4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2011, 2012, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * lnet/lnet/lib-move.c
38 * Data movement routines
41 #define DEBUG_SUBSYSTEM S_LNET
43 #include "../../include/linux/lnet/lib-lnet.h"
45 static int local_nid_dist_zero = 1;
46 module_param(local_nid_dist_zero, int, 0444);
47 MODULE_PARM_DESC(local_nid_dist_zero, "Reserved");
50 lnet_fail_nid(lnet_nid_t nid, unsigned int threshold)
54 struct list_head *next;
55 struct list_head cull;
57 LASSERT(the_lnet.ln_init);
59 /* NB: use lnet_net_lock(0) to serialize operations on test peers */
61 /* Adding a new entry */
62 LIBCFS_ALLOC(tp, sizeof(*tp));
67 tp->tp_threshold = threshold;
70 list_add_tail(&tp->tp_list, &the_lnet.ln_test_peers);
75 /* removing entries */
76 INIT_LIST_HEAD(&cull);
80 list_for_each_safe(el, next, &the_lnet.ln_test_peers) {
81 tp = list_entry(el, lnet_test_peer_t, tp_list);
83 if (tp->tp_threshold == 0 || /* needs culling anyway */
84 nid == LNET_NID_ANY || /* removing all entries */
85 tp->tp_nid == nid) { /* matched this one */
86 list_del(&tp->tp_list);
87 list_add(&tp->tp_list, &cull);
93 while (!list_empty(&cull)) {
94 tp = list_entry(cull.next, lnet_test_peer_t, tp_list);
96 list_del(&tp->tp_list);
97 LIBCFS_FREE(tp, sizeof(*tp));
103 fail_peer(lnet_nid_t nid, int outgoing)
105 lnet_test_peer_t *tp;
106 struct list_head *el;
107 struct list_head *next;
108 struct list_head cull;
111 INIT_LIST_HEAD(&cull);
113 /* NB: use lnet_net_lock(0) to serialize operations on test peers */
116 list_for_each_safe(el, next, &the_lnet.ln_test_peers) {
117 tp = list_entry(el, lnet_test_peer_t, tp_list);
119 if (tp->tp_threshold == 0) {
122 /* only cull zombies on outgoing tests,
123 * since we may be at interrupt priority on
124 * incoming messages. */
125 list_del(&tp->tp_list);
126 list_add(&tp->tp_list, &cull);
131 if (tp->tp_nid == LNET_NID_ANY || /* fail every peer */
132 nid == tp->tp_nid) { /* fail this peer */
135 if (tp->tp_threshold != LNET_MD_THRESH_INF) {
138 tp->tp_threshold == 0) {
140 list_del(&tp->tp_list);
141 list_add(&tp->tp_list, &cull);
150 while (!list_empty(&cull)) {
151 tp = list_entry(cull.next, lnet_test_peer_t, tp_list);
152 list_del(&tp->tp_list);
154 LIBCFS_FREE(tp, sizeof(*tp));
161 lnet_iov_nob(unsigned int niov, struct kvec *iov)
163 unsigned int nob = 0;
166 nob += (iov++)->iov_len;
170 EXPORT_SYMBOL(lnet_iov_nob);
173 lnet_copy_iov2iov(unsigned int ndiov, struct kvec *diov, unsigned int doffset,
174 unsigned int nsiov, struct kvec *siov, unsigned int soffset,
177 /* NB diov, siov are READ-ONLY */
178 unsigned int this_nob;
183 /* skip complete frags before 'doffset' */
185 while (doffset >= diov->iov_len) {
186 doffset -= diov->iov_len;
192 /* skip complete frags before 'soffset' */
194 while (soffset >= siov->iov_len) {
195 soffset -= siov->iov_len;
204 this_nob = min(diov->iov_len - doffset,
205 siov->iov_len - soffset);
206 this_nob = min(this_nob, nob);
208 memcpy((char *)diov->iov_base + doffset,
209 (char *)siov->iov_base + soffset, this_nob);
212 if (diov->iov_len > doffset + this_nob) {
220 if (siov->iov_len > soffset + this_nob) {
229 EXPORT_SYMBOL(lnet_copy_iov2iov);
232 lnet_extract_iov(int dst_niov, struct kvec *dst,
233 int src_niov, struct kvec *src,
234 unsigned int offset, unsigned int len)
236 /* Initialise 'dst' to the subset of 'src' starting at 'offset',
237 * for exactly 'len' bytes, and return the number of entries.
238 * NB not destructive to 'src' */
239 unsigned int frag_len;
242 if (len == 0) /* no data => */
243 return 0; /* no frags */
245 LASSERT(src_niov > 0);
246 while (offset >= src->iov_len) { /* skip initial frags */
247 offset -= src->iov_len;
250 LASSERT(src_niov > 0);
255 LASSERT(src_niov > 0);
256 LASSERT((int)niov <= dst_niov);
258 frag_len = src->iov_len - offset;
259 dst->iov_base = ((char *)src->iov_base) + offset;
261 if (len <= frag_len) {
266 dst->iov_len = frag_len;
276 EXPORT_SYMBOL(lnet_extract_iov);
280 lnet_kiov_nob(unsigned int niov, lnet_kiov_t *kiov)
282 unsigned int nob = 0;
285 nob += (kiov++)->kiov_len;
289 EXPORT_SYMBOL(lnet_kiov_nob);
292 lnet_copy_kiov2kiov(unsigned int ndiov, lnet_kiov_t *diov, unsigned int doffset,
293 unsigned int nsiov, lnet_kiov_t *siov, unsigned int soffset,
296 /* NB diov, siov are READ-ONLY */
297 unsigned int this_nob;
304 LASSERT(!in_interrupt());
307 while (doffset >= diov->kiov_len) {
308 doffset -= diov->kiov_len;
315 while (soffset >= siov->kiov_len) {
316 soffset -= siov->kiov_len;
325 this_nob = min(diov->kiov_len - doffset,
326 siov->kiov_len - soffset);
327 this_nob = min(this_nob, nob);
330 daddr = ((char *)kmap(diov->kiov_page)) +
331 diov->kiov_offset + doffset;
333 saddr = ((char *)kmap(siov->kiov_page)) +
334 siov->kiov_offset + soffset;
336 /* Vanishing risk of kmap deadlock when mapping 2 pages.
337 * However in practice at least one of the kiovs will be mapped
338 * kernel pages and the map/unmap will be NOOPs */
340 memcpy(daddr, saddr, this_nob);
343 if (diov->kiov_len > doffset + this_nob) {
347 kunmap(diov->kiov_page);
354 if (siov->kiov_len > soffset + this_nob) {
358 kunmap(siov->kiov_page);
367 kunmap(diov->kiov_page);
369 kunmap(siov->kiov_page);
371 EXPORT_SYMBOL(lnet_copy_kiov2kiov);
374 lnet_copy_kiov2iov(unsigned int niov, struct kvec *iov, unsigned int iovoffset,
375 unsigned int nkiov, lnet_kiov_t *kiov,
376 unsigned int kiovoffset, unsigned int nob)
378 /* NB iov, kiov are READ-ONLY */
379 unsigned int this_nob;
385 LASSERT(!in_interrupt());
388 while (iovoffset >= iov->iov_len) {
389 iovoffset -= iov->iov_len;
396 while (kiovoffset >= kiov->kiov_len) {
397 kiovoffset -= kiov->kiov_len;
406 this_nob = min(iov->iov_len - iovoffset,
407 (__kernel_size_t) kiov->kiov_len - kiovoffset);
408 this_nob = min(this_nob, nob);
411 addr = ((char *)kmap(kiov->kiov_page)) +
412 kiov->kiov_offset + kiovoffset;
414 memcpy((char *)iov->iov_base + iovoffset, addr, this_nob);
417 if (iov->iov_len > iovoffset + this_nob) {
418 iovoffset += this_nob;
425 if (kiov->kiov_len > kiovoffset + this_nob) {
427 kiovoffset += this_nob;
429 kunmap(kiov->kiov_page);
439 kunmap(kiov->kiov_page);
441 EXPORT_SYMBOL(lnet_copy_kiov2iov);
444 lnet_copy_iov2kiov(unsigned int nkiov, lnet_kiov_t *kiov,
445 unsigned int kiovoffset, unsigned int niov,
446 struct kvec *iov, unsigned int iovoffset,
449 /* NB kiov, iov are READ-ONLY */
450 unsigned int this_nob;
456 LASSERT(!in_interrupt());
459 while (kiovoffset >= kiov->kiov_len) {
460 kiovoffset -= kiov->kiov_len;
467 while (iovoffset >= iov->iov_len) {
468 iovoffset -= iov->iov_len;
477 this_nob = min((__kernel_size_t) kiov->kiov_len - kiovoffset,
478 iov->iov_len - iovoffset);
479 this_nob = min(this_nob, nob);
482 addr = ((char *)kmap(kiov->kiov_page)) +
483 kiov->kiov_offset + kiovoffset;
485 memcpy(addr, (char *)iov->iov_base + iovoffset, this_nob);
488 if (kiov->kiov_len > kiovoffset + this_nob) {
490 kiovoffset += this_nob;
492 kunmap(kiov->kiov_page);
499 if (iov->iov_len > iovoffset + this_nob) {
500 iovoffset += this_nob;
509 kunmap(kiov->kiov_page);
511 EXPORT_SYMBOL(lnet_copy_iov2kiov);
514 lnet_extract_kiov(int dst_niov, lnet_kiov_t *dst,
515 int src_niov, lnet_kiov_t *src,
516 unsigned int offset, unsigned int len)
518 /* Initialise 'dst' to the subset of 'src' starting at 'offset',
519 * for exactly 'len' bytes, and return the number of entries.
