From owner-dev-commits-src-main@freebsd.org Tue Feb 9 19:25:28 2021 Return-Path: Delivered-To: dev-commits-src-main@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 3DF005286EE; Tue, 9 Feb 2021 19:25:28 +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 "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4DZtCD1JkKz3jXn; Tue, 9 Feb 2021 19:25:28 +0000 (UTC) (envelope-from git@FreeBSD.org) 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 1F81C1073B; Tue, 9 Feb 2021 19:25:28 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 119JPSnC062760; Tue, 9 Feb 2021 19:25:28 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 119JPSho062759; Tue, 9 Feb 2021 19:25:28 GMT (envelope-from git) Date: Tue, 9 Feb 2021 19:25:28 GMT Message-Id: <202102091925.119JPSho062759@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Lutz Donnerhacke Subject: git: 011b7317dbb5 - main - netgraph/ng_bridge: Document staleness in multithreaded operation MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: donner X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 011b7317dbb5038a95b9b4fca050325a62f3991e Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-main@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for the main branch of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Feb 2021 19:25:28 -0000 The branch main has been updated by donner: URL: https://cgit.FreeBSD.org/src/commit/?id=011b7317dbb5038a95b9b4fca050325a62f3991e commit 011b7317dbb5038a95b9b4fca050325a62f3991e Author: Lutz Donnerhacke AuthorDate: 2021-02-09 11:32:46 +0000 Commit: Lutz Donnerhacke CommitDate: 2021-02-09 19:09:05 +0000 netgraph/ng_bridge: Document staleness in multithreaded operation In the data path of ng_bridge(4), the only value of the host struct, which needs to be modified, is the staleness, which is reset every time a frame is received. It's save to leave the code as it is. This patch is part of a series to make ng_bridge(4) multithreaded. Reviewed by: kp MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D28546 --- sys/netgraph/ng_bridge.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/sys/netgraph/ng_bridge.c b/sys/netgraph/ng_bridge.c index 6e3f993d591b..29ab2c715aa7 100644 --- a/sys/netgraph/ng_bridge.c +++ b/sys/netgraph/ng_bridge.c @@ -739,7 +739,10 @@ ng_bridge_rcvdata(hook_p hook, item_p item) /* Look up packet's source Ethernet address in hashtable */ if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) { - /* Update time since last heard from this host */ + /* Update time since last heard from this host. + * This is safe without locking, because it's + * the only operation during shared access. + */ host->staleness = 0; /* Did host jump to a different link? */