From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 710EB4E819E; Thu, 8 Jan 2026 14:19:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767881992; cv=none; b=l5H8rRNRi+njebvKGF7CKkaB+cve0IuIFc9xF7LIalOuvHI9FP3zVCeWKAz3d5eMlPm0YmT9qf+sZHUokGApyd92XecdwSd4WFM/676JEgTG016hYnbGfr2OxP3LiIfw3q50LVex3X9fTlqHBK+75IbDGXZhzjwARkppG05zBrg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767881992; c=relaxed/simple; bh=pgFo/tGly54ijlfTPPtxx0Ky8wb8MMinxNhrt4wuMLg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=cC4rPmZYLTBSvaaEzOfToN0yXD0xWt7jPEwERbQkDphYs6t5NgjD4mbBKltJ1Fe4Nis4dox3F619ugrna98wB66uf3WqsHFqy0C0SaEUi6BAlREAbXUr3kpLKDjXu6EERS+YRST0Hqu42FuFLUOcd3HAeMxdUySeUMPZhNserVs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=lst.de; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=HCkUV5Sg; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="HCkUV5Sg" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:In-Reply-To:References; bh=47j3Vb5ECJCThNE4hZUuOAtfhlxTrOYUcu9LaYfkCP0=; b=HCkUV5Sg9RjiYn4vXDrQU9X8X2 QN7lpU67efTqRh1BaVJtEpKYMQAxG7T0N5995XKnZJk7w2W6cfF7OalQFG+1xpn4iCS1mLCF8LFZU gI2xKmgSvoXaJnySBF9YEhWtKLaWW7n6Y8WsCHdLazXAFwFVgQFsrhIxgACJfaKplPExgcdHw01Kq Ke4GwPEVve9HwaXeITYANFM+28/9dKysmfdekPnByN9rEJlzWGQfqqhw/sYk5H/myvcdC4/dP73NO EnAdF+bwO9giTfj+kY8VlOmqBYEyM2N4eNeUEjVZQAm6jkNPHOIPZEmQEn0ZAp410vM3yx9JmCZ62 jjcnpyIg==; Received: from 2a02-8389-2341-5b80-d601-7564-c2e0-491c.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:d601:7564:c2e0:491c] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vdqrX-0000000HJ7f-3drf; Thu, 08 Jan 2026 14:19:44 +0000 From: Christoph Hellwig To: Christian Brauner Cc: Al Viro , David Sterba , Jan Kara , Mike Marshall , Martin Brandenburg , Carlos Maiolino , Stefan Roesch , Jeff Layton , OGAWA Hirofumi , Trond Myklebust , Anna Schumaker , linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, gfs2@lists.linux.dev, io-uring@vger.kernel.org, devel@lists.orangefs.org, linux-unionfs@vger.kernel.org, linux-mtd@lists.infradead.org, linux-xfs@vger.kernel.org, linux-nfs@vger.kernel.org Subject: re-enable IOCB_NOWAIT writes to files v6 Date: Thu, 8 Jan 2026 15:19:00 +0100 Message-ID: <20260108141934.2052404-1-hch@lst.de> X-Mailer: git-send-email 2.47.3 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Hi all, commit 66fa3cedf16a ("fs: Add async write file modification handling.") effectively disabled IOCB_NOWAIT writes as timestamp updates currently always require blocking, and the modern timestamp resolution means we always update timestamps. This leads to a lot of context switches from applications using io_uring to submit file writes, making it often worse than using the legacy aio code that is not using IOCB_NOWAIT. This series allows non-blocking updates for lazytime if the file system supports it, and adds that support for XFS. Changes since v5: - sample ctime before calling inode_set_ctime_current - fix a mild bisection hazard in fat Changes since v4: - replace the S_* flags with an enum indicating either access or modification time updates to make the logic less fragile and to fix a bug in the previous version Changes since v3: - fix was_dirty_time handling in __mark_inode_dirty for the racy flag update case - refactor inode_update_timestamps to make the lazytime vs blocking logical more clear - allow non-blocking timestamp updates for fat Changes since v2: - drop patches merged upstream - adjust for the inode state accesors - keep a check in __writeback_single_inode instead of exercising potentially undefined behavior - more spelling fixes Changes since v1: - more regular numbering of the S_* flags - fix XFS to actually not block - don't ignore the generic_update_time return value in file_update_time_flags - fix the sync_lazytime return value - fix an out of data comment in btrfs - fix a race that would update i_version before returning -EAGAIN in XFS Diffstat: Documentation/filesystems/locking.rst | 2 Documentation/filesystems/vfs.rst | 6 + fs/btrfs/inode.c | 8 +- fs/fs-writeback.c | 33 +++++++--- fs/gfs2/inode.c | 6 + fs/inode.c | 111 +++++++++++++++++++++------------- fs/internal.h | 3 fs/nfs/inode.c | 4 - fs/orangefs/inode.c | 5 + fs/overlayfs/inode.c | 2 fs/sync.c | 4 - fs/ubifs/file.c | 13 ++- fs/xfs/xfs_iops.c | 34 +++++++++- fs/xfs/xfs_super.c | 29 -------- include/linux/fs.h | 27 ++++++-- include/trace/events/writeback.h | 6 - 16 files changed, 182 insertions(+), 111 deletions(-)