X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lnet%2Flnet%2Flib-move.c;h=c36a88675076a8679f835dc997fb99890371b571;hp=a50e2af0477a77326dc3ea9251b43d92d10d3e83;hb=4c4c327b25f3414f20a9ae600e7311f1aa3a866d;hpb=cda0a8abf5bbfe0f3fc12454c1d3d8efdcbda17c diff --git a/lnet/lnet/lib-move.c b/lnet/lnet/lib-move.c index a50e2af..c36a886 100644 --- a/lnet/lnet/lib-move.c +++ b/lnet/lnet/lib-move.c @@ -46,6 +46,23 @@ static int local_nid_dist_zero = 1; module_param(local_nid_dist_zero, int, 0444); MODULE_PARM_DESC(local_nid_dist_zero, "Reserved"); +struct lnet_send_data { + struct lnet_ni *sd_best_ni; + struct lnet_peer_ni *sd_best_lpni; + struct lnet_peer_ni *sd_final_dst_lpni; + struct lnet_peer *sd_peer; + struct lnet_peer *sd_gw_peer; + struct lnet_peer_ni *sd_gw_lpni; + struct lnet_peer_net *sd_peer_net; + struct lnet_msg *sd_msg; + lnet_nid_t sd_dst_nid; + lnet_nid_t sd_src_nid; + lnet_nid_t sd_rtr_nid; + int sd_cpt; + int sd_md_cpt; + __u32 sd_send_case; +}; + static inline struct lnet_comm_count * get_stats_counts(struct lnet_element_stats *stats, enum lnet_stats_type stats_type) @@ -148,7 +165,7 @@ lnet_fail_nid(lnet_nid_t nid, unsigned int threshold) struct lnet_test_peer *tp; struct list_head *el; struct list_head *next; - struct list_head cull; + LIST_HEAD(cull); /* NB: use lnet_net_lock(0) to serialize operations on test peers */ if (threshold != 0) { @@ -166,9 +183,6 @@ lnet_fail_nid(lnet_nid_t nid, unsigned int threshold) return 0; } - /* removing entries */ - INIT_LIST_HEAD(&cull); - lnet_net_lock(0); list_for_each_safe(el, next, &the_lnet.ln_test_peers) { @@ -177,8 +191,7 @@ lnet_fail_nid(lnet_nid_t nid, unsigned int threshold) if (tp->tp_threshold == 0 || /* needs culling anyway */ nid == LNET_NID_ANY || /* removing all entries */ tp->tp_nid == nid) { /* matched this one */ - list_del(&tp->tp_list); - list_add(&tp->tp_list, &cull); + list_move(&tp->tp_list, &cull); } } @@ -199,10 +212,8 @@ fail_peer (lnet_nid_t nid, int outgoing) struct lnet_test_peer *tp; struct list_head *el; struct list_head *next; - struct list_head cull; - int fail = 0; - - INIT_LIST_HEAD(&cull); + LIST_HEAD(cull); + int fail = 0; /* NB: use lnet_net_lock(0) to serialize operations on test peers */ lnet_net_lock(0); @@ -216,8 +227,7 @@ fail_peer (lnet_nid_t nid, int outgoing) /* only cull zombies on outgoing tests, * since we may be at interrupt priority on * incoming messages. */ - list_del(&tp->tp_list); - list_add(&tp->tp_list, &cull); + list_move(&tp->tp_list, &cull); } continue; } @@ -231,8 +241,7 @@ fail_peer (lnet_nid_t nid, int outgoing) if (outgoing && tp->tp_threshold == 0) { /* see above */ - list_del(&tp->tp_list); - list_add(&tp->tp_list, &cull); + list_move(&tp->tp_list, &cull); } } break; @@ -270,7 +279,7 @@ lnet_copy_iov2iov(unsigned int ndiov, struct kvec *diov, unsigned int doffset, unsigned int nob) { /* NB diov, siov are READ-ONLY */ - unsigned int this_nob; + unsigned int this_nob; if (nob == 0) return; @@ -296,9 +305,9 @@ lnet_copy_iov2iov(unsigned int ndiov, struct kvec *diov, unsigned int doffset, do { LASSERT(ndiov > 0); LASSERT(nsiov > 0); - this_nob = MIN(diov->iov_len - doffset, - siov->iov_len - soffset); - this_nob = MIN(this_nob, nob); + this_nob = min3((unsigned int)diov->iov_len - doffset, + (unsigned int)siov->iov_len - soffset, + nob); memcpy((char *)diov->iov_base + doffset, (char *)siov->iov_base + soffset, this_nob); @@ -418,9 +427,9 @@ lnet_copy_kiov2kiov(unsigned int ndiov, lnet_kiov_t *diov, unsigned int doffset, do { LASSERT(ndiov > 0); LASSERT(nsiov > 0); - this_nob = MIN(diov->kiov_len - doffset, - siov->kiov_len - soffset); - this_nob = MIN(this_nob, nob); + this_nob = min3(diov->kiov_len - doffset, + siov->kiov_len - soffset, + nob); if (daddr == NULL) daddr = ((char *)kmap(diov->kiov_page)) + @@ -499,9 +508,9 @@ lnet_copy_kiov2iov (unsigned int niov, struct kvec *iov, unsigned int iovoffset, do { LASSERT(niov > 0); LASSERT(nkiov > 0); - this_nob = MIN(iov->iov_len - iovoffset, - kiov->kiov_len - kiovoffset); - this_nob = MIN(this_nob, nob); + this_nob = min3((unsigned int)iov->iov_len - iovoffset, + (unsigned int)kiov->kiov_len - kiovoffset, + nob); if (addr == NULL) addr = ((char *)kmap(kiov->kiov_page)) + @@ -569,9 +578,9 @@ lnet_copy_iov2kiov(unsigned int nkiov, lnet_kiov_t *kiov, unsigned int kiovoffse do { LASSERT(nkiov > 0); LASSERT(niov > 0); - this_nob = MIN(kiov->kiov_len - kiovoffset, - iov->iov_len - iovoffset); - this_nob = MIN(this_nob, nob); + this_nob = min3((unsigned int)kiov->kiov_len - kiovoffset, + (unsigned int)iov->iov_len - iovoffset, + nob); if (addr == NULL) addr = ((char *)kmap(kiov->kiov_page)) + @@ -740,15 +749,17 @@ static void lnet_ni_send(struct lnet_ni *ni, struct lnet_msg *msg) { void *priv = msg->msg_private; - int rc; + int rc; LASSERT (!in_interrupt ()); LASSERT (LNET_NETTYP(LNET_NIDNET(ni->ni_nid)) == LOLND || (msg->msg_txcredit && msg->msg_peertxcredit)); rc = (ni->ni_net->net_lnd->lnd_send)(ni, priv, msg); - if (rc < 0) + if (rc < 0) { + msg->msg_no_resend = true; lnet_finalize(msg, rc); + } } static int @@ -775,120 +786,55 @@ lnet_ni_eager_recv(struct lnet_ni *ni, struct lnet_msg *msg) return rc; } -/* - * This function can be called from two paths: - * 1. when sending a message - * 2. when decommiting a message (lnet_msg_decommit_tx()) - * In both these cases the peer_ni should have it's reference count - * acquired by the caller and therefore it is safe to drop the spin - * lock before calling lnd_query() - */ -static void -lnet_ni_query_locked(struct lnet_ni *ni, struct lnet_peer_ni *lp) -{ - cfs_time_t last_alive = 0; - int cpt = lnet_cpt_of_nid_locked(lp->lpni_nid, ni); - - LASSERT(lnet_peer_aliveness_enabled(lp)); - LASSERT(ni->ni_net->net_lnd->lnd_query != NULL); - - lnet_net_unlock(cpt); - (ni->ni_net->net_lnd->lnd_query)(ni, lp->lpni_nid, &last_alive); - lnet_net_lock(cpt); - - lp->lpni_last_query = cfs_time_current(); - - if (last_alive != 0) /* NI has updated timestamp */ - lp->lpni_last_alive = last_alive; -} - -/* NB: always called with lnet_net_lock held */ -static inline int -lnet_peer_is_alive (struct lnet_peer_ni *lp, cfs_time_t now) +static bool +lnet_is_peer_deadline_passed(struct lnet_peer_ni *lpni, time64_t now) { - int alive; - cfs_time_t deadline; - - LASSERT (lnet_peer_aliveness_enabled(lp)); - - /* - * Trust lnet_notify() if it has more recent aliveness news, but - * ignore the initial assumed death (see lnet_peers_start_down()). - */ - spin_lock(&lp->lpni_lock); - if (!lp->lpni_alive && lp->lpni_alive_count > 0 && - cfs_time_aftereq(lp->lpni_timestamp, lp->lpni_last_alive)) { - spin_unlock(&lp->lpni_lock); - return 0; - } + time64_t deadline; - deadline = - cfs_time_add(lp->lpni_last_alive, - cfs_time_seconds(lp->lpni_net->net_tunables. - lct_peer_timeout)); - alive = cfs_time_after(deadline, now); + deadline = lpni->lpni_last_alive + + lpni->lpni_net->net_tunables.lct_peer_timeout; /* - * Update obsolete lp_alive except for routers assumed to be dead - * initially, because router checker would update aliveness in this - * case, and moreover lpni_last_alive at peer creation is assumed. + * assume peer_ni is alive as long as we're within the configured + * peer timeout */ - if (alive && !lp->lpni_alive && - !(lnet_isrouter(lp) && lp->lpni_alive_count == 0)) { - spin_unlock(&lp->lpni_lock); - lnet_notify_locked(lp, 0, 1, lp->lpni_last_alive); - } else { - spin_unlock(&lp->lpni_lock); - } + if (deadline > now) + return false; - return alive; + return true; } - /* NB: returns 1 when alive, 0 when dead, negative when error; * may drop the lnet_net_lock */ static int -lnet_peer_alive_locked (struct lnet_ni *ni, struct lnet_peer_ni *lp) +lnet_peer_alive_locked(struct lnet_ni *ni, struct lnet_peer_ni *lpni, + struct lnet_msg *msg) { - cfs_time_t now = cfs_time_current(); + time64_t now = ktime_get_seconds(); - if (!lnet_peer_aliveness_enabled(lp)) + if (!lnet_peer_aliveness_enabled(lpni)) return -ENODEV; - if (lnet_peer_is_alive(lp, now)) - return 1; - /* - * Peer appears dead, but we should avoid frequent NI queries (at - * most once per lnet_queryinterval seconds). + * If we're resending a message, let's attempt to send it even if + * the peer is down to fulfill our resend quota on the message */ - if (lp->lpni_last_query != 0) { - static const int lnet_queryinterval = 1; - - cfs_time_t next_query = - cfs_time_add(lp->lpni_last_query, - cfs_time_seconds(lnet_queryinterval)); - - if (cfs_time_before(now, next_query)) { - if (lp->lpni_alive) - CWARN("Unexpected aliveness of peer %s: " - "%d < %d (%d/%d)\n", - libcfs_nid2str(lp->lpni_nid), - (int)now, (int)next_query, - lnet_queryinterval, - lp->lpni_net->net_tunables.lct_peer_timeout); - return 0; - } - } + if (msg->msg_retry_count > 0) + return 1; - /* query NI for latest aliveness news */ - lnet_ni_query_locked(ni, lp); + /* try and send recovery messages irregardless */ + if (msg->msg_recovery) + return 1; - if (lnet_peer_is_alive(lp, now)) + /* always send any responses */ + if (msg->msg_type == LNET_MSG_ACK || + msg->msg_type == LNET_MSG_REPLY) return 1; - lnet_notify_locked(lp, 0, 0, lp->lpni_last_alive); - return 0; + if (!lnet_is_peer_deadline_passed(lpni, now)) + return true; + + return lnet_is_peer_ni_alive(lpni); } /** @@ -914,12 +860,15 @@ lnet_post_send_locked(struct lnet_msg *msg, int do_send) LASSERT(!do_send || msg->msg_tx_delayed); LASSERT(!msg->msg_receiving); LASSERT(msg->msg_tx_committed); + /* can't get here if we're sending to the loopback interface */ + LASSERT(lp->lpni_nid != the_lnet.ln_loni->ni_nid); /* NB 'lp' is always the next hop */ if ((msg->msg_target.pid & LNET_PID_USERFLAG) == 0 && - lnet_peer_alive_locked(ni, lp) == 0) { - the_lnet.ln_counters[cpt]->drop_count++; - the_lnet.ln_counters[cpt]->drop_length += msg->msg_len; + lnet_peer_alive_locked(ni, lp, msg) == 0) { + the_lnet.ln_counters[cpt]->lct_common.lcc_drop_count++; + the_lnet.ln_counters[cpt]->lct_common.lcc_drop_length += + msg->msg_len; lnet_net_unlock(cpt); if (msg->msg_txpeer) lnet_incr_stats(&msg->msg_txpeer->lpni_stats, @@ -932,6 +881,7 @@ lnet_post_send_locked(struct lnet_msg *msg, int do_send) CNETERR("Dropping message for %s: peer not alive\n", libcfs_id2str(msg->msg_target)); + msg->msg_health_status = LNET_MSG_STATUS_REMOTE_DROPPED; if (do_send) lnet_finalize(msg, -EHOSTUNREACH); @@ -946,8 +896,12 @@ lnet_post_send_locked(struct lnet_msg *msg, int do_send) CNETERR("Aborting message for %s: LNetM[DE]Unlink() already " "called on the MD/ME.\n", libcfs_id2str(msg->msg_target)); - if (do_send) + if (do_send) { + msg->msg_no_resend = true; + CDEBUG(D_NET, "msg %p to %s canceled and will not be resent\n", + msg, libcfs_id2str(msg->msg_target)); lnet_finalize(msg, -ECANCELED); + } lnet_net_lock(cpt); return -ECANCELED; @@ -992,6 +946,9 @@ lnet_post_send_locked(struct lnet_msg *msg, int do_send) } } + /* unset the tx_delay flag as we're going to send it now */ + msg->msg_tx_delayed = 0; + if (do_send) { lnet_net_unlock(cpt); lnet_ni_send(ni, msg); @@ -1028,39 +985,47 @@ lnet_post_routed_recv_locked(struct lnet_msg *msg, int do_recv) * sets do_recv FALSE and I don't do the unlock/send/lock bit. * I return LNET_CREDIT_WAIT if msg blocked and LNET_CREDIT_OK if * received or OK to receive */ - struct lnet_peer_ni *lp = msg->msg_rxpeer; + struct lnet_peer_ni *lpni = msg->msg_rxpeer; + struct lnet_peer *lp; struct lnet_rtrbufpool *rbp; struct lnet_rtrbuf *rb; - LASSERT (msg->msg_iov == NULL); - LASSERT (msg->msg_kiov == NULL); - LASSERT (msg->msg_niov == 0); - LASSERT (msg->msg_routing); - LASSERT (msg->msg_receiving); - LASSERT (!msg->msg_sending); + LASSERT(msg->msg_iov == NULL); + LASSERT(msg->msg_kiov == NULL); + LASSERT(msg->msg_niov == 0); + LASSERT(msg->msg_routing); + LASSERT(msg->msg_receiving); + LASSERT(!msg->msg_sending); + LASSERT(lpni->lpni_peer_net); + LASSERT(lpni->lpni_peer_net->lpn_peer); + + lp = lpni->lpni_peer_net->lpn_peer; /* non-lnet_parse callers only receive delayed messages */ LASSERT(!do_recv || msg->msg_rx_delayed); if (!msg->msg_peerrtrcredit) { - spin_lock(&lp->lpni_lock); - LASSERT((lp->lpni_rtrcredits < 0) == - !list_empty(&lp->lpni_rtrq)); + /* lpni_lock protects the credit manipulation */ + spin_lock(&lpni->lpni_lock); + /* lp_lock protects the lp_rtrq */ + spin_lock(&lp->lp_lock); msg->msg_peerrtrcredit = 1; - lp->lpni_rtrcredits--; - if (lp->lpni_rtrcredits < lp->lpni_minrtrcredits) - lp->lpni_minrtrcredits = lp->lpni_rtrcredits; + lpni->lpni_rtrcredits--; + if (lpni->lpni_rtrcredits < lpni->lpni_minrtrcredits) + lpni->lpni_minrtrcredits = lpni->lpni_rtrcredits; - if (lp->lpni_rtrcredits < 0) { + if (lpni->lpni_rtrcredits < 0) { /* must have checked eager_recv before here */ LASSERT(msg->msg_rx_ready_delay); msg->msg_rx_delayed = 1; - list_add_tail(&msg->msg_list, &lp->lpni_rtrq); - spin_unlock(&lp->lpni_lock); + list_add_tail(&msg->msg_list, &lp->lp_rtrq); + spin_unlock(&lp->lp_lock); + spin_unlock(&lpni->lpni_lock); return LNET_CREDIT_WAIT; } - spin_unlock(&lp->lpni_lock); + spin_unlock(&lp->lp_lock); + spin_unlock(&lpni->lpni_lock); } rbp = lnet_msg2bufpool(msg); @@ -1087,6 +1052,9 @@ lnet_post_routed_recv_locked(struct lnet_msg *msg, int do_recv) msg->msg_niov = rbp->rbp_npages; msg->msg_kiov = &rb->rb_kiov[0]; + /* unset the msg-rx_delayed flag since we're receiving the message */ + msg->msg_rx_delayed = 0; + if (do_recv) { int cpt = msg->msg_rx_cpt; @@ -1186,15 +1154,6 @@ lnet_return_tx_credits_locked(struct lnet_msg *msg) } if (txpeer != NULL) { - /* - * TODO: - * Once the patch for the health comes in we need to set - * the health of the peer ni to bad when we fail to send - * a message. - * int status = msg->msg_ev.status; - * if (status != 0) - * lnet_set_peer_ni_health_locked(txpeer, false) - */ msg->msg_txpeer = NULL; lnet_peer_ni_decref_locked(txpeer); } @@ -1226,6 +1185,8 @@ lnet_drop_routed_msgs_locked(struct list_head *list, int cpt) lnet_ni_recv(msg->msg_rxni, msg->msg_private, NULL, 0, 0, 0, msg->msg_hdr.payload_length); list_del_init(&msg->msg_list); + msg->msg_no_resend = true; + msg->msg_health_status = LNET_MSG_STATUS_REMOTE_ERROR; lnet_finalize(msg, -ECANCELED); } @@ -1235,7 +1196,8 @@ lnet_drop_routed_msgs_locked(struct list_head *list, int cpt) void lnet_return_rx_credits_locked(struct lnet_msg *msg) { - struct lnet_peer_ni *rxpeer = msg->msg_rxpeer; + struct lnet_peer_ni *rxpeerni = msg->msg_rxpeer; + struct