diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-04-28 16:23:49 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-04-29 17:10:38 -0400 |
| commit | 6e9250f59ef9efb932c84850cd221f22c2a03c4a (patch) | |
| tree | 8492e1b4724aa12b31675b45e3bb681f860213f0 | |
| parent | 64f40ff5bbdb1b679fb3c4dbc8230d6517d2b8dc (diff) | |
tcp: add TCP_CC_INFO socket option
Some Congestion Control modules can provide per flow information,
but current way to get this information is to use netlink.
Like TCP_INFO, let's add TCP_CC_INFO so that applications can
issue a getsockopt() if they have a socket file descriptor,
instead of playing complex netlink games.
Sample usage would be :
union tcp_cc_info info;
socklen_t len = sizeof(info);
if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/uapi/linux/tcp.h | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp.c | 21 |
2 files changed, 22 insertions, 0 deletions
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index a48f93f3207b..faa72f4fa547 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -112,6 +112,7 @@ enum { #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ #define TCP_TIMESTAMP 24 #define TCP_NOTSENT_LOWAT 25 /* limit number of unsent bytes in write queue */ +#define TCP_CC_INFO 26 /* Get Congestion Control (optional) info */ struct tcp_repair_opt { __u32 opt_code; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 99fcc0b22c92..46efa03d2b11 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -252,6 +252,7 @@ #include <linux/types.h> #include <linux/fcntl.h> #include <linux/poll.h> +#include <linux/inet_diag.h> #include <linux/init.h> #include <linux/fs.h> #include <linux/skbuff.h> @@ -2739,6 +2740,26 @@ static int do_tcp_getsockopt(struct sock *sk, int level, return -EFAULT; return 0; } + case TCP_CC_INFO: { + const struct tcp_congestion_ops *ca_ops; + union tcp_cc_info info; + size_t sz = 0; + int attr; + + if (get_user(len, optlen)) + return -EFAULT; + + ca_ops = icsk->icsk_ca_ops; + if (ca_ops && ca_ops->get_info) + sz = ca_ops->get_info(sk, ~0U, &attr, &info); + + len = min_t(unsigned int, len, sz); + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, &info, len)) + return -EFAULT; + return 0; + } case TCP_QUICKACK: val = !icsk->icsk_ack.pingpong; break; |