net/smc: eliminate cursor read and write calls

The functions to read and write cursors are exclusively used to copy
cursors. Therefore switch to a respective function instead.

Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 143b222..7fc810e 100644 (file)
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1755,12 +1755,8 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd,
                    smc->sk.sk_state == SMC_CLOSED) {
                        answ = 0;
                } else {
-                       smc_curs_write(&cons,
-                              smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-                                      conn);
-                       smc_curs_write(&urg,
-                                      smc_curs_read(&conn->urg_curs, conn),
-                                      conn);
+                       smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
+                       smc_curs_copy(&urg, &conn->urg_curs, conn);
                        answ = smc_curs_diff(conn->rmb_desc->len,
                                             &cons, &urg) == 1;
                }

diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c
index 621d8cc..f3a1497 100644 (file)
--- a/net/smc/smc_cdc.c
+++ b/net/smc/smc_cdc.c
@@ -34,14 +34,15 @@ static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd,
                               enum ib_wc_status wc_status)
 {
        struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend *)pnd_snd;
+       struct smc_connection *conn = cdcpend->conn;
        struct smc_sock *smc;
        int diff;
 
-       if (!cdcpend->conn)
+       if (!conn)
                /* already dismissed */
                return;
 
-       smc = container_of(cdcpend->conn, struct smc_sock, conn);
+       smc = container_of(conn, struct smc_sock, conn);
        bh_lock_sock(&smc->sk);
        if (!wc_status) {
                diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len,
@@ -52,9 +53,7 @@ static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd,
                atomic_add(diff, &cdcpend->conn->sndbuf_space);
                /* guarantee 0 <= sndbuf_space <= sndbuf_desc->len */
                smp_mb__after_atomic();
-               smc_curs_write(&cdcpend->conn->tx_curs_fin,
-                              smc_curs_read(&cdcpend->cursor, cdcpend->conn),
-                              cdcpend->conn);
+               smc_curs_copy(&conn->tx_curs_fin, &cdcpend->cursor, conn);
        }
        smc_tx_sndbuf_nonfull(smc);
        bh_unlock_sock(&smc->sk);
@@ -110,9 +109,8 @@ int smc_cdc_msg_send(struct smc_connection *conn,
                            &conn->local_tx_ctrl, conn);
        rc = smc_wr_tx_send(link, (struct smc_wr_tx_pend_priv *)pend);
        if (!rc)
-               smc_curs_write(&conn->rx_curs_confirmed,
-                              smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-                              conn);
+               smc_curs_copy(&conn->rx_curs_confirmed,
+                             &conn->local_tx_ctrl.cons, conn);
 
        return rc;
 }
@@ -194,8 +192,8 @@ int smcd_cdc_msg_send(struct smc_connection *conn)
        rc = smcd_tx_ism_write(conn, &cdc, sizeof(cdc), 0, 1);
        if (rc)
                return rc;
-       smc_curs_write(&conn->rx_curs_confirmed,
-                      smc_curs_read(&conn->local_tx_ctrl.cons, conn), conn);
+       smc_curs_copy(&conn->rx_curs_confirmed, &conn->local_tx_ctrl.cons,
+                     conn);
        /* Calculate transmitted data and increment free send buffer space */
        diff = smc_curs_diff(conn->sndbuf_desc->len, &conn->tx_curs_fin,
                             &conn->tx_curs_sent);
@@ -204,8 +202,7 @@ int smcd_cdc_msg_send(struct smc_connection *conn)
        atomic_add(diff, &conn->sndbuf_space);
        /* guarantee 0 <= sndbuf_space <= sndbuf_desc->len */
        smp_mb__after_atomic();
-       smc_curs_write(&conn->tx_curs_fin,
-                      smc_curs_read(&conn->tx_curs_sent, conn), conn);
+       smc_curs_copy(&conn->tx_curs_fin, &conn->tx_curs_sent, conn);
 
        smc_tx_sndbuf_nonfull(smc);
        return rc;
@@ -225,9 +222,7 @@ static void smc_cdc_handle_urg_data_arrival(struct smc_sock *smc,
        char *base;
 
