1 files changed, 337 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lnet/lnet/peer.c b/drivers/staging/lustre/lnet/lnet/peer.c
new file mode 100644
index 000000000000..286977691393
--- /dev/null
+++ b/drivers/staging/lustre/lnet/lnet/peer.c
@@ -0,0 +1,337 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ *
+ * lnet/lnet/peer.c
+ */
+
+#define DEBUG_SUBSYSTEM S_LNET
+
+#include <linux/lnet/lib-lnet.h>
+
+int
+lnet_peer_tables_create(void)
+{
+	struct lnet_peer_table	*ptable;
+	struct list_head		*hash;
+	int			i;
+	int			j;
+
+	the_lnet.ln_peer_tables = cfs_percpt_alloc(lnet_cpt_table(),
+						   sizeof(*ptable));
+	if (the_lnet.ln_peer_tables == NULL) {
+		CERROR("Failed to allocate cpu-partition peer tables\n");
+		return -ENOMEM;
+	}
+
+	cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
+		INIT_LIST_HEAD(&ptable->pt_deathrow);
+
+		LIBCFS_CPT_ALLOC(hash, lnet_cpt_table(), i,
+				 LNET_PEER_HASH_SIZE * sizeof(*hash));
+		if (hash == NULL) {
+			CERROR("Failed to create peer hash table\n");
+			lnet_peer_tables_destroy();
+			return -ENOMEM;
+		}
+
+		for (j = 0; j < LNET_PEER_HASH_SIZE; j++)
+			INIT_LIST_HEAD(&hash[j]);
+		ptable->pt_hash = hash; /* sign of initialization */
+	}
+
+	return 0;
+}
+
+void
+lnet_peer_tables_destroy(void)
+{
+	struct lnet_peer_table	*ptable;
+	struct list_head		*hash;
+	int			i;
+	int			j;
+
+	if (the_lnet.ln_peer_tables == NULL)
+		return;
+
+	cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
+		hash = ptable->pt_hash;
+		if (hash == NULL) /* not intialized */
+			break;
+
+		LASSERT(list_empty(&ptable->pt_deathrow));
+
+		ptable->pt_hash = NULL;
+		for (j = 0; j < LNET_PEER_HASH_SIZE; j++)
+			LASSERT(list_empty(&hash[j]));
+
+		LIBCFS_FREE(hash, LNET_PEER_HASH_SIZE * sizeof(*hash));
+	}
+
+	cfs_percpt_free(the_lnet.ln_peer_tables);
+	the_lnet.ln_peer_tables = NULL;
+}
+
+void
+lnet_peer_tables_cleanup(void)
+{
+	struct lnet_peer_table	*ptable;
+	int			i;
+	int			j;
+
+	LASSERT(the_lnet.ln_shutdown);	/* i.e. no new peers */
+
+	cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
+		lnet_net_lock(i);
+
+		for (j = 0; j < LNET_PEER_HASH_SIZE; j++) {
+			struct list_head *peers = &ptable->pt_hash[j];
+
+			while (!list_empty(peers)) {
+				lnet_peer_t *lp = list_entry(peers->next,
+								 lnet_peer_t,
+								 lp_hashlist);
+				list_del_init(&lp->lp_hashlist);
+				/* lose hash table's ref */
+				lnet_peer_decref_locked(lp);
+			}
+		}
+
+		lnet_net_unlock(i);
+	}
+
+	cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
+		LIST_HEAD	(deathrow);
+		lnet_peer_t	*lp;
+
+		lnet_net_lock(i);
+
+		for (j = 3; ptable->pt_number != 0; j++) {
+			lnet_net_unlock(i);
+
+			if ((j & (j - 1)) == 0) {
+				CDEBUG(D_WARNING,
+				       "Waiting for %d peers on peer table\n",
+				       ptable->pt_number);
+			}
+			cfs_pause(cfs_time_seconds(1) / 2);
+			lnet_net_lock(i);
+		}
+		list_splice_init(&ptable->pt_deathrow, &deathrow);
+
+		lnet_net_unlock(i);
+
+		while (!list_empty(&deathrow)) {
+			lp = list_entry(deathrow.next,
+					    lnet_peer_t, lp_hashlist);
+			list_del(&lp->lp_hashlist);
+			LIBCFS_FREE(lp, sizeof(*lp));
+		}
+	}
+}
+
+void
+lnet_destroy_peer_locked(lnet_peer_t *lp)
+{
+	struct lnet_peer_table *ptable;
+
+	LASSERT(lp->lp_refcount == 0);
+	LASSERT(lp->lp_rtr_refcount == 0);
+	LASSERT(list_empty(&lp->lp_txq));
+	LASSERT(list_empty(&lp->lp_hashlist));
+	LASSERT(lp->lp_txqnob == 0);
+
+	ptable = the_lnet.ln_peer_tables[lp->lp_cpt];
+	LASSERT(ptable->pt_number > 0);
+	ptable->pt_number--;
+
+	lnet_ni_decref_locked(lp->lp_ni, lp->lp_cpt);
+	lp->lp_ni = NULL;
+
+	list_add(&lp->lp_hashlist, &ptable->pt_deathrow);
