From 62748f32d501f5d3712a7c372bbb92abc7c62bc7 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 24 Sep 2013 08:20:52 -0700 Subject: net: introduce SO_MAX_PACING_RATE As mentioned in commit afe4fd062416b ("pkt_sched: fq: Fair Queue packet scheduler"), this patch adds a new socket option. SO_MAX_PACING_RATE offers the application the ability to cap the rate computed by transport layer. Value is in bytes per second. u32 val = 1000000; setsockopt(sockfd, SOL_SOCKET, SO_MAX_PACING_RATE, &val, sizeof(val)); To be effectively paced, a flow must use FQ packet scheduler. Note that a packet scheduler takes into account the headers for its computations. The effective payload rate depends on MSS and retransmits if any. I chose to make this pacing rate a SOL_SOCKET option instead of a TCP one because this can be used by other protocols. Signed-off-by: Eric Dumazet Cc: Steinar H. Gunderson Cc: Michael Kerrisk Signed-off-by: David S. Miller --- include/net/sock.h | 1 + include/uapi/asm-generic/socket.h | 2 ++ 2 files changed, 3 insertions(+) (limited to 'include') diff --git a/include/net/sock.h b/include/net/sock.h index 4625d2e..240aa3f 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -363,6 +363,7 @@ struct sock { int sk_wmem_queued; gfp_t sk_allocation; u32 sk_pacing_rate; /* bytes per second */ + u32 sk_max_pacing_rate; netdev_features_t sk_route_caps; netdev_features_t sk_route_nocaps; int sk_gso_type; diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index f04b69b..38f14d0 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -78,4 +78,6 @@ #define SO_BUSY_POLL 46 +#define SO_MAX_PACING_RATE 47 + #endif /* __ASM_GENERIC_SOCKET_H */ -- cgit v1.1