From owner-dev-commits-src-all@freebsd.org Thu May 20 15:27:44 2021 Return-Path: Delivered-To: dev-commits-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 2A0FE641B35; Thu, 20 May 2021 15:27:44 +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 4FmDBm0lFcz4frd; Thu, 20 May 2021 15:27:44 +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 01C3E285D0; Thu, 20 May 2021 15:27:44 +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 14KFRhql036649; Thu, 20 May 2021 15:27:43 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 14KFRhEL036648; Thu, 20 May 2021 15:27:43 GMT (envelope-from git) Date: Thu, 20 May 2021 15:27:43 GMT Message-Id: <202105201527.14KFRhEL036648@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: f17a5900850b - main - ufs: Avoid M_WAITOK allocations when building a dirhash MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: f17a5900850b4d449a91cbe9c61dfb62373c3cd1 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 20 May 2021 15:27:44 -0000 The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=f17a5900850b4d449a91cbe9c61dfb62373c3cd1 commit f17a5900850b4d449a91cbe9c61dfb62373c3cd1 Author: Don Morris AuthorDate: 2021-05-20 14:54:38 +0000 Commit: Mark Johnston CommitDate: 2021-05-20 15:25:45 +0000 ufs: Avoid M_WAITOK allocations when building a dirhash At this point the directory's vnode lock is held, so blocking while waiting for free pages makes the system more susceptible to deadlock in low memory conditions. This is particularly problematic on NUMA systems as UMA currently implements a strict first-touch policy. ufsdirhash_build() already uses M_NOWAIT for other allocations and already handled failures for the block array allocation, so just convert to M_NOWAIT. PR: 253992 Reviewed by: markj, mckusick, vangyzen MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D29045 --- sys/ufs/ufs/ufs_dirhash.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sys/ufs/ufs/ufs_dirhash.c b/sys/ufs/ufs/ufs_dirhash.c index 13094b5a1c97..d1e1bed0bde4 100644 --- a/sys/ufs/ufs/ufs_dirhash.c +++ b/sys/ufs/ufs/ufs_dirhash.c @@ -108,7 +108,7 @@ static uma_zone_t ufsdirhash_zone; #define DIRHASHLIST_LOCK() mtx_lock(&ufsdirhash_mtx) #define DIRHASHLIST_UNLOCK() mtx_unlock(&ufsdirhash_mtx) -#define DIRHASH_BLKALLOC_WAITOK() uma_zalloc(ufsdirhash_zone, M_WAITOK) +#define DIRHASH_BLKALLOC() uma_zalloc(ufsdirhash_zone, M_NOWAIT) #define DIRHASH_BLKFREE(ptr) uma_zfree(ufsdirhash_zone, (ptr)) #define DIRHASH_ASSERT_LOCKED(dh) \ sx_assert(&(dh)->dh_lock, SA_LOCKED) @@ -425,7 +425,7 @@ ufsdirhash_build(struct inode *ip) if (dh->dh_blkfree == NULL) goto fail; for (i = 0; i < narrays; i++) { - if ((dh->dh_hash[i] = DIRHASH_BLKALLOC_WAITOK()) == NULL) + if ((dh->dh_hash[i] = DIRHASH_BLKALLOC()) == NULL) goto fail; for (j = 0; j < DH_NBLKOFF; j++) dh->dh_hash[i][j] = DIRHASH_EMPTY;