From nobody Fri Nov 07 15:31:06 2025 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4d331Q4YB9z6G5RP; Fri, 07 Nov 2025 15:31:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R12" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4d331Q3vDLz3SHB; Fri, 07 Nov 2025 15:31:06 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1762529466; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=wYFpE7AhsrkpCtwWxPeXqXMJ8V+21rYXzAUI1zFl2k4=; b=EIl1sqQ9NmqRR4ts7uFu2afj8LWoSXWtoZv+MB8xyvHU6x7MRkO+FUxaEUkcU+Jue6ZceH BfYxDOpgHU6GLtyQyJTC2VDuU1/bdCFs8N5lHpDtkqTacjJqp6CMB29bjO52I+ioCnnsUe lEI4VAn6fx0cAfue1tHkaf1EMpb0sqGOigc4TfCSSQCApx/xTlNNBWPr70HSYtR8q66uNP +G2arCjJBheDXBBZEM4XamH/b6ocj9eijFztyNdKFec1FpG1NAUmYXNHKDA3O4R4lb8cYm zXRg8rSF4hjL2jhYMJ2HF1nHAE2h4VmEZR9W5RUkgtIUJdt9BhmumWu4poTqjQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1762529466; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=wYFpE7AhsrkpCtwWxPeXqXMJ8V+21rYXzAUI1zFl2k4=; b=TdamCJyqVR7gw/XzaT5HjDbBDZ3BhwqyJdJBWWbcIGR5dIf5wRfexnXYPdKFN9vh3lNWpT PjFYJgpv3zMk/8KArWcr87UbJ0N2BvF2Kcbse2WlY845Q0z31ZVMNBWc0ChemZagbHP77g zqXXyICBM9WcxTkrmSNZAVE5shcjKhveIA0DuTKrCUe9y7HJd/0CxlAcv98uCOgJbN1g1v lgPLcJL5Vsk1xunJNLESc+HzZN953HiwLpy/C9TPktyXnXuieKcjwK1TGBr2j/vqCnHRFC ZXizcDzy5nlFT/IRhgVJrUw2upaFrrbdn+l7zPPh/b7XBqsDVXKCvi9QLW/vPw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1762529466; a=rsa-sha256; cv=none; b=XJ6vFJ7nTq0uFjH17qV+HPXxHuH47EMfgk3ofpnXYtisVD3d4r08VQaRs8ISBOVARTok6/ yz1rfeOQshqaHY+qtnK9FPHCGscQ866YQ4sX+PCVWA0L/JE21pPLyXujKggEGXhVGgWWLC DIBYlsQ99zI5tfpcAyvYiabo6Jldi5duLv0FHuWi+acJD2CfFSZLKYbYlVOP18SKNdn0BQ NZlbfPdR93la0+fyY/rJGQqNg1RiyOIoMapbJU4nZqnEpo12rU6ZvMD2qkNpPHwflnrtMW ceJ3u9PBa7nCYPgSxAOGXqS0C5dqmy+WgYsz1C2mMbGMzRMqwWwImZtDbusPaA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4d331Q3N1Qz14ZJ; Fri, 07 Nov 2025 15:31:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 5A7FV6Tg058235; Fri, 7 Nov 2025 15:31:06 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 5A7FV6Wh058231; Fri, 7 Nov 2025 15:31:06 GMT (envelope-from git) Date: Fri, 7 Nov 2025 15:31:06 GMT Message-Id: <202511071531.5A7FV6Wh058231@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Michael Tuexen Subject: git: 17fb082104ee - main - tcp: improve comments in the syncache code List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: tuexen X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 17fb082104ee281365b72bd5135604cea5051df2 Auto-Submitted: auto-generated The branch main has been updated by tuexen: URL: https://cgit.FreeBSD.org/src/commit/?id=17fb082104ee281365b72bd5135604cea5051df2 commit 17fb082104ee281365b72bd5135604cea5051df2 Author: Michael Tuexen AuthorDate: 2025-11-07 15:27:56 +0000 Commit: Michael Tuexen CommitDate: 2025-11-07 15:27:56 +0000 tcp: improve comments in the syncache code Add a comment explaining why syncache entries are dropped and fix a typo in a comment. Reviewed by: rrs, glebius MFC after: 3 days Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D53564 --- sys/netinet/tcp_syncache.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/sys/netinet/tcp_syncache.c b/sys/netinet/tcp_syncache.c index fa7035771714..6c072e0fec38 100644 --- a/sys/netinet/tcp_syncache.c +++ b/sys/netinet/tcp_syncache.c @@ -535,6 +535,10 @@ syncache_timer(void *xsch) TCPSTAT_INC(tcps_sndtotal); TCPSTAT_INC(tcps_sc_retransmitted); } else { + /* + * Most likely we are memory constrained, so free + * resources. + */ syncache_drop(sc, sch); TCPSTAT_INC(tcps_sc_dropped); } @@ -734,7 +738,7 @@ syncache_unreach(struct in_conninfo *inc, tcp_seq th_seq, uint16_t port) goto done; /* - * If we've rertransmitted 3 times and this is our second error, + * If we've retransmitted 3 times and this is our second error, * we remove the entry. Otherwise, we allow it to continue on. * This prevents us from incorrectly nuking an entry during a * spurious network outage. @@ -1562,6 +1566,10 @@ syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th, TCPSTAT_INC(tcps_sndacks); TCPSTAT_INC(tcps_sndtotal); } else { + /* + * Most likely we are memory constrained, so free + * resources. + */ syncache_drop(sc, sch); TCPSTAT_INC(tcps_sc_dropped); } @@ -1747,6 +1755,9 @@ syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th, TCPSTAT_INC(tcps_sndacks); TCPSTAT_INC(tcps_sndtotal); } else { + /* + * Most likely we are memory constrained, so free resources. + */ if (sc != &scs) syncache_free(sc); TCPSTAT_INC(tcps_sc_dropped);