lnet_peer *lp; struct lnet_ni *rxni = msg->msg_rxni; struct lnet_msg *msg2; @@ -1285,45 +1247,69 @@ lnet_return_rx_credits_locked(struct lnet_msg *msg) routing_off: if (msg->msg_peerrtrcredit) { + LASSERT(rxpeerni); + LASSERT(rxpeerni->lpni_peer_net); + LASSERT(rxpeerni->lpni_peer_net->lpn_peer); + + lp = rxpeerni->lpni_peer_net->lpn_peer; + /* give back peer router credits */ msg->msg_peerrtrcredit = 0; - spin_lock(&rxpeer->lpni_lock); - LASSERT((rxpeer->lpni_rtrcredits < 0) == - !list_empty(&rxpeer->lpni_rtrq)); + spin_lock(&rxpeerni->lpni_lock); + spin_lock(&lp->lp_lock); - rxpeer->lpni_rtrcredits++; + rxpeerni->lpni_rtrcredits++; /* drop all messages which are queued to be routed on that * peer. */ if (!the_lnet.ln_routing) { - struct list_head drop; - INIT_LIST_HEAD(&drop); - list_splice_init(&rxpeer->lpni_rtrq, &drop); - spin_unlock(&rxpeer->lpni_lock); + LIST_HEAD(drop); + list_splice_init(&lp->lp_rtrq, &drop); + spin_unlock(&lp->lp_lock); + spin_unlock(&rxpeerni->lpni_lock); lnet_drop_routed_msgs_locked(&drop, msg->msg_rx_cpt); - } else if (rxpeer->lpni_rtrcredits <= 0) { - msg2 = list_entry(rxpeer->lpni_rtrq.next, + } else if (!list_empty(&lp->lp_rtrq)) { + int msg2_cpt; + + msg2 = list_entry(lp->lp_rtrq.next, struct lnet_msg, msg_list); list_del(&msg2->msg_list); - spin_unlock(&rxpeer->lpni_lock); + msg2_cpt = msg2->msg_rx_cpt; + spin_unlock(&lp->lp_lock); + spin_unlock(&rxpeerni->lpni_lock); + /* + * messages on the lp_rtrq can be from any NID in + * the peer, which means they might have different + * cpts. We need to make sure we lock the right + * one. + */ + if (msg2_cpt != msg->msg_rx_cpt) { + lnet_net_unlock(msg->msg_rx_cpt); + lnet_net_lock(msg2_cpt); + } (void) lnet_post_routed_recv_locked(msg2, 1); + if (msg2_cpt != msg->msg_rx_cpt) { + lnet_net_unlock(msg2_cpt); + lnet_net_lock(msg->msg_rx_cpt); + } } else { - spin_unlock(&rxpeer->lpni_lock); + spin_unlock(&lp->lp_lock); + spin_unlock(&rxpeerni->lpni_lock); } } if (rxni != NULL) { msg->msg_rxni = NULL; lnet_ni_decref_locked(rxni, msg->msg_rx_cpt); } - if (rxpeer != NULL) { + if (rxpeerni != NULL) { msg->msg_rxpeer = NULL; - lnet_peer_ni_decref_locked(rxpeer); + lnet_peer_ni_decref_locked(rxpeerni); } } static int -lnet_compare_peers(struct lnet_peer_ni *p1, struct lnet_peer_ni *p2) +lnet_compare_gw_lpnis(struct lnet_peer_ni *p1, struct lnet_peer_ni *p2) { if (p1->lpni_txqnob < p2->lpni_txqnob) return 1; @@ -1340,14 +1326,133 @@ lnet_compare_peers(struct lnet_peer_ni *p1, struct lnet_peer_ni *p2) return 0; } +static struct lnet_peer_ni * +lnet_select_peer_ni(struct lnet_ni *best_ni, lnet_nid_t dst_nid, + struct lnet_peer *peer, + struct lnet_peer_net *peer_net) +{ + /* + * Look at the peer NIs for the destination peer that connect + * to the chosen net. If a peer_ni is preferred when using the + * best_ni to communicate, we use that one. If there is no + * preferred peer_ni, or there are multiple preferred peer_ni, + * the available transmit credits are used. If the transmit + * credits are equal, we round-robin over the peer_ni. + */ + struct lnet_peer_ni *lpni = NULL; + struct lnet_peer_ni *best_lpni = NULL; + int best_lpni_credits = INT_MIN; + bool preferred = false; + bool ni_is_pref; + int best_lpni_healthv = 0; + int lpni_healthv; + + while ((lpni = lnet_get_next_peer_ni_locked(peer, peer_net, lpni))) { + /* + * if the best_ni we've chosen aleady has this lpni + * preferred, then let's use it + */ + if (best_ni) { + ni_is_pref = lnet_peer_is_pref_nid_locked(lpni, + best_ni->ni_nid); + CDEBUG(D_NET, "%s ni_is_pref = %d\n", + libcfs_nid2str(best_ni->ni_nid), ni_is_pref); + } else { + ni_is_pref = false; + } + + lpni_healthv = atomic_read(&lpni->lpni_healthv); + + if (best_lpni) + CDEBUG(D_NET, "%s c:[%d, %d], s:[%d, %d]\n", + libcfs_nid2str(lpni->lpni_nid), + lpni->lpni_txcredits, best_lpni_credits, + lpni->lpni_seq, best_lpni->lpni_seq); + + /* pick the healthiest peer ni */ + if (lpni_healthv < best_lpni_healthv) { + continue; + } else if (lpni_healthv > best_lpni_healthv) { + best_lpni_healthv = lpni_healthv; + /* if this is a preferred peer use it */ + } else if (!preferred && ni_is_pref) { + preferred = true; + } else if (preferred && !ni_is_pref) { + /* + * this is not the preferred peer so let's ignore + * it. + */ + continue; + } else if (lpni->lpni_txcredits < best_lpni_credits) { + /* + * We already have a peer that has more credits + * available than this one. No need to consider + * this peer further. + */ + continue; + } else if (lpni->lpni_txcredits == best_lpni_credits) { + /* + * The best peer found so far and the current peer + * have the same number of available credits let's + * make sure to select between them using Round + * Robin + */ + if (best_lpni) { + if (best_lpni->lpni_seq <= lpni->lpni_seq) + continue; + } + } + + best_lpni = lpni; + best_lpni_credits = lpni->lpni_txcredits; + } + + /* if we still can't find a peer ni then we can't reach it */ + if (!best_lpni) { + __u32 net_id = (peer_net) ? peer_net->lpn_net_id : + LNET_NIDNET(dst_nid); + CDEBUG(D_NET, "no peer_ni found on peer net %s\n", + libcfs_net2str(net_id)); + return NULL; + } + + CDEBUG(D_NET, "sd_best_lpni = %s\n", + libcfs_nid2str(best_lpni->lpni_nid)); + + return best_lpni; +} + +/* + * Prerequisite: the best_ni should already be set in the sd + */ +static inline struct lnet_peer_ni * +lnet_find_best_lpni_on_net(struct lnet_ni *lni, lnet_nid_t dst_nid, + struct lnet_peer *peer, __u32 net_id) +{ + struct lnet_peer_net *peer_net; + + /* + * The gateway is Multi-Rail capable so now we must select the + * proper peer_ni + */ + peer_net = lnet_peer_get_net_locked(peer, net_id); + + if (!peer_net) { + CERROR("gateway peer %s has no NI on net %s\n", + libcfs_nid2str(peer->lp_primary_nid), + libcfs_net2str(net_id)); + return NULL; + } + + return lnet_select_peer_ni(lni, dst_nid, peer, peer_net); +} + +/* Compare route priorities and hop counts */ static int lnet_compare_routes(struct lnet_route *r1, struct lnet_route *r2) { - struct lnet_peer_ni *p1 = r1->lr_gateway; - struct lnet_peer_ni *p2 = r2->lr_gateway; int r1_hops = (r1->lr_hops == LNET_UNDEFINED_HOPS) ? 1 : r1->lr_hops; int r2_hops = (r2->lr_hops == LNET_UNDEFINED_HOPS) ? 1 : r2->lr_hops; - int rc; if (r1->lr_priority < r2->lr_priority) return 1; @@ -1361,52 +1466,43 @@ lnet_compare_routes(struct lnet_route *r1, struct lnet_route *r2) if (r1_hops > r2_hops) return -1; - rc = lnet_compare_peers(p1, p2); - if (rc) - return rc; - - if (r1->lr_seq - r2->lr_seq <= 0) - return 1; - - return -1; + return 0; } -static struct lnet_peer_ni * -lnet_find_route_locked(struct lnet_net *net, lnet_nid_t target, - lnet_nid_t rtr_nid) -{ - struct lnet_remotenet *rnet; - struct lnet_route *route; - struct lnet_route *best_route; - struct lnet_route *last_route; - struct lnet_peer_ni *lpni_best; - struct lnet_peer_ni *lp; - int rc; - - /* If @rtr_nid is not LNET_NID_ANY, return the gateway with - * rtr_nid nid, otherwise find the best gateway I can use */ - - rnet = lnet_find_rnet_locked(LNET_NIDNET(target)); - if (rnet == NULL) - return NULL; +static struct lnet_route * +lnet_find_route_locked(struct lnet_remotenet *rnet, __u32 src_net, + struct lnet_route **prev_route, + struct lnet_peer_ni **gwni) +{ + struct lnet_peer_ni *lpni, *best_gw_ni = NULL; + struct lnet_route *best_route; + struct lnet_route *last_route; + struct lnet_route *route; + int rc; + __u32 restrict_net; + __u32 any_net = LNET_NIDNET(LNET_NID_ANY); - lpni_best = NULL; best_route = last_route = NULL; list_for_each_entry(route, &rnet->lrn_routes, lr_list) { - lp = route->lr_gateway; - if (!lnet_is_route_alive(route)) continue; - if (net != NULL && lp->lpni_net != net) - continue; - - if (lp->lpni_nid == rtr_nid) /* it's pre-determined router */ - return lp; + /* If the src_net is specified then we need to find an lpni + * on that network + */ + restrict_net = src_net == any_net ? route->lr_lnet : src_net; + if (!best_route) { + lpni = lnet_find_best_lpni_on_net(NULL, LNET_NID_ANY, + route->lr_gateway, + restrict_net); + if (lpni) { + best_route = last_route = route; + best_gw_ni = lpni; + } else + CERROR("Gateway %s does not have a peer NI on net %s\n", + libcfs_nid2str(route->lr_gateway->lp_primary_nid), + libcfs_net2str(restrict_net)); - if (lpni_best == NULL) { - best_route = last_route = route; - lpni_best = lp; continue; } @@ -1415,46 +1511,79 @@ lnet_find_route_locked(struct lnet_net *net, lnet_nid_t target, last_route = route; rc = lnet_compare_routes(route, best_route); - if (rc < 0) + if (rc == -1) + continue; + + lpni = lnet_find_best_lpni_on_net(NULL, LNET_NID_ANY, + route->lr_gateway, + restrict_net); + if (!lpni) { + CERROR("Gateway %s does not have a peer NI on net %s\n", + libcfs_nid2str(route->lr_gateway->lp_primary_nid), + libcfs_net2str(restrict_net)); + continue; + } + + if (rc == 1) { + best_route = route; + best_gw_ni = lpni; + continue; + } + + rc = lnet_compare_gw_lpnis(lpni, best_gw_ni); + if (rc == -1) continue; - best_route = route; - lpni_best = lp; + if (rc == 1 || route->lr_seq <= best_route->lr_seq) { + best_route = route; + best_gw_ni = lpni; + continue; + } } - /* set sequence number on the best router to the latest sequence + 1 - * so we can round-robin all routers, it's race and inaccurate but - * harmless and functional */ - if (best_route != NULL) - best_route->lr_seq = last_route->lr_seq + 1; - return lpni_best; + *prev_route = last_route; + *gwni = best_gw_ni; + + return best_route; } static struct lnet_ni * -lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *cur_ni, +lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni, + struct lnet_peer *peer, struct lnet_peer_net *peer_net, int md_cpt) { - struct lnet_ni *ni = NULL, *best_ni = cur_ni; + struct lnet_ni *ni = NULL; unsigned int shortest_distance; int best_credits; + int best_healthv; + + /* + * If there is no peer_ni that we can send to on this network, + * then there is no point in looking for a new best_ni here. + */ + if (!lnet_get_next_peer_ni_locked(peer, peer_net, NULL)) + return best_ni; if (best_ni == NULL) { shortest_distance = UINT_MAX; best_credits = INT_MIN; + best_healthv = 0; } else { shortest_distance = cfs_cpt_distance(lnet_cpt_table(), md_cpt, best_ni->ni_dev_cpt); best_credits = atomic_read(&best_ni->ni_tx_credits); + best_healthv = atomic_read(&best_ni->ni_healthv); } while ((ni = lnet_get_next_ni_locked(local_net, ni))) { unsigned int distance; int ni_credits; - - if (!lnet_is_ni_healthy_locked(ni)) - continue; + int ni_healthv; + int ni_fatal; ni_credits = atomic_read(&ni->ni_tx_credits); + ni_healthv = atomic_read(&ni->ni_healthv); + ni_fatal = atomic_read(&ni->ni_fatal_error_on); /* * calculate the distance from the CPT on which @@ -1465,6 +1594,12 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *cur_ni, md_cpt, ni->ni_dev_cpt); + CDEBUG(D_NET, "compare ni %s [c:%d, d:%d, s:%d] with best_ni %s [c:%d, d:%d, s:%d]\n", + libcfs_nid2str(ni->ni_nid), ni_credits, distance, + ni->ni_seq, (best_ni) ? libcfs_nid2str(best_ni->ni_nid) + : "not seleced", best_credits, shortest_distance, + (best_ni) ? best_ni->ni_seq : 0); + /* * All distances smaller than the NUMA range * are treated equally. @@ -1473,23 +1608,41 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *cur_ni, distance = lnet_numa_range; /* - * Select on shorter distance, then available + * Select on health, shorter distance, available * credits, then round-robin. */ - if (distance > shortest_distance) { + if (ni_fatal) { + continue; + } else if (ni_healthv < best_healthv) { + continue; + } else if (ni_healthv > best_healthv) { + best_healthv = ni_healthv; + /* + * If we're going to prefer this ni because it's + * the healthiest, then we should set the + * shortest_distance in the algorithm in case + * there are multiple NIs with the same health but + * different distances. + */ + if (distance < shortest_distance) + shortest_distance = distance; + } else if (distance > shortest_distance) { continue; } else if (distance < shortest_distance) { shortest_distance = distance; } else if (ni_credits < best_credits) { continue; } else if (ni_credits == best_credits) { - if (best_ni && (best_ni)->ni_seq <= ni->ni_seq) + if (best_ni && best_ni->ni_seq <= ni->ni_seq) continue; } best_ni = ni; best_credits = ni_credits; } + CDEBUG(D_NET, "selected best_ni %s\n", + (best_ni) ? libcfs_nid2str(best_ni->ni_nid) : "no selection"); + return best_ni; } @@ -1514,643 +1667,2163 @@ lnet_msg_discovery(struct lnet_msg *msg) return false; } +#define SRC_SPEC 0x0001 +#define SRC_ANY 0x0002 +#define LOCAL_DST 0x0004 +#define REMOTE_DST 0x0008 +#define MR_DST 0x0010 +#define NMR_DST 0x0020 +#define SND_RESP 0x0040 + +/* The following to defines are used for return codes */ +#define REPEAT_SEND 0x1000 +#define PASS_THROUGH 0x2000 + +/* The different cases lnet_select pathway needs to handle */ +#define SRC_SPEC_LOCAL_MR_DST (SRC_SPEC | LOCAL_DST | MR_DST) +#define SRC_SPEC_ROUTER_MR_DST (SRC_SPEC | REMOTE_DST | MR_DST) +#define SRC_SPEC_LOCAL_NMR_DST (SRC_SPEC | LOCAL_DST | NMR_DST) +#define SRC_SPEC_ROUTER_NMR_DST (SRC_SPEC | REMOTE_DST | NMR_DST) +#define SRC_ANY_LOCAL_MR_DST (SRC_ANY | LOCAL_DST | MR_DST) +#define SRC_ANY_ROUTER_MR_DST (SRC_ANY | REMOTE_DST | MR_DST) +#define SRC_ANY_LOCAL_NMR_DST (SRC_ANY | LOCAL_DST | NMR_DST) +#define SRC_ANY_ROUTER_NMR_DST (SRC_ANY | REMOTE_DST | NMR_DST) + static int -lnet_select_pathway(lnet_nid_t src_nid, lnet_nid_t dst_nid, - struct lnet_msg *msg, lnet_nid_t rtr_nid) +lnet_handle_lo_send(struct lnet_send_data *sd) { - struct lnet_ni *best_ni; - struct lnet_peer_ni *best_lpni; - struct lnet_peer_ni *best_gw; - struct lnet_peer_ni *lpni; - struct lnet_peer_ni *final_dst; - struct lnet_peer *peer; - struct lnet_peer_net *peer_net; - struct lnet_net *local_net; - int cpt, cpt2, rc; - bool routing; - bool routing2; - bool ni_is_pref; - bool preferred; - bool local_found; - int best_lpni_credits; - int md_cpt; + struct lnet_msg *msg = sd->sd_msg; + int cpt = sd->sd_cpt; - /* - * get an initial CPT to use for locking. The idea here is not to - * serialize the calls to select_pathway, so that as many - * operations can run concurrently as possible. To do that we use - * the CPT where this call is being executed. Later on when we - * determine the CPT to use in lnet_message_commit, we switch the - * lock and check if there was any configuration