520 * NB not destructive to 'src' */
521 unsigned int frag_len;
524 if (len == 0) /* no data => */
525 return 0; /* no frags */
527 LASSERT(src_niov > 0);
528 while (offset >= src->kiov_len) { /* skip initial frags */
529 offset -= src->kiov_len;
532 LASSERT(src_niov > 0);
537 LASSERT(src_niov > 0);
538 LASSERT((int)niov <= dst_niov);
540 frag_len = src->kiov_len - offset;
541 dst->kiov_page = src->kiov_page;
542 dst->kiov_offset = src->kiov_offset + offset;
544 if (len <= frag_len) {
546 LASSERT(dst->kiov_offset + dst->kiov_len
551 dst->kiov_len = frag_len;
552 LASSERT(dst->kiov_offset + dst->kiov_len <= PAGE_CACHE_SIZE);
562 EXPORT_SYMBOL(lnet_extract_kiov);
565 lnet_ni_recv(lnet_ni_t *ni, void *private, lnet_msg_t *msg, int delayed,
566 unsigned int offset, unsigned int mlen, unsigned int rlen)
568 unsigned int niov = 0;
569 struct kvec *iov = NULL;
570 lnet_kiov_t *kiov = NULL;
573 LASSERT(!in_interrupt());
574 LASSERT(mlen == 0 || msg != NULL);
577 LASSERT(msg->msg_receiving);
578 LASSERT(!msg->msg_sending);
579 LASSERT(rlen == msg->msg_len);
580 LASSERT(mlen <= msg->msg_len);
581 LASSERT(msg->msg_offset == offset);
582 LASSERT(msg->msg_wanted == mlen);
584 msg->msg_receiving = 0;
587 niov = msg->msg_niov;
589 kiov = msg->msg_kiov;
592 LASSERT((iov == NULL) != (kiov == NULL));
596 rc = (ni->ni_lnd->lnd_recv)(ni, private, msg, delayed,
597 niov, iov, kiov, offset, mlen, rlen);
599 lnet_finalize(ni, msg, rc);
603 lnet_setpayloadbuffer(lnet_msg_t *msg)
605 lnet_libmd_t *md = msg->msg_md;
607 LASSERT(msg->msg_len > 0);
608 LASSERT(!msg->msg_routing);
610 LASSERT(msg->msg_niov == 0);
611 LASSERT(msg->msg_iov == NULL);
612 LASSERT(msg->msg_kiov == NULL);
614 msg->msg_niov = md->md_niov;
615 if ((md->md_options & LNET_MD_KIOV) != 0)
616 msg->msg_kiov = md->md_iov.kiov;
618 msg->msg_iov = md->md_iov.iov;
622 lnet_prep_send(lnet_msg_t *msg, int type, lnet_process_id_t target,
623 unsigned int offset, unsigned int len)
625 msg->msg_type = type;
626 msg->msg_target = target;
628 msg->msg_offset = offset;
631 lnet_setpayloadbuffer(msg);
633 memset(&msg->msg_hdr, 0, sizeof(msg->msg_hdr));
634 msg->msg_hdr.type = cpu_to_le32(type);
635 msg->msg_hdr.dest_nid = cpu_to_le64(target.nid);
636 msg->msg_hdr.dest_pid = cpu_to_le32(target.pid);
637 /* src_nid will be set later */
638 msg->msg_hdr.src_pid = cpu_to_le32(the_lnet.ln_pid);
639 msg->msg_hdr.payload_length = cpu_to_le32(len);
643 lnet_ni_send(lnet_ni_t *ni, lnet_msg_t *msg)
645 void *priv = msg->msg_private;
648 LASSERT(!in_interrupt());
649 LASSERT(LNET_NETTYP(LNET_NIDNET(ni->ni_nid)) == LOLND ||
650 (msg->msg_txcredit && msg->msg_peertxcredit));
652 rc = (ni->ni_lnd->lnd_send)(ni, priv, msg);
654 lnet_finalize(ni, msg, rc);
658 lnet_ni_eager_recv(lnet_ni_t *ni, lnet_msg_t *msg)
662 LASSERT(!msg->msg_sending);
663 LASSERT(msg->msg_receiving);
664 LASSERT(!msg->msg_rx_ready_delay);
665 LASSERT(ni->ni_lnd->lnd_eager_recv != NULL);
667 msg->msg_rx_ready_delay = 1;
668 rc = (ni->ni_lnd->lnd_eager_recv)(ni, msg->msg_private, msg,
671 CERROR("recv from %s / send to %s aborted: eager_recv failed %d\n",
672 libcfs_nid2str(msg->msg_rxpeer->lp_nid),
673 libcfs_id2str(msg->msg_target), rc);
674 LASSERT(rc < 0); /* required by my callers */
680 /* NB: caller shall hold a ref on 'lp' as I'd drop lnet_net_lock */
682 lnet_ni_query_locked(lnet_ni_t *ni, lnet_peer_t *lp)
684 unsigned long last_alive = 0;
686 LASSERT(lnet_peer_aliveness_enabled(lp));
687 LASSERT(ni->ni_lnd->lnd_query != NULL);
689 lnet_net_unlock(lp->lp_cpt);
690 (ni->ni_lnd->lnd_query)(ni, lp->lp_nid, &last_alive);
691 lnet_net_lock(lp->lp_cpt);
693 lp->lp_last_query = cfs_time_current();
695 if (last_alive != 0) /* NI has updated timestamp */
696 lp->lp_last_alive = last_alive;
699 /* NB: always called with lnet_net_lock held */
701 lnet_peer_is_alive(lnet_peer_t *lp, unsigned long now)
704 unsigned long deadline;
706 LASSERT(lnet_peer_aliveness_enabled(lp));
708 /* Trust lnet_notify() if it has more recent aliveness news, but
709 * ignore the initial assumed death (see lnet_peers_start_down()).
711 if (!lp->lp_alive && lp->lp_alive_count > 0 &&
712 cfs_time_aftereq(lp->lp_timestamp, lp->lp_last_alive))
715 deadline = cfs_time_add(lp->lp_last_alive,
716 cfs_time_seconds(lp->lp_ni->ni_peertimeout));
717 alive = cfs_time_after(deadline, now);
719 /* Update obsolete lp_alive except for routers assumed to be dead
720 * initially, because router checker would update aliveness in this
721 * case, and moreover lp_last_alive at peer creation is assumed.
723 if (alive && !lp->lp_alive &&
724 !(lnet_isrouter(lp) && lp->lp_alive_count == 0))
725 lnet_notify_locked(lp, 0, 1, lp->lp_last_alive);
731 /* NB: returns 1 when alive, 0 when dead, negative when error;
732 * may drop the lnet_net_lock */
734 lnet_peer_alive_locked(lnet_peer_t *lp)
736 unsigned long now = cfs_time_current();
738 if (!lnet_peer_aliveness_enabled(lp))
741 if (lnet_peer_is_alive(lp, now))
744 /* Peer appears dead, but we should avoid frequent NI queries (at
745 * most once per lnet_queryinterval seconds). */
746 if (lp->lp_last_query != 0) {
747 static const int lnet_queryinterval = 1;
749 unsigned long next_query =
750 cfs_time_add(lp->lp_last_query,
751 cfs_time_seconds(lnet_queryinterval));
753 if (time_before(now, next_query)) {
755 CWARN("Unexpected aliveness of peer %s: %d < %d (%d/%d)\n",
756 libcfs_nid2str(lp->lp_nid),
757 (int)now, (int)next_query,
759 lp->lp_ni->ni_peertimeout);
764 /* query NI for latest aliveness news */
765 lnet_ni_query_locked(lp->lp_ni, lp);
767 if (lnet_peer_is_alive(lp, now))
770 lnet_notify_locked(lp, 0, 0, lp->lp_last_alive);
775 * \param msg The message to be sent.
776 * \param do_send True if lnet_ni_send() should be called in this function.
777 * lnet_send() is going to lnet_net_unlock immediately after this, so
778 * it sets do_send FALSE and I don't do the unlock/send/lock bit.
780 * \retval 0 If \a msg sent or OK to send.
781 * \retval EAGAIN If \a msg blocked for credit.
782 * \retval EHOSTUNREACH If the next hop of the message appears dead.
783 * \retval ECANCELED If the MD of the message has been unlinked.
