lock_init(&qp->s_lock); spin_lock_init(&qp->r_rq.lock); atomic_set(&qp->refcount, 0); @@ -620,6 +623,7 @@ struct ib_qp *rvt_create_qp(struct ib_pd *ibpd, qp->state = IB_QPS_RESET; qp->s_wq = swq; qp->s_size = init_attr->cap.max_send_wr + 1; + qp->s_avail = init_attr->cap.max_send_wr; qp->s_max_sge = init_attr->cap.max_send_sge; if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR) qp->s_flags = RVT_S_SIGNAL_REQ_WR; @@ -779,6 +783,7 @@ void rvt_clear_mr_refs(struct rvt_qp *qp, int clr_sends) wqe->ud_wr.ah)->refcount); if (++qp->s_last >= qp->s_size) qp->s_last = 0; + smp_wmb(); /* see qp_set_savail */ } if (qp->s_rdma_mr) { rvt_put_mr(qp->s_rdma_mr); @@ -833,7 +838,7 @@ int rvt_error_qp(struct rvt_qp *qp, enum ib_wc_status err) rdi->driver_f.notify_error_qp(qp); /* Schedule the sending tasklet to drain the send work queue. */ - if (qp->s_last != qp->s_head) + if (ACCESS_ONCE(qp->s_last) != qp->s_head) rdi->driver_f.schedule_send(qp); rvt_clear_mr_refs(qp, 0); @@ -979,6 +984,7 @@ int rvt_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, link = rdma_port_get_link_layer(ibqp->device, qp->port_num); spin_lock_irq(&qp->r_lock); + spin_lock(&qp->s_hlock); spin_lock(&qp->s_lock); cur_state = attr_mask & IB_QP_CUR_STATE ? @@ -1151,6 +1157,7 @@ int rvt_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, if (attr_mask & IB_QP_PATH_MTU) { qp->pmtu = rdi->driver_f.mtu_from_qp(rdi, qp, pmtu); qp->path_mtu = rdi->driver_f.mtu_to_path_mtu(qp->pmtu); + qp->log_pmtu = ilog2(qp->pmtu); } if (attr_mask & IB_QP_RETRY_CNT) { @@ -1186,6 +1193,7 @@ int rvt_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, rdi->driver_f.modify_qp(qp, attr, attr_mask, udata); spin_unlock(&qp->s_lock); + spin_unlock(&qp->s_hlock); spin_unlock_irq(&qp->r_lock); if (cur_state == IB_QPS_RESET && new_state == IB_QPS_INIT) @@ -1207,6 +1215,7 @@ int rvt_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, inval: spin_unlock(&qp->s_lock); + spin_unlock(&qp->s_hlock); spin_unlock_irq(&qp->r_lock); return -EINVAL; } @@ -1226,9 +1235,11 @@ int rvt_destroy_qp(struct ib_qp *ibqp) struct rvt_dev_info *rdi = ib_to_rvt(ibqp->device); spin_lock_irq(&qp->r_lock); + spin_lock(&qp->s_hlock); spin_lock(&qp->s_lock); rvt_reset_qp(rdi, qp, ibqp->qp_type); spin_unlock(&qp->s_lock); + spin_unlock(&qp->s_hlock); spin_unlock_irq(&qp->r_lock); /* qpn is now available for use again */ @@ -1358,6 +1369,28 @@ int rvt_post_recv(struct ib_qp *ibqp, struct ib_recv_wr *wr, } /** + * qp_get_savail - return number of avail send entries + * + * @qp - the qp + * + * This assumes the s_hlock is held but the s_last + * qp variable is uncontrolled. + */ +static inline u32 qp_get_savail(struct rvt_qp *qp) +{ + u32 slast; + u32 ret; + + smp_read_barrier_depends(); /* see rc.c */ + slast = ACCESS_ONCE(qp->s_last); + if (qp->s_head >= slast) + ret = qp->s_size - (qp->s_head - slast); + else + ret = slast - qp->s_head; + return ret - 1; +} + +/** * rvt_post_one_wr - post one RC, UC, or UD send work request * @qp: the QP to post on * @wr: the work request to send @@ -1372,6 +1405,8 @@ static int rvt_post_one_wr(struct rvt_qp *qp, struct ib_send_wr *wr) struct rvt_lkey_table *rkt; struct rvt_pd *pd; struct rvt_dev_info *rdi = ib_to_rvt(qp->ibqp.device); + u8 log_pmtu; + int ret; /* IB spec says that num_sge == 0 is OK. */ if (unlikely(wr->num_sge > qp->s_max_sge)) @@ -1403,16 +1438,16 @@ static int rvt_post_one_wr(struct rvt_qp *qp, struct ib_send_wr *wr) } else if (wr->opcode >= IB_WR_RDMA_READ && !qp->s_max_rd_atomic) { return -EINVAL; } - + /* check for avail */ + if (unlikely(!qp->s_avail)) { + qp->s_avail = qp_get_savail(qp); + WARN_ON(qp->s_avail > (qp->s_size - 1)); + if (!qp->s_avail) + return -ENOMEM; + } next = qp->s_head + 1; if (next >= qp->s_size) next = 0; - if (next == qp->s_last) - return -ENOMEM; - - if (rdi->driver_f.check_send_wr && - rdi->driver_f.check_send_wr(qp, wr)) - return -EINVAL; rkt = &rdi->lkey_table; pd = ibpd_to_rvtpd(qp->ibqp.pd); @@ -1444,21 +1479,39 @@ static int rvt_post_one_wr(struct rvt_qp *qp, struct ib_send_wr *wr) continue; ok = rvt_lkey_ok(rkt, pd, &wqe->sg_list[j], &wr->sg_list[i], acc); - if (!ok) + if (!ok) { + ret = -EINVAL; goto bail_inval_free; + } wqe->length += length; j++; } wqe->wr.num_sge = j; } - if (qp->ibqp.qp_type == IB_QPT_UC || - qp->ibqp.qp_type == IB_QPT_RC) { - if (wqe->length > 0x80000000U) + + /* general part of wqe valid - allow for driver checks */ + if (rdi->driver_f.check_send_wqe) { + ret = rdi->driver_f.check_send_wqe(qp, wqe); + if (ret) goto bail_inval_free; - } else { + } + + log_pmtu = qp->log_pmtu; + if (qp->ibqp.qp_type != IB_QPT_UC && + qp->ibqp.qp_type != IB_QPT_RC) { + struct rvt_ah *ah = ibah_to_rvtah(wqe->ud_wr.ah); + + log_pmtu = ah->log_pmtu; atomic_inc(&ibah_to_rvtah(ud_wr(wr)->ah)->refcount); } + wqe->ssn = qp->s_ssn++; + wqe->psn = qp->s_next_psn; + wqe->lpsn = wqe->psn + + (wqe->length ? ((wqe->length - 1) >> log_pmtu) : 0); + qp->s_next_psn = wqe->lpsn + 1; + smp_wmb(); /* see request builders */ + qp->s_avail--; qp->s_head = next; return 0; @@ -1470,7 +1523,7 @@ bail_inval_free: rvt_put_mr(sge->mr); } - return -EINVAL; + return ret; } /** @@ -1491,14 +1544,14 @@ int rvt_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, unsigned nreq = 0; int err = 0; - spin_lock_irqsave(&qp->s_lock, flags); + spin_lock_irqsave(&qp->s_hlock, flags); /* * Ensure QP state is such that we can send. If not bail out early, * there is no need to do this every time we post a send. */ if (unlikely(!(ib_rvt_state_ops[qp->state] & RVT_POST_SEND_OK))) { - spin_unlock_irqrestore(&qp->s_lock, flags); + spin_unlock_irqrestore(&qp->s_hlock, flags); return -EINVAL; } @@ -1518,11 +1571,13 @@ int rvt_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, nreq++; } bail: - if (nreq && !call_send) - rdi->driver_f.schedule_send(qp); - spin_unlock_irqrestore(&qp->s_lock, flags); - if (nreq && call_send) - rdi->driver_f.do_send(qp); + spin_unlock_irqrestore(&qp->s_hlock, flags); + if (nreq) { + if (call_send) + rdi->driver_f.schedule_send_no_lock(qp); + else + rdi->driver_f.do_send(qp); + } return err; } |