/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=8:tabstop=8:
*
- * Copyright (C) 2002 Cluster File Systems, Inc.
+ * GPL HEADER START
*
- * This file is part of Lustre, http://www.lustre.org.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
- * Lustre is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
+ * 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.
*
- * Lustre 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 for more details.
+ * 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
- * along with Lustre; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 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 2008 Sun Microsystems, Inc. All rights reserved
+ * Use is subject to license terms.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
*/
#define DEBUG_SUBSYSTEM S_RPC
#ifdef __KERNEL__
-#include <linux/obd_support.h>
-#include <linux/obd_class.h>
-#include <linux/lustre_net.h>
+#include <obd_support.h>
+#include <obd_class.h>
+#include <lustre_net.h>
#else
#include <liblustre.h>
#endif
#include "ptlrpc_internal.h"
+#include <class_hash.h>
-static spinlock_t conn_lock;
-static struct list_head conn_list;
-static struct list_head conn_unused_list;
+static lustre_hash_t *conn_hash = NULL;
+static lustre_hash_ops_t conn_hash_ops;
-void ptlrpc_dump_connections(void)
+struct ptlrpc_connection *
+ptlrpc_connection_get(lnet_process_id_t peer, lnet_nid_t self,
+ struct obd_uuid *uuid)
{
- struct list_head *tmp;
- struct ptlrpc_connection *c;
+ struct ptlrpc_connection *conn, *conn2;
ENTRY;
- list_for_each(tmp, &conn_list) {
- c = list_entry(tmp, struct ptlrpc_connection, c_link);
- CERROR("Connection %p/%s has refcount %d (nid="LPX64" on %s)\n",
- c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
- c->c_peer.peer_nid, c->c_peer.peer_ni->pni_name);
+ conn = lustre_hash_lookup(conn_hash, &peer);
+ if (conn)
+ GOTO(out, conn);
+
+ OBD_ALLOC_PTR(conn);
+ if (!conn)
+ RETURN(NULL);
+
+ conn->c_peer = peer;
+ conn->c_self = self;
+ INIT_HLIST_NODE(&conn->c_hash);
+ atomic_set(&conn->c_refcount, 1);
+ if (uuid)
+ obd_str2uuid(&conn->c_remote_uuid, uuid->uuid);
+
+ /*
+ * Add the newly created conn to the hash, on key collision we
+ * lost a racing addition and must destroy our newly allocated
+ * connection. The object which exists in the has will be
+ * returned and may be compared against out object.
+ */
+ conn2 = lustre_hash_findadd_unique(conn_hash, &peer, &conn->c_hash);
+ if (conn != conn2) {
+ OBD_FREE_PTR(conn);
+ conn = conn2;
}
EXIT;
+out:
+ CDEBUG(D_INFO, "conn=%p refcount %d to %s\n",
+ conn, atomic_read(&conn->c_refcount),
+ libcfs_nid2str(conn->c_peer.nid));
+ return conn;
}
-
-struct ptlrpc_connection *ptlrpc_get_connection(struct ptlrpc_peer *peer,
- struct obd_uuid *uuid)
+
+int ptlrpc_connection_put(struct ptlrpc_connection *conn)
{
- struct list_head *tmp, *pos;
- struct ptlrpc_connection *c;
+ int rc = 0;
ENTRY;
+
+ if (!conn)
+ RETURN(rc);
+
+ LASSERT(!hlist_unhashed(&conn->c_hash));
+
+ /*
+ * We do not remove connection from hashtable and
+ * do not free it even if last caller released ref,
+ * as we want to have it cached for the case it is
+ * needed again.
+ *
+ * Deallocating it and later creating new connection
+ * again would be wastful. This way we also avoid
+ * expensive locking to protect things from get/put
+ * race when found cached connection is freed by
+ * ptlrpc_connection_put().
+ *
+ * It will be freed later in module unload time,
+ * when ptlrpc_connection_fini()->lh_exit->conn_exit()
+ * path is called.
