From patchwork Mon Jul 1 10:26:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 13717781 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97A0AC30659 for ; Mon, 1 Jul 2024 10:27:14 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 062816B0096; Mon, 1 Jul 2024 06:27:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EB9426B0098; Mon, 1 Jul 2024 06:27:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C6F6D6B0099; Mon, 1 Jul 2024 06:27:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 9E44C6B0096 for ; Mon, 1 Jul 2024 06:27:13 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 3FE4CC1B34 for ; Mon, 1 Jul 2024 10:27:13 +0000 (UTC) X-FDA: 82290806346.05.619ADE5 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf28.hostedemail.com (Postfix) with ESMTP id 6F11FC0019 for ; Mon, 1 Jul 2024 10:27:11 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=fH62UWFL; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf28.hostedemail.com: domain of jlayton@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jlayton@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719829614; a=rsa-sha256; cv=none; b=iBDn0fnOUu6jiN4/L5psFd9Eyu6N4Cr9o2pbhMKDLg5I9xq4oOTPwVDgRqe44yFn7TdJGO Qmd7OyfcAY0B43DpumLTBd3rW+VG5LrDuSeSwD6KxLbEwjqbSKu6elLW7ZQRlatsVs3fny eFU6EyBSv2ISzGjACTqp2mEOKdsVCO0= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=fH62UWFL; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf28.hostedemail.com: domain of jlayton@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jlayton@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719829614; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=x09LagcIXSQFyjuTYLCcAzu/+JTLEhX/FTgIJyNoLak=; b=AXaHUeF9M3h4NwFA2CIzuHK3ULXFcMNUKl6QQmF0Y7DCr4KILxycdwe09eSfsy9RuWP+gD PGLDd8UkYAEkY/NtP8N7ZDkv9KzrnITXeK/M0Q0nw3w8M76vvfCyaIAgrVnyAqnj7a4YNS sU2FHEuUZNtZ4d9y4QvVqIT7D/sv+jc= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A214A6124D; Mon, 1 Jul 2024 10:27:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61429C4AF0F; Mon, 1 Jul 2024 10:27:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719829630; bh=ZBKByquYEdSc8HMPTmMqO17BDUigbAna6N8Jb8o7VIE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=fH62UWFLV1muAZCZ9Uqg8bup5NTWlC8DFd1KVhJmlGrmNURVzr8eb8sA0Ls90voPR BbWcdY9SGonGUlyLLohh8+/QHnD9ygByoLBqltTBBsxFJG8QpTGWgi+DTFDv40qK2k FoaAfg3P+swSTgSp56VoeYVv3XfaKaaOmfXxmuqvBBmKFtikx+s7Yd0In339RLRYtH 5DvYLSg6Z+QQFmoaTW5xjJjLvLIoqs0qwKH0u2qrUxflf/dYxqRXZjdcX5xrYSNoD1 6Bu6MS8IxZDMSEHAo90bvmQWpynDEH0t3qJ5M+xLfvP0rnFo0ZTsCBL4UM5tjESSK3 UbDe+sB/rUbqA== From: Jeff Layton Date: Mon, 01 Jul 2024 06:26:37 -0400 Subject: [PATCH v2 01/11] fs: turn inode ctime fields into a single ktime_t MIME-Version: 1.0 Message-Id: <20240701-mgtime-v2-1-19d412a940d9@kernel.org> References: <20240701-mgtime-v2-0-19d412a940d9@kernel.org> In-Reply-To: <20240701-mgtime-v2-0-19d412a940d9@kernel.org> 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=3344; i=jlayton@kernel.org; h=from:subject:message-id; bh=ZBKByquYEdSc8HMPTmMqO17BDUigbAna6N8Jb8o7VIE=; b=kA0DAAgBAA5oQRlWghUByyZiAGaChHij2CN1I/zkl//fedCXp9VjMU5Dtw3Kbn8GML+q0mPsf 4kCMwQAAQgAHRYhBEvA17JEcbKhhOr10wAOaEEZVoIVBQJmgoR4AAoJEAAOaEEZVoIVvDQQAMSY