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37 #define DEBUG_SUBSYSTEM S_RPC
38 #include <obd_support.h>
39 #include <obd_class.h>
40 #include <lustre_net.h>
42 #include "ptlrpc_internal.h"
44 static cfs_hash_t *conn_hash = NULL;
45 static cfs_hash_ops_t conn_hash_ops;
47 struct ptlrpc_connection *
48 ptlrpc_connection_get(lnet_process_id_t peer, lnet_nid_t self,
49 struct obd_uuid *uuid)
51 struct ptlrpc_connection *conn, *conn2;
54 conn = cfs_hash_lookup(conn_hash, &peer);
64 INIT_HLIST_NODE(&conn->c_hash);
65 atomic_set(&conn->c_refcount, 1);
67 obd_str2uuid(&conn->c_remote_uuid, uuid->uuid);
70 * Add the newly created conn to the hash, on key collision we
71 * lost a racing addition and must destroy our newly allocated
72 * connection. The object which exists in the has will be
73 * returned and may be compared against out object.
75 /* In the function below, .hs_keycmp resolves to
77 /* coverity[overrun-buffer-val] */
78 conn2 = cfs_hash_findadd_unique(conn_hash, &peer, &conn->c_hash);
85 CDEBUG(D_INFO, "conn=%p refcount %d to %s\n",
86 conn, atomic_read(&conn->c_refcount),
87 libcfs_nid2str(conn->c_peer.nid));
90 EXPORT_SYMBOL(ptlrpc_connection_get);
92 int ptlrpc_connection_put(struct ptlrpc_connection *conn)
100 LASSERT(atomic_read(&conn->c_refcount) > 1);
103 * We do not remove connection from hashtable and
104 * do not free it even if last caller released ref,
105 * as we want to have it cached for the case it is
108 * Deallocating it and later creating new connection
109 * again would be wastful. This way we also avoid
110 * expensive locking to protect things from get/put
111 * race when found cached connection is freed by
112 * ptlrpc_connection_put().
114 * It will be freed later in module unload time,
115 * when ptlrpc_connection_fini()->lh_exit->conn_exit()
118 if (atomic_dec_return(&conn->c_refcount) == 1)
121 CDEBUG(D_INFO, "PUT conn=%p refcount %d to %s\n",
122 conn, atomic_read(&conn->c_refcount),
123 libcfs_nid2str(conn->c_peer.nid));
127 EXPORT_SYMBOL(ptlrpc_connection_put);
129 struct ptlrpc_connection *
130 ptlrpc_connection_addref(struct ptlrpc_connection *conn)
134 atomic_inc(&conn->c_refcount);
135 CDEBUG(D_INFO, "conn=%p refcount %d to %s\n",
136 conn, atomic_read(&conn->c_refcount),
137 libcfs_nid2str(conn->c_peer.nid));
141 EXPORT_SYMBOL(ptlrpc_connection_addref);
143 int ptlrpc_connection_init(void)
147 conn_hash = cfs_hash_create("CONN_HASH",
150 HASH_CONN_BKT_BITS, 0,
153 &conn_hash_ops, CFS_HASH_DEFAULT);
159 EXPORT_SYMBOL(ptlrpc_connection_init);
161 void ptlrpc_connection_fini(void) {
163 cfs_hash_putref(conn_hash);
166 EXPORT_SYMBOL(ptlrpc_connection_fini);
169 * Hash operations for net_peer<->connection
172 conn_hashfn(cfs_hash_t *hs, const void *key, unsigned mask)
174 return cfs_hash_djb2_hash(key, sizeof(lnet_process_id_t), mask);
178 conn_keycmp(const void *key, struct hlist_node *hnode)
180 struct ptlrpc_connection *conn;
181 const lnet_process_id_t *conn_key;
183 LASSERT(key != NULL);
184 conn_key = (lnet_process_id_t *)key;
185 conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
187 return conn_key->nid == conn->c_peer.nid &&
188 conn_key->pid == conn->c_peer.pid;
192 conn_key(struct hlist_node *hnode)
194 struct ptlrpc_connection *conn;
195 conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
196 return &conn->c_peer;
200 conn_object(struct hlist_node *hnode)
202 return hlist_entry(hnode, struct ptlrpc_connection, c_hash);
206 conn_get(cfs_hash_t *hs, struct hlist_node *hnode)
208 struct ptlrpc_connection *conn;
210 conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
211 atomic_inc(&conn->c_refcount);
215 conn_put_locked(cfs_hash_t *hs, struct hlist_node *hnode)
217 struct ptlrpc_connection *conn;
219 conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
220 atomic_dec(&conn->c_refcount);
224 conn_exit(cfs_hash_t *hs, struct hlist_node *hnode)
226 struct ptlrpc_connection *conn;
228 conn = hlist_entry(hnode, struct ptlrpc_connection, c_hash);
230 * Nothing should be left. Connection user put it and
231 * connection also was deleted from table by this time
232 * so we should have 0 refs.
234 LASSERTF(atomic_read(&conn->c_refcount) == 0,
235 "Busy connection with %d refs\n",
236 atomic_read(&conn->c_refcount));
240 static cfs_hash_ops_t conn_hash_ops = {
241 .hs_hash = conn_hashfn,
242 .hs_keycmp = conn_keycmp,
244 .hs_object = conn_object,
246 .hs_put_locked = conn_put_locked,
247 .hs_exit = conn_exit,