786 lnet_post_send_locked(lnet_msg_t *msg, int do_send)
788 lnet_peer_t *lp = msg->msg_txpeer;
789 lnet_ni_t *ni = lp->lp_ni;
790 int cpt = msg->msg_tx_cpt;
791 struct lnet_tx_queue *tq = ni->ni_tx_queues[cpt];
793 /* non-lnet_send() callers have checked before */
794 LASSERT(!do_send || msg->msg_tx_delayed);
795 LASSERT(!msg->msg_receiving);
796 LASSERT(msg->msg_tx_committed);
798 /* NB 'lp' is always the next hop */
799 if ((msg->msg_target.pid & LNET_PID_USERFLAG) == 0 &&
800 lnet_peer_alive_locked(lp) == 0) {
801 the_lnet.ln_counters[cpt]->drop_count++;
802 the_lnet.ln_counters[cpt]->drop_length += msg->msg_len;
803 lnet_net_unlock(cpt);
805 CNETERR("Dropping message for %s: peer not alive\n",
806 libcfs_id2str(msg->msg_target));
808 lnet_finalize(ni, msg, -EHOSTUNREACH);
814 if (msg->msg_md != NULL &&
815 (msg->msg_md->md_flags & LNET_MD_FLAG_ABORTED) != 0) {
816 lnet_net_unlock(cpt);
818 CNETERR("Aborting message for %s: LNetM[DE]Unlink() already called on the MD/ME.\n",
819 libcfs_id2str(msg->msg_target));
821 lnet_finalize(ni, msg, -ECANCELED);
827 if (!msg->msg_peertxcredit) {
828 LASSERT((lp->lp_txcredits < 0) ==
829 !list_empty(&lp->lp_txq));
831 msg->msg_peertxcredit = 1;
832 lp->lp_txqnob += msg->msg_len + sizeof(lnet_hdr_t);
835 if (lp->lp_txcredits < lp->lp_mintxcredits)
836 lp->lp_mintxcredits = lp->lp_txcredits;
838 if (lp->lp_txcredits < 0) {
839 msg->msg_tx_delayed = 1;
840 list_add_tail(&msg->msg_list, &lp->lp_txq);
845 if (!msg->msg_txcredit) {
846 LASSERT((tq->tq_credits < 0) ==
847 !list_empty(&tq->tq_delayed));
849 msg->msg_txcredit = 1;
852 if (tq->tq_credits < tq->tq_credits_min)
853 tq->tq_credits_min = tq->tq_credits;
855 if (tq->tq_credits < 0) {
856 msg->msg_tx_delayed = 1;
857 list_add_tail(&msg->msg_list, &tq->tq_delayed);
863 lnet_net_unlock(cpt);
864 lnet_ni_send(ni, msg);
871 static lnet_rtrbufpool_t *
872 lnet_msg2bufpool(lnet_msg_t *msg)
874 lnet_rtrbufpool_t *rbp;
877 LASSERT(msg->msg_rx_committed);
879 cpt = msg->msg_rx_cpt;
880 rbp = &the_lnet.ln_rtrpools[cpt][0];
882 LASSERT(msg->msg_len <= LNET_MTU);
883 while (msg->msg_len > (unsigned int)rbp->rbp_npages * PAGE_CACHE_SIZE) {
885 LASSERT(rbp < &the_lnet.ln_rtrpools[cpt][LNET_NRBPOOLS]);
892 lnet_post_routed_recv_locked(lnet_msg_t *msg, int do_recv)
894 /* lnet_parse is going to lnet_net_unlock immediately after this, so it
895 * sets do_recv FALSE and I don't do the unlock/send/lock bit. I
896 * return EAGAIN if msg blocked and 0 if received or OK to receive */
897 lnet_peer_t *lp = msg->msg_rxpeer;
898 lnet_rtrbufpool_t *rbp;
901 LASSERT(msg->msg_iov == NULL);
902 LASSERT(msg->msg_kiov == NULL);
903 LASSERT(msg->msg_niov == 0);
904 LASSERT(msg->msg_routing);
905 LASSERT(msg->msg_receiving);
906 LASSERT(!msg->msg_sending);
908 /* non-lnet_parse callers only receive delayed messages */
909 LASSERT(!do_recv || msg->msg_rx_delayed);
911 if (!msg->msg_peerrtrcredit) {
912 LASSERT((lp->lp_rtrcredits < 0) ==
913 !list_empty(&lp->lp_rtrq));
915 msg->msg_peerrtrcredit = 1;
917 if (lp->lp_rtrcredits < lp->lp_minrtrcredits)
918 lp->lp_minrtrcredits = lp->lp_rtrcredits;
920 if (lp->lp_rtrcredits < 0) {
921 /* must have checked eager_recv before here */
922 LASSERT(msg->msg_rx_ready_delay);
923 msg->msg_rx_delayed = 1;
924 list_add_tail(&msg->msg_list, &lp->lp_rtrq);
929 rbp = lnet_msg2bufpool(msg);
931 if (!msg->msg_rtrcredit) {
932 LASSERT((rbp->rbp_credits < 0) ==
933 !list_empty(&rbp->rbp_msgs));
935 msg->msg_rtrcredit = 1;
937 if (rbp->rbp_credits < rbp->rbp_mincredits)
938 rbp->rbp_mincredits = rbp->rbp_credits;
940 if (rbp->rbp_credits < 0) {
941 /* must have checked eager_recv before here */
942 LASSERT(msg->msg_rx_ready_delay);
943 msg->msg_rx_delayed = 1;
944 list_add_tail(&msg->msg_list, &rbp->rbp_msgs);
949 LASSERT(!list_empty(&rbp->rbp_bufs));
950 rb = list_entry(rbp->rbp_bufs.next, lnet_rtrbuf_t, rb_list);
951 list_del(&rb->rb_list);
953 msg->msg_niov = rbp->rbp_npages;
954 msg->msg_kiov = &rb->rb_kiov[0];
957 int cpt = msg->msg_rx_cpt;
959 lnet_net_unlock(cpt);
960 lnet_ni_recv(lp->lp_ni, msg->msg_private, msg, 1,
961 0, msg->msg_len, msg->msg_len);
968 lnet_return_tx_credits_locked(lnet_msg_t *msg)
970 lnet_peer_t *txpeer = msg->msg_txpeer;
973 if (msg->msg_txcredit) {
974 struct lnet_ni *ni = txpeer->lp_ni;
975 struct lnet_tx_queue *tq = ni->ni_tx_queues[msg->msg_tx_cpt];
977 /* give back NI txcredits */
978 msg->msg_txcredit = 0;
980 LASSERT((tq->tq_credits < 0) ==
981 !list_empty(&tq->tq_delayed));
984 if (tq->tq_credits <= 0) {
985 msg2 = list_entry(tq->tq_delayed.next,
986 lnet_msg_t, msg_list);
987 list_del(&msg2->msg_list);
989 LASSERT(msg2->msg_txpeer->lp_ni == ni);
990 LASSERT(msg2->msg_tx_delayed);
992 (void) lnet_post_send_locked(msg2, 1);
996 if (msg->msg_peertxcredit) {
997 /* give back peer txcredits */
998 msg->msg_peertxcredit = 0;
1000 LASSERT((txpeer->lp_txcredits < 0) ==
1001 !list_empty(&txpeer->lp_txq));
1003 txpeer->lp_txqnob -= msg->msg_len + sizeof(lnet_hdr_t);
1004 LASSERT(txpeer->lp_txqnob >= 0);
1006 txpeer->lp_txcredits++;
1007 if (txpeer->lp_txcredits <= 0) {
1008 msg2 = list_entry(txpeer->lp_txq.next,
1009 lnet_msg_t, msg_list);
1010 list_del(&msg2->msg_list);
1012 LASSERT(msg2->msg_txpeer == txpeer);
1013 LASSERT(msg2->msg_tx_delayed);
1015 (void) lnet_post_send_locked(msg2, 1);
1019 if (txpeer != NULL) {
1020 msg->msg_txpeer = NULL;
1021 lnet_peer_decref_locked(txpeer);
1026 lnet_return_rx_credits_locked(lnet_msg_t *msg)
1028 lnet_peer_t *rxpeer = msg->msg_rxpeer;
1031 if (msg->msg_rtrcredit) {
1032 /* give back global router credits */
1034 lnet_rtrbufpool_t *rbp;
1036 /* NB If a msg ever blocks for a buffer in rbp_msgs, it stays
1037 * there until it gets one allocated, or aborts the wait
1039 LASSERT(msg->msg_kiov != NULL);
1041 rb = list_entry(msg->msg_kiov, lnet_rtrbuf_t, rb_kiov[0]);
1043 LASSERT(rbp == lnet_msg2bufpool(msg));
1045 msg->msg_kiov = NULL;
1046 msg->msg_rtrcredit = 0;
1048 LASSERT((rbp->rbp_credits < 0) ==
1049 !list_empty(&rbp->rbp_msgs));
1050 LASSERT((rbp->rbp_credits > 0) ==
1051 !list_empty(&rbp->rbp_bufs));
1053 list_add(&rb->rb_list, &rbp->rbp_bufs);
1055 if (rbp->rbp_credits <= 0) {
1056 msg2 = list_entry(rbp->rbp_msgs.next,
1057 lnet_msg_t, msg_list);
1058 list_del(&msg2->msg_list);
1060 (void) lnet_post_routed_recv_locked(msg2, 1);
1064 if (msg->msg_peerrtrcredit) {
1065 /* give back peer router credits */
1066 msg->msg_peerrtrcredit = 0;
1068 LASSERT((rxpeer->lp_rtrcredits < 0) ==
1069 !list_empty(&rxpeer->lp_rtrq));
1071 rxpeer->lp_rtrcredits++;
1072 if (rxpeer->lp_rtrcredits <= 0) {
1073 msg2 = list_entry(rxpeer->lp_rtrq.next,
1074 lnet_msg_t, msg_list);