change. If none, - * then we proceed, if there is, then we restart the operation. - */ - cpt = lnet_net_lock_current(); + /* No send credit hassles with LOLND */ + lnet_ni_addref_locked(the_lnet.ln_loni, cpt); + msg->msg_hdr.dest_nid = cpu_to_le64(the_lnet.ln_loni->ni_nid); + if (!msg->msg_routing) + msg->msg_hdr.src_nid = + cpu_to_le64(the_lnet.ln_loni->ni_nid); + msg->msg_target.nid = the_lnet.ln_loni->ni_nid; + lnet_msg_commit(msg, cpt); + msg->msg_txni = the_lnet.ln_loni; - md_cpt = lnet_cpt_of_md(msg->msg_md, msg->msg_offset); - if (md_cpt == CFS_CPT_ANY) - md_cpt = cpt; + return LNET_CREDIT_OK; +} -again: - best_ni = NULL; - best_lpni = NULL; - best_gw = NULL; - final_dst = NULL; - local_net = NULL; - routing = false; - routing2 = false; - local_found = false; +static int +lnet_handle_send(struct lnet_send_data *sd) +{ + struct lnet_ni *best_ni = sd->sd_best_ni; + struct lnet_peer_ni *best_lpni = sd->sd_best_lpni; + struct lnet_peer_ni *final_dst_lpni = sd->sd_final_dst_lpni; + struct lnet_msg *msg = sd->sd_msg; + int cpt2; + __u32 send_case = sd->sd_send_case; + int rc; + __u32 routing = send_case & REMOTE_DST; + struct lnet_rsp_tracker *rspt; /* - * lnet_nid2peerni_locked() is the path that will find an - * existing peer_ni, or create one and mark it as having been - * created due to network traffic. + * Increment sequence number of the selected peer so that we + * pick the next one in Round Robin. */ - lpni = lnet_nid2peerni_locked(dst_nid, LNET_NID_ANY, cpt); - if (IS_ERR(lpni)) { - lnet_net_unlock(cpt); - return PTR_ERR(lpni); - } + best_lpni->lpni_seq++; /* - * If we're being asked to send to the loopback interface, there - * is no need to go through any selection. We can just shortcut - * the entire process and send over lolnd + * grab a reference on the peer_ni so it sticks around even if + * we need to drop and relock the lnet_net_lock below. */ - if (LNET_NETTYP(LNET_NIDNET(dst_nid)) == LOLND) { - lnet_peer_ni_decref_locked(lpni); - best_ni = the_lnet.ln_loni; - goto send; - } + lnet_peer_ni_addref_locked(best_lpni); /* - * Now that we have a peer_ni, check if we want to discover - * the peer. Traffic to the LNET_RESERVED_PORTAL should not - * trigger discovery. + * Use lnet_cpt_of_nid() to determine the CPT used to commit the + * message. This ensures that we get a CPT that is correct for + * the NI when the NI has been restricted to a subset of all CPTs. + * If the selected CPT differs from the one currently locked, we + * must unlock and relock the lnet_net_lock(), and then check whether + * the configuration has changed. We don't have a hold on the best_ni + * yet, and it may have vanished. */ - peer = lpni->lpni_peer_net->lpn_peer; - if (lnet_msg_discovery(msg) && !lnet_peer_is_uptodate(peer)) { - rc = lnet_discover_peer_locked(lpni, cpt, false); - if (rc) { - lnet_peer_ni_decref_locked(lpni); - lnet_net_unlock(cpt); - return rc; + cpt2 = lnet_cpt_of_nid_locked(best_lpni->lpni_nid, best_ni); + if (sd->sd_cpt != cpt2) { + __u32 seq = lnet_get_dlc_seq_locked(); + lnet_net_unlock(sd->sd_cpt); + sd->sd_cpt = cpt2; + lnet_net_lock(sd->sd_cpt); + if (seq != lnet_get_dlc_seq_locked()) { + lnet_peer_ni_decref_locked(best_lpni); + return REPEAT_SEND; } - /* The peer may have changed. */ - peer = lpni->lpni_peer_net->lpn_peer; - /* queue message and return */ - msg->msg_src_nid_param = src_nid; - msg->msg_rtr_nid_param = rtr_nid; - msg->msg_sending = 0; - list_add_tail(&msg->msg_list, &peer->lp_dc_pendq); - lnet_peer_ni_decref_locked(lpni); - lnet_net_unlock(cpt); - - CDEBUG(D_NET, "%s pending discovery\n", - libcfs_nid2str(peer->lp_primary_nid)); - - return LNET_DC_WAIT; - } - lnet_peer_ni_decref_locked(lpni); - - /* If peer is not healthy then can not send anything to it */ - if (!lnet_is_peer_healthy_locked(peer)) { - lnet_net_unlock(cpt); - return -EHOSTUNREACH; } /* - * STEP 1: first jab at determining best_ni - * if src_nid is explicitly specified, then best_ni is already - * pre-determiend for us. Otherwise we need to select the best - * one to use later on + * store the best_lpni in the message right away to avoid having + * to do the same operation under different conditions */ - if (src_nid != LNET_NID_ANY) { - best_ni = lnet_nid2ni_locked(src_nid, cpt); - if (!best_ni) { - lnet_net_unlock(cpt); - LCONSOLE_WARN("Can't send to %s: src %s is not a " - "local nid\n", libcfs_nid2str(dst_nid), - libcfs_nid2str(src_nid)); - return -EINVAL; + msg->msg_txpeer = best_lpni; + msg->msg_txni = best_ni; + + /* + * grab a reference for the best_ni since now it's in use in this + * send. The reference will be dropped in lnet_finalize() + */ + lnet_ni_addref_locked(msg->msg_txni, sd->sd_cpt); + + /* + * Always set the target.nid to the best peer picked. Either the + * NID will be one of the peer NIDs selected, or the same NID as + * what was originally set in the target or it will be the NID of + * a router if this message should be routed + */ + msg->msg_target.nid = msg->msg_txpeer->lpni_nid; + + /* + * lnet_msg_commit assigns the correct cpt to the message, which + * is used to decrement the correct refcount on the ni when it's + * time to return the credits + */ + lnet_msg_commit(msg, sd->sd_cpt); + + /* + * If we are routing the message then we keep the src_nid that was + * set by the originator. If we are not routing then we are the + * originator and set it here. + */ + if (!msg->msg_routing) + msg->msg_hdr.src_nid = cpu_to_le64(msg->msg_txni->ni_nid); + + if (routing) { + msg->msg_target_is_router = 1; + msg->msg_target.pid = LNET_PID_LUSTRE; + /* + * since we're routing we want to ensure that the + * msg_hdr.dest_nid is set to the final destination. When + * the router receives this message it knows how to route + * it. + * + * final_dst_lpni is set at the beginning of the + * lnet_select_pathway() function and is never changed. + * It's safe to use it here. + */ + msg->msg_hdr.dest_nid = cpu_to_le64(final_dst_lpni->lpni_nid); + } else { + /* + * if we're not routing set the dest_nid to the best peer + * ni NID that we picked earlier in the algorithm. + */ + msg->msg_hdr.dest_nid = cpu_to_le64(msg->msg_txpeer->lpni_nid); + } + + /* + * if we have response tracker block update it with the next hop + * nid + */ + if (msg->msg_md) { + rspt = msg->msg_md->md_rspt_ptr; + if (rspt) { + rspt->rspt_next_hop_nid = msg->msg_txpeer->lpni_nid; + CDEBUG(D_NET, "rspt_next_hop_nid = %s\n", + libcfs_nid2str(rspt->rspt_next_hop_nid)); + } + } + + rc = lnet_post_send_locked(msg, 0); + + if (!rc) + CDEBUG(D_NET, "TRACE: %s(%s:%s) -> %s(%s:%s) %s : %s try# %d\n", + libcfs_nid2str(msg->msg_hdr.src_nid), + libcfs_nid2str(msg->msg_txni->ni_nid), + libcfs_nid2str(sd->sd_src_nid), + libcfs_nid2str(msg->msg_hdr.dest_nid), + libcfs_nid2str(sd->sd_dst_nid), + libcfs_nid2str(msg->msg_txpeer->lpni_nid), + libcfs_nid2str(sd->sd_rtr_nid), + lnet_msgtyp2str(msg->msg_type), msg->msg_retry_count); + + return rc; +} + +static inline void +lnet_set_non_mr_pref_nid(struct lnet_send_data *sd) +{ + if (sd->sd_send_case & NMR_DST && + sd->sd_msg->msg_type != LNET_MSG_REPLY && + sd->sd_msg->msg_type != LNET_MSG_ACK && + sd->sd_best_lpni->lpni_pref_nnids == 0) { + CDEBUG(D_NET, "Setting preferred local NID %s on NMR peer %s\n", + libcfs_nid2str(sd->sd_best_ni->ni_nid), + libcfs_nid2str(sd->sd_best_lpni->lpni_nid)); + lnet_peer_ni_set_non_mr_pref_nid(sd->sd_best_lpni, + sd->sd_best_ni->ni_nid); + } +} + +/* + * Source Specified + * Local Destination + * non-mr peer + * + * use the source and destination NIDs as the pathway + */ +static int +lnet_handle_spec_local_nmr_dst(struct lnet_send_data *sd) +{ + /* the destination lpni is set before we get here. */ + + /* find local NI */ + sd->sd_best_ni = lnet_nid2ni_locked(sd->sd_src_nid, sd->sd_cpt); + if (!sd->sd_best_ni) { + CERROR("Can't send to %s: src %s is not a " + "local nid\n", libcfs_nid2str(sd->sd_dst_nid), + libcfs_nid2str(sd->sd_src_nid)); + return -EINVAL; + } + + /* + * the preferred NID will only be set for NMR peers + */ + lnet_set_non_mr_pref_nid(sd); + + return lnet_handle_send(sd); +} + +/* + * Source Specified + * Local Destination + * MR Peer + * + * Don't run the selection algorithm on the peer NIs. By specifying the + * local NID, we're also saying that we should always use the destination NID + * provided. This handles the case where we should be using the same + * destination NID for the all the messages which belong to the same RPC + * request. + */ +static int +lnet_handle_spec_local_mr_dst(struct lnet_send_data *sd) +{ + sd->sd_best_ni = lnet_nid2ni_locked(sd->sd_src_nid, sd->sd_cpt); + if (!sd->sd_best_ni) { + CERROR("Can't send to %s: src %s is not a " + "local nid\n", libcfs_nid2str(sd->sd_dst_nid), + libcfs_nid2str(sd->sd_src_nid)); + return -EINVAL; + } + + if (sd->sd_best_lpni && + sd->sd_best_lpni->lpni_nid == the_lnet.ln_loni->ni_nid) + return lnet_handle_lo_send(sd); + else if (sd->sd_best_lpni) + return lnet_handle_send(sd); + + CERROR("can't send to %s. no NI on %s\n", + libcfs_nid2str(sd->sd_dst_nid), + libcfs_net2str(sd->sd_best_ni->ni_net->net_id)); + + return -EHOSTUNREACH; +} + +struct lnet_ni * +lnet_find_best_ni_on_spec_net(struct lnet_ni *cur_best_ni, + struct lnet_peer *peer, + struct lnet_peer_net *peer_net, + int cpt, + bool incr_seq) +{ + struct lnet_net *local_net; + struct lnet_ni *best_ni; + + local_net = lnet_get_net_locked(peer_net->lpn_net_id); + if (!local_net) + return NULL; + + /* + * Iterate through the NIs in this local Net and select + * the NI to send from. The selection is determined by + * these 3 criterion in the following priority: + * 1. NUMA + * 2. NI available credits + * 3. Round Robin + */ + best_ni = lnet_get_best_ni(local_net, cur_best_ni, + peer, peer_net, cpt); + + if (incr_seq && best_ni) + best_ni->ni_seq++; + + return best_ni; +} + +static int +lnet_initiate_peer_discovery(struct lnet_peer_ni *lpni, + struct lnet_msg *msg, lnet_nid_t rtr_nid, + int cpt) +{ + struct lnet_peer *peer; + lnet_nid_t primary_nid; + int rc; + + lnet_peer_ni_addref_locked(lpni); + + peer = lpni->lpni_peer_net->lpn_peer; + + if (lnet_peer_gw_discovery(peer)) { + lnet_peer_ni_decref_locked(lpni); + return 0; + } + + if (!lnet_msg_discovery(msg) || lnet_peer_is_uptodate(peer)) { + lnet_peer_ni_decref_locked(lpni); + return 0; + } + + rc = lnet_discover_peer_locked(lpni, cpt, false); + if (rc) { + lnet_peer_ni_decref_locked(lpni); + return rc; + } + /* The peer may have changed. */ + peer = lpni->lpni_peer_net->lpn_peer; + spin_lock(&peer->lp_lock); + if (lnet_peer_is_uptodate_locked(peer)) { + spin_unlock(&peer->lp_lock); + lnet_peer_ni_decref_locked(lpni); + return 0; + } + /* queue message and return */ + msg->msg_rtr_nid_param = rtr_nid; + msg->msg_sending = 0; + msg->msg_txpeer = NULL; + list_add_tail(&msg->msg_list, &peer->lp_dc_pendq); + primary_nid = peer->lp_primary_nid; + spin_unlock(&peer->lp_lock); + + lnet_peer_ni_decref_locked(lpni); + + CDEBUG(D_NET, "msg %p delayed. %s pending discovery\n", + msg, libcfs_nid2str(primary_nid)); + + return LNET_DC_WAIT; +} + +static int +lnet_handle_find_routed_path(struct lnet_send_data *sd, + lnet_nid_t dst_nid, + struct lnet_peer_ni **gw_lpni, + struct lnet_peer **gw_peer) +{ + int rc; + __u32 local_lnet; + struct lnet_peer *gw; + struct lnet_peer *lp; + struct lnet_peer_net *lpn; + struct lnet_peer_net *best_lpn = NULL; + struct lnet_remotenet *rnet, *best_rnet = NULL; + struct lnet_route *best_route = NULL; + struct lnet_route *last_route = NULL; + struct lnet_peer_ni *lpni = NULL; + struct lnet_peer_ni *gwni = NULL; + lnet_nid_t src_nid = sd->sd_src_nid; + + /* If a router nid was specified then we are replying to a GET or + * sending an ACK. In this case we use the gateway associated with the + * specified router nid. + */ + if (sd->sd_rtr_nid != LNET_NID_ANY) { + gwni = lnet_find_peer_ni_locked(sd->sd_rtr_nid); + if (!gwni) { + CERROR("No peer NI for gateway %s\n", + libcfs_nid2str(sd->sd_rtr_nid)); + return -EHOSTUNREACH; + } + gw = gwni->lpni_peer_net->lpn_peer; + lnet_peer_ni_decref_locked(gwni); + local_lnet = LNET_NIDNET(sd->sd_rtr_nid); + } else { + /* we've already looked up the initial lpni using dst_nid */ + lpni = sd->sd_best_lpni; + /* the peer tree must be in existence */ + LASSERT(lpni && lpni->lpni_peer_net && + lpni->lpni_peer_net->lpn_peer); + lp = lpni->lpni_peer_net->lpn_peer; + + list_for_each_entry(lpn, &lp->lp_peer_nets, lpn_peer_nets) { + /* is this remote network reachable? */ + rnet = lnet_find_rnet_locked(lpn->lpn_net_id); + if (!rnet) + continue; + + if (!best_lpn) { + best_lpn = lpn; + best_rnet = rnet; + } + + if (best_lpn->lpn_seq <= lpn->lpn_seq) + continue; + + best_lpn = lpn; + best_rnet = rnet; + } + + if (!best_lpn) { + CERROR("peer %s has no available nets\n", + libcfs_nid2str(sd->sd_dst_nid)); + return -EHOSTUNREACH; + } + + sd->sd_best_lpni = lnet_find_best_lpni_on_net(sd->sd_best_ni, + sd->sd_dst_nid, + lp, + best_lpn->lpn_net_id); + if (!sd->sd_best_lpni) { + CERROR("peer %s down\n", + libcfs_nid2str(sd->sd_dst_nid)); + return -EHOSTUNREACH; + } + + best_route = lnet_find_route_locked(best_rnet, + LNET_NIDNET(src_nid), + &last_route, &gwni); + if (!best_route) { + CERROR("no route to %s from %s\n", + libcfs_nid2str(dst_nid), + libcfs_nid2str(src_nid)); + return -EHOSTUNREACH; + } + + if (!gwni) { + CERROR("Internal Error. Route expected to %s from %s\n", + libcfs_nid2str(dst_nid), + libcfs_nid2str(src_nid)); + return -EFAULT; + } + + gw = best_route->lr_gateway; + LASSERT(gw == gwni->lpni_peer_net->lpn_peer); + local_lnet = best_route->lr_lnet; + + } + + /* + * Discover this gateway if it hasn't already been discovered. + * This means we might delay the message until discovery has + * completed + */ + sd->sd_msg->msg_src_nid_param = sd->sd_src_nid; + rc = lnet_initiate_peer_discovery(gwni, sd->sd_msg, sd->sd_rtr_nid, + sd->sd_cpt); + if (rc) + return rc; + + if (!sd->sd_best_ni) + sd->sd_best_ni = lnet_find_best_ni_on_spec_net(NULL, gw, + lnet_peer_get_net_locked(gw, + local_lnet), + sd->sd_md_cpt, + true); + + if (!sd->sd_best_ni) { + CERROR("Internal Error. Expected local ni on %s but non found :%s\n", + libcfs_net2str(local_lnet), + libcfs_nid2str(sd->sd_src_nid)); + return -EFAULT; + } + + *gw_lpni = gwni; + *gw_peer = gw; + + /* + * increment the sequence numbers since now we're sure we're + * going to use this path + */ + if (sd->sd_rtr_nid == LNET_NID_ANY) { + LASSERT(best_route && last_route); + best_route->lr_seq = last_route->lr_seq + 1; + best_lpn->lpn_seq++; + } + + return 0; +} + +/* + * Handle two cases: + * + * Case 1: + * Source specified + * Remote destination + * Non-MR destination + * + * Case 2: + * Source specified + * Remote destination + * MR destination + * + * The handling of these two cases is similar. Even though the destination + * can be MR or non-MR, we'll deal directly with the router. + */ +static int +lnet_handle_spec_router_dst(struct lnet_send_data *sd) +{ + int rc; + struct lnet_peer_ni *gw_lpni = NULL; + struct lnet_peer *gw_peer = NULL; + + /* find local NI */ + sd->sd_best_ni = lnet_nid2ni_locked(sd->sd_src_nid, sd->sd_cpt); + if (!sd->sd_best_ni) { + CERROR("Can't send to %s: src %s is not a " + "local nid\n", libcfs_nid2str(sd->sd_dst_nid), + libcfs_nid2str(sd->sd_src_nid)); + return -EINVAL; + } + + rc = lnet_handle_find_routed_path(sd, sd->sd_dst_nid, &gw_lpni, + &gw_peer); + if (rc) + return rc; + + if (sd->sd_send_case & NMR_DST) + /* + * since the final destination is non-MR let's set its preferred + * NID before we send + */ + lnet_set_non_mr_pref_nid(sd); + + /* + * We're going to send to the gw found so let's set its + * info + */ + sd->sd_peer = gw_peer; + sd->sd_best_lpni = gw_lpni; + + return lnet_handle_send(sd); +} + +struct lnet_ni * +lnet_find_best_ni_on_local_net(struct lnet_peer *peer, int md_cpt, + bool discovery) +{ + struct lnet_peer_net *peer_net = NULL; + struct lnet_ni *best_ni = NULL; + + /* + * The peer can have multiple interfaces, some of them can be on + * the local network and others on a routed network. We should + * prefer the local network. However if the local network is not + * available then we need to try the routed network + */ + + /* go through all the peer nets and find the best_ni */ + list_for_each_entry(peer_net, &peer->lp_peer_nets, lpn_peer_nets) { + /* + * The peer's list of nets can contain non-local nets. We + * want to only examine the local ones. + */ + if (!lnet_get_net_locked(peer_net->lpn_net_id)) + continue; + best_ni = lnet_find_best_ni_on_spec_net(best_ni, peer, + peer_net, md_cpt, false); + + /* + * if this is a discovery message and lp_disc_net_id is + * specified then use that net to send the discovery on. + */ + if (peer->lp_disc_net_id == peer_net->lpn_net_id && + discovery) + break; + } + + if (best_ni) + /* increment sequence number so we can round robin */ + best_ni->ni_seq++; + + return best_ni; +} + +static struct lnet_ni * +lnet_find_existing_preferred_best_ni(struct lnet_send_data *sd) +{ + struct lnet_ni *best_ni = NULL; + struct lnet_peer_net *peer_net; + struct lnet_peer *peer = sd->sd_peer; + struct lnet_peer_ni *best_lpni = sd->sd_best_lpni; + struct lnet_peer_ni *lpni; + int cpt = sd->sd_cpt; + + /* + * We must use a consistent source address when sending to a + * non-MR peer. However, a non-MR peer can have multiple NIDs + * on multiple networks, and we may even need to talk to this + * peer on multiple networks -- certain types of + * load-balancing configuration do this. + * + * So we need to pick the NI the peer prefers for this + * particular network. + */ + + /* Get the target peer_ni */ + peer_net = lnet_peer_get_net_locked(peer, + LNET_NIDNET(best_lpni->lpni_nid)); + LASSERT(peer_net != NULL); + list_for_each_entry(lpni, &peer_net->lpn_peer_nis, + lpni_peer_nis) { + if (lpni->lpni_pref_nnids == 0) + continue; + LASSERT(lpni->lpni_pref_nnids == 1); + best_ni = lnet_nid2ni_locked( + lpni->lpni_pref.nid, cpt); + break; + } + + return best_ni; +} + +/* Prerequisite: sd->sd_peer and sd->sd_best_lpni should be set */ +static int +lnet_select_preferred_best_ni(struct lnet_send_data *sd) +{ + struct lnet_ni *best_ni = NULL; + struct lnet_peer_ni *best_lpni = sd->sd_best_lpni; + + /* + * We must use a consistent source address when sending to a + * non-MR peer. However, a non-MR peer can have multiple NIDs + * on multiple networks, and we may even need to talk to this + * peer on multiple networks -- certain types of + * load-balancing configuration do this. + * + * So we need to pick the NI the peer prefers for this + * particular network. + */ + + best_ni = lnet_find_existing_preferred_best_ni(sd); + + /* if best_ni is still not set just pick one */ + if (!best_ni) { + best_ni = + lnet_find_best_ni_on_spec_net(NULL, sd->sd_peer, + sd->sd_best_lpni->lpni_peer_net, + sd->sd_md_cpt, true); + /* If there is no best_ni we don't have a route */ + if (!best_ni) { + CERROR("no path to %s from net %s\n", + libcfs_nid2str(best_lpni->lpni_nid), + libcfs_net2str(best_lpni->lpni_net->net_id)); + return -EHOSTUNREACH; + } + } + + sd->sd_best_ni = best_ni; + + /* Set preferred NI if necessary. */ + lnet_set_non_mr_pref_nid(sd); + + return 0; +} + + +/* + * Source not specified + * Local destination + * Non-MR Peer + * + * always use the same source NID for NMR peers + * If we've talked to that peer before then we already have a preferred + * source NI associated with it. Otherwise, we select a preferred local NI + * and store it in the peer + */ +static int +lnet_handle_any_local_nmr_dst(struct lnet_send_data *sd) +{ + int rc; + + /* sd->sd_best_lpni is already set to the final destination */ + + /* + * At this point we should've created the peer ni and peer. If we + * can't find it, then something went wrong. Instead of assert + * output a relevant message and fail the send + */ + if (!sd->sd_best_lpni) { + CERROR("Internal fault. Unable to send msg %s to %s. " + "NID not known\n", + lnet_msgtyp2str(sd->sd_msg->msg_type), + libcfs_nid2str(sd->sd_dst_nid)); + return -EFAULT; + } + + rc = lnet_select_preferred_best_ni(sd); + if (!rc) + rc = lnet_handle_send(sd); + + return rc; +} + +static int +lnet_handle_any_mr_dsta(struct lnet_send_data *sd) +{ + /* + * NOTE we've already handled the remote peer case. So we only + * need to worry about the local case here. + * + * if we're sending a response, ACK or reply, we need to send it + * to the destination NID given to us. At this point we already + * have the peer_ni we're suppose to send to, so just find the + * best_ni on the peer net and use that. Since we're sending to an + * MR peer then we can just run the selection algorithm on our + * local NIs and pick the best one. + */ + if (sd->sd_send_case & SND_RESP) { + sd->sd_best_ni = + lnet_find_best_ni_on_spec_net(NULL, sd->sd_peer, + sd->sd_best_lpni->lpni_peer_net, + sd->sd_md_cpt, true); + + if (!sd->sd_best_ni) { + /* + * We're not going to deal with not able to send + * a response to the provided final destination + */ + CERROR("Can't send response to %s. " + "No local NI available\n", + libcfs_nid2str(sd->sd_dst_nid)); + return -EHOSTUNREACH; + } + + return lnet_handle_send(sd); + } + + /* + * If we get here that means we're sending a fresh request, PUT or + * GET, so we need to run our standard selection algorithm. + * First find the best local interface that's on any of the peer's + * networks. + */ + sd->sd_best_ni = lnet_find_best_ni_on_local_net(sd->sd_peer, + sd->sd_md_cpt, + lnet_msg_discovery(sd->sd_msg)); + if (sd->sd_best_ni) { + sd->sd_best_lpni = + lnet_find_best_lpni_on_net(sd->sd_best_ni, sd->sd_dst_nid, + sd->sd_peer, + sd->sd_best_ni->ni_net->net_id); + + /* + * if we're successful in selecting a peer_ni on the local + * network, then send to it. Otherwise fall through and + * try and see if we can reach it over another routed + * network + */ + if (sd->sd_best_lpni && + sd->sd_best_lpni->lpni_nid == the_lnet.ln_loni->ni_nid) { + /* + * in case we initially started with a routed + * destination, let's reset to local + */ + sd->sd_send_case &= ~REMOTE_DST; + sd->sd_send_case |= LOCAL_DST; + return lnet_handle_lo_send(sd); + } else if (sd->sd_best_lpni) { + /* + * in case we initially started with a routed + * destination, let's reset to local + */ + sd->sd_send_case &= ~REMOTE_DST; + sd->sd_send_case |= LOCAL_DST; + return lnet_handle_send(sd); + } + + CERROR("Internal Error. Expected to have a best_lpni: " + "%s -> %s\n", + libcfs_nid2str(sd->sd_src_nid), + libcfs_nid2str(sd->sd_dst_nid)); + + return -EFAULT; + } + + /* + * Peer doesn't have a local network. Let's see if there is + * a remote network we can reach it on. + */ + return PASS_THROUGH; +} + +/* + * Case 1: + * Source NID not specified + * Local destination + * MR peer + * + * Case 2: + * Source NID not speified + * Remote destination + * MR peer + * + * In both of these cases if we're sending a response, ACK or REPLY, then + * we need to send to the destination NID provided. + * + * In the remote case let's deal with MR routers. + * + */ + +static int +lnet_handle_any_mr_dst(struct lnet_send_data *sd) +{ + int rc = 0; + struct lnet_peer *gw_peer = NULL; + struct lnet_peer_ni *gw_lpni = NULL; + + /* + * handle sending a response to a remote peer here so we don't + * have to worry about it if we hit lnet_handle_any_mr_dsta() + */ + if (sd->sd_send_case & REMOTE_DST && + sd->sd_send_case & SND_RESP) { + struct lnet_peer_ni *gw; + struct lnet_peer *gw_peer; + + rc = lnet_handle_find_routed_path(sd, sd->sd_dst_nid, &gw, + &gw_peer); + if (rc < 0) { + CERROR("Can't send response to %s. " + "No route available\n", + libcfs_nid2str(sd->sd_dst_nid)); + return -EHOSTUNREACH; + } else if (rc > 0) { + return rc; } + + sd->sd_best_lpni = gw; + sd->sd_peer = gw_peer; + + return lnet_handle_send(sd); + } + + /* + * Even though the NID for the peer might not be on a local network, + * since the peer is MR there could be other interfaces on the + * local network. In that case we'd still like to prefer the local + * network over the routed network. If we're unable to do that + * then we select the best router among the different routed networks, + * and if the router is MR then we can deal with it as such. + */ + rc = lnet_handle_any_mr_dsta(sd); + if (rc != PASS_THROUGH) + return rc; + + /* + * Now that we must route to the destination, we must consider the + * MR case, where the destination has multiple interfaces, some of + * which we can route to and others we do not. For this reason we + * need to select the destination which we can route to and if + * there are multiple, we need to round robin. + */ + rc = lnet_handle_find_routed_path(sd, sd->sd_dst_nid, &gw_lpni, + &gw_peer); + if (rc) + return rc; + + sd->sd_send_case &= ~LOCAL_DST; + sd->sd_send_case |= REMOTE_DST; + + sd->sd_peer = gw_peer; + sd->sd_best_lpni = gw_lpni; + + return lnet_handle_send(sd); +} + +/* + * Source not specified + * Remote destination + * Non-MR peer + * + * Must send to the specified peer NID using the same source NID that + * we've used before. If it's the first time to talk to that peer then + * find the source NI and assign it as preferred to that peer + */ +static int +lnet_handle_any_router_nmr_dst(struct lnet_send_data *sd) +{ + int rc; + struct lnet_peer_ni *gw_lpni = NULL; + struct lnet_peer *gw_peer = NULL; + + /* + * Let's set if we have a preferred NI to talk to this NMR peer + */ + sd->sd_best_ni = lnet_find_existing_preferred_best_ni(sd); + + /* + * find the router and that'll find the best NI if we didn't find + * it already. + */ + rc = lnet_handle_find_routed_path(sd, sd->sd_dst_nid, &gw_lpni, + &gw_peer); + if (rc) + return rc; + + /* + * set the best_ni we've chosen as the preferred one for + * this peer + */ + lnet_set_non_mr_pref_nid(sd); + + /* we'll be sending to the gw */ + sd->sd_best_lpni = gw_lpni; + sd->sd_peer = gw_peer; + + return lnet_handle_send(sd); +} + +static int +lnet_handle_send_case_locked(struct lnet_send_data *sd) +{ + /* + * turn off the SND_RESP bit. + * It will be checked in the case handling + */ + __u32 send_case = sd->sd_send_case &= ~SND_RESP ; + + CDEBUG(D_NET, "Source %s%s to %s %s %s destination\n", + (send_case & SRC_SPEC) ? "Specified: " : "ANY", + (send_case & SRC_SPEC) ? libcfs_nid2str(sd->sd_src_nid) : "", + (send_case & MR_DST) ? "MR: " : "NMR: ", + libcfs_nid2str(sd->sd_dst_nid), + (send_case & LOCAL_DST) ? "local" : "routed"); + + switch (send_case) { + /* + * For all cases where the source is specified, we should always + * use the destination NID, whether it's an MR destination or not, + * since we're continuing a series of related messages for the + * same RPC + */ + case SRC_SPEC_LOCAL_NMR_DST: + return lnet_handle_spec_local_nmr_dst(sd); + case SRC_SPEC_LOCAL_MR_DST: + return lnet_handle_spec_local_mr_dst(sd); + case SRC_SPEC_ROUTER_NMR_DST: + case SRC_SPEC_ROUTER_MR_DST: + return lnet_handle_spec_router_dst(sd); + case SRC_ANY_LOCAL_NMR_DST: + return lnet_handle_any_local_nmr_dst(sd); + case SRC_ANY_LOCAL_MR_DST: + case SRC_ANY_ROUTER_MR_DST: + return lnet_handle_any_mr_dst(sd); + case SRC_ANY_ROUTER_NMR_DST: + return lnet_handle_any_router_nmr_dst(sd); + default: + CERROR("Unknown send case\n"); + return -1; + } +} + +static int +lnet_select_pathway(lnet_nid_t src_nid, lnet_nid_t dst_nid, + struct lnet_msg *msg, lnet_nid_t rtr_nid) +{ + struct lnet_peer_ni *lpni; + struct lnet_peer *peer; + struct lnet_send_data send_data; + int cpt, rc; + int md_cpt; + __u32 send_case = 0; + + memset(&send_data, 0, sizeof(send_data)); + + /* + * get an initial CPT to use for locking. The idea here is not to + * serialize the calls to select_pathway, so that as many + * operations can run concurrently as possible. To do that we use + * the CPT where this call is being executed. Later on when we + * determine the CPT to use in lnet_message_commit, we switch the + * lock and check if there was any configuration change. If none, + * then we proceed, if there is, then we restart the operation. + */ + cpt = lnet_net_lock_current(); + + md_cpt = lnet_cpt_of_md(msg->msg_md, msg->msg_offset); + if (md_cpt == CFS_CPT_ANY) + md_cpt = cpt; + +again: + + /* + * If we're being asked to send to the loopback interface, there + * is no need to go through any selection. We can just shortcut + * the entire process and send over lolnd + */ + send_data.sd_msg = msg; + send_data.sd_cpt = cpt; + if (LNET_NETTYP(LNET_NIDNET(dst_nid)) == LOLND) { + rc = lnet_handle_lo_send(&send_data); + lnet_net_unlock(cpt); + return rc; + } + + /* + * find an existing peer_ni, or create one and mark it as having been + * created due to network traffic. This call will create the + * peer->peer_net->peer_ni tree. + */ + lpni = lnet_nid2peerni_locked(dst_nid, LNET_NID_ANY, cpt); + if (IS_ERR(lpni)) { + lnet_net_unlock(cpt); + return PTR_ERR(lpni); + } + + /* + * Cache the original src_nid. If we need to resend the message + * then we'll need to know whether the src_nid was originally + * specified for this message. If it was originally specified, + * then we need to keep using the same src_nid since it's + * continuing the same sequence of messages. + */ + msg->msg_src_nid_param = src_nid; + + /* + * If necessary, perform discovery on the peer that owns this peer_ni. + * Note, this can result in the ownership of this peer_ni changing + * to another peer object. + */ + rc = lnet_initiate_peer_discovery(lpni, msg, rtr_nid, cpt); + if (rc) { + lnet_peer_ni_decref_locked(lpni); + lnet_net_unlock(cpt); + return rc; } + lnet_peer_ni_decref_locked(lpni); + + peer = lpni->lpni_peer_net->lpn_peer; + + /* + * Identify the different send cases + */ + if (src_nid == LNET_NID_ANY) + send_case |= SRC_ANY; + else + send_case |= SRC_SPEC; + + if (lnet_get_net_locked(LNET_NIDNET(dst_nid))) + send_case |= LOCAL_DST; + else + send_case |= REMOTE_DST; + + /* + * if this is a non-MR peer or if we're recovering a peer ni then + * let's consider this an NMR case so we can hit the destination + * NID. + */ + if (!lnet_peer_is_multi_rail(peer) || msg->msg_recovery) + send_case |= NMR_DST; + else + send_case |= MR_DST; if (msg->msg_type == LNET_MSG_REPLY || - msg->msg_type == LNET_MSG_ACK || - !lnet_peer_is_multi_rail(peer) || - best_ni) { + msg->msg_type == LNET_MSG_ACK) + send_case |= SND_RESP; + + /* assign parameters to the send_data */ + send_data.sd_rtr_nid = rtr_nid; + send_data.sd_src_nid = src_nid; + send_data.sd_dst_nid = dst_nid; + send_data.sd_best_lpni = lpni; + /* + * keep a pointer to the final destination in case we're going to + * route, so we'll need to access it later + */ + send_data.sd_final_dst_lpni = lpni; + send_data.sd_peer = peer; + send_data.sd_md_cpt = md_cpt; + send_data.sd_send_case = send_case; + + rc = lnet_handle_send_case_locked(&send_data); + + /* + * Update the local cpt since send_data.sd_cpt might've been + * updated as a result of calling lnet_handle_send_case_locked(). + */ + cpt = send_data.sd_cpt; + + if (rc == REPEAT_SEND) + goto again; + + lnet_net_unlock(cpt); + + return rc; +} + +int +lnet_send(lnet_nid_t src_nid, struct lnet_msg *msg, lnet_nid_t rtr_nid) +{ + lnet_nid_t dst_nid = msg->msg_target.nid; + int rc; + + /* + * NB: rtr_nid is set to LNET_NID_ANY for all current use-cases, + * but we might want to use pre-determined router for ACK/REPLY + * in the future + */ + /* NB: ni != NULL == interface pre-determined (ACK/REPLY) */ + LASSERT(msg->msg_txpeer == NULL); + LASSERT(msg->msg_txni == NULL); + LASSERT(!msg->msg_sending); + LASSERT(!msg->msg_target_is_router); + LASSERT(!msg->msg_receiving); + + msg->msg_sending = 1; + + LASSERT(!msg->msg_tx_committed); + + rc = lnet_select_pathway(src_nid, dst_nid, msg, rtr_nid); + if (rc < 0) { + if (rc == -EHOSTUNREACH) + msg->msg_health_status = LNET_MSG_STATUS_REMOTE_ERROR; + else + msg->msg_health_status = LNET_MSG_STATUS_LOCAL_ERROR; + return rc; + } + + if (rc == LNET_CREDIT_OK) + lnet_ni_send(msg->msg_txni, msg); + + /* rc == LNET_CREDIT_OK or LNET_CREDIT_WAIT or LNET_DC_WAIT */ + return 0; +} + +enum lnet_mt_event_type { + MT_TYPE_LOCAL_NI = 0, + MT_TYPE_PEER_NI +}; + +struct lnet_mt_event_info { + enum lnet_mt_event_type mt_type; + lnet_nid_t mt_nid; +}; + +/* called with res_lock held */ +void +lnet_detach_rsp_tracker(struct lnet_libmd *md, int cpt) +{ + struct lnet_rsp_tracker *rspt; + + /* + * msg has a refcount on the MD so the MD is not going away. + * The rspt queue for the cpt is protected by + * the lnet_net_lock(cpt). cpt is the cpt of the MD cookie. + */ + if (!md->md_rspt_ptr) + return; + + rspt = md->md_rspt_ptr; + + /* debug code */ + LASSERT(rspt->rspt_cpt == cpt); + + md->md_rspt_ptr = NULL; + + if (LNetMDHandleIsInvalid(rspt->rspt_mdh)) { /* - * for replies we want to respond on the same peer_ni we - * received the message on if possible. If not, then pick - * a peer_ni to send to - * - * if the peer is non-multi-rail then you want to send to - * the dst_nid provided as well. - * - * If the best_ni has already been determined, IE the - * src_nid has been specified, then use the - * destination_nid provided as well, since we're - * continuing a series of related messages for the same - * RPC. - * - * It is expected to find the lpni using dst_nid, since we - * created it earlier. + * The monitor thread has invalidated this handle because the + * response timed out, but it failed to lookup the MD. That + * means this response tracker is on the zombie list. We can + * safely remove it under the resource lock (held by caller) and + * free the response tracker block. */ - best_lpni = lnet_find_peer_ni_locked(dst_nid); - if (best_lpni) - lnet_peer_ni_decref_locked(best_lpni); + list_del(&rspt->rspt_on_list); + lnet_rspt_free(rspt, cpt); + } else { + /* + * invalidate the handle to indicate that a response has been + * received, which will then lead the monitor thread to clean up + * the rspt block. + */ + LNetInvalidateMDHandle(&rspt->rspt_mdh); + } +} + +void +lnet_clean_zombie_rstqs(void) +{ + struct lnet_rsp_tracker *rspt, *tmp; + int i; + + cfs_cpt_for_each(i, lnet_cpt_table()) { + list_for_each_entry_safe(rspt, tmp, + the_lnet.ln_mt_zombie_rstqs[i], + rspt_on_list) { + list_del(&rspt->rspt_on_list); + lnet_rspt_free(rspt, i); + } + } + + cfs_percpt_free(the_lnet.ln_mt_zombie_rstqs); +} + +static void +lnet_finalize_expired_responses(void) +{ + struct lnet_libmd *md; + struct lnet_rsp_tracker *rspt, *tmp; + ktime_t now; + int i; + + if (the_lnet.ln_mt_rstq == NULL) + return; + + cfs_cpt_for_each(i, lnet_cpt_table()) { + LIST_HEAD(local_queue); + + lnet_net_lock(i); + if (!the_lnet.ln_mt_rstq[i]) { + lnet_net_unlock(i); + continue; + } + list_splice_init(the_lnet.ln_mt_rstq[i], &local_queue); + lnet_net_unlock(i); + + now = ktime_get(); - if (best_lpni && !lnet_get_net_locked(LNET_NIDNET(dst_nid))) { + list_for_each_entry_safe(rspt, tmp, &local_queue, rspt_on_list) { /* - * this lpni is not on a local network so we need - * to route this reply. + * The rspt mdh will be invalidated when a response + * is received or whenever we want to discard the + * block the monitor thread will walk the queue + * and clean up any rsts with an invalid mdh. + * The monitor thread will walk the queue until + * the first unexpired rspt block. This means that + * some rspt blocks which received their + * corresponding responses will linger in the + * queue until they are cleaned up eventually. */ - best_gw = lnet_find_route_locked(NULL, - best_lpni->lpni_nid, - rtr_nid); - if (best_gw) { - /* - * RULE: Each node considers only the next-hop - * - * We're going to route the message, so change the peer to - * the router. - */ - LASSERT(best_gw->lpni_peer_net); - LASSERT(best_gw->lpni_peer_net->lpn_peer); - peer = best_gw->lpni_peer_net->lpn_peer; + lnet_res_lock(i); + if (LNetMDHandleIsInvalid(rspt->rspt_mdh)) { + lnet_res_unlock(i); + list_del(&rspt->rspt_on_list); + lnet_rspt_free(rspt, i); + continue; + } - /* - * if the router is not multi-rail then use the best_gw - * found to send the message to - */ - if (!lnet_peer_is_multi_rail(peer)) - best_lpni = best_gw; - else - best_lpni = NULL; + if (ktime_compare(now, rspt->rspt_deadline) >= 0 || + the_lnet.ln_mt_state == LNET_MT_STATE_SHUTDOWN) { + struct lnet_peer_ni *lpni; + lnet_nid_t nid; + + md = lnet_handle2md(&rspt->rspt_mdh); + if (!md) { + /* MD has been queued for unlink, but + * rspt hasn't been detached (Note we've + * checked above that the rspt_mdh is + * valid). Since we cannot lookup the MD + * we're unable to detach the rspt + * ourselves. Thus, move the rspt to the + * zombie list where we'll wait for + * either: + * 1. The remaining operations on the + * MD to complete. In this case the + * final operation will result in + * lnet_msg_detach_md()-> + * lnet_detach_rsp_tracker() where + * we will clean up this response + * tracker. + * 2. LNet to shutdown. In this case + * we'll wait until after all LND Nets + * have shutdown and then we can + * safely free any remaining response + * tracker blocks on the zombie list. + * Note: We need to hold the resource + * lock when adding to the zombie list + * because we may have concurrent access + * with lnet_detach_rsp_tracker(). + */ + LNetInvalidateMDHandle(&rspt->rspt_mdh); + list_move(&rspt->rspt_on_list, + the_lnet.ln_mt_zombie_rstqs[i]); + lnet_res_unlock(i); + continue; + } + LASSERT(md->md_rspt_ptr == rspt); + md->md_rspt_ptr = NULL; + lnet_res_unlock(i); + + LNetMDUnlink(rspt->rspt_mdh); + + nid = rspt->rspt_next_hop_nid; + + list_del(&rspt->rspt_on_list); + lnet_rspt_free(rspt, i); - routing = true; + /* If we're shutting down we just want to clean + * up the rspt blocks + */ + if (the_lnet.ln_mt_state == LNET_MT_STATE_SHUTDOWN) + continue; + + lnet_net_lock(i); + the_lnet.ln_counters[i]->lct_health.lch_response_timeout_count++; + lnet_net_unlock(i); + + CDEBUG(D_NET, + "Response timeout: md = %p: nid = %s\n", + md, libcfs_nid2str(nid)); + + /* + * If there is a timeout on the response + * from the next hop decrement its health + * value so that we don't use it + */ + lnet_net_lock(0); + lpni = lnet_find_peer_ni_locked(nid); + if (lpni) { + lnet_handle_remote_failure_locked(lpni); + lnet_peer_ni_decref_locked(lpni); + } + lnet_net_unlock(0); } else { - best_lpni = NULL; + lnet_res_unlock(i); + break; } - } else if (!best_lpni) { - lnet_net_unlock(cpt); - CERROR("unable to send msg_type %d to " - "originating %s. Destination NID not in DB\n", - msg->msg_type, libcfs_nid2str(dst_nid)); - return -EINVAL; + } + + if (!list_empty(&local_queue)) { + lnet_net_lock(i); + list_splice(&local_queue, the_lnet.ln_mt_rstq[i]); + lnet_net_unlock(i); } } +} - /* - * We must use a consistent source address when sending to a - * non-MR peer. However, a non-MR peer can have multiple NIDs - * on multiple networks, and we may even need to talk to this - * peer on multiple networks -- certain types of - * load-balancing configuration do this. - * - * So we need to pick the NI the peer prefers for this - * particular network. - */ - if (!lnet_peer_is_multi_rail(peer)) { - if (!best_lpni) { +static void +lnet_resend_pending_msgs_locked(struct list_head *resendq, int cpt) +{ + struct lnet_msg *msg; + + while (!list_empty(resendq)) { + struct lnet_peer_ni *lpni; + + msg = list_entry(resendq->next, struct lnet_msg, + msg_list); + + list_del_init(&msg->msg_list); + + lpni = lnet_find_peer_ni_locked(msg->msg_hdr.dest_nid); + if (!lpni) { lnet_net_unlock(cpt); - CERROR("no route to %s\n", - libcfs_nid2str(dst_nid)); - return -EHOSTUNREACH; - } + CERROR("Expected that a peer is already created for %s\n", + libcfs_nid2str(msg->msg_hdr.dest_nid)); + msg->msg_no_resend = true; + lnet_finalize(msg, -EFAULT); + lnet_net_lock(cpt); + } else { + struct lnet_peer *peer; + int rc; + lnet_nid_t src_nid = LNET_NID_ANY; - /* best ni is already set if src_nid was provided */ - if (!best_ni) { - /* Get the target peer_ni */ - peer_net = lnet_peer_get_net_locked(peer, - LNET_NIDNET(best_lpni->lpni_nid)); - LASSERT(peer_net != NULL); - list_for_each_entry(lpni, &peer_net->lpn_peer_nis, - lpni_peer_nis) { - if (lpni->lpni_pref_nnids == 0) - continue; - LASSERT(lpni->lpni_pref_nnids == 1); - best_ni = lnet_nid2ni_locked( - lpni->lpni_pref.nid, cpt); - break; - } - } - /* if best_ni is still not set just pick one */ - if (!best_ni) { - best_ni = lnet_net2ni_locked( - best_lpni->lpni_net->net_id, cpt); - /* If there is no best_ni we don't have a route */ - if (!best_ni) { - lnet_net_unlock(cpt); - CERROR("no path to %s from net %s\n", - libcfs_nid2str(best_lpni->lpni_nid), - libcfs_net2str(best_lpni->lpni_net->net_id)); - return -EHOSTUNREACH; + /* + * if this message is not being routed and the + * peer is non-MR then we must use the same + * src_nid that was used in the original send. + * Otherwise if we're routing the message (IE + * we're a router) then we can use any of our + * local interfaces. It doesn't matter to the + * final destination. + */ + peer = lpni->lpni_peer_net->lpn_peer; + if (!msg->msg_routing && + !lnet_peer_is_multi_rail(peer)) + src_nid = le64_to_cpu(msg->msg_hdr.src_nid); + + /* + * If we originally specified a src NID, then we + * must attempt to reuse it in the resend as well. + */ + if (msg->msg_src_nid_param != LNET_NID_ANY) + src_nid = msg->msg_src_nid_param; + lnet_peer_ni_decref_locked(lpni); + + lnet_net_unlock(cpt); + CDEBUG(D_NET, "resending %s->%s: %s recovery %d try# %d\n", + libcfs_nid2str(src_nid), + libcfs_id2str(msg->msg_target), + lnet_msgtyp2str(msg->msg_type), + msg->msg_recovery, + msg->msg_retry_count); + rc = lnet_send(src_nid, msg, LNET_NID_ANY); + if (rc) { + CERROR("Error sending %s to %s: %d\n", + lnet_msgtyp2str(msg->msg_type), + libcfs_id2str(msg->msg_target), rc); + msg->msg_no_resend = true; + lnet_finalize(msg, rc); } - lpni = list_entry(peer_net->lpn_peer_nis.next, - struct lnet_peer_ni, - lpni_peer_nis); + lnet_net_lock(cpt); + if (!rc) + the_lnet.ln_counters[cpt]->lct_health.lch_resend_count++; } - /* Set preferred NI if necessary. */ - if (lpni->lpni_pref_nnids == 0) - lnet_peer_ni_set_non_mr_pref_nid(lpni, best_ni->ni_nid); } +} - /* - * if we already found a best_ni because src_nid is specified and - * best_lpni because we are replying to a message then just send - * the message - */ - if (best_ni && best_lpni) - goto send; +static void +lnet_resend_pending_msgs(void) +{ + int i; - /* - * If we already found a best_ni because src_nid is specified then - * pick the peer then send the message - */ - if (best_ni) - goto pick_peer; + cfs_cpt_for_each(i, lnet_cpt_table()) { + lnet_net_lock(i); + lnet_resend_pending_msgs_locked(the_lnet.ln_mt_resendqs[i], i); + lnet_net_unlock(i); + } +} + +/* called with cpt and ni_lock held */ +static void +lnet_unlink_ni_recovery_mdh_locked(struct lnet_ni *ni, int cpt, bool force) +{ + struct lnet_handle_md recovery_mdh; + + LNetInvalidateMDHandle(&recovery_mdh); + + if (ni->ni_recovery_state & LNET_NI_RECOVERY_PENDING || + force) { + recovery_mdh = ni->ni_ping_mdh; + LNetInvalidateMDHandle(&ni->ni_ping_mdh); + } + lnet_ni_unlock(ni); + lnet_net_unlock(cpt); + if (!LNetMDHandleIsInvalid(recovery_mdh)) + LNetMDUnlink(recovery_mdh); + lnet_net_lock(cpt); + lnet_ni_lock(ni); +} + +static void +lnet_recover_local_nis(void) +{ + struct lnet_mt_event_info *ev_info; + LIST_HEAD(processed_list); + LIST_HEAD(local_queue); + struct lnet_handle_md mdh; + struct lnet_ni *tmp; + struct lnet_ni *ni; + lnet_nid_t nid; + int healthv; + int rc; /* - * pick the best_ni by going through all the possible networks of - * that peer and see which local NI is best suited to talk to that - * peer. - * - * Locally connected networks will always be preferred over - * a routed network. If there are only routed paths to the peer, - * then the best route is chosen. If all routes are equal then - * they are used in round robin. + * splice the recovery queue on a local queue. We will iterate + * through the local queue and update it as needed. Once we're + * done with the traversal, we'll splice the local queue back on + * the head of the ln_mt_localNIRecovq. Any newly added local NIs + * will be traversed in the next iteration. */ - list_for_each_entry(peer_net, &peer->lp_peer_nets, lpn_peer_nets) { - if (!lnet_is_peer_net_healthy_locked(peer_net)) + lnet_net_lock(0); + list_splice_init(&the_lnet.ln_mt_localNIRecovq, + &local_queue); + lnet_net_unlock(0); + + list_for_each_entry_safe(ni, tmp, &local_queue, ni_recovery) { + /* + * if an NI is being deleted or it is now healthy, there + * is no need to keep it around in the recovery queue. + * The monitor thread is the only thread responsible for + * removing the NI from the recovery queue. + * Multiple threads can be adding NIs to the recovery + * queue. + */ + healthv = atomic_read(&ni->ni_healthv); + + lnet_net_lock(0); + lnet_ni_lock(ni); + if (ni->ni_state != LNET_NI_STATE_ACTIVE || + healthv == LNET_MAX_HEALTH_VALUE) { + list_del_init(&ni->ni_recovery); + lnet_unlink_ni_recovery_mdh_locked(ni, 0, false); + lnet_ni_unlock(ni); + lnet_ni_decref_locked(ni, 0); + lnet_net_unlock(0); continue; + } + + /* + * if the local NI failed recovery we must unlink the md. + * But we want to keep the local_ni on the recovery queue + * so we can continue the attempts to recover it. + */ + if (ni->ni_recovery_state & LNET_NI_RECOVERY_FAILED) { + lnet_unlink_ni_recovery_mdh_locked(ni, 0, true); + ni->ni_recovery_state &= ~LNET_NI_RECOVERY_FAILED; + } - local_net = lnet_get_net_locked(peer_net->lpn_net_id); - if (!local_net && !routing && !local_found) { - struct lnet_peer_ni *net_gw; + lnet_ni_unlock(ni); + lnet_net_unlock(0); - lpni = list_entry(peer_net->lpn_peer_nis.next, - struct lnet_peer_ni, - lpni_peer_nis); - net_gw = lnet_find_route_locked(NULL, - lpni->lpni_nid, - rtr_nid); - if (!net_gw) + CDEBUG(D_NET, "attempting to recover local ni: %s\n", + libcfs_nid2str(ni->ni_nid)); + + lnet_ni_lock(ni); + if (!(ni->ni_recovery_state & LNET_NI_RECOVERY_PENDING)) { + ni->ni_recovery_state |= LNET_NI_RECOVERY_PENDING; + lnet_ni_unlock(ni); + + LIBCFS_ALLOC(ev_info, sizeof(*ev_info)); + if (!ev_info) { + CERROR("out of memory. Can't recover %s\n", + libcfs_nid2str(ni->ni_nid)); + lnet_ni_lock(ni); + ni->ni_recovery_state &= + ~LNET_NI_RECOVERY_PENDING; + lnet_ni_unlock(ni); continue; + } + + mdh = ni->ni_ping_mdh; + /* + * Invalidate the ni mdh in case it's deleted. + * We'll unlink the mdh in this case below. + */ + LNetInvalidateMDHandle(&ni->ni_ping_mdh); + nid = ni->ni_nid; - if (best_gw) { + /* + * remove the NI from the local queue and drop the + * reference count to it while we're recovering + * it. The reason for that, is that the NI could + * be deleted, and the way the code is structured + * is if we don't drop the NI, then the deletion + * code will enter a loop waiting for the + * reference count to be removed while holding the + * ln_mutex_lock(). When we look up the peer to + * send to in lnet_select_pathway() we will try to + * lock the ln_mutex_lock() as well, leading to + * a deadlock. By dropping the refcount and + * removing it from the list, we allow for the NI + * to be removed, then we use the cached NID to + * look it up again. If it's gone, then we just + * continue examining the rest of the queue. + */ + lnet_net_lock(0); + list_del_init(&ni->ni_recovery); + lnet_ni_decref_locked(ni, 0); + lnet_net_unlock(0); + + ev_info->mt_type = MT_TYPE_LOCAL_NI; + ev_info->mt_nid = nid; + rc = lnet_send_ping(nid, &mdh, LNET_INTERFACES_MIN, + ev_info, the_lnet.ln_mt_eqh, true); + /* lookup the nid again */ + lnet_net_lock(0); + ni = lnet_nid2ni_locked(nid, 0); + if (!ni) { /* - * lnet_find_route_locked() call - * will return the best_Gw on the - * lpni->lpni_nid network. - * However, best_gw and net_gw can - * be on different networks. - * Therefore need to compare them - * to pick the better of either. + * the NI has been deleted when we dropped + * the ref count */ - if (lnet_compare_peers(best_gw, net_gw) > 0) - continue; - if (best_gw->lpni_gw_seq <= net_gw->lpni_gw_seq) - continue; + lnet_net_unlock(0); + LNetMDUnlink(mdh); + continue; + } + /* + * Same note as in lnet_recover_peer_nis(). When + * we're sending the ping, the NI is free to be + * deleted or manipulated. By this point it + * could've been added back on the recovery queue, + * and a refcount taken on it. + * So we can't just add it blindly again or we'll + * corrupt the queue. We must check under lock if + * it's not on any list and if not then add it + * to the processed list, which will eventually be + * spliced back on to the recovery queue. + */ + ni->ni_ping_mdh = mdh; + if (list_empty(&ni->ni_recovery)) { + list_add_tail(&ni->ni_recovery, &processed_list); + lnet_ni_addref_locked(ni, 0); } - best_gw = net_gw; - final_dst = lpni; + lnet_net_unlock(0); - routing2 = true; - } else { - best_gw = NULL; - final_dst = NULL; - routing2 = false; - local_found = true; + lnet_ni_lock(ni); + if (rc) + ni->ni_recovery_state &= ~LNET_NI_RECOVERY_PENDING; } + lnet_ni_unlock(ni); + } - /* - * a gw on this network is found, but there could be - * other better gateways on other networks. So don't pick - * the best_ni until we determine the best_gw. - */ - if (best_gw) - continue; + /* + * put back the remaining NIs on the ln_mt_localNIRecovq to be + * reexamined in the next iteration. + */ + list_splice_init(&processed_list, &local_queue); + lnet_net_lock(0); + list_splice(&local_queue, &the_lnet.ln_mt_localNIRecovq); + lnet_net_unlock(0); +} - /* if no local_net found continue */ - if (!local_net) - continue; +static int +lnet_resendqs_create(void) +{ + struct list_head **resendqs; + resendqs = lnet_create_array_of_queues(); - /* - * Iterate through the NIs in this local Net and select - * the NI to send from. The selection is determined by - * these 3 criterion in the following priority: - * 1. NUMA - * 2. NI available credits - * 3. Round Robin - */ - best_ni = lnet_get_best_ni(local_net, best_ni, md_cpt); + if (!resendqs) + return -ENOMEM; + + lnet_net_lock(LNET_LOCK_EX); + the_lnet.ln_mt_resendqs = resendqs; + lnet_net_unlock(LNET_LOCK_EX); + + return 0; +} + +static void +lnet_clean_local_ni_recoveryq(void) +{ + struct lnet_ni *ni; + + /* This is only called when the monitor thread has stopped */ + lnet_net_lock(0); + + while (!list_empty(&the_lnet.ln_mt_localNIRecovq)) { + ni = list_entry(the_lnet.ln_mt_localNIRecovq.next, + struct lnet_ni, ni_recovery); + list_del_init(&ni->ni_recovery); + lnet_ni_lock(ni); + lnet_unlink_ni_recovery_mdh_locked(ni, 0, true); + lnet_ni_unlock(ni); + lnet_ni_decref_locked(ni, 0); } - if (!best_ni && !best_gw) { - lnet_net_unlock(cpt); - LCONSOLE_WARN("No local ni found to send from to %s\n", - libcfs_nid2str(dst_nid)); - return -EINVAL; + lnet_net_unlock(0); +} + +static void +lnet_unlink_lpni_recovery_mdh_locked(struct lnet_peer_ni *lpni, int cpt, + bool force) +{ + struct lnet_handle_md recovery_mdh; + + LNetInvalidateMDHandle(&recovery_mdh); + + if (lpni->lpni_state & LNET_PEER_NI_RECOVERY_PENDING || force) { + recovery_mdh = lpni->lpni_recovery_ping_mdh; + LNetInvalidateMDHandle(&lpni->lpni_recovery_ping_mdh); + } + spin_unlock(&lpni->lpni_lock); + lnet_net_unlock(cpt); + if (!LNetMDHandleIsInvalid(recovery_mdh)) + LNetMDUnlink(recovery_mdh); + lnet_net_lock(cpt); + spin_lock(&lpni->lpni_lock); +} + +static void +lnet_clean_peer_ni_recoveryq(void) +{ + struct lnet_peer_ni *lpni, *tmp; + + lnet_net_lock(LNET_LOCK_EX); + + list_for_each_entry_safe(lpni, tmp, &the_lnet.ln_mt_peerNIRecovq, + lpni_recovery) { + list_del_init(&lpni->lpni_recovery); + spin_lock(&lpni->lpni_lock); + lnet_unlink_lpni_recovery_mdh_locked(lpni, LNET_LOCK_EX, true); + spin_unlock(&lpni->lpni_lock); + lnet_peer_ni_decref_locked(lpni); } - if (!best_ni) { - best_ni = lnet_get_best_ni(best_gw->lpni_net, best_ni, md_cpt); - LASSERT(best_gw && best_ni); + lnet_net_unlock(LNET_LOCK_EX); +} - /* - * We're going to route the message, so change the peer to - * the router. - */ - LASSERT(best_gw->lpni_peer_net); - LASSERT(best_gw->lpni_peer_net->lpn_peer); - best_gw->lpni_gw_seq++; - peer = best_gw->lpni_peer_net->lpn_peer; +static void +lnet_clean_resendqs(void) +{ + struct lnet_msg *msg, *tmp; + LIST_HEAD(msgs); + int i; + + cfs_cpt_for_each(i, lnet_cpt_table()) { + lnet_net_lock(i); + list_splice_init(the_lnet.ln_mt_resendqs[i], &msgs); + lnet_net_unlock(i); + list_for_each_entry_safe(msg, tmp, &msgs, msg_list) { + list_del_init(&msg->msg_list); + msg->msg_no_resend = true; + lnet_finalize(msg, -ESHUTDOWN); + } } - /* - * Now that we selected the NI to use increment its sequence - * number so the Round Robin algorithm will detect that it has - * been used and pick the next NI. - */ - best_ni->ni_seq++; + cfs_percpt_free(the_lnet.ln_mt_resendqs); +} + +static void +lnet_recover_peer_nis(void) +{ + struct lnet_mt_event_info *ev_info; + LIST_HEAD(processed_list); + LIST_HEAD(local_queue); + struct lnet_handle_md mdh; + struct lnet_peer_ni *lpni; + struct lnet_peer_ni *tmp; + lnet_nid_t nid; + int healthv; + int rc; -pick_peer: - /* - * At this point the best_ni is on a local network on which - * the peer has a peer_ni as well - */ - peer_net = lnet_peer_get_net_locked(peer, - best_ni->ni_net->net_id); /* - * peer_net is not available or the src_nid is explicitly defined - * and the peer_net for that src_nid is unhealthy. find a route to - * the destination nid. + * Always use cpt 0 for locking across all interactions with + * ln_mt_peerNIRecovq */ - if (!peer_net || - (src_nid != LNET_NID_ANY && - !lnet_is_peer_net_healthy_locked(peer_net))) { - best_gw = lnet_find_route_locked(best_ni->ni_net, - dst_nid, - rtr_nid); + lnet_net_lock(0); + list_splice_init(&the_lnet.ln_mt_peerNIRecovq, + &local_queue); + lnet_net_unlock(0); + + list_for_each_entry_safe(lpni, tmp, &local_queue, + lpni_recovery) { /* - * if no route is found for that network then - * move onto the next peer_ni in the peer + * The same protection strategy is used here as is in the + * local recovery case. */ - if (!best_gw) { - lnet_net_unlock(cpt); - LCONSOLE_WARN("No route to peer from %s\n", - libcfs_nid2str(best_ni->ni_nid)); - return -EHOSTUNREACH; + lnet_net_lock(0); + healthv = atomic_read(&lpni->lpni_healthv); + spin_lock(&lpni->lpni_lock); + if (lpni->lpni_state & LNET_PEER_NI_DELETING || + healthv == LNET_MAX_HEALTH_VALUE) { + list_del_init(&lpni->lpni_recovery); + lnet_unlink_lpni_recovery_mdh_locked(lpni, 0, false); + spin_unlock(&lpni->lpni_lock); + lnet_peer_ni_decref_locked(lpni); + lnet_net_unlock(0); + continue; } - CDEBUG(D_NET, "Best route to %s via %s for %s %d\n", - libcfs_nid2str(dst_nid), - libcfs_nid2str(best_gw->lpni_nid), - lnet_msgtyp2str(msg->msg_type), msg->msg_len); - - routing2 = true; - /* - * RULE: Each node considers only the next-hop - * - * We're going to route the message, so change the peer to - * the router. - */ - LASSERT(best_gw->lpni_peer_net); - LASSERT(best_gw->lpni_peer_net->lpn_peer); - peer = best_gw->lpni_peer_net->lpn_peer; - } else if (!lnet_is_peer_net_healthy_locked(peer_net)) { /* - * this peer_net is unhealthy but we still have an opportunity - * to find another peer_net that we can use + * If the peer NI has failed recovery we must unlink the + * md. But we want to keep the peer ni on the recovery + * queue so we can try to continue recovering it */ - __u32 net_id = peer_net->lpn_net_id; - LCONSOLE_WARN("peer net %s unhealthy\n", - libcfs_net2str(net_id)); - goto again; - } + if (lpni->lpni_state & LNET_PEER_NI_RECOVERY_FAILED) { + lnet_unlink_lpni_recovery_mdh_locked(lpni, 0, true); + lpni->lpni_state &= ~LNET_PEER_NI_RECOVERY_FAILED; + } + + spin_unlock(&lpni->lpni_lock); + lnet_net_unlock(0); - /* - * Look at the peer NIs for the destination peer that connect - * to the chosen net. If a peer_ni is preferred when using the - * best_ni to communicate, we use that one. If there is no - * preferred peer_ni, or there are multiple preferred peer_ni, - * the available transmit credits are used. If the transmit - * credits are equal, we round-robin over the peer_ni. - */ - lpni = NULL; - best_lpni_credits = INT_MIN; - preferred = false; - best_lpni = NULL; - while ((lpni = lnet_get_next_peer_ni_locked(peer, peer_net, lpni))) { /* - * if this peer ni is not healthy just skip it, no point in - * examining it further + * NOTE: we're racing with peer deletion from user space. + * It's possible that a peer is deleted after we check its + * state. In this case the recovery can create a new peer */ - if (!lnet_is_peer_ni_healthy_locked(lpni)) - continue; - ni_is_pref = lnet_peer_is_pref_nid_locked(lpni, - best_ni->ni_nid); + spin_lock(&lpni->lpni_lock); + if (!(lpni->lpni_state & LNET_PEER_NI_RECOVERY_PENDING) && + !