        /* new data included urgent business */
-       smc_curs_write(&conn->urg_curs,
-                      smc_curs_read(&conn->local_rx_ctrl.prod, conn),
-                      conn);
+       smc_curs_copy(&conn->urg_curs, &conn->local_rx_ctrl.prod, conn);
        conn->urg_state = SMC_URG_VALID;
        if (!sock_flag(&smc->sk, SOCK_URGINLINE))
                /* we'll skip the urgent byte, so don't account for it */
@@ -247,12 +242,8 @@ static void smc_cdc_msg_recv_action(struct smc_sock *smc,
        struct smc_connection *conn = &smc->conn;
        int diff_cons, diff_prod;
 
-       smc_curs_write(&prod_old,
-                      smc_curs_read(&conn->local_rx_ctrl.prod, conn),
-                      conn);
-       smc_curs_write(&cons_old,
-                      smc_curs_read(&conn->local_rx_ctrl.cons, conn),
-                      conn);
+       smc_curs_copy(&prod_old, &conn->local_rx_ctrl.prod, conn);
+       smc_curs_copy(&cons_old, &conn->local_rx_ctrl.cons, conn);
        smc_cdc_msg_to_host(&conn->local_rx_ctrl, cdc, conn);
 
        diff_cons = smc_curs_diff(conn->peer_rmbe_size, &cons_old,

diff --git a/net/smc/smc_cdc.h b/net/smc/smc_cdc.h
index 8fbce4f..934df44 100644 (file)
--- a/net/smc/smc_cdc.h
+++ b/net/smc/smc_cdc.h
@@ -104,47 +104,34 @@ static inline u64 smc_curs_read(union smc_host_cursor *curs,
 #endif
 }
 
-static inline u64 smc_curs_read_net(union smc_cdc_cursor *curs,
-                                   struct smc_connection *conn)
-{
-#ifndef KERNEL_HAS_ATOMIC64
-       unsigned long flags;
-       u64 ret;
-
-       spin_lock_irqsave(&conn->acurs_lock, flags);
-       ret = curs->acurs;
-       spin_unlock_irqrestore(&conn->acurs_lock, flags);
-       return ret;
-#else
-       return atomic64_read(&curs->acurs);
-#endif
-}
-
-static inline void smc_curs_write(union smc_host_cursor *curs, u64 val,
-                                 struct smc_connection *conn)
+/* Copy cursor src into tgt */
+static inline void smc_curs_copy(union smc_host_cursor *tgt,
+                                union smc_host_cursor *src,
+                                struct smc_connection *conn)
 {
 #ifndef KERNEL_HAS_ATOMIC64
        unsigned long flags;
 
        spin_lock_irqsave(&conn->acurs_lock, flags);
-       curs->acurs = val;
+       tgt->acurs = src->acurs;
        spin_unlock_irqrestore(&conn->acurs_lock, flags);
 #else
-       atomic64_set(&curs->acurs, val);
+       atomic64_set(&tgt->acurs, atomic64_read(&src->acurs));
 #endif
 }
 
-static inline void smc_curs_write_net(union smc_cdc_cursor *curs, u64 val,
-                                     struct smc_connection *conn)
+static inline void smc_curs_copy_net(union smc_cdc_cursor *tgt,
+                                    union smc_cdc_cursor *src,
+                                    struct smc_connection *conn)
 {
 #ifndef KERNEL_HAS_ATOMIC64
        unsigned long flags;
 
        spin_lock_irqsave(&conn->acurs_lock, flags);
-       curs->acurs = val;
+       tgt->acurs = src->acurs;
        spin_unlock_irqrestore(&conn->acurs_lock, flags);
 #else
-       atomic64_set(&curs->acurs, val);
+       atomic64_set(&tgt->acurs, atomic64_read(&src->acurs));
 #endif
 }
 
@@ -179,7 +166,7 @@ static inline void smc_host_cursor_to_cdc(union smc_cdc_cursor *peer,
 {
        union smc_host_cursor temp;
 
-       smc_curs_write(&temp, smc_curs_read(local, conn), conn);
+       smc_curs_copy(&temp, local, conn);
        peer->count = htonl(temp.count);
        peer->wrap = htons(temp.wrap);
        /* peer->reserved = htons(0); must be ensured by caller */
@@ -206,8 +193,8 @@ static inline void smc_cdc_cursor_to_host(union smc_host_cursor *local,
        union smc_host_cursor temp, old;
        union smc_cdc_cursor net;
 