1075 list_del(&msg2->msg_list);
1077 (void) lnet_post_routed_recv_locked(msg2, 1);
1080 if (rxpeer != NULL) {
1081 msg->msg_rxpeer = NULL;
1082 lnet_peer_decref_locked(rxpeer);
1087 lnet_compare_routes(lnet_route_t *r1, lnet_route_t *r2)
1089 lnet_peer_t *p1 = r1->lr_gateway;
1090 lnet_peer_t *p2 = r2->lr_gateway;
1092 if (r1->lr_priority < r2->lr_priority)
1095 if (r1->lr_priority > r2->lr_priority)
1098 if (r1->lr_hops < r2->lr_hops)
1101 if (r1->lr_hops > r2->lr_hops)
1104 if (p1->lp_txqnob < p2->lp_txqnob)
1107 if (p1->lp_txqnob > p2->lp_txqnob)
1110 if (p1->lp_txcredits > p2->lp_txcredits)
1113 if (p1->lp_txcredits < p2->lp_txcredits)
1116 if (r1->lr_seq - r2->lr_seq <= 0)
1122 static lnet_peer_t *
1123 lnet_find_route_locked(lnet_ni_t *ni, lnet_nid_t target, lnet_nid_t rtr_nid)
1125 lnet_remotenet_t *rnet;
1127 lnet_route_t *rtr_best;
1128 lnet_route_t *rtr_last;
1129 struct lnet_peer *lp_best;
1130 struct lnet_peer *lp;
1133 /* If @rtr_nid is not LNET_NID_ANY, return the gateway with
1134 * rtr_nid nid, otherwise find the best gateway I can use */
1136 rnet = lnet_find_net_locked(LNET_NIDNET(target));
1141 rtr_best = rtr_last = NULL;
1142 list_for_each_entry(rtr, &rnet->lrn_routes, lr_list) {
1143 lp = rtr->lr_gateway;
1145 if (!lp->lp_alive || /* gateway is down */
1146 ((lp->lp_ping_feats & LNET_PING_FEAT_NI_STATUS) != 0 &&
1147 rtr->lr_downis != 0)) /* NI to target is down */
1150 if (ni != NULL && lp->lp_ni != ni)
1153 if (lp->lp_nid == rtr_nid) /* it's pre-determined router */
1156 if (lp_best == NULL) {
1157 rtr_best = rtr_last = rtr;
1162 /* no protection on below fields, but it's harmless */
1163 if (rtr_last->lr_seq - rtr->lr_seq < 0)
1166 rc = lnet_compare_routes(rtr, rtr_best);
1174 /* set sequence number on the best router to the latest sequence + 1
1175 * so we can round-robin all routers, it's race and inaccurate but
1176 * harmless and functional */
1177 if (rtr_best != NULL)
1178 rtr_best->lr_seq = rtr_last->lr_seq + 1;
1183 lnet_send(lnet_nid_t src_nid, lnet_msg_t *msg, lnet_nid_t rtr_nid)
1185 lnet_nid_t dst_nid = msg->msg_target.nid;
1186 struct lnet_ni *src_ni;
1187 struct lnet_ni *local_ni;
1188 struct lnet_peer *lp;
1193 /* NB: rtr_nid is set to LNET_NID_ANY for all current use-cases,
1194 * but we might want to use pre-determined router for ACK/REPLY
1196 /* NB: ni != NULL == interface pre-determined (ACK/REPLY) */
1197 LASSERT(msg->msg_txpeer == NULL);
1198 LASSERT(!msg->msg_sending);
1199 LASSERT(!msg->msg_target_is_router);
1200 LASSERT(!msg->msg_receiving);
1202 msg->msg_sending = 1;
1204 LASSERT(!msg->msg_tx_committed);
1205 cpt = lnet_cpt_of_nid(rtr_nid == LNET_NID_ANY ? dst_nid : rtr_nid);
1209 if (the_lnet.ln_shutdown) {
1210 lnet_net_unlock(cpt);
1214 if (src_nid == LNET_NID_ANY) {
1217 src_ni = lnet_nid2ni_locked(src_nid, cpt);
1218 if (src_ni == NULL) {
1219 lnet_net_unlock(cpt);
1220 LCONSOLE_WARN("Can't send to %s: src %s is not a local nid\n",
1221 libcfs_nid2str(dst_nid),
1222 libcfs_nid2str(src_nid));
1225 LASSERT(!msg->msg_routing);
1228 /* Is this for someone on a local network? */
1229 local_ni = lnet_net2ni_locked(LNET_NIDNET(dst_nid), cpt);
1231 if (local_ni != NULL) {
1232 if (src_ni == NULL) {
1234 src_nid = src_ni->ni_nid;
1235 } else if (src_ni == local_ni) {
1236 lnet_ni_decref_locked(local_ni, cpt);
1238 lnet_ni_decref_locked(local_ni, cpt);
1239 lnet_ni_decref_locked(src_ni, cpt);
1240 lnet_net_unlock(cpt);
1241 LCONSOLE_WARN("No route to %s via from %s\n",
1242 libcfs_nid2str(dst_nid),
1243 libcfs_nid2str(src_nid));
1247 LASSERT(src_nid != LNET_NID_ANY);
1248 lnet_msg_commit(msg, cpt);
1250 if (!msg->msg_routing)
1251 msg->msg_hdr.src_nid = cpu_to_le64(src_nid);
1253 if (src_ni == the_lnet.ln_loni) {
1254 /* No send credit hassles with LOLND */
1255 lnet_net_unlock(cpt);
1256 lnet_ni_send(src_ni, msg);
1259 lnet_ni_decref_locked(src_ni, cpt);
1260 lnet_net_unlock(cpt);
1264 rc = lnet_nid2peer_locked(&lp, dst_nid, cpt);
1265 /* lp has ref on src_ni; lose mine */
1266 lnet_ni_decref_locked(src_ni, cpt);
1268 lnet_net_unlock(cpt);
1269 LCONSOLE_WARN("Error %d finding peer %s\n", rc,
1270 libcfs_nid2str(dst_nid));
1271 /* ENOMEM or shutting down */
1274 LASSERT(lp->lp_ni == src_ni);
1276 /* sending to a remote network */
1277 lp = lnet_find_route_locked(src_ni, dst_nid, rtr_nid);
1280 lnet_ni_decref_locked(src_ni, cpt);
1281 lnet_net_unlock(cpt);
1283 LCONSOLE_WARN("No route to %s via %s (all routers down)\n",
1284 libcfs_id2str(msg->msg_target),
1285 libcfs_nid2str(src_nid));
1286 return -EHOSTUNREACH;
1289 /* rtr_nid is LNET_NID_ANY or NID of pre-determined router,
1290 * it's possible that rtr_nid isn't LNET_NID_ANY and lp isn't
1291 * pre-determined router, this can happen if router table
1292 * was changed when we release the lock */
1293 if (rtr_nid != lp->lp_nid) {
1294 cpt2 = lnet_cpt_of_nid_locked(lp->lp_nid);
1297 lnet_ni_decref_locked(src_ni, cpt);
1298 lnet_net_unlock(cpt);
1300 rtr_nid = lp->lp_nid;
1306 CDEBUG(D_NET, "Best route to %s via %s for %s %d\n",
1307 libcfs_nid2str(dst_nid), libcfs_nid2str(lp->lp_nid),
1308 lnet_msgtyp2str(msg->msg_type), msg->msg_len);
1310 if (src_ni == NULL) {
1312 src_nid = src_ni->ni_nid;
1314 LASSERT(src_ni == lp->lp_ni);
1315 lnet_ni_decref_locked(src_ni, cpt);
1318 lnet_peer_addref_locked(lp);
1320 LASSERT(src_nid != LNET_NID_ANY);
1321 lnet_msg_commit(msg, cpt);
1323 if (!msg->msg_routing) {
1324 /* I'm the source and now I know which NI to send on */
1325 msg->msg_hdr.src_nid = cpu_to_le64(src_nid);
1328 msg->msg_target_is_router = 1;
1329 msg->msg_target.nid = lp->lp_nid;
1330 msg->msg_target.pid = LUSTRE_SRV_LNET_PID;
1333 /* 'lp' is our best choice of peer */
1335 LASSERT(!msg->msg_peertxcredit);
1336 LASSERT(!msg->msg_txcredit);
1337 LASSERT(msg->msg_txpeer == NULL);
1339 msg->msg_txpeer = lp; /* msg takes my ref on lp */
1341 rc = lnet_post_send_locked(msg, 0);
1342 lnet_net_unlock(cpt);
1344 if (rc == EHOSTUNREACH || rc == ECANCELED)
1348 lnet_ni_send(src_ni, msg);
1350 return 0; /* rc == 0 or EAGAIN */
1354 lnet_drop_message(lnet_ni_t *ni, int cpt, void *private, unsigned int nob)
1357 the_lnet.ln_counters[cpt]->drop_count++;
1358 the_lnet.ln_counters[cpt]->drop_length += nob;
1359 lnet_net_unlock(cpt);
1361 lnet_ni_recv(ni, private, NULL, 0, 0, 0, nob);
1365 lnet_recv_put(lnet_ni_t *ni, lnet_msg_t *msg)
1367 lnet_hdr_t *hdr = &msg->msg_hdr;
1369 if (msg->msg_wanted != 0)
1370 lnet_setpayloadbuffer(msg);
1372 lnet_build_msg_event(msg, LNET_EVENT_PUT);
1374 /* Must I ACK? If so I'll grab the ack_wmd out of the header and put
1375 * it back into the ACK during lnet_finalize() */