+}
+
+lnet_peer_t *
+lnet_find_peer_locked(struct lnet_peer_table *ptable, lnet_nid_t nid)
+{
+	struct list_head	*peers;
+	lnet_peer_t	*lp;
+
+	LASSERT(!the_lnet.ln_shutdown);
+
+	peers = &ptable->pt_hash[lnet_nid2peerhash(nid)];
+	list_for_each_entry(lp, peers, lp_hashlist) {
+		if (lp->lp_nid == nid) {
+			lnet_peer_addref_locked(lp);
+			return lp;
+		}
+	}
+
+	return NULL;
+}
+
+int
+lnet_nid2peer_locked(lnet_peer_t **lpp, lnet_nid_t nid, int cpt)
+{
+	struct lnet_peer_table	*ptable;
+	lnet_peer_t		*lp = NULL;
+	lnet_peer_t		*lp2;
+	int			cpt2;
+	int			rc = 0;
+
+	*lpp = NULL;
+	if (the_lnet.ln_shutdown) /* it's shutting down */
+		return -ESHUTDOWN;
+
+	/* cpt can be LNET_LOCK_EX if it's called from router functions */
+	cpt2 = cpt != LNET_LOCK_EX ? cpt : lnet_cpt_of_nid_locked(nid);
+
+	ptable = the_lnet.ln_peer_tables[cpt2];
+	lp = lnet_find_peer_locked(ptable, nid);
+	if (lp != NULL) {
+		*lpp = lp;
+		return 0;
+	}
+
+	if (!list_empty(&ptable->pt_deathrow)) {
+		lp = list_entry(ptable->pt_deathrow.next,
+				    lnet_peer_t, lp_hashlist);
+		list_del(&lp->lp_hashlist);
+	}
+
+	/*
+	 * take extra refcount in case another thread has shutdown LNet
+	 * and destroyed locks and peer-table before I finish the allocation
+	 */
+	ptable->pt_number++;
+	lnet_net_unlock(cpt);
+
+	if (lp != NULL)
+		memset(lp, 0, sizeof(*lp));
+	else
+		LIBCFS_CPT_ALLOC(lp, lnet_cpt_table(), cpt2, sizeof(*lp));
+
+	if (lp == NULL) {
+		rc = -ENOMEM;
+		lnet_net_lock(cpt);
+		goto out;
+	}
+
+	INIT_LIST_HEAD(&lp->lp_txq);
+	INIT_LIST_HEAD(&lp->lp_rtrq);
+	INIT_LIST_HEAD(&lp->lp_routes);
+
+	lp->lp_notify = 0;
+	lp->lp_notifylnd = 0;
+	lp->lp_notifying = 0;
+	lp->lp_alive_count = 0;
+	lp->lp_timestamp = 0;
+	lp->lp_alive = !lnet_peers_start_down(); /* 1 bit!! */
+	lp->lp_last_alive = cfs_time_current(); /* assumes alive */
+	lp->lp_last_query = 0; /* haven't asked NI yet */
+	lp->lp_ping_timestamp = 0;
+	lp->lp_ping_feats = LNET_PING_FEAT_INVAL;
+	lp->lp_nid = nid;
+	lp->lp_cpt = cpt2;
+	lp->lp_refcount = 2;	/* 1 for caller; 1 for hash */
+	lp->lp_rtr_refcount = 0;
+
+	lnet_net_lock(cpt);
+
+	if (the_lnet.ln_shutdown) {
+		rc = -ESHUTDOWN;
+		goto out;
+	}
+
+	lp2 = lnet_find_peer_locked(ptable, nid);
+	if (lp2 != NULL) {
+		*lpp = lp2;
+		goto out;
+	}
+
+	lp->lp_ni = lnet_net2ni_locked(LNET_NIDNET(nid), cpt2);
+	if (lp->lp_ni == NULL) {
+		rc = -EHOSTUNREACH;
+		goto out;
+	}
+
+	lp->lp_txcredits    =
+	lp->lp_mintxcredits = lp->lp_ni->ni_peertxcredits;
+	lp->lp_rtrcredits    =
+	lp->lp_minrtrcredits = lnet_peer_buffer_credits(lp->lp_ni);
+
+	list_add_tail(&lp->lp_hashlist,
+			  &ptable->pt_hash[lnet_nid2peerhash(nid)]);
+	ptable->pt_version++;
+	*lpp = lp;
+
+	return 0;
+out:
+	if (lp != NULL)
+		list_add(&lp->lp_hashlist, &ptable->pt_deathrow);
+	ptable->pt_number--;
+	return rc;
+}
+
+void
+lnet_debug_peer(lnet_nid_t nid)
+{
+	char		*aliveness = "NA";
+	lnet_peer_t	*lp;
+	int		rc;
+	int		cpt;
+
+	cpt = lnet_cpt_of_nid(nid);
+	lnet_net_lock(cpt);
+
+	rc = lnet_nid2peer_locked(&lp, nid, cpt);
+	if (rc != 0) {
+		lnet_net_unlock(cpt);
+		CDEBUG(D_WARNING, "No peer %s\n", libcfs_nid2str(nid));
+		return;
+	}
+
+	if (lnet_isrouter(lp) || lnet_peer_aliveness_enabled(lp))
+		aliveness = lp->lp_alive ? "up" : "down";
+
+	CDEBUG(D_WARNING, "%-24s %4d %5s %5d %5d %5d %5d %5d %ld\n",
+	       libcfs_nid2str(lp->lp_nid), lp->lp_refcount,
+	       aliveness, lp->lp_ni->ni_peertxcredits,
+	       lp->lp_rtrcredits, lp->lp_minrtrcredits,
+	       lp->lp_txcredits, lp->lp_mintxcredits, lp->lp_txqnob);
+
+	lnet_peer_decref_locked(lp);
+
+	lnet_net_unlock(cpt);
+}