(lpni->lpni_state & LNET_PEER_NI_DELETING)) { + lpni->lpni_state |= LNET_PEER_NI_RECOVERY_PENDING; + spin_unlock(&lpni->lpni_lock); + + LIBCFS_ALLOC(ev_info, sizeof(*ev_info)); + if (!ev_info) { + CERROR("out of memory. Can't recover %s\n", + libcfs_nid2str(lpni->lpni_nid)); + spin_lock(&lpni->lpni_lock); + lpni->lpni_state &= ~LNET_PEER_NI_RECOVERY_PENDING; + spin_unlock(&lpni->lpni_lock); + continue; + } - /* if this is a preferred peer use it */ - if (!preferred && ni_is_pref) { - preferred = true; - } else if (preferred && !ni_is_pref) { - /* - * this is not the preferred peer so let's ignore - * it. - */ - continue; - } else if (lpni->lpni_txcredits < best_lpni_credits) { + /* look at the comments in lnet_recover_local_nis() */ + mdh = lpni->lpni_recovery_ping_mdh; + LNetInvalidateMDHandle(&lpni->lpni_recovery_ping_mdh); + nid = lpni->lpni_nid; + lnet_net_lock(0); + list_del_init(&lpni->lpni_recovery); + lnet_peer_ni_decref_locked(lpni); + lnet_net_unlock(0); + + ev_info->mt_type = MT_TYPE_PEER_NI; + ev_info->mt_nid = nid; + rc = lnet_send_ping(nid, &mdh, LNET_INTERFACES_MIN, + ev_info, the_lnet.ln_mt_eqh, true); + lnet_net_lock(0); /* - * We already have a peer that has more credits - * available than this one. No need to consider - * this peer further. + * lnet_find_peer_ni_locked() grabs a refcount for + * us. No need to take it explicitly. */ - continue; - } else if (lpni->lpni_txcredits == best_lpni_credits) { + lpni = lnet_find_peer_ni_locked(nid); + if (!lpni) { + lnet_net_unlock(0); + LNetMDUnlink(mdh); + continue; + } + + lpni->lpni_recovery_ping_mdh = mdh; /* - * The best peer found so far and the current peer - * have the same number of available credits let's - * make sure to select between them using Round - * Robin + * While we're unlocked the lpni could've been + * readded on the recovery queue. In this case we + * don't need to add it to the local queue, since + * it's already on there and the thread that added + * it would've incremented the refcount on the + * peer, which means we need to decref the refcount + * that was implicitly grabbed by find_peer_ni_locked. + * Otherwise, if the lpni is still not on + * the recovery queue, then we'll add it to the + * processed list. */ - if (best_lpni) { - if (best_lpni->lpni_seq <= lpni->lpni_seq) - continue; - } + if (list_empty(&lpni->lpni_recovery)) + list_add_tail(&lpni->lpni_recovery, &processed_list); + else + lnet_peer_ni_decref_locked(lpni); + lnet_net_unlock(0); + + spin_lock(&lpni->lpni_lock); + if (rc) + lpni->lpni_state &= ~LNET_PEER_NI_RECOVERY_PENDING; + } + spin_unlock(&lpni->lpni_lock); + } + + list_splice_init(&processed_list, &local_queue); + lnet_net_lock(0); + list_splice(&local_queue, &the_lnet.ln_mt_peerNIRecovq); + lnet_net_unlock(0); +} + +static int +lnet_monitor_thread(void *arg) +{ + time64_t recovery_timeout = 0; + time64_t rsp_timeout = 0; + int interval; + time64_t now; + + wait_for_completion(&the_lnet.ln_started); + /* + * The monitor thread takes care of the following: + * 1. Checks the aliveness of routers + * 2. Checks if there are messages on the resend queue to resend + * them. + * 3. Check if there are any NIs on the local recovery queue and + * pings them + * 4. Checks if there are any NIs on the remote recovery queue + * and pings them. + */ + cfs_block_allsigs(); + + while (the_lnet.ln_mt_state == LNET_MT_STATE_RUNNING) { + now = ktime_get_real_seconds(); + + if (lnet_router_checker_active()) + lnet_check_routers(); + + lnet_resend_pending_msgs(); + + if (now >= rsp_timeout) { + lnet_finalize_expired_responses(); + rsp_timeout = now + (lnet_transaction_timeout / 2); } - best_lpni = lpni; - best_lpni_credits = lpni->lpni_txcredits; - } + if (now >= recovery_timeout) { + lnet_recover_local_nis(); + lnet_recover_peer_nis(); + recovery_timeout = now + lnet_recovery_interval; + } - /* if we still can't find a peer ni then we can't reach it */ - if (!best_lpni) { - __u32 net_id = (peer_net) ? peer_net->lpn_net_id : - LNET_NIDNET(dst_nid); - lnet_net_unlock(cpt); - LCONSOLE_WARN("no peer_ni found on peer net %s\n", - libcfs_net2str(net_id)); - return -EHOSTUNREACH; + /* + * TODO do we need to check if we should sleep without + * timeout? Technically, an active system will always + * have messages in flight so this check will always + * evaluate to false. And on an idle system do we care + * if we wake up every 1 second? Although, we've seen + * cases where we get a complaint that an idle thread + * is waking up unnecessarily. + * + * Take into account the current net_count when you wake + * up for alive router checking, since we need to check + * possibly as many networks as we have configured. + */ + interval = min(lnet_recovery_interval, + min((unsigned int) alive_router_check_interval / + lnet_current_net_count, + lnet_transaction_timeout / 2)); + wait_for_completion_interruptible_timeout( + &the_lnet.ln_mt_wait_complete, + cfs_time_seconds(interval)); + /* Must re-init the completion before testing anything, + * including ln_mt_state. + */ + reinit_completion(&the_lnet.ln_mt_wait_complete); } + /* Shutting down */ + lnet_net_lock(LNET_LOCK_EX); + the_lnet.ln_mt_state = LNET_MT_STATE_SHUTDOWN; + lnet_net_unlock(LNET_LOCK_EX); -send: - /* Shortcut for loopback. */ - if (best_ni == the_lnet.ln_loni) { - /* No send credit hassles with LOLND */ - lnet_ni_addref_locked(best_ni, cpt); - msg->msg_hdr.dest_nid = cpu_to_le64(best_ni->ni_nid); - if (!msg->msg_routing) - msg->msg_hdr.src_nid = cpu_to_le64(best_ni->ni_nid); - msg->msg_target.nid = best_ni->ni_nid; - lnet_msg_commit(msg, cpt); - msg->msg_txni = best_ni; - lnet_net_unlock(cpt); + /* signal that the monitor thread is exiting */ + up(&the_lnet.ln_mt_signal); - return LNET_CREDIT_OK; - } + return 0; +} - routing = routing || routing2; +/* + * lnet_send_ping + * Sends a ping. + * Returns == 0 if success + * Returns > 0 if LNetMDBind or prior fails + * Returns < 0 if LNetGet fails + */ +int +lnet_send_ping(lnet_nid_t dest_nid, + struct lnet_handle_md *mdh, int nnis, + void *user_data, struct lnet_handle_eq eqh, bool recovery) +{ + struct lnet_md md = { NULL }; + struct lnet_process_id id; + struct lnet_ping_buffer *pbuf; + int rc; - /* - * Increment sequence number of the peer selected so that we - * pick the next one in Round Robin. - */ - best_lpni->lpni_seq++; + if (dest_nid == LNET_NID_ANY) { + rc = -EHOSTUNREACH; + goto fail_error; + } - /* - * grab a reference on the peer_ni so it sticks around even if - * we need to drop and relock the lnet_net_lock below. - */ - lnet_peer_ni_addref_locked(best_lpni); + pbuf = lnet_ping_buffer_alloc(nnis, GFP_NOFS); + if (!pbuf) { + rc = ENOMEM; + goto fail_error; + } - /* - * Use lnet_cpt_of_nid() to determine the CPT used to commit the - * message. This ensures that we get a CPT that is correct for - * the NI when the NI has been restricted to a subset of all CPTs. - * If the selected CPT differs from the one currently locked, we - * must unlock and relock the lnet_net_lock(), and then check whether - * the configuration has changed. We don't have a hold on the best_ni - * yet, and it may have vanished. - */ - cpt2 = lnet_cpt_of_nid_locked(best_lpni->lpni_nid, best_ni); - if (cpt != cpt2) { - __u32 seq = lnet_get_dlc_seq_locked(); - lnet_net_unlock(cpt); - cpt = cpt2; - lnet_net_lock(cpt); - if (seq != lnet_get_dlc_seq_locked()) { - lnet_peer_ni_decref_locked(best_lpni); - goto again; - } + /* initialize md content */ + md.start = &pbuf->pb_info; + md.length = LNET_PING_INFO_SIZE(nnis); + md.threshold = 2; /* GET/REPLY */ + md.max_size = 0; + md.options = LNET_MD_TRUNCATE; + md.user_ptr = user_data; + md.eq_handle = eqh; + + rc = LNetMDBind(md, LNET_UNLINK, mdh); + if (rc) { + lnet_ping_buffer_decref(pbuf); + CERROR("Can't bind MD: %d\n", rc); + rc = -rc; /* change the rc to positive */ + goto fail_error; } + id.pid = LNET_PID_LUSTRE; + id.nid = dest_nid; - /* - * store the best_lpni in the message right away to avoid having - * to do the same operation under different conditions - */ - msg->msg_txpeer = best_lpni; - msg->msg_txni = best_ni; + rc = LNetGet(LNET_NID_ANY, *mdh, id, + LNET_RESERVED_PORTAL, + LNET_PROTO_PING_MATCHBITS, 0, recovery); - /* - * grab a reference for the best_ni since now it's in use in this - * send. the reference will need to be dropped when the message is - * finished in lnet_finalize() - */ - lnet_ni_addref_locked(msg->msg_txni, cpt); + if (rc) + goto fail_unlink_md; - /* - * Always set the target.nid to the best peer picked. Either the - * nid will be one of the preconfigured NIDs, or the same NID as - * what was originally set in the target or it will be the NID of - * a router if this message should be routed - */ - msg->msg_target.nid = msg->msg_txpeer->lpni_nid; + return 0; - /* - * lnet_msg_commit assigns the correct cpt to the message, which - * is used to decrement the correct refcount on the ni when it's - * time to return the credits - */ - lnet_msg_commit(msg, cpt); +fail_unlink_md: + LNetMDUnlink(*mdh); + LNetInvalidateMDHandle(mdh); +fail_error: + return rc; +} - /* - * If we are routing the message then we don't need to overwrite - * the src_nid since it would've been set at the origin. Otherwise - * we are the originator so we need to set it. - */ - if (!msg->msg_routing) - msg->msg_hdr.src_nid = cpu_to_le64(msg->msg_txni->ni_nid); +static void +lnet_handle_recovery_reply(struct lnet_mt_event_info *ev_info, + int status, bool unlink_event) +{ + lnet_nid_t nid = ev_info->mt_nid; - if (routing) { - msg->msg_target_is_router = 1; - msg->msg_target.pid = LNET_PID_LUSTRE; + if (ev_info->mt_type == MT_TYPE_LOCAL_NI) { + struct lnet_ni *ni; + + lnet_net_lock(0); + ni = lnet_nid2ni_locked(nid, 0); + if (!ni) { + lnet_net_unlock(0); + return; + } + lnet_ni_lock(ni); + ni->ni_recovery_state &= ~LNET_NI_RECOVERY_PENDING; + if (status) + ni->ni_recovery_state |= LNET_NI_RECOVERY_FAILED; + lnet_ni_unlock(ni); + lnet_net_unlock(0); + + if (status != 0) { + CERROR("local NI (%s) recovery failed with %d\n", + libcfs_nid2str(nid), status); + return; + } /* - * since we're routing we want to ensure that the - * msg_hdr.dest_nid is set to the final destination. When - * the router receives this message it knows how to route - * it. + * need to increment healthv for the ni here, because in + * the lnet_finalize() path we don't have access to this + * NI. And in order to get access to it, we'll need to + * carry forward too much information. + * In the peer case, it'll naturally be incremented */ - msg->msg_hdr.dest_nid = - cpu_to_le64(final_dst ? final_dst->lpni_nid : dst_nid); + if (!unlink_event) + lnet_inc_healthv(&ni->ni_healthv); } else { - /* - * if we're not routing set the dest_nid to the best peer - * ni that we picked earlier in the algorithm. - */ - msg->msg_hdr.dest_nid = cpu_to_le64(msg->msg_txpeer->lpni_nid); + struct lnet_peer_ni *lpni; + int cpt; + + cpt = lnet_net_lock_current(); + lpni = lnet_find_peer_ni_locked(nid); + if (!lpni) { + lnet_net_unlock(cpt); + return; + } + spin_lock(&lpni->lpni_lock); + lpni->lpni_state &= ~LNET_PEER_NI_RECOVERY_PENDING; + if (status) + lpni->lpni_state |= LNET_PEER_NI_RECOVERY_FAILED; + spin_unlock(&lpni->lpni_lock); + lnet_peer_ni_decref_locked(lpni); + lnet_net_unlock(cpt); + + if (status != 0) + CERROR("peer NI (%s) recovery failed with %d\n", + libcfs_nid2str(nid), status); } +} - rc = lnet_post_send_locked(msg, 0); +void +lnet_mt_event_handler(struct lnet_event *event) +{ + struct lnet_mt_event_info *ev_info = event->md.user_ptr; + struct lnet_ping_buffer *pbuf; + + /* TODO: remove assert */ + LASSERT(event->type == LNET_EVENT_REPLY || + event->type == LNET_EVENT_SEND || + event->type == LNET_EVENT_UNLINK); + + CDEBUG(D_NET, "Received event: %d status: %d\n", event->type, + event->status); + + switch (event->type) { + case LNET_EVENT_UNLINK: + CDEBUG(D_NET, "%s recovery ping unlinked\n", + libcfs_nid2str(ev_info->mt_nid)); + /* fallthrough */ + case LNET_EVENT_REPLY: + lnet_handle_recovery_reply(ev_info, event->status, + event->type == LNET_EVENT_UNLINK); + break; + case LNET_EVENT_SEND: + CDEBUG(D_NET, "%s recovery message sent %s:%d\n", + libcfs_nid2str(ev_info->mt_nid), + (event->status) ? "unsuccessfully" : + "successfully", event->status); + break; + default: + CERROR("Unexpected event: %d\n", event->type); + break; + } + if (event->unlinked) { + LIBCFS_FREE(ev_info, sizeof(*ev_info)); + pbuf = LNET_PING_INFO_TO_BUFFER(event->md.start); + lnet_ping_buffer_decref(pbuf); + } +} - if (!rc) - CDEBUG(D_NET, "TRACE: %s(%s:%s) -> %s(%s:%s) : %s\n", - libcfs_nid2str(msg->msg_hdr.src_nid), - libcfs_nid2str(msg->msg_txni->ni_nid), - libcfs_nid2str(src_nid), - libcfs_nid2str(msg->msg_hdr.dest_nid), - libcfs_nid2str(dst_nid), - libcfs_nid2str(msg->msg_txpeer->lpni_nid), - lnet_msgtyp2str(msg->msg_type)); +static int +lnet_rsp_tracker_create(void) +{ + struct list_head **rstqs; + rstqs = lnet_create_array_of_queues(); - lnet_net_unlock(cpt); + if (!rstqs) + return -ENOMEM; - return rc; + the_lnet.ln_mt_rstq = rstqs; + + return 0; } -int -lnet_send(lnet_nid_t src_nid, struct lnet_msg *msg, lnet_nid_t rtr_nid) +static void +lnet_rsp_tracker_clean(void) { - lnet_nid_t dst_nid = msg->msg_target.nid; - int rc; + lnet_finalize_expired_responses(); - /* - * NB: rtr_nid is set to LNET_NID_ANY for all current use-cases, - * but we might want to use pre-determined router for ACK/REPLY - * in the future - */ - /* NB: ni != NULL == interface pre-determined (ACK/REPLY) */ - LASSERT (msg->msg_txpeer == NULL); - LASSERT (!msg->msg_sending); - LASSERT (!msg->msg_target_is_router); - LASSERT (!msg->msg_receiving); + cfs_percpt_free(the_lnet.ln_mt_rstq); + the_lnet.ln_mt_rstq = NULL; +} - msg->msg_sending = 1; +int lnet_monitor_thr_start(void) +{ + int rc = 0; + struct task_struct *task; - LASSERT(!msg->msg_tx_committed); + if (the_lnet.ln_mt_state != LNET_MT_STATE_SHUTDOWN) + return -EALREADY; - rc = lnet_select_pathway(src_nid, dst_nid, msg, rtr_nid); - if (rc < 0) + rc = lnet_resendqs_create(); + if (rc) return rc; - if (rc == LNET_CREDIT_OK) - lnet_ni_send(msg->msg_txni, msg); + rc = lnet_rsp_tracker_create(); + if (rc) + goto clean_queues; + + sema_init(&the_lnet.ln_mt_signal, 0); + + lnet_net_lock(LNET_LOCK_EX); + the_lnet.ln_mt_state = LNET_MT_STATE_RUNNING; + lnet_net_unlock(LNET_LOCK_EX); + task = kthread_run(lnet_monitor_thread, NULL, "monitor_thread"); + if (IS_ERR(task)) { + rc = PTR_ERR(task); + CERROR("Can't start monitor thread: %d\n", rc); + goto clean_thread; + } - /* rc == LNET_CREDIT_OK or LNET_CREDIT_WAIT or LNET_DC_WAIT */ return 0; + +clean_thread: + lnet_net_lock(LNET_LOCK_EX); + the_lnet.ln_mt_state = LNET_MT_STATE_STOPPING; + lnet_net_unlock(LNET_LOCK_EX); + /* block until event callback signals exit */ + down(&the_lnet.ln_mt_signal); + /* clean up */ + lnet_net_lock(LNET_LOCK_EX); + the_lnet.ln_mt_state = LNET_MT_STATE_SHUTDOWN; + lnet_net_unlock(LNET_LOCK_EX); + lnet_rsp_tracker_clean(); + lnet_clean_local_ni_recoveryq(); + lnet_clean_peer_ni_recoveryq(); + lnet_clean_resendqs(); + LNetInvalidateEQHandle(&the_lnet.ln_mt_eqh); + return rc; +clean_queues: + lnet_rsp_tracker_clean(); + lnet_clean_local_ni_recoveryq(); + lnet_clean_peer_ni_recoveryq(); + lnet_clean_resendqs(); + return