From owner-svn-src-head@freebsd.org Tue Sep 17 17:44:51 2019 Return-Path: Delivered-To: svn-src-head@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 928E012A56C; Tue, 17 Sep 2019 17:44:51 +0000 (UTC) (envelope-from mckusick@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) server-signature RSA-PSS (4096 bits) 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 46Xr8z3KZ9z4HtD; Tue, 17 Sep 2019 17:44:51 +0000 (UTC) (envelope-from mckusick@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 37665C096; Tue, 17 Sep 2019 17:44:51 +0000 (UTC) (envelope-from mckusick@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x8HHipLd019777; Tue, 17 Sep 2019 17:44:51 GMT (envelope-from mckusick@FreeBSD.org) Received: (from mckusick@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x8HHipJ4019776; Tue, 17 Sep 2019 17:44:51 GMT (envelope-from mckusick@FreeBSD.org) Message-Id: <201909171744.x8HHipJ4019776@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mckusick set sender to mckusick@FreeBSD.org using -f From: Kirk McKusick Date: Tue, 17 Sep 2019 17:44:51 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r352453 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: mckusick X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 352453 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Sep 2019 17:44:51 -0000 Author: mckusick Date: Tue Sep 17 17:44:50 2019 New Revision: 352453 URL: https://svnweb.freebsd.org/changeset/base/352453 Log: The VFS-level clustering code collects together sequential blocks by issuing delayed-writes (bdwrite()) until a non-sequential block is written or the maximum cluster size is reached. At that point it collects the delayed buffers together (using bread()) to write them in a single operation. The assumption was that since we just looked at them they will still be in memory so there is no need to check for a read error from bread(). Very occationally (apparently every 10-hours or so when being pounded by Peter Holm's tests) this assumption is wrong. The fix is to check for errors from bread() and fail the cluster write thus falling back to the default individual flushing of any still dirty buffers. Reported by: Peter Holm and Chuck Silvers Reviewed by: kib MFC after: 3 days Modified: head/sys/kern/vfs_cluster.c Modified: head/sys/kern/vfs_cluster.c ============================================================================== --- head/sys/kern/vfs_cluster.c Tue Sep 17 17:28:44 2019 (r352452) +++ head/sys/kern/vfs_cluster.c Tue Sep 17 17:44:50 2019 (r352453) @@ -718,6 +718,14 @@ cluster_write(struct vnode *vp, struct buf *bp, u_quad struct cluster_save *buflist; buflist = cluster_collectbufs(vp, bp, gbflags); + if (buflist == NULL) { + /* + * Cluster build failed so just write + * it now. + */ + bawrite(bp); + return; + } endbp = &buflist->bs_children [buflist->bs_nchildren - 1]; if (VOP_REALLOCBLKS(vp, buflist)) { @@ -1056,7 +1064,7 @@ cluster_collectbufs(struct vnode *vp, struct buf *last struct cluster_save *buflist; struct buf *bp; daddr_t lbn; - int i, len; + int i, j, len, error; len = vp->v_lastw - vp->v_cstart + 1; buflist = malloc(sizeof(struct buf *) * (len + 1) + sizeof(*buflist), @@ -1064,8 +1072,18 @@ cluster_collectbufs(struct vnode *vp, struct buf *last buflist->bs_nchildren = 0; buflist->bs_children = (struct buf **) (buflist + 1); for (lbn = vp->v_cstart, i = 0; i < len; lbn++, i++) { - (void)bread_gb(vp, lbn, last_bp->b_bcount, NOCRED, + error = bread_gb(vp, lbn, last_bp->b_bcount, NOCRED, gbflags, &bp); + if (error != 0) { + /* + * If read fails, release collected buffers + * and return failure. + */ + for (j = 0; j < i; j++) + brelse(buflist->bs_children[j]); + free(buflist, M_SEGMENT); + return (NULL); + } buflist->bs_children[i] = bp; if (bp->b_blkno == bp->b_lblkno) VOP_BMAP(vp, bp->b_lblkno, NULL, &bp->b_blkno,