-       smc_curs_write(&old, smc_curs_read(local, conn), conn);
-       smc_curs_write_net(&net, smc_curs_read_net(peer, conn), conn);
+       smc_curs_copy(&old, local, conn);
+       smc_curs_copy_net(&net, peer, conn);
        temp.count = ntohl(net.count);
        temp.wrap = ntohs(net.wrap);
        if ((old.wrap > temp.wrap) && temp.wrap)
@@ -215,7 +202,7 @@ static inline void smc_cdc_cursor_to_host(union smc_host_cursor *local,
        if ((old.wrap == temp.wrap) &&
            (old.count > temp.count))
                return;
-       smc_curs_write(local, smc_curs_read(&temp, conn), conn);
+       smc_curs_copy(local, &temp, conn);
 }
 
 static inline void smcr_cdc_msg_to_host(struct smc_host_cdc_msg *local,

diff --git a/net/smc/smc_rx.c b/net/smc/smc_rx.c
index b329803..c99c987 100644 (file)
--- a/net/smc/smc_rx.c
+++ b/net/smc/smc_rx.c
@@ -82,8 +82,7 @@ static int smc_rx_update_consumer(struct smc_sock *smc,
                }
        }
 
-       smc_curs_write(&conn->local_tx_ctrl.cons, smc_curs_read(&cons, conn),
-                      conn);
+       smc_curs_copy(&conn->local_tx_ctrl.cons, &cons, conn);
 
        /* send consumer cursor update if required */
        /* similar to advertising new TCP rcv_wnd if required */
@@ -97,8 +96,7 @@ static void smc_rx_update_cons(struct smc_sock *smc, size_t len)
        struct smc_connection *conn = &smc->conn;
        union smc_host_cursor cons;
 
-       smc_curs_write(&cons, smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-                      conn);
+       smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
        smc_rx_update_consumer(smc, cons, len);
 }
 
@@ -245,10 +243,7 @@ static int smc_rx_recv_urg(struct smc_sock *smc, struct msghdr *msg, int len,
                        if (!(flags & MSG_TRUNC))
                                rc = memcpy_to_msg(msg, &conn->urg_rx_byte, 1);
                        len = 1;
-                       smc_curs_write(&cons,
-                                      smc_curs_read(&conn->local_tx_ctrl.cons,
-                                                    conn),
-                                      conn);
+                       smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
                        if (smc_curs_diff(conn->rmb_desc->len, &cons,
                                          &conn->urg_curs) > 1)
                                conn->urg_rx_skip_pend = true;
@@ -370,9 +365,7 @@ copy:
                        continue;
                }
 
-               smc_curs_write(&cons,
-                              smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-                              conn);
+               smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
                /* subsequent splice() calls pick up where previous left */
                if (splbytes)
                        smc_curs_add(conn->rmb_desc->len, &cons, splbytes);

diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c
index 142bcb1..2f5e324 100644 (file)
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -181,9 +181,7 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len)
                copylen = min_t(size_t, send_remaining, writespace);
                /* determine start of sndbuf */
                sndbuf_base = conn->sndbuf_desc->cpu_addr;
-               smc_curs_write(&prep,
-                              smc_curs_read(&conn->tx_curs_prep, conn),
-                              conn);
+               smc_curs_copy(&prep, &conn->tx_curs_prep, conn);
                tx_cnt_prep = prep.count;
                /* determine chunks where to write into sndbuf */
                /* either unwrapped case, or 1st chunk of wrapped case */
@@ -214,9 +212,7 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len)
                smc_sndbuf_sync_sg_for_device(conn);
                /* update cursors */
                smc_curs_add(conn->sndbuf_desc->len, &prep, copylen);
-               smc_curs_write(&conn->tx_curs_prep,
-                              smc_curs_read(&prep, conn),
-                              conn);
+               smc_curs_copy(&conn->tx_curs_prep, &prep, conn);
                /* increased in send tasklet smc_cdc_tx_handler() */
                smp_mb__before_atomic();
                atomic_sub(copylen, &conn->sndbuf_space);
@@ -417,8 +413,8 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
        int rc;
 
