From owner-svn-src-all@freebsd.org Wed Aug 26 12:50:58 2020 Return-Path: Delivered-To: svn-src-all@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 76F2D3D4373; Wed, 26 Aug 2020 12:50:58 +0000 (UTC) (envelope-from mjg@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 "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Bc5M62dSBz3yKP; Wed, 26 Aug 2020 12:50:58 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 264E813078; Wed, 26 Aug 2020 12:50:58 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 07QCowgm024941; Wed, 26 Aug 2020 12:50:58 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 07QCow1S024940; Wed, 26 Aug 2020 12:50:58 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <202008261250.07QCow1S024940@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Wed, 26 Aug 2020 12:50:58 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r364812 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 364812 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 26 Aug 2020 12:50:58 -0000 Author: mjg Date: Wed Aug 26 12:50:57 2020 New Revision: 364812 URL: https://svnweb.freebsd.org/changeset/base/364812 Log: cache: only evict negative entries on CREATE when ISLASTCN is set Modified: head/sys/kern/vfs_cache.c Modified: head/sys/kern/vfs_cache.c ============================================================================== --- head/sys/kern/vfs_cache.c Wed Aug 26 12:50:10 2020 (r364811) +++ head/sys/kern/vfs_cache.c Wed Aug 26 12:50:57 2020 (r364812) @@ -1398,15 +1398,17 @@ retry: return (-1); negative_success: if (__predict_false(cnp->cn_nameiop == CREATE)) { - counter_u64_add(numnegzaps, 1); - error = cache_zap_locked_vnode(ncp, dvp); - if (__predict_false(error != 0)) { - zap_and_exit_bucket_fail2++; - cache_maybe_yield(); - goto retry; + if (cnp->cn_flags & ISLASTCN) { + counter_u64_add(numnegzaps, 1); + error = cache_zap_locked_vnode(ncp, dvp); + if (__predict_false(error != 0)) { + zap_and_exit_bucket_fail2++; + cache_maybe_yield(); + goto retry; + } + cache_free(ncp); + return (0); } - cache_free(ncp); - return (0); } SDT_PROBE2(vfs, namecache, lookup, hit__negative, dvp, ncp->nc_name); @@ -1603,15 +1605,17 @@ retry: negative_success: /* We found a negative match, and want to create it, so purge */ if (__predict_false(cnp->cn_nameiop == CREATE)) { - counter_u64_add(numnegzaps, 1); - error = cache_zap_rlocked_bucket(ncp, cnp, hash, blp); - if (__predict_false(error != 0)) { - zap_and_exit_bucket_fail2++; - cache_maybe_yield(); - goto retry; + if (cnp->cn_flags & ISLASTCN) { + counter_u64_add(numnegzaps, 1); + error = cache_zap_locked_vnode(ncp, dvp); + if (__predict_false(error != 0)) { + zap_and_exit_bucket_fail2++; + cache_maybe_yield(); + goto retry; + } + cache_free(ncp); + return (0); } - cache_free(ncp); - return (0); } SDT_PROBE2(vfs, namecache, lookup, hit__negative, dvp, ncp->nc_name); @@ -1658,13 +1662,6 @@ cache_lookup(struct vnode *dvp, struct vnode **vpp, st return (0); } - /* - * TODO: we only fallback becasue if a negative entry is found it will - * need to be purged. - */ - if (cnp->cn_nameiop == CREATE) - goto out_fallback; - hash = cache_get_hash(cnp->cn_nameptr, cnp->cn_namelen, dvp); vfs_smr_enter(); @@ -1723,6 +1720,13 @@ cache_lookup(struct vnode *dvp, struct vnode **vpp, st return (-1); negative_success: + if (__predict_false(cnp->cn_nameiop == CREATE)) { + if (cnp->cn_flags & ISLASTCN) { + vfs_smr_exit(); + goto out_fallback; + } + } + SDT_PROBE2(vfs, namecache, lookup, hit__negative, dvp, ncp->nc_name); cache_out_ts(ncp, tsp, ticksp); counter_u64_add(numneghits, 1);