From patchwork Tue Sep 28 21:46:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Wang X-Patchwork-Id: 12523911 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE9F1C433F5 for ; Tue, 28 Sep 2021 21:47:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF9366127A for ; Tue, 28 Sep 2021 21:47:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242992AbhI1Vsl (ORCPT ); Tue, 28 Sep 2021 17:48:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41606 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242929AbhI1Vsf (ORCPT ); Tue, 28 Sep 2021 17:48:35 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62594C061753 for ; Tue, 28 Sep 2021 14:46:53 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id q8-20020a056902150800b005b640f67812so649291ybu.8 for ; Tue, 28 Sep 2021 14:46:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=CvGJ4Z6Bljun4/eGYY7fseGY0GSY3h9OiPiupWWA5tM=; b=Lze0PfYSKoHzEG5gYm69AnCJ3QP3NVt3LpHVCa4RCR3dMtiWBjwf3IfyxCDEtPmCS7 QWQDaraGXxbClPJIVDR/SYrtLwULRVmEJPm7bDPuTs7DGs94f0wunIccg5wrPuy2N3s9 X0IbcEoDTlN7gnDTm4vQoze7yAvjKDWhTUOzffjVtNrobnJGlSMyho3Y1IsRe/hZQkQK FQL/Rnwtdwk6a0xNgiCgTOg/ge4nQ1m6B1GBkSiy7RakrlPZcN1TnG+udIG+0d6Dl0rt ClEMtnUfzLJUYKl86TwZNCb5BoZWyMY2lzjyc3VrsxFC2a20qh3X+P9EixaEmog0vC0y rojg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=CvGJ4Z6Bljun4/eGYY7fseGY0GSY3h9OiPiupWWA5tM=; b=LmwS2rg5MM/zvFPsbQwwzf96TUJUfXzszjmT5DckYdy2+aj1RfCFwsZBMANsuTGuwD 3xeDjp4mjoz6WmR9xtV9ib0rRCtD64vb3g2w/16BpG19ZSR/iEaiKs6VmwQeWZcKVqbf qf75Wi1ZGi2fBpE9rAb1Ym8MpFBMShaCAHoBxikheKdBpxYePX/vaq98Ro+61256SbgI 4L3vzUcB+dJZ2eB0aJCw2dNDii+Y4zVhAd121aNXU0XGEkW4HeBn5Syjoz3kbqqnIEMb t9DIUXNb/el0WFmdTgyLWyNks/Mre04EU/NM4kpilI0c+XWjD0IRLP9eLXyc6RGFLs6k oCBw== X-Gm-Message-State: AOAM533ZT2+MCN9gpGWlfuoB6VnzjAM5nW4pC+Oq9bsYUz+PVNdewIPo HgveROodUpg8GOT2KJcc2mBKpvyNg90= X-Google-Smtp-Source: ABdhPJxI61vdVZfTksJ4YAXnqjd6cddULBil+rmmgVNujyBhFt/DE0YXfmyLqzv9UK1LGmDiEDtzA8zAkrc= X-Received: from weiwan.svl.corp.google.com ([2620:15c:2c4:201:5d42:81b8:4b7f:efe2]) (user=weiwan job=sendgmr) by 2002:a05:6902:1141:: with SMTP id p1mr10035886ybu.0.1632865612675; Tue, 28 Sep 2021 14:46:52 -0700 (PDT) Date: Tue, 28 Sep 2021 14:46:43 -0700 In-Reply-To: <20210928214643.3300692-1-weiwan@google.com> Message-Id: <20210928214643.3300692-4-weiwan@google.com> Mime-Version: 1.0 References: <20210928214643.3300692-1-weiwan@google.com> X-Mailer: git-send-email 2.33.0.685.g46640cef36-goog Subject: [PATCH v2 net-next 3/3] tcp: adjust rcv_ssthresh according to sk_reserved_mem From: Wei Wang To: Jakub Kicinski , "'David S . Miller'" , netdev@vger.kernel.org Cc: Shakeel Butt , Eric Dumazet Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org When user sets SO_RESERVE_MEM socket option, in order to utilize the reserved memory when in memory pressure state, we adjust rcv_ssthresh according to the available reserved memory for the socket, instead of using 4 * advmss always. Signed-off-by: Wei Wang Signed-off-by: Eric Dumazet --- include/net/tcp.h | 11 +++++++++++ net/ipv4/tcp_input.c | 12 ++++++++++-- net/ipv4/tcp_output.c | 3 +-- 3 files changed, 22 insertions(+), 4 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 32cf6c01f403..4c2898ac6569 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1421,6 +1421,17 @@ static inline int tcp_full_space(const struct sock *sk) return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf)); } +static inline void tcp_adjust_rcv_ssthresh(struct sock *sk) +{ + int unused_mem = sk_unused_reserved_mem(sk); + struct tcp_sock *tp = tcp_sk(sk); + + tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U * tp->advmss); + if (unused_mem) + tp->rcv_ssthresh = max_t(u32, tp->rcv_ssthresh, + tcp_win_from_space(sk, unused_mem)); +} + void tcp_cleanup_rbuf(struct sock *sk, int copied); /* We provision sk_rcvbuf around 200% of sk_rcvlowat. diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 06020395cc8d..246ab7b5e857 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -500,8 +500,11 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb, room = min_t(int, tp->window_clamp, tcp_space(sk)) - tp->rcv_ssthresh; + if (room <= 0) + return; + /* Check #1 */ - if (room > 0 && !tcp_under_memory_pressure(sk)) { + if (!tcp_under_memory_pressure(sk)) { unsigned int truesize = truesize_adjust(adjust, skb); int incr; @@ -518,6 +521,11 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb, tp->rcv_ssthresh += min(room, incr); inet_csk(sk)->icsk_ack.quick |= 1; } + } else { + /* Under pressure: + * Adjust rcv_ssthresh according to reserved mem + */ + tcp_adjust_rcv_ssthresh(sk); } } @@ -5345,7 +5353,7 @@ static int tcp_prune_queue(struct sock *sk) if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) tcp_clamp_window(sk); else if (tcp_under_memory_pressure(sk)) - tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U * tp->advmss); + tcp_adjust_rcv_ssthresh(sk); if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) return 0; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index fdc39b4fbbfa..3a01e5593a17 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2967,8 +2967,7 @@ u32 __tcp_select_window(struct sock *sk) icsk->icsk_ack.quick = 0; if (tcp_under_memory_pressure(sk)) - tp->rcv_ssthresh = min(tp->rcv_ssthresh, - 4U * tp->advmss); + tcp_adjust_rcv_ssthresh(sk); /* free_space might become our new window, make sure we don't * increase it due to wscale.