        /* source: sndbuf */
-       smc_curs_write(&sent, smc_curs_read(&conn->tx_curs_sent, conn), conn);
-       smc_curs_write(&prep, smc_curs_read(&conn->tx_curs_prep, conn), conn);
+       smc_curs_copy(&sent, &conn->tx_curs_sent, conn);
+       smc_curs_copy(&prep, &conn->tx_curs_prep, conn);
        /* cf. wmem_alloc - (snd_max - snd_una) */
        to_send = smc_curs_diff(conn->sndbuf_desc->len, &sent, &prep);
        if (to_send <= 0)
@@ -429,12 +425,8 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
        rmbespace = atomic_read(&conn->peer_rmbe_space);
        if (rmbespace <= 0)
                return 0;
-       smc_curs_write(&prod,
-                      smc_curs_read(&conn->local_tx_ctrl.prod, conn),
-                      conn);
-       smc_curs_write(&cons,
-                      smc_curs_read(&conn->local_rx_ctrl.cons, conn),
-                      conn);
+       smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
+       smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 
        /* if usable snd_wnd closes ask peer to advertise once it opens again */
        pflags = &conn->local_tx_ctrl.prod_flags;
@@ -481,14 +473,9 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
                pflags->urg_data_present = 1;
        smc_tx_advance_cursors(conn, &prod, &sent, len);
        /* update connection's cursors with advanced local cursors */
-       smc_curs_write(&conn->local_tx_ctrl.prod,
-                      smc_curs_read(&prod, conn),
-                      conn);
+       smc_curs_copy(&conn->local_tx_ctrl.prod, &prod, conn);
                                                        /* dst: peer RMBE */
-       smc_curs_write(&conn->tx_curs_sent,
-                      smc_curs_read(&sent, conn),
-                      conn);
-                                                       /* src: local sndbuf */
+       smc_curs_copy(&conn->tx_curs_sent, &sent, conn);/* src: local sndbuf */
 
        return 0;
 }
@@ -606,17 +593,11 @@ void smc_tx_consumer_update(struct smc_connection *conn, bool force)
        int sender_free = conn->rmb_desc->len;
        int to_confirm;
 
-       smc_curs_write(&cons,
-                      smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-                      conn);
-       smc_curs_write(&cfed,
-                      smc_curs_read(&conn->rx_curs_confirmed, conn),
-                      conn);
+       smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
+       smc_curs_copy(&cfed, &conn->rx_curs_confirmed, conn);
        to_confirm = smc_curs_diff(conn->rmb_desc->len, &cfed, &cons);
        if (to_confirm > conn->rmbe_update_limit) {
-               smc_curs_write(&prod,
-                              smc_curs_read(&conn->local_rx_ctrl.prod, conn),
-                              conn);
+               smc_curs_copy(&prod, &conn->local_rx_ctrl.prod, conn);
                sender_free = conn->rmb_desc->len -
                              smc_curs_diff(conn->rmb_desc->len, &prod, &cfed);
        }
@@ -632,9 +613,8 @@ void smc_tx_consumer_update(struct smc_connection *conn, bool force)
                                              SMC_TX_WORK_DELAY);
                        return;
                }
-               smc_curs_write(&conn->rx_curs_confirmed,
-                              smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-                              conn);
+               smc_curs_copy(&conn->rx_curs_confirmed,
+                             &conn->local_tx_ctrl.cons, conn);
                conn->local_rx_ctrl.prod_flags.cons_curs_upd_req = 0;
        }
        if (conn->local_rx_ctrl.prod_flags.write_blocked &&

diff --git a/net/smc/smc_tx.h b/net/smc/smc_tx.h
index b22bdc5..07e6ad7 100644 (file)
--- a/net/smc/smc_tx.h
+++ b/net/smc/smc_tx.h
@@ -22,8 +22,8 @@ static inline int smc_tx_prepared_sends(struct smc_connection *conn)
 {
        union smc_host_cursor sent, prep;
 
-       smc_curs_write(&sent, smc_curs_read(&conn->tx_curs_sent, conn), conn);
-       smc_curs_write(&prep, smc_curs_read(&conn->tx_curs_prep, conn), conn);
+       smc_curs_copy(&sent, &conn->tx_curs_sent, conn);
+       smc_curs_copy(&prep, &conn->tx_curs_prep, conn);
        return smc_curs_diff(conn->sndbuf_desc->len, &sent, &prep);
 }