From owner-dev-commits-src-branches@freebsd.org Mon Feb 1 12:40:35 2021 Return-Path: Delivered-To: dev-commits-src-branches@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 C45C64FE8DE; Mon, 1 Feb 2021 12:40:35 +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 4DTnbl4xfmz3DwB; Mon, 1 Feb 2021 12:40:35 +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 97F651B693; Mon, 1 Feb 2021 12:40:35 +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 111CeZUN094700; Mon, 1 Feb 2021 12:40:35 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 111CeZjh094699; Mon, 1 Feb 2021 12:40:35 GMT (envelope-from git) Date: Mon, 1 Feb 2021 12:40:35 GMT Message-Id: <202102011240.111CeZjh094699@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mateusz Guzik Subject: git: ba0689009b71 - stable/13 - cache: add back target entry on rename MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: mjg X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: ba0689009b712c558f4ec2b28202a4e45c5bab91 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-branches@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commits to the stable branches of the FreeBSD src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 01 Feb 2021 12:40:35 -0000 The branch stable/13 has been updated by mjg: URL: https://cgit.FreeBSD.org/src/commit/?id=ba0689009b712c558f4ec2b28202a4e45c5bab91 commit ba0689009b712c558f4ec2b28202a4e45c5bab91 Author: Mateusz Guzik AuthorDate: 2021-01-23 17:21:42 +0000 Commit: Mateusz Guzik CommitDate: 2021-02-01 12:39:15 +0000 cache: add back target entry on rename (cherry picked from commit 02ec31bdf60fa3a8530544cb3c8c4ec1df6cde0d) --- sys/kern/vfs_cache.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c index 770c8ebf061b..03bafc75acaa 100644 --- a/sys/kern/vfs_cache.c +++ b/sys/kern/vfs_cache.c @@ -367,6 +367,10 @@ static bool __read_frequently cache_fast_revlookup = true; SYSCTL_BOOL(_vfs, OID_AUTO, cache_fast_revlookup, CTLFLAG_RW, &cache_fast_revlookup, 0, ""); +static bool __read_mostly cache_rename_add = true; +SYSCTL_BOOL(_vfs, OID_AUTO, cache_rename_add, CTLFLAG_RW, + &cache_rename_add, 0, ""); + static u_int __exclusive_cache_line neg_cycle; #define ncneghash 3 @@ -2731,6 +2735,21 @@ cache_vop_rename(struct vnode *fdvp, struct vnode *fvp, struct vnode *tdvp, } else { cache_remove_cnp(tdvp, tcnp); } + + /* + * TODO + * + * Historically renaming was always purging all revelang entries, + * but that's quite wasteful. In particular turns out that in many cases + * the target file is immediately accessed after rename, inducing a cache + * miss. + * + * Recode this to reduce relocking and reuse the existing entry (if any) + * instead of just removing it above and allocating a new one here. + */ + if (cache_rename_add) { + cache_enter(tdvp, fvp, tcnp); + } } void