From patchwork Mon Jul 1 10:26:36 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 13717828 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 8BC5612C486; Mon, 1 Jul 2024 10:27:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719829628; cv=none; b=nr907TUxMiIPiDM8qxVmudbKR1475DJ7J+kZ9xzTJWobOJRJYwLNRMw9+qleiHt4r2FTGooGgKYm6rRiE2lD5pzYeBBKKgmosMWQtWj7sVeT/fGUZWBDLmqbqnHEAyE1+QtGejTZOLVr29UyHNuwTTRTnXcBy9Hp5zz9x03hLwE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719829628; c=relaxed/simple; bh=X6JnNaUpmLXm/etsj1wjIh6Yp85tWQSB7sG1ZkO5uUo=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=aNBvx+6AygEdqOb1vQs/mPAwO0Z8X8LlColdthzknqCVMPHASWprmI1fstOCuJsxNDWK2HAPGyTQylF+r9KjN4f7eOIs7KyGVrtFJADmRwzWEJfzc4fYMFFoDGHvwBv9C/jJvGkulPO3BtiafOGJd/W3i/w54ZIyf8NNd1zwTYk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Vf+KOvFJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Vf+KOvFJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10A2DC116B1; Mon, 1 Jul 2024 10:27:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719829628; bh=X6JnNaUpmLXm/etsj1wjIh6Yp85tWQSB7sG1ZkO5uUo=; h=From:Subject:Date:To:Cc:From; b=Vf+KOvFJKBw679ZYAgmsH0RLuGYp8IAiSlCCZUhsTO4bKK7aVVnIt6i4tns2GxcVc arXIZflCj58WmK6HjROQJKCEmt3cQ5z0Hzi3pn3cztxRDFM9AW3TTN05aRVRbzfTIP nb/Zx0ZvRRprqg1+Pe8fWPIbcD8w30t2kT6oAPo+uHh9tj3fWC6GkC1S99hRvIETG8 521TVFm4Rxsi2Kpi4RFWUdZBsF5bKnOYBn+8q1ndAmtmtM2N3/ewIfHvBZfYQtQ7KW HZaynh8qe10p4ksacSS8KtMrPUEca2HAktvREYgJJmRJZftrOhVHQ9Oj0ZFkjFs9uC 8nHV+WEk81uqA== From: Jeff Layton Subject: [PATCH v2 00/11] fs: multigrain timestamp redux Date: Mon, 01 Jul 2024 06:26:36 -0400 Message-Id: <20240701-mgtime-v2-0-19d412a940d9@kernel.org> Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAFyEgmYC/2XMQQ7CIBCF4as0sxYDaBt05T1MF7UMdKKFZmiIp uHuYrcu/5eXb4OETJjg2mzAmClRDDX0oYFxGoJHQbY2aKnPstOdmP1KM4p2tEY+lLFGSajnhdH Re4fufe2J0hr5s7tZ/dY/IishxaDM5dRqK51xtydywNcxsoe+lPIFCXxMlJ0AAAA= To: Alexander Viro , Christian Brauner , Jan Kara , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Chandan Babu R , "Darrick J. Wong" , Theodore Ts'o , Andreas Dilger , Chris Mason , Josef Bacik , David Sterba , Hugh Dickins , Andrew Morton Cc: Andi Kleen , kernel-team@fb.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org, Jeff Layton X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3820; i=jlayton@kernel.org; h=from:subject:message-id; bh=X6JnNaUpmLXm/etsj1wjIh6Yp85tWQSB7sG1ZkO5uUo=; b=owEBbQKS/ZANAwAIAQAOaEEZVoIVAcsmYgBmgoRw4WRZGASUb0ntKxZvyqMtYMkx8cPpzxKSo 7jHqLZ2ou6JAjMEAAEIAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCZoKEcAAKCRAADmhBGVaC FRklD/0V9mb072IqdAyazN2How8Y2mDXc3TC/CKJ07/XI2o0+GsYhF4MwAHLt4dLmtP0m5lVEYt IXSS117t5QAbroXjMGDO78L/ngFJ6XHQNs8ApzjMPUa8wiawbeiKGEYtqgRm0+QcHsSkXtOKbfN /YpUKYMts3Zt4XXHBcfdJNv2QCNem83SoduUEY5ZGw+Cm3Zi428oPzX4zNx+KGveuc0atwcVkoM bNcs4Ua8HzyOOjnAZPcbSyLDv7nl4Lp8AeF86Pzg9s/TpY1We1cUclLV4H0DBoGVSc6rYrn73IJ F6XwQI5jldA2SxQpsuUq3Q9fRBGLIvU82LiSsJ6TuneSFb/nlLahtrbfTsFZKeBv1T8AtN/Bm3g 7JF8I8BESppicGDpFegi78JzwQvXq9QqPEeQoL7aFSVVBjDjlqz5kGT+3dZn5T6RoKRMPqNiTGY jIBsiFOWOR2qM8jpIb5mwYfHjSJSVf0FYhYrzNiOBhC60Mo5QrsyK73HTwf0ouEznjygtcaOgqs FevfDb09sW8WOF9igWYRK8bqpYkDbxPGVkflRLNElGxBooBGRokJsXnKOj63BWkqpAmZxct3dR6 zcO9QewsnTTV5FQuOh/q1SzW+lOoa+eIAOqMTV8bsC+bXen4HUI4jXfhPlhbAOHNxurzh0M7nLT mBgV2UQww4zEPtQ== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 