rc; +} + +void lnet_monitor_thr_stop(void) +{ + if (the_lnet.ln_mt_state == LNET_MT_STATE_SHUTDOWN) + return; + + LASSERT(the_lnet.ln_mt_state == LNET_MT_STATE_RUNNING); + lnet_net_lock(LNET_LOCK_EX); + the_lnet.ln_mt_state = LNET_MT_STATE_STOPPING; + lnet_net_unlock(LNET_LOCK_EX); + + /* tell the monitor thread that we're shutting down */ + complete(&the_lnet.ln_mt_wait_complete); + + /* block until monitor thread signals that it's done */ + down(&the_lnet.ln_mt_signal); + LASSERT(the_lnet.ln_mt_state == LNET_MT_STATE_SHUTDOWN); + + /* perform cleanup tasks */ + lnet_rsp_tracker_clean(); + lnet_clean_local_ni_recoveryq(); + lnet_clean_peer_ni_recoveryq(); + lnet_clean_resendqs(); } void @@ -2159,8 +3832,8 @@ lnet_drop_message(struct lnet_ni *ni, int cpt, void *private, unsigned int nob, { lnet_net_lock(cpt); lnet_incr_stats(&ni->ni_stats, msg_type, LNET_STATS_TYPE_DROP); - the_lnet.ln_counters[cpt]->drop_count++; - the_lnet.ln_counters[cpt]->drop_length += nob; + the_lnet.ln_counters[cpt]->lct_common.lcc_drop_count++; + the_lnet.ln_counters[cpt]->lct_common.lcc_drop_length += nob; lnet_net_unlock(cpt); lnet_ni_recv(ni, private, NULL, 0, 0, 0, nob); @@ -2206,7 +3879,7 @@ lnet_parse_put(struct lnet_ni *ni, struct lnet_msg *msg) info.mi_rlength = hdr->payload_length; info.mi_roffset = hdr->msg.put.offset; info.mi_mbits = hdr->msg.put.match_bits; - info.mi_cpt = lnet_cpt_of_nid(msg->msg_rxpeer->lpni_nid, ni); + info.mi_cpt = lnet_cpt_of_nid(msg->msg_initiator, ni); msg->msg_rx_ready_delay = ni->ni_net->net_lnd->lnd_eager_recv == NULL; ready_delay = msg->msg_rx_ready_delay; @@ -2269,7 +3942,7 @@ lnet_parse_get(struct lnet_ni *ni, struct lnet_msg *msg, int rdma_get) info.mi_rlength = hdr->msg.get.sink_length; info.mi_roffset = hdr->msg.get.src_offset; info.mi_mbits = hdr->msg.get.match_bits; - info.mi_cpt = lnet_cpt_of_nid(msg->msg_rxpeer->lpni_nid, ni); + info.mi_cpt = lnet_cpt_of_nid(msg->msg_initiator, ni); rc = lnet_ptl_match_md(&info, msg); if (rc == LNET_MATCHMD_DROP) { @@ -2301,7 +3974,7 @@ lnet_parse_get(struct lnet_ni *ni, struct lnet_msg *msg, int rdma_get) lnet_ni_recv(ni, msg->msg_private, NULL, 0, 0, 0, 0); msg->msg_receiving = 0; - rc = lnet_send(ni->ni_nid, msg, LNET_NID_ANY); + rc = lnet_send(ni->ni_nid, msg, msg->msg_from); if (rc < 0) { /* didn't get as far as lnet_ni_send() */ CERROR("%s: Unable to send REPLY for GET from %s: %d\n", @@ -2317,13 +3990,13 @@ lnet_parse_get(struct lnet_ni *ni, struct lnet_msg *msg, int rdma_get) static int lnet_parse_reply(struct lnet_ni *ni, struct lnet_msg *msg) { - void *private = msg->msg_private; - struct lnet_hdr *hdr = &msg->msg_hdr; + void *private = msg->msg_private; + struct lnet_hdr *hdr = &msg->msg_hdr; struct lnet_process_id src = {0}; - struct lnet_libmd *md; - int rlength; - int mlength; - int cpt; + struct lnet_libmd *md; + unsigned int rlength; + unsigned int mlength; + int cpt; cpt = lnet_cpt_of_cookie(hdr->msg.reply.dst_wmd.wh_object_cookie); lnet_res_lock(cpt); @@ -2351,7 +4024,7 @@ lnet_parse_reply(struct lnet_ni *ni, struct lnet_msg *msg) LASSERT(md->md_offset == 0); rlength = hdr->payload_length; - mlength = MIN(rlength, (int)md->md_length); + mlength = min(rlength, md->md_length); if (mlength < rlength && (md->md_options & LNET_MD_TRUNCATE) == 0) { @@ -2384,10 +4057,10 @@ lnet_parse_reply(struct lnet_ni *ni, struct lnet_msg *msg) static int lnet_parse_ack(struct lnet_ni *ni, struct lnet_msg *msg) { - struct lnet_hdr *hdr = &msg->msg_hdr; + struct lnet_hdr *hdr = &msg->msg_hdr; struct lnet_process_id src = {0}; - struct lnet_libmd *md; - int cpt; + struct lnet_libmd *md; + int cpt; src.nid = hdr->src_nid; src.pid = hdr->src_pid; @@ -2572,16 +4245,17 @@ int lnet_parse(struct lnet_ni *ni, struct lnet_hdr *hdr, lnet_nid_t from_nid, void *private, int rdma_req) { - int rc = 0; - int cpt; - int for_me; - struct lnet_msg *msg; - lnet_pid_t dest_pid; - lnet_nid_t dest_nid; - lnet_nid_t src_nid; struct lnet_peer_ni *lpni; - __u32 payload_length; - __u32 type; + struct lnet_msg *msg; + __u32 payload_length; + lnet_pid_t dest_pid; + lnet_nid_t dest_nid; + lnet_nid_t src_nid; + bool push = false; + int for_me; + __u32 type; + int rc = 0; + int cpt; LASSERT (!in_interrupt ()); @@ -2636,16 +4310,22 @@ lnet_parse(struct lnet_ni *ni, struct lnet_hdr *hdr, lnet_nid_t from_nid, } if (the_lnet.ln_routing && - ni->ni_last_alive != ktime_get_real_seconds()) { - /* NB: so far here is the only place to set NI status to "up */ + ni->ni_net->net_last_alive != ktime_get_real_seconds()) { lnet_ni_lock(ni); - ni->ni_last_alive = ktime_get_real_seconds(); + spin_lock(&ni->ni_net->net_lock); + ni->ni_net->net_last_alive = ktime_get_real_seconds(); + spin_unlock(&ni->ni_net->net_lock); if (ni->ni_status != NULL && - ni->ni_status->ns_status == LNET_NI_STATUS_DOWN) + ni->ni_status->ns_status == LNET_NI_STATUS_DOWN) { ni->ni_status->ns_status = LNET_NI_STATUS_UP; + push = true; + } lnet_ni_unlock(ni); } + if (push) + lnet_push_update_to_peers(1); + /* Regard a bad destination NID as a protocol error. Senders should * know what they're doing; if they don't they're misconfigured, buggy * or malicious so we chop them off at the knees :) */ @@ -2703,14 +4383,68 @@ lnet_parse(struct lnet_ni *ni, struct lnet_hdr *hdr, lnet_nid_t from_nid, } if (!list_empty(&the_lnet.ln_drop_rules) && - lnet_drop_rule_match(hdr)) { - CDEBUG(D_NET, "%s, src %s, dst %s: Dropping %s to simulate" - "silent message loss\n", + lnet_drop_rule_match(hdr, ni->ni_nid, NULL)) { + CDEBUG(D_NET, + "%s, src %s, dst %s: Dropping %s to simulate silent message loss\n", libcfs_nid2str(from_nid), libcfs_nid2str(src_nid), libcfs_nid2str(dest_nid), lnet_msgtyp2str(type)); goto drop; } + if (lnet_drop_asym_route && for_me && + LNET_NIDNET(src_nid) != LNET_NIDNET(from_nid)) { + struct lnet_net *net; + struct lnet_remotenet *rnet; + bool found = true; + + /* we are dealing with a routed message, + * so see if route to reach src_nid goes through from_nid + */ + lnet_net_lock(cpt); + net = lnet_get_net_locked(LNET_NIDNET(ni->ni_nid)); + if (!net) { + lnet_net_unlock(cpt); + CERROR("net %s not found\n", + libcfs_net2str(LNET_NIDNET(ni->ni_nid))); + return -EPROTO; + } + + rnet = lnet_find_rnet_locked(LNET_NIDNET(src_nid)); + if (rnet) { + struct lnet_peer *gw = NULL; + struct lnet_peer_ni *lpni = NULL; + struct lnet_route *route; + + list_for_each_entry(route, &rnet->lrn_routes, lr_list) { + found = false; + gw = route->lr_gateway; + if (route->lr_lnet != net->net_id) + continue; + /* + * if the nid is one of the gateway's NIDs + * then this is a valid gateway + */ + while ((lpni = lnet_get_next_peer_ni_locked(gw, + NULL, lpni)) != NULL) { + if (lpni->lpni_nid == from_nid) { + found = true; + break; + } + } + } + } + lnet_net_unlock(cpt); + if (!found) { + /* we would not use from_nid to route a message to + * src_nid + * => asymmetric routing detected but forbidden + */ + CERROR("%s, src %s: Dropping asymmetrical route %s\n", + libcfs_nid2str(from_nid), + libcfs_nid2str(src_nid), lnet_msgtyp2str(type)); + goto drop; + } + } msg = lnet_msg_alloc(); if (msg == NULL) { @@ -2761,24 +4495,22 @@ lnet_parse(struct lnet_ni *ni, struct lnet_hdr *hdr, lnet_nid_t from_nid, return 0; goto drop; } + + if (the_lnet.ln_routing) + lpni->lpni_last_alive = ktime_get_seconds(); + msg->msg_rxpeer = lpni; msg->msg_rxni = ni; lnet_ni_addref_locked(ni, cpt); /* Multi-Rail: Primary NID of source. */ msg->msg_initiator = lnet_peer_primary_nid_locked(src_nid); - if (lnet_isrouter(msg->msg_rxpeer)) { - lnet_peer_set_alive(msg->msg_rxpeer); - if (avoid_asym_router_failure && - LNET_NIDNET(src_nid) != LNET_NIDNET(from_nid)) { - /* received a remote message from router, update - * remote NI status on this router. - * NB: multi-hop routed message will be ignored. - */ - lnet_router_ni_update_locked(msg->msg_rxpeer, - LNET_NIDNET(src_nid)); - } - } + /* + * mark the status of this lpni as UP since we received a message + * from it. The ping response reports back the ns_status which is + * marked on the remote as up or down and we cache it here. + */ + msg->msg_rxpeer->lpni_ns_status = LNET_NI_STATUS_UP; lnet_msg_commit(msg, cpt); @@ -2853,6 +4585,8 @@ lnet_drop_delayed_msg_list(struct list_head *head, char *reason) lnet_drop_message(msg->msg_rxni, msg->msg_rx_cpt, msg->msg_private, msg->msg_len, msg->msg_type); + + msg->msg_no_resend = true; /* * NB: message will not generate event because w/o attached MD, * but we still should give error code so lnet_msg_decommit() @@ -2895,6 +4629,50 @@ lnet_recv_delayed_msg_list(struct list_head *head) } } +static void +lnet_attach_rsp_tracker(struct lnet_rsp_tracker *rspt, int cpt, + struct lnet_libmd *md, struct lnet_handle_md mdh) +{ + s64 timeout_ns; + struct lnet_rsp_tracker *local_rspt; + + /* + * MD has a refcount taken by message so it's not going away. + * The MD however can be looked up. We need to secure the access + * to the md_rspt_ptr by taking the res_lock. + * The rspt can be accessed without protection up to when it gets + * added to the list. + */ + + lnet_res_lock(cpt); + local_rspt = md->md_rspt_ptr; + timeout_ns = lnet_transaction_timeout * NSEC_PER_SEC; + if (local_rspt != NULL) { + /* + * we already have an rspt attached to the md, so we'll + * update the deadline on that one. + */ + lnet_rspt_free(rspt, cpt); + } else { + /* new md */ + rspt->rspt_mdh = mdh; + rspt->rspt_cpt = cpt; + /* store the rspt so we can access it when we get the REPLY */ + md->md_rspt_ptr = rspt; + local_rspt = rspt; + } + local_rspt->rspt_deadline = ktime_add_ns(ktime_get(), timeout_ns); + + /* + * add to the list of tracked responses. It's added to tail of the + * list in order to expire all the older entries first. + */ + lnet_net_lock(cpt); + list_move_tail(&local_rspt->rspt_on_list, the_lnet.ln_mt_rstq[cpt]); + lnet_net_unlock(cpt); + lnet_res_unlock(cpt); +} + /** * Initiate an asynchronous PUT operation. * @@ -2945,10 +4723,11 @@ LNetPut(lnet_nid_t self, struct lnet_handle_md mdh, enum lnet_ack_req ack, __u64 match_bits, unsigned int offset, __u64 hdr_data) { - struct lnet_msg *msg; - struct lnet_libmd *md; - int cpt; - int rc; + struct lnet_msg *msg; + struct lnet_libmd *md; + int cpt; + int rc; + struct lnet_rsp_tracker *rspt = NULL; LASSERT(the_lnet.ln_refcount > 0); @@ -2968,6 +4747,17 @@ LNetPut(lnet_nid_t self, struct lnet_handle_md mdh, enum lnet_ack_req ack, msg->msg_vmflush = !!memory_pressure_get(); cpt = lnet_cpt_of_cookie(mdh.cookie); + + if (ack == LNET_ACK_REQ) { + rspt = lnet_rspt_alloc(cpt); + if (!rspt) { + CERROR("Dropping PUT to %s: ENOMEM on response tracker\n", + libcfs_id2str(target)); + return -ENOMEM; + } + INIT_LIST_HEAD(&rspt->rspt_on_list); + } + lnet_res_lock(cpt); md = lnet_handle2md(&mdh); @@ -2980,6 +4770,7 @@ LNetPut(lnet_nid_t self, struct lnet_handle_md mdh, enum lnet_ack_req ack, md->md_me->me_portal); lnet_res_unlock(cpt); + lnet_rspt_free(rspt, cpt); lnet_msg_free(msg); return -ENOENT; } @@ -3012,10 +4803,19 @@ LNetPut(lnet_nid_t self, struct lnet_handle_md mdh, enum lnet_ack_req ack, lnet_build_msg_event(msg, LNET_EVENT_SEND); - rc = lnet_send(self, msg, LNET_NID_ANY); + if (ack == LNET_ACK_REQ) + lnet_attach_rsp_tracker(rspt, cpt, md, mdh); + + if (CFS_FAIL_CHECK_ORSET(CFS_FAIL_PTLRPC_OST_BULK_CB2, + CFS_FAIL_ONCE)) + rc = -EIO; + else + rc = lnet_send(self, msg, LNET_NID_ANY); + if (rc != 0) { CNETERR("Error sending PUT to %s: %d\n", libcfs_id2str(target), rc); + msg->msg_no_resend = true; lnet_finalize(msg, rc); } @@ -3093,8 +4893,9 @@ lnet_create_reply_msg(struct lnet_ni *ni, struct lnet_msg *getmsg) lnet_net_lock(cpt); lnet_incr_stats(&ni->ni_stats, LNET_MSG_GET, LNET_STATS_TYPE_DROP); - the_lnet.ln_counters[cpt]->drop_count++; - the_lnet.ln_counters[cpt]->drop_length += getmd->md_length; + the_lnet.ln_counters[cpt]->lct_common.lcc_drop_count++; + the_lnet.ln_counters[cpt]->lct_common.lcc_drop_length += + getmd->md_length; lnet_net_unlock(cpt); if (msg != NULL) @@ -3145,12 +4946,13 @@ EXPORT_SYMBOL(lnet_set_reply_msg_len); int LNetGet(lnet_nid_t self, struct lnet_handle_md mdh, struct lnet_process_id target, unsigned int portal, - __u64 match_bits, unsigned int offset) + __u64 match_bits, unsigned int offset, bool recovery) { - struct lnet_msg *msg; - struct lnet_libmd *md; - int cpt; - int rc; + struct lnet_msg *msg; + struct lnet_libmd *md; + struct lnet_rsp_tracker *rspt; + int cpt; + int rc; LASSERT(the_lnet.ln_refcount > 0); @@ -3163,13 +4965,24 @@ LNetGet(lnet_nid_t self, struct lnet_handle_md mdh, } msg = lnet_msg_alloc(); - if (msg == NULL) { + if (!msg) { CERROR("Dropping GET to %s: ENOMEM on struct lnet_msg\n", libcfs_id2str(target)); return -ENOMEM; } cpt = lnet_cpt_of_cookie(mdh.cookie); + + rspt = lnet_rspt_alloc(cpt); + if (!rspt) { + CERROR("Dropping GET to %s: ENOMEM on response tracker\n", + libcfs_id2str(target)); + return -ENOMEM; + } + INIT_LIST_HEAD(&rspt->rspt_on_list); + + msg->msg_recovery = recovery; + lnet_res_lock(cpt); md = lnet_handle2md(&mdh); @@ -3184,6 +4997,7 @@ LNetGet(lnet_nid_t self, struct lnet_handle_md mdh, lnet_res_unlock(cpt); lnet_msg_free(msg); + lnet_rspt_free(rspt, cpt); return -ENOENT; } @@ -3208,10 +5022,13 @@ LNetGet(lnet_nid_t self, struct lnet_handle_md mdh, lnet_build_msg_event(msg, LNET_EVENT_SEND); + lnet_attach_rsp_tracker(rspt, cpt, md, mdh); + rc = lnet_send(self, msg, LNET_NID_ANY); if (rc < 0) { CNETERR("Error sending GET to %s: %d\n", libcfs_id2str(target), rc); + msg->msg_no_resend = true; lnet_finalize(msg, rc); } @@ -3275,9 +5092,9 @@ LNetDist(lnet_nid_t dstnid, lnet_nid_t *srcnidp, __u32 *orderp) * current net namespace. * If not, assign order above 0xffff0000, * to make this ni not a priority. */ - if (!net_eq(ni->ni_net_ns, current->nsproxy->net_ns)) - order += 0xffff0000; - + if (current->nsproxy && + !net_eq(ni->ni_net_ns, current->nsproxy->net_ns)) + order += 0xffff0000; if (srcnidp != NULL) *srcnidp = ni->ni_nid; if (orderp != NULL) @@ -3316,9 +5133,10 @@ LNetDist(lnet_nid_t dstnid, lnet_nid_t *srcnidp, __u32 *orderp) LASSERT(shortest != NULL); hops = shortest_hops; if (srcnidp != NULL) { - ni = lnet_get_next_ni_locked( - shortest->lr_gateway->lpni_net, - NULL); + struct lnet_net *net; + net = lnet_get_net_locked(shortest->lr_lnet); + LASSERT(net); + ni = lnet_get_next_ni_locked(net, NULL); *srcnidp = ni->ni_nid; } if (orderp != NULL)