RDS: Add support for SO_TIMESTAMP for incoming messages

The SO_TIMESTAMP generates time stamp for each incoming RDS messages
User app can enable it by using SO_TIMESTAMP setsocketopt() at
SOL_SOCKET level. CMSG data of cmsg type SO_TIMESTAMP contains the
time stamp in struct timeval format.

Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/rds/af_rds.c b/net/rds/af_rds.c
index b5476ae..6beaeb1 100644 (file)
--- a/net/rds/af_rds.c
+++ b/net/rds/af_rds.c
@@ -277,6 +277,27 @@ static int rds_set_transport(struct rds_sock *rs, char __user *optval,
        return rs->rs_transport ? 0 : -ENOPROTOOPT;
 }
 
+static int rds_enable_recvtstamp(struct sock *sk, char __user *optval,
+                                int optlen)
+{
+       int val, valbool;
+
+       if (optlen != sizeof(int))
+               return -EFAULT;
+
+       if (get_user(val, (int __user *)optval))
+               return -EFAULT;
+
+       valbool = val ? 1 : 0;
+
+       if (valbool)
+               sock_set_flag(sk, SOCK_RCVTSTAMP);
+       else
+               sock_reset_flag(sk, SOCK_RCVTSTAMP);
+
+       return 0;
+}
+
 static int rds_setsockopt(struct socket *sock, int level, int optname,
                          char __user *optval, unsigned int optlen)
 {
@@ -312,6 +333,11 @@ static int rds_setsockopt(struct socket *sock, int level, int optname,
                ret = rds_set_transport(rs, optval, optlen);
                release_sock(sock->sk);
                break;
+       case SO_TIMESTAMP:
+               lock_sock(sock->sk);
+               ret = rds_enable_recvtstamp(sock->sk, optval, optlen);
+               release_sock(sock->sk);
+               break;
        default:
                ret = -ENOPROTOOPT;
        }

diff --git a/net/rds/rds.h b/net/rds/rds.h
index 0e2797b..80256b0 100644 (file)
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -222,6 +222,7 @@ struct rds_incoming {
        __be32                  i_saddr;
 
        rds_rdma_cookie_t       i_rdma_cookie;
+       struct timeval          i_rx_tstamp;
 };
 
 struct rds_mr {

diff --git a/net/rds/recv.c b/net/rds/recv.c
index a00462b..c0be1ec 100644 (file)
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -35,6 +35,8 @@
 #include <net/sock.h>
 #include <linux/in.h>
 #include <linux/export.h>
+#include <linux/time.h>
+#include <linux/rds.h>
 
 #include "rds.h"
 
@@ -46,6 +48,8 @@ void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
        inc->i_conn = conn;
        inc->i_saddr = saddr;
        inc->i_rdma_cookie = 0;
+       inc->i_rx_tstamp.tv_sec = 0;
+       inc->i_rx_tstamp.tv_usec = 0;
 }
 EXPORT_SYMBOL_GPL(rds_inc_init);
 
@@ -228,6 +232,8 @@ void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr,
                rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
                                      be32_to_cpu(inc->i_hdr.h_len),
                                      inc->i_hdr.h_dport);
+               if (sock_flag(sk, SOCK_RCVTSTAMP))
+                       do_gettimeofday(&inc->i_rx_tstamp);
                rds_inc_addref(inc);
                list_add_tail(&inc->i_item, &rs->rs_recv_queue);
                __rds_wake_sk_sleep(sk);
@@ -381,7 +387,8 @@ static int rds_notify_cong(struct rds_sock *rs, struct msghdr *msghdr)
 /*
  * Receive any control messages.
  */
-static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg)
+static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg,
+                        struct rds_sock *rs)
 {
        int ret = 0;
 
@@ -392,6 +399,15 @@ static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg)
                        return ret;
        }
 
+       if ((inc->i_rx_tstamp.tv_sec != 0) &&
+           sock_flag(rds_rs_to_sk(rs), SOCK_RCVTSTAMP)) {
+               ret = put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP,
+                              sizeof(struct timeval),
+                              &inc->i_rx_tstamp);
+               if (ret)
+                       return ret;
+       }
+
        return 0;
 }
 
@@ -474,7 +490,7 @@ int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
                        msg->msg_flags |= MSG_TRUNC;
                }
 
-               if (rds_cmsg_recv(inc, msg)) {
+               if (rds_cmsg_recv(inc, msg, rs)) {
                        ret = -EFAULT;
                        goto out;
                }