1376 msg->msg_ack = (!lnet_is_wire_handle_none(&hdr->msg.put.ack_wmd) &&
1377 (msg->msg_md->md_options & LNET_MD_ACK_DISABLE) == 0);
1379 lnet_ni_recv(ni, msg->msg_private, msg, msg->msg_rx_delayed,
1380 msg->msg_offset, msg->msg_wanted, hdr->payload_length);
1384 lnet_parse_put(lnet_ni_t *ni, lnet_msg_t *msg)
1386 lnet_hdr_t *hdr = &msg->msg_hdr;
1387 struct lnet_match_info info;
1390 /* Convert put fields to host byte order */
1391 hdr->msg.put.match_bits = le64_to_cpu(hdr->msg.put.match_bits);
1392 hdr->msg.put.ptl_index = le32_to_cpu(hdr->msg.put.ptl_index);
1393 hdr->msg.put.offset = le32_to_cpu(hdr->msg.put.offset);
1395 info.mi_id.nid = hdr->src_nid;
1396 info.mi_id.pid = hdr->src_pid;
1397 info.mi_opc = LNET_MD_OP_PUT;
1398 info.mi_portal = hdr->msg.put.ptl_index;
1399 info.mi_rlength = hdr->payload_length;
1400 info.mi_roffset = hdr->msg.put.offset;
1401 info.mi_mbits = hdr->msg.put.match_bits;
1403 msg->msg_rx_ready_delay = ni->ni_lnd->lnd_eager_recv == NULL;
1406 rc = lnet_ptl_match_md(&info, msg);
1411 case LNET_MATCHMD_OK:
1412 lnet_recv_put(ni, msg);
1415 case LNET_MATCHMD_NONE:
1416 if (msg->msg_rx_delayed) /* attached on delayed list */
1419 rc = lnet_ni_eager_recv(ni, msg);
1424 case LNET_MATCHMD_DROP:
1425 CNETERR("Dropping PUT from %s portal %d match %llu offset %d length %d: %d\n",
1426 libcfs_id2str(info.mi_id), info.mi_portal,
1427 info.mi_mbits, info.mi_roffset, info.mi_rlength, rc);
1429 return ENOENT; /* +ve: OK but no match */
1434 lnet_parse_get(lnet_ni_t *ni, lnet_msg_t *msg, int rdma_get)
1436 struct lnet_match_info info;
1437 lnet_hdr_t *hdr = &msg->msg_hdr;
1438 lnet_handle_wire_t reply_wmd;
1441 /* Convert get fields to host byte order */
1442 hdr->msg.get.match_bits = le64_to_cpu(hdr->msg.get.match_bits);
1443 hdr->msg.get.ptl_index = le32_to_cpu(hdr->msg.get.ptl_index);
1444 hdr->msg.get.sink_length = le32_to_cpu(hdr->msg.get.sink_length);
1445 hdr->msg.get.src_offset = le32_to_cpu(hdr->msg.get.src_offset);
1447 info.mi_id.nid = hdr->src_nid;
1448 info.mi_id.pid = hdr->src_pid;
1449 info.mi_opc = LNET_MD_OP_GET;
1450 info.mi_portal = hdr->msg.get.ptl_index;
1451 info.mi_rlength = hdr->msg.get.sink_length;
1452 info.mi_roffset = hdr->msg.get.src_offset;
1453 info.mi_mbits = hdr->msg.get.match_bits;
1455 rc = lnet_ptl_match_md(&info, msg);
1456 if (rc == LNET_MATCHMD_DROP) {
1457 CNETERR("Dropping GET from %s portal %d match %llu offset %d length %d\n",
1458 libcfs_id2str(info.mi_id), info.mi_portal,
1459 info.mi_mbits, info.mi_roffset, info.mi_rlength);
1460 return ENOENT; /* +ve: OK but no match */
1463 LASSERT(rc == LNET_MATCHMD_OK);
1465 lnet_build_msg_event(msg, LNET_EVENT_GET);
1467 reply_wmd = hdr->msg.get.return_wmd;
1469 lnet_prep_send(msg, LNET_MSG_REPLY, info.mi_id,
1470 msg->msg_offset, msg->msg_wanted);
1472 msg->msg_hdr.msg.reply.dst_wmd = reply_wmd;
1475 /* The LND completes the REPLY from her recv procedure */
1476 lnet_ni_recv(ni, msg->msg_private, msg, 0,
1477 msg->msg_offset, msg->msg_len, msg->msg_len);
1481 lnet_ni_recv(ni, msg->msg_private, NULL, 0, 0, 0, 0);
1482 msg->msg_receiving = 0;
1484 rc = lnet_send(ni->ni_nid, msg, LNET_NID_ANY);
1486 /* didn't get as far as lnet_ni_send() */
1487 CERROR("%s: Unable to send REPLY for GET from %s: %d\n",
1488 libcfs_nid2str(ni->ni_nid),
1489 libcfs_id2str(info.mi_id), rc);
1491 lnet_finalize(ni, msg, rc);
1498 lnet_parse_reply(lnet_ni_t *ni, lnet_msg_t *msg)
1500 void *private = msg->msg_private;
1501 lnet_hdr_t *hdr = &msg->msg_hdr;
1502 lnet_process_id_t src = {0};
1508 cpt = lnet_cpt_of_cookie(hdr->msg.reply.dst_wmd.wh_object_cookie);
1511 src.nid = hdr->src_nid;
1512 src.pid = hdr->src_pid;
1514 /* NB handles only looked up by creator (no flips) */
1515 md = lnet_wire_handle2md(&hdr->msg.reply.dst_wmd);
1516 if (md == NULL || md->md_threshold == 0 || md->md_me != NULL) {
1517 CNETERR("%s: Dropping REPLY from %s for %s MD %#llx.%#llx\n",
1518 libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1519 (md == NULL) ? "invalid" : "inactive",
1520 hdr->msg.reply.dst_wmd.wh_interface_cookie,
1521 hdr->msg.reply.dst_wmd.wh_object_cookie);
1522 if (md != NULL && md->md_me != NULL)
1523 CERROR("REPLY MD also attached to portal %d\n",
1524 md->md_me->me_portal);
1526 lnet_res_unlock(cpt);
1527 return ENOENT; /* +ve: OK but no match */
1530 LASSERT(md->md_offset == 0);
1532 rlength = hdr->payload_length;
1533 mlength = min_t(uint, rlength, md->md_length);
1535 if (mlength < rlength &&
1536 (md->md_options & LNET_MD_TRUNCATE) == 0) {
1537 CNETERR("%s: Dropping REPLY from %s length %d for MD %#llx would overflow (%d)\n",
1538 libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1539 rlength, hdr->msg.reply.dst_wmd.wh_object_cookie,
1541 lnet_res_unlock(cpt);
1542 return ENOENT; /* +ve: OK but no match */
1545 CDEBUG(D_NET, "%s: Reply from %s of length %d/%d into md %#llx\n",
1546 libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1547 mlength, rlength, hdr->msg.reply.dst_wmd.wh_object_cookie);
1549 lnet_msg_attach_md(msg, md, 0, mlength);
1552 lnet_setpayloadbuffer(msg);
1554 lnet_res_unlock(cpt);
1556 lnet_build_msg_event(msg, LNET_EVENT_REPLY);
1558 lnet_ni_recv(ni, private, msg, 0, 0, mlength, rlength);
1563 lnet_parse_ack(lnet_ni_t *ni, lnet_msg_t *msg)
1565 lnet_hdr_t *hdr = &msg->msg_hdr;
1566 lnet_process_id_t src = {0};
1570 src.nid = hdr->src_nid;
1571 src.pid = hdr->src_pid;
1573 /* Convert ack fields to host byte order */
1574 hdr->msg.ack.match_bits = le64_to_cpu(hdr->msg.ack.match_bits);
1575 hdr->msg.ack.mlength = le32_to_cpu(hdr->msg.ack.mlength);
1577 cpt = lnet_cpt_of_cookie(hdr->msg.ack.dst_wmd.wh_object_cookie);
1580 /* NB handles only looked up by creator (no flips) */
1581 md = lnet_wire_handle2md(&hdr->msg.ack.dst_wmd);
1582 if (md == NULL || md->md_threshold == 0 || md->md_me != NULL) {
1583 /* Don't moan; this is expected */
1585 "%s: Dropping ACK from %s to %s MD %#llx.%#llx\n",
1586 libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1587 (md == NULL) ? "invalid" : "inactive",
1588 hdr->msg.ack.dst_wmd.wh_interface_cookie,
1589 hdr->msg.ack.dst_wmd.wh_object_cookie);
1590 if (md != NULL && md->md_me != NULL)
1591 CERROR("Source MD also attached to portal %d\n",
1592 md->md_me->me_portal);
1594 lnet_res_unlock(cpt);
1595 return ENOENT; /* +ve! */
1598 CDEBUG(D_NET, "%s: ACK from %s into md %#llx\n",
1599 libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1600 hdr->msg.ack.dst_wmd.wh_object_cookie);
1602 lnet_msg_attach_md(msg, md, 0, 0);
1604 lnet_res_unlock(cpt);
1606 lnet_build_msg_event(msg, LNET_EVENT_ACK);
1608 lnet_ni_recv(ni, msg->msg_private, msg, 0, 0, 0, msg->msg_len);
