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37 #define DEBUG_SUBSYSTEM S_RPC
39 #include <obd_support.h>
40 #include <obd_class.h>
41 #include <lustre_net.h>
43 #include <liblustre.h>
46 #include "ptlrpc_internal.h"
48 static cfs_hash_t *conn_hash = NULL;
49 static cfs_hash_ops_t conn_hash_ops;
51 struct ptlrpc_connection *
52 ptlrpc_connection_get(lnet_process_id_t peer, lnet_nid_t self,
53 struct obd_uuid *uuid)
55 struct ptlrpc_connection *conn, *conn2;
58 conn = cfs_hash_lookup(conn_hash, &peer);
68 CFS_INIT_HLIST_NODE(&conn->c_hash);
69 cfs_atomic_set(&conn->c_refcount, 1);
71 obd_str2uuid(&conn->c_remote_uuid, uuid->uuid);
74 * Add the newly created conn to the hash, on key collision we
75 * lost a racing addition and must destroy our newly allocated
76 * connection. The object which exists in the has will be
77 * returned and may be compared against out object.
79 /* In the function below, .hs_keycmp resolves to
81 /* coverity[overrun-buffer-val] */
82 conn2 = cfs_hash_findadd_unique(conn_hash, &peer, &conn->c_hash);
89 CDEBUG(D_INFO, "conn=%p refcount %d to %s\n",
90 conn, cfs_atomic_read(&conn->c_refcount),
91 libcfs_nid2str(conn->c_peer.nid));
94 EXPORT_SYMBOL(ptlrpc_connection_get);
96 int ptlrpc_connection_put(struct ptlrpc_connection *conn)
104 LASSERT(cfs_atomic_read(&conn->c_refcount) > 1);
107 * We do not remove connection from hashtable and
108 * do not free it even if last caller released ref,
109 * as we want to have it cached for the case it is
112 * Deallocating it and later creating new connection
113 * again would be wastful. This way we also avoid
114 * expensive locking to protect things from get/put
115 * race when found cached connection is freed by
116 * ptlrpc_connection_put().
118 * It will be freed later in module unload time,
119 * when ptlrpc_connection_fini()->lh_exit->conn_exit()
122 if (cfs_atomic_dec_return(&conn->c_refcount) == 1)
125 CDEBUG(D_INFO, "PUT conn=%p refcount %d to %s\n",
126 conn, cfs_atomic_read(&conn->c_refcount),
127 libcfs_nid2str(conn->c_peer.nid));
131 EXPORT_SYMBOL(ptlrpc_connection_put);
133 struct ptlrpc_connection *
134 ptlrpc_connection_addref(struct ptlrpc_connection *conn)
138 cfs_atomic_inc(&conn->c_refcount);
139 CDEBUG(D_INFO, "conn=%p refcount %d to %s\n",
140 conn, cfs_atomic_read(&conn->c_refcount),
141 libcfs_nid2str(conn->c_peer.nid));
145 EXPORT_SYMBOL(ptlrpc_connection_addref);
147 int ptlrpc_connection_init(void)
151 conn_hash = cfs_hash_create("CONN_HASH",
154 HASH_CONN_BKT_BITS, 0,
157 &conn_hash_ops, CFS_HASH_DEFAULT);
163 EXPORT_SYMBOL(ptlrpc_connection_init);
165 void ptlrpc_connection_fini(void) {
167 cfs_hash_putref(conn_hash);
170 EXPORT_SYMBOL(ptlrpc_connection_fini);
173 * Hash operations for net_peer<->connection
176 conn_hashfn(cfs_hash_t *hs, const void *key, unsigned mask)
178 return cfs_hash_djb2_hash(key, sizeof(lnet_process_id_t), mask);
182 conn_keycmp(const void *key, cfs_hlist_node_t *hnode)
184 struct ptlrpc_connection *conn;
185 const lnet_process_id_t *conn_key;
187 LASSERT(key != NULL);
188 conn_key = (lnet_process_id_t*)key;
189 conn = cfs_hlist_entry(hnode, struct ptlrpc_connection, c_hash);
191 return conn_key->nid == conn->c_peer.nid &&
192 conn_key->pid == conn->c_peer.pid;
196 conn_key(cfs_hlist_node_t *hnode)
198 struct ptlrpc_connection *conn;
199 conn = cfs_hlist_entry(hnode, struct ptlrpc_connection, c_hash);
200 return &conn->c_peer;
204 conn_object(cfs_hlist_node_t *hnode)
206 return cfs_hlist_entry(hnode, struct ptlrpc_connection, c_hash);
210 conn_get(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
212 struct ptlrpc_connection *conn;
214 conn = cfs_hlist_entry(hnode, struct ptlrpc_connection, c_hash);
215 cfs_atomic_inc(&conn->c_refcount);
219 conn_put_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
221 struct ptlrpc_connection *conn;
223 conn = cfs_hlist_entry(hnode, struct ptlrpc_connection, c_hash);
224 cfs_atomic_dec(&conn->c_refcount);
228 conn_exit(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
230 struct ptlrpc_connection *conn;
232 conn = cfs_hlist_entry(hnode, struct ptlrpc_connection, c_hash);
234 * Nothing should be left. Connection user put it and
235 * connection also was deleted from table by this time
236 * so we should have 0 refs.
238 LASSERTF(cfs_atomic_read(&conn->c_refcount) == 0,
239 "Busy connection with %d refs\n",
240 cfs_atomic_read(&conn->c_refcount));
244 static cfs_hash_ops_t conn_hash_ops = {
245 .hs_hash = conn_hashfn,
246 .hs_keycmp = conn_keycmp,
248 .hs_object = conn_object,
250 .hs_put_locked = conn_put_locked,
251 .hs_exit = conn_exit,