net/smc: Add connection counters for links

Add connection counters to the structure of the link.
Increase/decrease the counters as needed in the corresponding
routines.

Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index af96f813c075281f02784ae04413fa03382aae1b..5bc8ebcd03f3e7eac32f50362652411d2f81f74d 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -139,6 +139,7 @@ static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
        }
        if (!conn->lnk)
                return SMC_CLC_DECL_NOACTLINK;
+       atomic_inc(&conn->lnk->conn_cnt);
        return 0;
 }
 
@@ -180,6 +181,8 @@ static void __smc_lgr_unregister_conn(struct smc_connection *conn)
        struct smc_link_group *lgr = conn->lgr;
 
        rb_erase(&conn->alert_node, &lgr->conns_all);
+       if (conn->lnk)
+               atomic_dec(&conn->lnk->conn_cnt);
        lgr->conns_num--;
        conn->alert_token_local = 0;
        sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
@@ -314,6 +317,7 @@ int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
        lnk->smcibdev = ini->ib_dev;
        lnk->ibport = ini->ib_port;
        lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
+       atomic_set(&lnk->conn_cnt, 0);
        smc_llc_link_set_uid(lnk);
        INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
        if (!ini->ib_dev->initialized) {
@@ -526,6 +530,14 @@ static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
        return rc;
 }
 
+static void smc_switch_link_and_count(struct smc_connection *conn,
+                                     struct smc_link *to_lnk)
+{
+       atomic_dec(&conn->lnk->conn_cnt);
+       conn->lnk = to_lnk;
+       atomic_inc(&conn->lnk->conn_cnt);
+}
+
 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
                                  struct smc_link *from_lnk, bool is_dev_err)
 {
@@ -574,7 +586,7 @@ again:
                    smc->sk.sk_state == SMC_PEERABORTWAIT ||
                    smc->sk.sk_state == SMC_PROCESSABORT) {
                        spin_lock_bh(&conn->send_lock);
-                       conn->lnk = to_lnk;
+                       smc_switch_link_and_count(conn, to_lnk);
                        spin_unlock_bh(&conn->send_lock);
                        continue;
                }
@@ -588,7 +600,7 @@ again:
                }
                /* avoid race with smcr_tx_sndbuf_nonempty() */
                spin_lock_bh(&conn->send_lock);
-               conn->lnk = to_lnk;
+               smc_switch_link_and_count(conn, to_lnk);
                rc = smc_switch_cursor(smc, pend, wr_buf);
                spin_unlock_bh(&conn->send_lock);
                sock_put(&smc->sk);

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 9aee54a6bcba152563bcf5631c396bb7388a2941..eefb6770b26855a0419320fb4cd5caded8a282f4 100644 (file)
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -129,6 +129,7 @@ struct smc_link {
        struct delayed_work     llc_testlink_wrk; /* testlink worker */
        struct completion       llc_testlink_resp; /* wait for rx of testlink */
        int                     llc_testlink_time; /* testlink interval */
+       atomic_t                conn_cnt; /* connections on this link */
 };
 
 /* For now we just allow one parallel link per link group. The SMC protocol