1613 lnet_parse_forward_locked(lnet_ni_t *ni, lnet_msg_t *msg)
1617 if (msg->msg_rxpeer->lp_rtrcredits <= 0 ||
1618 lnet_msg2bufpool(msg)->rbp_credits <= 0) {
1619 if (ni->ni_lnd->lnd_eager_recv == NULL) {
1620 msg->msg_rx_ready_delay = 1;
1622 lnet_net_unlock(msg->msg_rx_cpt);
1623 rc = lnet_ni_eager_recv(ni, msg);
1624 lnet_net_lock(msg->msg_rx_cpt);
1629 rc = lnet_post_routed_recv_locked(msg, 0);
1634 lnet_msgtyp2str(int type)
1643 case LNET_MSG_REPLY:
1645 case LNET_MSG_HELLO:
1651 EXPORT_SYMBOL(lnet_msgtyp2str);
1654 lnet_print_hdr(lnet_hdr_t *hdr)
1656 lnet_process_id_t src = {0};
1657 lnet_process_id_t dst = {0};
1658 char *type_str = lnet_msgtyp2str(hdr->type);
1660 src.nid = hdr->src_nid;
1661 src.pid = hdr->src_pid;
1663 dst.nid = hdr->dest_nid;
1664 dst.pid = hdr->dest_pid;
1666 CWARN("P3 Header at %p of type %s\n", hdr, type_str);
1667 CWARN(" From %s\n", libcfs_id2str(src));
1668 CWARN(" To %s\n", libcfs_id2str(dst));
1670 switch (hdr->type) {
1675 CWARN(" Ptl index %d, ack md %#llx.%#llx, match bits %llu\n",
1676 hdr->msg.put.ptl_index,
1677 hdr->msg.put.ack_wmd.wh_interface_cookie,
1678 hdr->msg.put.ack_wmd.wh_object_cookie,
1679 hdr->msg.put.match_bits);
1680 CWARN(" Length %d, offset %d, hdr data %#llx\n",
1681 hdr->payload_length, hdr->msg.put.offset,
1682 hdr->msg.put.hdr_data);
1686 CWARN(" Ptl index %d, return md %#llx.%#llx, match bits %llu\n",
1687 hdr->msg.get.ptl_index,
1688 hdr->msg.get.return_wmd.wh_interface_cookie,
1689 hdr->msg.get.return_wmd.wh_object_cookie,
1690 hdr->msg.get.match_bits);
1691 CWARN(" Length %d, src offset %d\n",
1692 hdr->msg.get.sink_length,
1693 hdr->msg.get.src_offset);
1697 CWARN(" dst md %#llx.%#llx, manipulated length %d\n",
1698 hdr->msg.ack.dst_wmd.wh_interface_cookie,
1699 hdr->msg.ack.dst_wmd.wh_object_cookie,
1700 hdr->msg.ack.mlength);
1703 case LNET_MSG_REPLY:
1704 CWARN(" dst md %#llx.%#llx, length %d\n",
1705 hdr->msg.reply.dst_wmd.wh_interface_cookie,
1706 hdr->msg.reply.dst_wmd.wh_object_cookie,
1707 hdr->payload_length);
1713 lnet_parse(lnet_ni_t *ni, lnet_hdr_t *hdr, lnet_nid_t from_nid,
1714 void *private, int rdma_req)
1719 struct lnet_msg *msg;
1720 lnet_pid_t dest_pid;
1721 lnet_nid_t dest_nid;
1723 __u32 payload_length;
1726 LASSERT(!in_interrupt());
1728 type = le32_to_cpu(hdr->type);
1729 src_nid = le64_to_cpu(hdr->src_nid);
1730 dest_nid = le64_to_cpu(hdr->dest_nid);
1731 dest_pid = le32_to_cpu(hdr->dest_pid);
1732 payload_length = le32_to_cpu(hdr->payload_length);
1734 for_me = (ni->ni_nid == dest_nid);
1735 cpt = lnet_cpt_of_nid(from_nid);
1740 if (payload_length > 0) {
1741 CERROR("%s, src %s: bad %s payload %d (0 expected)\n",
1742 libcfs_nid2str(from_nid),
1743 libcfs_nid2str(src_nid),
1744 lnet_msgtyp2str(type), payload_length);
1750 case LNET_MSG_REPLY:
1751 if (payload_length >
1752 (__u32)(for_me ? LNET_MAX_PAYLOAD : LNET_MTU)) {
1753 CERROR("%s, src %s: bad %s payload %d (%d max expected)\n",
1754 libcfs_nid2str(from_nid),
1755 libcfs_nid2str(src_nid),
1756 lnet_msgtyp2str(type),
1758 for_me ? LNET_MAX_PAYLOAD : LNET_MTU);
1764 CERROR("%s, src %s: Bad message type 0x%x\n",
1765 libcfs_nid2str(from_nid),
1766 libcfs_nid2str(src_nid), type);
1770 if (the_lnet.ln_routing &&
1771 ni->ni_last_alive != get_seconds()) {
1774 /* NB: so far here is the only place to set NI status to "up */
1775 ni->ni_last_alive = get_seconds();
1776 if (ni->ni_status != NULL &&
1777 ni->ni_status->ns_status == LNET_NI_STATUS_DOWN)
1778 ni->ni_status->ns_status = LNET_NI_STATUS_UP;
1782 /* Regard a bad destination NID as a protocol error. Senders should
1783 * know what they're doing; if they don't they're misconfigured, buggy
1784 * or malicious so we chop them off at the knees :) */
1787 if (LNET_NIDNET(dest_nid) == LNET_NIDNET(ni->ni_nid)) {
1788 /* should have gone direct */
1789 CERROR("%s, src %s: Bad dest nid %s (should have been sent direct)\n",
1790 libcfs_nid2str(from_nid),
1791 libcfs_nid2str(src_nid),
1792 libcfs_nid2str(dest_nid));
1796 if (lnet_islocalnid(dest_nid)) {
1797 /* dest is another local NI; sender should have used
1798 * this node's NID on its own network */
1799 CERROR("%s, src %s: Bad dest nid %s (it's my nid but on a different network)\n",
1800 libcfs_nid2str(from_nid),
1801 libcfs_nid2str(src_nid),
1802 libcfs_nid2str(dest_nid));
1806 if (rdma_req && type == LNET_MSG_GET) {
1807 CERROR("%s, src %s: Bad optimized GET for %s (final destination must be me)\n",
1808 libcfs_nid2str(from_nid),
1809 libcfs_nid2str(src_nid),
1810 libcfs_nid2str(dest_nid));
1814 if (!the_lnet.ln_routing) {
1815 CERROR("%s, src %s: Dropping message for %s (routing not enabled)\n",
1816 libcfs_nid2str(from_nid),
1817 libcfs_nid2str(src_nid),
1818 libcfs_nid2str(dest_nid));
1823 /* Message looks OK; we're not going to return an error, so we MUST
1824 * call back lnd_recv() come what may... */
1826 if (!list_empty(&the_lnet.ln_test_peers) && /* normally we don't */
1827 fail_peer(src_nid, 0)) { /* shall we now? */
1828 CERROR("%s, src %s: Dropping %s to simulate failure\n",
1829 libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1830 lnet_msgtyp2str(type));
1834 msg = lnet_msg_alloc();
1836 CERROR("%s, src %s: Dropping %s (out of memory)\n",
1837 libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1838 lnet_msgtyp2str(type));
1842 /* msg zeroed in lnet_msg_alloc;
1843 * i.e. flags all clear, pointers NULL etc
1846 msg->msg_type = type;
1847 msg->msg_private = private;
1848 msg->msg_receiving = 1;
1849 msg->msg_len = msg->msg_wanted = payload_length;
1850 msg->msg_offset = 0;
1851 msg->msg_hdr = *hdr;
1852 /* for building message event */
1853 msg->msg_from = from_nid;
1855 msg->msg_target.pid = dest_pid;
1856 msg->msg_target.nid = dest_nid;
1857 msg->msg_routing = 1;
1860 /* convert common msg->hdr fields to host byteorder */
1861 msg->msg_hdr.type = type;
1862 msg->msg_hdr.src_nid = src_nid;
1863 msg->msg_hdr.src_pid = le32_to_cpu(msg->msg_hdr.src_pid);
1864 msg->msg_hdr.dest_nid = dest_nid;
1865 msg->msg_hdr.dest_pid = dest_pid;
1866 msg->msg_hdr.payload_length = payload_length;
1870 rc = lnet_nid2peer_locked(&msg->msg_rxpeer, from_nid, cpt);
1872 lnet_net_unlock(cpt);
1873 CERROR("%s, src %s: Dropping %s (error %d looking up sender)\n",
1874 libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1875 lnet_msgtyp2str(type), rc);
1880 if (lnet_isrouter(msg->msg_rxpeer)) {
1881 lnet_peer_set_alive(msg->msg_rxpeer);
1882 if (avoid_asym_router_failure &&
1883 LNET_NIDNET(src_nid) != LNET_NIDNET(from_nid)) {
1884 /* received a remote message from router, update
1885 * remote NI status on this router.
1886 * NB: multi-hop routed message will be ignored.