This set is essentially unchanged from the last one, aside from the new file in Documentation/. I had a review comment from Andi Kleen suggesting that the ctime_floor should be per time_namespace, but I think that's incorrect as the realtime clock is not namespaced. At LSF/MM this year, we had a discussion about the inode change attribute. At the time I mentioned that I thought I could salvage the multigrain timestamp work that had to be reverted last year [1]. That version had to be reverted because it was possible for a file to get a coarse grained timestamp that appeared to be earlier than another file that had recently gotten a fine-grained stamp. This version corrects the problem by establishing a per-time_namespace ctime_floor value that should prevent this from occurring. In the above situation that was problematic before, the two files might end up with the same timestamp value, but they won't appear to have been modified in the wrong order. That problem was discovered by the test-stat-time gnulib test. Note that that test still fails on multigrain timestamps, but that's because its method of determining the minimum delay that will show a timestamp change will no longer work with multigrain timestamps. I have a patch to change the testcase to use a different method that I've posted to the bug-gnulib mailing list. The big question with this set is whether the performance will be suitable. The testing I've done seems to show performance parity with multigrain timestamps enabled, but it's hard to rule this out regressing some workload. This set is based on top of Christian's vfs.misc branch (which has the earlier change to track inode timestamps as discrete integers). If there are no major objections, I'd like to let this soak in linux-next for a bit to see if any problems shake out. [1]: https://lore.kernel.org/linux-fsdevel/20230807-mgctime-v7-0-d1dec143a704@kernel.org/ Signed-off-by: Jeff Layton Reviewed-by: Josef Bacik --- Changes in v2: - Added Documentation file - Link to v1: https://lore.kernel.org/r/20240626-mgtime-v1-0-a189352d0f8f@kernel.org --- Jeff Layton (11): fs: turn inode ctime fields into a single ktime_t fs: uninline inode_get_ctime and inode_set_ctime_to_ts fs: tracepoints for inode_needs_update_time and inode_set_ctime_to_ts fs: add infrastructure for multigrain timestamps fs: add percpu counters to count fine vs. coarse timestamps fs: have setattr_copy handle multigrain timestamps appropriately xfs: switch to multigrain timestamps ext4: switch to multigrain timestamps btrfs: convert to multigrain timestamps tmpfs: add support for multigrain timestamps Documentation: add a new file documenting multigrain timestamps Documentation/filesystems/multigrain-ts.rst | 126 ++++++++++++++++ fs/attr.c | 52 ++++++- fs/btrfs/file.c | 25 +--- fs/btrfs/super.c | 3 +- fs/ext4/super.c | 2 +- fs/inode.c | 221 +++++++++++++++++++++++++--- fs/stat.c | 39 ++++- fs/xfs/libxfs/xfs_trans_inode.c | 6 +- fs/xfs/xfs_iops.c | 6 +- fs/xfs/xfs_super.c | 2 +- include/linux/fs.h | 61 +++++--- include/trace/events/timestamp.h | 173 ++++++++++++++++++++++ mm/shmem.c | 2 +- 13 files changed, 639 insertions(+), 79 deletions(-) --- base-commit: 2e8c78ef85682671dae2ac3a5aa039b07be0fc0b change-id: 20240626-mgtime-5cd80b18d810 Best regards,