+ */
+ if (atomic_dec_return(&conn->c_refcount) == 1)
+ rc = 1;
+ CDEBUG(D_INFO, "PUT conn=%p refcount %d to %s\n",
+ conn, atomic_read(&conn->c_refcount),
+ libcfs_nid2str(conn->c_peer.nid));
- CDEBUG(D_INFO, "peer is "LPX64" on %s\n",
- peer->peer_nid, peer->peer_ni->pni_name);
-
- spin_lock(&conn_lock);
- list_for_each(tmp, &conn_list) {
- c = list_entry(tmp, struct ptlrpc_connection, c_link);
- if (peer->peer_nid == c->c_peer.peer_nid &&
- peer->peer_ni == c->c_peer.peer_ni) {
- ptlrpc_connection_addref(c);
- GOTO(out, c);
- }
- }
-
- list_for_each_safe(tmp, pos, &conn_unused_list) {
- c = list_entry(tmp, struct ptlrpc_connection, c_link);
- if (peer->peer_nid == c->c_peer.peer_nid &&
- peer->peer_ni == c->c_peer.peer_ni) {
- ptlrpc_connection_addref(c);
- list_del(&c->c_link);
- list_add(&c->c_link, &conn_list);
- GOTO(out, c);
- }
- }
-
- /* FIXME: this should be a slab once we can validate slab addresses
- * without OOPSing */
- OBD_ALLOC(c, sizeof(*c));
- if (c == NULL)
- GOTO(out, c);
-
- if (uuid && uuid->uuid) /* XXX ???? */
- obd_str2uuid(&c->c_remote_uuid, uuid->uuid);
- atomic_set(&c->c_refcount, 0);
- memcpy(&c->c_peer, peer, sizeof(c->c_peer));
+ RETURN(rc);
+}
+
+struct ptlrpc_connection *
+ptlrpc_connection_addref(struct ptlrpc_connection *conn)
+{
+ ENTRY;
- ptlrpc_connection_addref(c);
+ atomic_inc(&conn->c_refcount);
+ CDEBUG(D_INFO, "conn=%p refcount %d to %s\n",
+ conn, atomic_read(&conn->c_refcount),
+ libcfs_nid2str(conn->c_peer.nid));
- list_add(&c->c_link, &conn_list);
+ RETURN(conn);
+}
+
+int ptlrpc_connection_init(void)
+{
+ ENTRY;
+ conn_hash = lustre_hash_init("CONN_HASH", 32, 32768,
+ &conn_hash_ops, LH_REHASH);
+ if (!conn_hash)
+ RETURN(-ENOMEM);
+
+ RETURN(0);
+}
+
+void ptlrpc_connection_fini(void) {
+ ENTRY;
+ lustre_hash_exit(conn_hash);
EXIT;
- out:
- spin_unlock(&conn_lock);
- return c;
}
-int ptlrpc_put_connection(struct ptlrpc_connection *c)
+/*
+ * Hash operations for net_peer<->connection
+ */
+static unsigned
+conn_hashfn(lustre_hash_t *lh, void *key, unsigned mask)
{
- int rc = 0;
- ENTRY;
+ return lh_djb2_hash(key, sizeof(lnet_process_id_t), mask);
+}
- if (c == NULL) {
- CERROR("NULL connection\n");
- RETURN(0);
- }
+static int
+conn_compare(void *key, struct hlist_node *hnode)
+{
+ struct ptlrpc_connection *conn;
+ lnet_process_id_t *conn_key;
- CDEBUG (D_INFO, "connection=%p refcount %d to "LPX64" on %s\n",
- c, atomic_read(&c->c_refcount) - 1, c->c_peer.peer_nid,
- c->c_peer.peer_ni->pni_name);
+ LASSERT(key != NULL);
+ conn_key = (lnet_process_id_t*)key;
+ conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
- if (atomic_dec_and_test(&c->c_refcount)) {
- spin_lock(&conn_lock);
- list_del(&c->c_link);
- list_add(&c->c_link, &conn_unused_list);
- spin_unlock(&conn_lock);
- rc = 1;
- }
- if (atomic_read(&c->c_refcount) < 0)
- CERROR("connection %p refcount %d!\n",
- c, atomic_read(&c->c_refcount));
+ return conn_key->nid == conn->c_peer.nid &&
+ conn_key->pid == conn->c_peer.pid;
+}
- RETURN(rc);
+static void *
+conn_key(struct hlist_node *hnode)
+{
+ struct ptlrpc_connection *conn;
+ conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
+ return &conn->c_peer;
}
-struct ptlrpc_connection *ptlrpc_connection_addref(struct ptlrpc_connection *c)
+static void *
+conn_get(struct hlist_node *hnode)
{
- ENTRY;
- atomic_inc(&c->c_refcount);
- CDEBUG (D_INFO, "connection=%p refcount %d to "LPX64" on %s\n",
- c, atomic_read(&c->c_refcount), c->c_peer.peer_nid,
- c->c_peer.peer_ni->pni_name);
- RETURN(c);
+ struct ptlrpc_connection *conn;
+
+ conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
+ atomic_inc(&conn->c_refcount);
+
+ return conn;
}
-void ptlrpc_init_connection(void)
+static void *
+conn_put(struct hlist_node *hnode)
{
- INIT_LIST_HEAD(&conn_list);
- INIT_LIST_HEAD(&conn_unused_list);
- conn_lock = SPIN_LOCK_UNLOCKED;
+ struct ptlrpc_connection *conn;
+
+ conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
+ atomic_dec(&conn->c_refcount);
+
+ return conn;
}
-void ptlrpc_cleanup_connection(void)
+static void
+conn_exit(struct hlist_node *hnode)
{
- struct list_head *tmp, *pos;
- struct ptlrpc_connection *c;
-
- spin_lock(&conn_lock);
- list_for_each_safe(tmp, pos, &conn_unused_list) {
- c = list_entry(tmp, struct ptlrpc_connection, c_link);
- list_del(&c->c_link);
- OBD_FREE(c, sizeof(*c));
- }
- list_for_each_safe(tmp, pos, &conn_list) {
- c = list_entry(tmp, struct ptlrpc_connection, c_link);
- CERROR("Connection %p/%s has refcount %d (nid="LPX64" on %s)\n",
- c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
- c->c_peer.peer_nid, c->c_peer.peer_ni->pni_name);
- list_del(&c->c_link);
- OBD_FREE(c, sizeof(*c));
- }
- spin_unlock(&conn_lock);
+ struct ptlrpc_connection *conn;
+
+ conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
+ /*
+ * Nothing should be left. Connection user put it and
+ * connection also was deleted from table by this time
+ * so we should have 0 refs.
+ */
+ LASSERTF(atomic_read(&conn->c_refcount) == 0,
+ "Busy connection with %d refs\n",
+ atomic_read(&conn->c_refcount));
+ OBD_FREE_PTR(conn);
}
+
+static lustre_hash_ops_t conn_hash_ops = {
+ .lh_hash = conn_hashfn,
+ .lh_compare = conn_compare,
+ .lh_key = conn_key,
+ .lh_get = conn_get,
+ .lh_put = conn_put,
+ .lh_exit = conn_exit,
+};