1888 lnet_router_ni_update_locked(msg->msg_rxpeer,
1889 LNET_NIDNET(src_nid));
1893 lnet_msg_commit(msg, cpt);
1896 rc = lnet_parse_forward_locked(ni, msg);
1897 lnet_net_unlock(cpt);
1902 lnet_ni_recv(ni, msg->msg_private, msg, 0,
1903 0, payload_length, payload_length);
1908 lnet_net_unlock(cpt);
1912 rc = lnet_parse_ack(ni, msg);
1915 rc = lnet_parse_put(ni, msg);
1918 rc = lnet_parse_get(ni, msg, rdma_req);
1920 case LNET_MSG_REPLY:
1921 rc = lnet_parse_reply(ni, msg);
1926 goto free_drop; /* prevent an unused label if !kernel */
1932 LASSERT(rc == ENOENT);
1935 LASSERT(msg->msg_md == NULL);
1936 lnet_finalize(ni, msg, rc);
1939 lnet_drop_message(ni, cpt, private, payload_length);
1942 EXPORT_SYMBOL(lnet_parse);
1945 lnet_drop_delayed_msg_list(struct list_head *head, char *reason)
1947 while (!list_empty(head)) {
1948 lnet_process_id_t id = {0};
1951 msg = list_entry(head->next, lnet_msg_t, msg_list);
1952 list_del(&msg->msg_list);
1954 id.nid = msg->msg_hdr.src_nid;
1955 id.pid = msg->msg_hdr.src_pid;
1957 LASSERT(msg->msg_md == NULL);
1958 LASSERT(msg->msg_rx_delayed);
1959 LASSERT(msg->msg_rxpeer != NULL);
1960 LASSERT(msg->msg_hdr.type == LNET_MSG_PUT);
1962 CWARN("Dropping delayed PUT from %s portal %d match %llu offset %d length %d: %s\n",
1964 msg->msg_hdr.msg.put.ptl_index,
1965 msg->msg_hdr.msg.put.match_bits,
1966 msg->msg_hdr.msg.put.offset,
1967 msg->msg_hdr.payload_length, reason);
1969 /* NB I can't drop msg's ref on msg_rxpeer until after I've
1970 * called lnet_drop_message(), so I just hang onto msg as well
1971 * until that's done */
1973 lnet_drop_message(msg->msg_rxpeer->lp_ni,
1974 msg->msg_rxpeer->lp_cpt,
1975 msg->msg_private, msg->msg_len);
1977 * NB: message will not generate event because w/o attached MD,
1978 * but we still should give error code so lnet_msg_decommit()
1979 * can skip counters operations and other checks.
1981 lnet_finalize(msg->msg_rxpeer->lp_ni, msg, -ENOENT);
1986 lnet_recv_delayed_msg_list(struct list_head *head)
1988 while (!list_empty(head)) {
1990 lnet_process_id_t id;
1992 msg = list_entry(head->next, lnet_msg_t, msg_list);
1993 list_del(&msg->msg_list);
1995 /* md won't disappear under me, since each msg
1996 * holds a ref on it */
1998 id.nid = msg->msg_hdr.src_nid;
1999 id.pid = msg->msg_hdr.src_pid;
2001 LASSERT(msg->msg_rx_delayed);
2002 LASSERT(msg->msg_md != NULL);
2003 LASSERT(msg->msg_rxpeer != NULL);
2004 LASSERT(msg->msg_hdr.type == LNET_MSG_PUT);
2006 CDEBUG(D_NET, "Resuming delayed PUT from %s portal %d match %llu offset %d length %d.\n",
2007 libcfs_id2str(id), msg->msg_hdr.msg.put.ptl_index,
2008 msg->msg_hdr.msg.put.match_bits,
2009 msg->msg_hdr.msg.put.offset,
2010 msg->msg_hdr.payload_length);
2012 lnet_recv_put(msg->msg_rxpeer->lp_ni, msg);
2017 * Initiate an asynchronous PUT operation.
2019 * There are several events associated with a PUT: completion of the send on
2020 * the initiator node (LNET_EVENT_SEND), and when the send completes
2021 * successfully, the receipt of an acknowledgment (LNET_EVENT_ACK) indicating
2022 * that the operation was accepted by the target. The event LNET_EVENT_PUT is
2023 * used at the target node to indicate the completion of incoming data
2026 * The local events will be logged in the EQ associated with the MD pointed to
2027 * by \a mdh handle. Using a MD without an associated EQ results in these
2028 * events being discarded. In this case, the caller must have another
2029 * mechanism (e.g., a higher level protocol) for determining when it is safe
2030 * to modify the memory region associated with the MD.
2032 * Note that LNet does not guarantee the order of LNET_EVENT_SEND and
2033 * LNET_EVENT_ACK, though intuitively ACK should happen after SEND.
2035 * \param self Indicates the NID of a local interface through which to send
2036 * the PUT request. Use LNET_NID_ANY to let LNet choose one by itself.
2037 * \param mdh A handle for the MD that describes the memory to be sent. The MD
2038 * must be "free floating" (See LNetMDBind()).
2039 * \param ack Controls whether an acknowledgment is requested.
2040 * Acknowledgments are only sent when they are requested by the initiating
2041 * process and the target MD enables them.
2042 * \param target A process identifier for the target process.
2043 * \param portal The index in the \a target's portal table.
2044 * \param match_bits The match bits to use for MD selection at the target
2046 * \param offset The offset into the target MD (only used when the target
2047 * MD has the LNET_MD_MANAGE_REMOTE option set).
2048 * \param hdr_data 64 bits of user data that can be included in the message
2049 * header. This data is written to an event queue entry at the target if an
2050 * EQ is present on the matching MD.
2052 * \retval 0 Success, and only in this case events will be generated
2053 * and logged to EQ (if it exists).
2054 * \retval -EIO Simulated failure.
2055 * \retval -ENOMEM Memory allocation failure.
2056 * \retval -ENOENT Invalid MD object.
2058 * \see lnet_event_t::hdr_data and lnet_event_kind_t.
2061 LNetPut(lnet_nid_t self, lnet_handle_md_t mdh, lnet_ack_req_t ack,
2062 lnet_process_id_t target, unsigned int portal,
2063 __u64 match_bits, unsigned int offset,
2066 struct lnet_msg *msg;
2067 struct lnet_libmd *md;
2071 LASSERT(the_lnet.ln_init);
2072 LASSERT(the_lnet.ln_refcount > 0);
2074 if (!list_empty(&the_lnet.ln_test_peers) && /* normally we don't */
2075 fail_peer(target.nid, 1)) { /* shall we now? */
2076 CERROR("Dropping PUT to %s: simulated failure\n",
2077 libcfs_id2str(target));
2081 msg = lnet_msg_alloc();
2083 CERROR("Dropping PUT to %s: ENOMEM on lnet_msg_t\n",
2084 libcfs_id2str(target));
2087 msg->msg_vmflush = !!memory_pressure_get();
2089 cpt = lnet_cpt_of_cookie(mdh.cookie);
2092 md = lnet_handle2md(&mdh);
2093 if (md == NULL || md->md_threshold == 0 || md->md_me != NULL) {
2094 CERROR("Dropping PUT (%llu:%d:%s): MD (%d) invalid\n",
2095 match_bits, portal, libcfs_id2str(target),
2096 md == NULL ? -1 : md->md_threshold);
2097 if (md != NULL && md->md_me != NULL)
2098 CERROR("Source MD also attached to portal %d\n",
2099 md->md_me->me_portal);
2100 lnet_res_unlock(cpt);
2106 CDEBUG(D_NET, "LNetPut -> %s\n", libcfs_id2str(target));
2108 lnet_msg_attach_md(msg, md, 0, 0);
2110 lnet_prep_send(msg, LNET_MSG_PUT, target, 0, md->md_length);
2112 msg->msg_hdr.msg.put.match_bits = cpu_to_le64(match_bits);
2113 msg->msg_hdr.msg.put.ptl_index = cpu_to_le32(portal);
2114 msg->msg_hdr.msg.put.offset = cpu_to_le32(offset);
2115 msg->msg_hdr.msg.put.hdr_data = hdr_data;
2117 /* NB handles only looked up by creator (no flips) */
2118 if (ack == LNET_ACK_REQ) {
2119 msg->msg_hdr.msg.put.ack_wmd.wh_interface_cookie =
2120 the_lnet.ln_interface_cookie;
2121 msg->msg_hdr.msg.put.ack_wmd.wh_object_cookie =
2122 md->md_lh.lh_cookie;
2124 msg->msg_hdr.msg.put.ack_wmd.wh_interface_cookie =
2125 LNET_WIRE_HANDLE_COOKIE_NONE;
2126 msg->msg_hdr.msg.put.ack_wmd.wh_object_cookie =
2127 LNET_WIRE_HANDLE_COOKIE_NONE;
2130 lnet_res_unlock(cpt);
2132 lnet_build_msg_event(msg, LNET_EVENT_SEND);
2134 rc = lnet_send(self, msg, LNET_NID_ANY);
2136 CNETERR("Error sending PUT to %s: %d\n",
2137 libcfs_id2str(target), rc);
2138 lnet_finalize(NULL, msg, rc);
2141 /* completion will be signalled by an event */
2144 EXPORT_SYMBOL(LNetPut);
2147 lnet_create_reply_msg(lnet_ni_t *ni, lnet_msg_t *getmsg)
2149 /* The LND can DMA direct to the GET md (i.e. no REPLY msg). This
2150 * returns a msg for the LND to pass to lnet_finalize() when the sink
2151 * data has been received.
