From patchwork Tue Apr 28 23:23:49 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 465806 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 739EF140320 for ; Wed, 29 Apr 2015 09:24:11 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="verification failed; unprotected key" header.d=google.com header.i=@google.com header.b=Ehase/ML; dkim-adsp=none (unprotected policy); dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031261AbbD1XYG (ORCPT ); Tue, 28 Apr 2015 19:24:06 -0400 Received: from mail-pa0-f74.google.com ([209.85.220.74]:34619 "EHLO mail-pa0-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031228AbbD1XYE (ORCPT ); Tue, 28 Apr 2015 19:24:04 -0400 Received: by pabli10 with SMTP id li10so963977pab.1 for ; Tue, 28 Apr 2015 16:24:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=gKdVQghYAlCIY9/xCdmve6lON1ClPlXlIXN4eMlDfpw=; b=Ehase/MLDQ9Hz1Kk5P5gjmo6vp45ZcCKUUBBFfyX8lQEPpoqVihZQG4xphZHC5kjWf f7eGZU+tUoOqyxNnjXDt/B/28CO+NL1R9DYXAMf7uUoWL6rz99aYDtPHXUN7FkmP7FZe I3LmD7feNqMd7HN7igB4BntZ3GRj/fH3ZLijgAX9awpQbUKl1SMFrB56MsQu4nDvJhA3 TQL2WVhOTVH9JxwesaQy4oKmV9RjUnhsjaVqfglbIjwzQLKaFl7viUpy47faJE6eQC31 eyk89UvVH667i5mWM4NdvfzgSdHra4RxC9DnJs8BEayM7BNo+Firk85LUfAtnckji9bR SO+A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=gKdVQghYAlCIY9/xCdmve6lON1ClPlXlIXN4eMlDfpw=; b=RzYFDAR+qR4pVMwWiJ0zgQwUEci0FHqIbTv1rLJojqah/2fxjBx519WS+LKh5LsZ5l 7lkfYaE2BYjC3BDQcStWdetG5vfLdRMt72Ug99Qk+IGA2eEnVZ/NEZc1O8IB1R0t41SA 5AafF7B5/HstGkBk33FuDNt4IlNWkWEmSqSMjy/0GyuMKmUaLkVP8CjTf3Lm52+gPjtJ Bojmx42lPQvId2ewsozVKKh1wYbp+PNM5L99xUHqx6H8cY80DqHTkwAzIC++c+E8ajsf EmHIHiP0QOhZqwlTWZGsxMHAdcfn7ejLrjos7AEHWkiiXYyR3k9N+Ykw7h7OIFABLHI7 X3mg== X-Gm-Message-State: ALoCoQlBKSDmrSPJ8LA6kd4NdXh1H90bOwXgC12XW9MBAw6Ci3HA5ke6jBiPJ9AbeXNjBD9dTCY/ X-Received: by 10.66.141.102 with SMTP id rn6mr17016794pab.43.1430263442960; Tue, 28 Apr 2015 16:24:02 -0700 (PDT) Received: from corpmail-nozzle1-2.hot.corp.google.com ([100.108.1.103]) by gmr-mx.google.com with ESMTPS id f100si1268400yhp.7.2015.04.28.16.24.02 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 28 Apr 2015 16:24:02 -0700 (PDT) Received: from manihi.mtv.corp.google.com ([172.17.131.143]) by corpmail-nozzle1-2.hot.corp.google.com with ESMTP id F1mGlxZ3.1; Tue, 28 Apr 2015 16:24:02 -0700 Received: by manihi.mtv.corp.google.com (Postfix, from userid 160623) id 273F2A0CB2; Tue, 28 Apr 2015 16:24:02 -0700 (PDT) From: Eric Dumazet To: "David S. Miller" Cc: netdev , Eric Dumazet , Eric Dumazet , Yuchung Cheng , Neal Cardwell Subject: [PATCH net-next 2/2] tcp: add TCP_CC_INFO socket option Date: Tue, 28 Apr 2015 16:23:49 -0700 Message-Id: <1430263429-4069-3-git-send-email-edumazet@google.com> X-Mailer: git-send-email 2.2.0.rc0.207.ga3a616c In-Reply-To: <1430263429-4069-1-git-send-email-edumazet@google.com> References: <1430263429-4069-1-git-send-email-edumazet@google.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 Cc: Yuchung Cheng Cc: Neal Cardwell Acked-by: Neal Cardwell Acked-by: Daniel Borkmann Acked-by: Yuchung Cheng --- include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 3b9718328d8b..937ec387276f 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 8c5cd9efebbc..1e06c75a6837 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -252,6 +252,7 @@ #include #include #include +#include #include #include #include @@ -2734,6 +2735,26 @@ 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;