2153 * CAVEAT EMPTOR: 'getmsg' is the original GET, which is freed when
2154 * lnet_finalize() is called on it, so the LND must call this first */
2156 struct lnet_msg *msg = lnet_msg_alloc();
2157 struct lnet_libmd *getmd = getmsg->msg_md;
2158 lnet_process_id_t peer_id = getmsg->msg_target;
2161 LASSERT(!getmsg->msg_target_is_router);
2162 LASSERT(!getmsg->msg_routing);
2164 cpt = lnet_cpt_of_cookie(getmd->md_lh.lh_cookie);
2167 LASSERT(getmd->md_refcount > 0);
2170 CERROR("%s: Dropping REPLY from %s: can't allocate msg\n",
2171 libcfs_nid2str(ni->ni_nid), libcfs_id2str(peer_id));
2175 if (getmd->md_threshold == 0) {
2176 CERROR("%s: Dropping REPLY from %s for inactive MD %p\n",
2177 libcfs_nid2str(ni->ni_nid), libcfs_id2str(peer_id),
2179 lnet_res_unlock(cpt);
2183 LASSERT(getmd->md_offset == 0);
2185 CDEBUG(D_NET, "%s: Reply from %s md %p\n",
2186 libcfs_nid2str(ni->ni_nid), libcfs_id2str(peer_id), getmd);
2188 /* setup information for lnet_build_msg_event */
2189 msg->msg_from = peer_id.nid;
2190 msg->msg_type = LNET_MSG_GET; /* flag this msg as an "optimized" GET */
2191 msg->msg_hdr.src_nid = peer_id.nid;
2192 msg->msg_hdr.payload_length = getmd->md_length;
2193 msg->msg_receiving = 1; /* required by lnet_msg_attach_md */
2195 lnet_msg_attach_md(msg, getmd, getmd->md_offset, getmd->md_length);
2196 lnet_res_unlock(cpt);
2198 cpt = lnet_cpt_of_nid(peer_id.nid);
2201 lnet_msg_commit(msg, cpt);
2202 lnet_net_unlock(cpt);
2204 lnet_build_msg_event(msg, LNET_EVENT_REPLY);
2209 cpt = lnet_cpt_of_nid(peer_id.nid);
2212 the_lnet.ln_counters[cpt]->drop_count++;
2213 the_lnet.ln_counters[cpt]->drop_length += getmd->md_length;
2214 lnet_net_unlock(cpt);
2221 EXPORT_SYMBOL(lnet_create_reply_msg);
2224 lnet_set_reply_msg_len(lnet_ni_t *ni, lnet_msg_t *reply, unsigned int len)
2226 /* Set the REPLY length, now the RDMA that elides the REPLY message has
2227 * completed and I know it. */
2228 LASSERT(reply != NULL);
2229 LASSERT(reply->msg_type == LNET_MSG_GET);
2230 LASSERT(reply->msg_ev.type == LNET_EVENT_REPLY);
2232 /* NB I trusted my peer to RDMA. If she tells me she's written beyond
2233 * the end of my buffer, I might as well be dead. */
2234 LASSERT(len <= reply->msg_ev.mlength);
2236 reply->msg_ev.mlength = len;
2238 EXPORT_SYMBOL(lnet_set_reply_msg_len);
2241 * Initiate an asynchronous GET operation.
2243 * On the initiator node, an LNET_EVENT_SEND is logged when the GET request
2244 * is sent, and an LNET_EVENT_REPLY is logged when the data returned from
2245 * the target node in the REPLY has been written to local MD.
2247 * On the target node, an LNET_EVENT_GET is logged when the GET request
2248 * arrives and is accepted into a MD.
2250 * \param self,target,portal,match_bits,offset See the discussion in LNetPut().
2251 * \param mdh A handle for the MD that describes the memory into which the
2252 * requested data will be received. The MD must be "free floating"
2253 * (See LNetMDBind()).
2255 * \retval 0 Success, and only in this case events will be generated
2256 * and logged to EQ (if it exists) of the MD.
2257 * \retval -EIO Simulated failure.
2258 * \retval -ENOMEM Memory allocation failure.
2259 * \retval -ENOENT Invalid MD object.
2262 LNetGet(lnet_nid_t self, lnet_handle_md_t mdh,
2263 lnet_process_id_t target, unsigned int portal,
2264 __u64 match_bits, unsigned int offset)
2266 struct lnet_msg *msg;
2267 struct lnet_libmd *md;
2271 LASSERT(the_lnet.ln_init);
2272 LASSERT(the_lnet.ln_refcount > 0);
2274 if (!list_empty(&the_lnet.ln_test_peers) && /* normally we don't */
2275 fail_peer(target.nid, 1)) { /* shall we now? */
2276 CERROR("Dropping GET to %s: simulated failure\n",
2277 libcfs_id2str(target));
2281 msg = lnet_msg_alloc();
2283 CERROR("Dropping GET to %s: ENOMEM on lnet_msg_t\n",
2284 libcfs_id2str(target));
2288 cpt = lnet_cpt_of_cookie(mdh.cookie);
2291 md = lnet_handle2md(&mdh);
2292 if (md == NULL || md->md_threshold == 0 || md->md_me != NULL) {
2293 CERROR("Dropping GET (%llu:%d:%s): MD (%d) invalid\n",
2294 match_bits, portal, libcfs_id2str(target),
2295 md == NULL ? -1 : md->md_threshold);
2296 if (md != NULL && md->md_me != NULL)
2297 CERROR("REPLY MD also attached to portal %d\n",
2298 md->md_me->me_portal);
2300 lnet_res_unlock(cpt);
2306 CDEBUG(D_NET, "LNetGet -> %s\n", libcfs_id2str(target));
2308 lnet_msg_attach_md(msg, md, 0, 0);
2310 lnet_prep_send(msg, LNET_MSG_GET, target, 0, 0);
2312 msg->msg_hdr.msg.get.match_bits = cpu_to_le64(match_bits);
2313 msg->msg_hdr.msg.get.ptl_index = cpu_to_le32(portal);
2314 msg->msg_hdr.msg.get.src_offset = cpu_to_le32(offset);
2315 msg->msg_hdr.msg.get.sink_length = cpu_to_le32(md->md_length);
2317 /* NB handles only looked up by creator (no flips) */
2318 msg->msg_hdr.msg.get.return_wmd.wh_interface_cookie =
2319 the_lnet.ln_interface_cookie;
2320 msg->msg_hdr.msg.get.return_wmd.wh_object_cookie =
2321 md->md_lh.lh_cookie;
2323 lnet_res_unlock(cpt);
2325 lnet_build_msg_event(msg, LNET_EVENT_SEND);
2327 rc = lnet_send(self, msg, LNET_NID_ANY);
2329 CNETERR("Error sending GET to %s: %d\n",
2330 libcfs_id2str(target), rc);
2331 lnet_finalize(NULL, msg, rc);
2334 /* completion will be signalled by an event */
2337 EXPORT_SYMBOL(LNetGet);
2340 * Calculate distance to node at \a dstnid.
2342 * \param dstnid Target NID.
2343 * \param srcnidp If not NULL, NID of the local interface to reach \a dstnid
2345 * \param orderp If not NULL, order of the route to reach \a dstnid is saved
2348 * \retval 0 If \a dstnid belongs to a local interface, and reserved option
2349 * local_nid_dist_zero is set, which is the default.
2350 * \retval positives Distance to target NID, i.e. number of hops plus one.
2351 * \retval -EHOSTUNREACH If \a dstnid is not reachable.
2354 LNetDist(lnet_nid_t dstnid, lnet_nid_t *srcnidp, __u32 *orderp)
2356 struct list_head *e;
2358 lnet_remotenet_t *rnet;
2359 __u32 dstnet = LNET_NIDNET(dstnid);
2363 struct list_head *rn_list;
2365 /* if !local_nid_dist_zero, I don't return a distance of 0 ever
2366 * (when lustre sees a distance of 0, it substitutes 0@lo), so I
2367 * keep order 0 free for 0@lo and order 1 free for a local NID
2370 LASSERT(the_lnet.ln_init);
2371 LASSERT(the_lnet.ln_refcount > 0);
2373 cpt = lnet_net_lock_current();
2375 list_for_each(e, &the_lnet.ln_nis) {
2376 ni = list_entry(e, lnet_ni_t, ni_list);
2378 if (ni->ni_nid == dstnid) {
2379 if (srcnidp != NULL)
2381 if (orderp != NULL) {
2382 if (LNET_NETTYP(LNET_NIDNET(dstnid)) == LOLND)
2387 lnet_net_unlock(cpt);
2389 return local_nid_dist_zero ? 0 : 1;
2392 if (LNET_NIDNET(ni->ni_nid) == dstnet) {
2393 if (srcnidp != NULL)
2394 *srcnidp = ni->ni_nid;
2397 lnet_net_unlock(cpt);
2404 rn_list = lnet_net2rnethash(dstnet);
2405 list_for_each(e, rn_list) {
2406 rnet = list_entry(e, lnet_remotenet_t, lrn_list);
2408 if (rnet->lrn_net == dstnet) {
2409 lnet_route_t *route;
2410 lnet_route_t *shortest = NULL;
2412 LASSERT(!list_empty(&rnet->lrn_routes));
2414 list_for_each_entry(route, &rnet->lrn_routes,
2416 if (shortest == NULL ||
2417 route->lr_hops < shortest->lr_hops)
2421 LASSERT(shortest != NULL);
2422 hops = shortest->lr_hops;
2423 if (srcnidp != NULL)
2424 *srcnidp = shortest->lr_gateway->lp_ni->ni_nid;
2427 lnet_net_unlock(cpt);
2433 lnet_net_unlock(cpt);
2434 return -EHOSTUNREACH;
2436 EXPORT_SYMBOL(LNetDist);
2439 * Set the number of asynchronous messages expected from a target process.
2441 * This function is only meaningful for userspace callers. It's a no-op when
2442 * called from kernel.
2444 * Asynchronous messages are those that can come from a target when the
2445 * userspace process is not waiting for IO to complete; e.g., AST callbacks
2446 * from Lustre servers. Specifying the expected number of such messages
2447 * allows them to be eagerly received when user process is not running in
2448 * LNet; otherwise network errors may occur.
2450 * \param id Process ID of the target process.
2451 * \param nasync Number of asynchronous messages expected from the target.
2453 * \return 0 on success, and an error code otherwise.
2456 LNetSetAsync(lnet_process_id_t id, int nasync)
2460 EXPORT_SYMBOL(LNetSetAsync);