w7rzKxq0PvZZk5HYZj1Fd+MbtYtz2FqcFHuKdCL1wNI9qSIh5roycQHJdjwhp7tcgrSW076CBD8 tEJj4kkd46Nm7jKcMAy2Kv00LGcN29a5c5wnqj9AGRoTXpLf7C5tJBL31pKHj5ignjT4+59wlte o5ZuEo+Gm0ijd/j3es9lK7BIJMyMyFR3BDO5e7dg5rdhPOnt90Y8e9OjTkzc1rCeeVWeBCDDGcb 8LX8+xKrMExJonsClph8lXkxT5LrzJLbSIouBeBicEkm/xh5sbO0sV7fRuNPFZYm7CUyqJNnDJA /Olm4VSauOArxzOmuk+e6jPxboFFxHB7AuIWY1i8KcowJ1FQ4sIsGaqrJOiLnDyhrSeDIJAtOHf j2vthNwFYecOlAWDma4SRUfGpzuwd9Bxb1VZzZWUeL1PqOU+FIA81Wm88el2cdOV8SN4aH6ZcQF E1KZJsOwuDXw/FSgbgFifdijqi3jpaEfiyTiUfOSV/lh4GIYFpHc+1eHkgPOxYO2ty/NxZh35Z6 NJ/e1UPJRnNiFRMKHvPx16kwE4KAsvREDbAd3SRBhXkwBhw/aL1Sx7nYpQv9JENH+6dZeWBgTd9 INL5kJ3hGTS8vYlHAU/WeNNJlO44ASLpvswExclby6lH+tUv/o82oJAcjjfCPr/Y7ri/o+HSzLL 7WR8L X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 6F11FC0019 X-Stat-Signature: s4qkzm44t9111iuhzf7j535fbnykda4c X-Rspam-User: X-HE-Tag: 1719829631-666175 X-HE-Meta: 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 5SsV2mMh Da5B7BRuhWzV1EbWCEQWs7iNNT+NXY3nQFX7JDEPFJiZ2g+8KVI0Pk380Q6mB556n6xWMi0q09hn0DDtYBDYOETXE2rhOt4/VxevttCRAtCzBDAb2LMzz3/mJwFCNqcW3aBxI2cgH5/GANL/Y9pVOORjE9BYi3akQEASd2GYxRAwlBIF/fIIQ5GGr93sh8/ggh+rocAUxkYCSyzq8LrKJo3hxMKY8YwR4aMQz3aw8ySREqgZMVBJstNIH59HsqQ2eY3QoumviOFW2VbuEGcaqvO0JDIWtWAIE9NnQB8tWqj0Skhpo3dVmthQQrb4LWfW26FISEl7mH+mOji0wJ7HUcVC5Fxq/19AQ6HSFwVMCTbTTqEjcKH1V0g9PrKtjk3BWGwQs6DMjXyeJK/46G5yGpFNTV1bEEXoKEBZP X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: The ctime is not settable to arbitrary values. It always comes from the system clock, so we'll never stamp an inode with a value that can't be represented there. If we disregard people setting their system clock past the year 2262, there is no reason we can't replace the ctime fields with a ktime_t. Switch the ctime fields to a single ktime_t. Move the i_generation down above i_fsnotify_mask and then move the i_version into the resulting 8 byte hole. This shrinks struct inode by 8 bytes total, and should improve the cache footprint as the i_version and ctime are usually updated together. The one downside I can see to switching to a ktime_t is that if someone has a filesystem with files on it that has ctimes outside the ktime_t range (before ~1678 AD or after ~2262 AD), we won't be able to display them properly in stat() without some special treatment in the filesystem. The operating assumption here is that that is not a practical problem. Signed-off-by: Jeff Layton --- include/linux/fs.h | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 2fa06a4d197a..7110d6dc9aab 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -662,11 +662,10 @@ struct inode { loff_t i_size; time64_t i_atime_sec; time64_t i_mtime_sec; - time64_t i_ctime_sec; u32 i_atime_nsec; u32 i_mtime_nsec; - u32 i_ctime_nsec; - u32 i_generation; + ktime_t __i_ctime; + atomic64_t i_version; spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */ unsigned short i_bytes; u8 i_blkbits; @@ -701,7 +700,6 @@ struct inode { struct hlist_head i_dentry; struct rcu_head i_rcu; }; - atomic64_t i_version; atomic64_t i_sequence; /* see futex */ atomic_t i_count; atomic_t i_dio_count; @@ -724,6 +722,8 @@ struct inode { }; + u32 i_generation; + #ifdef CONFIG_FSNOTIFY __u32 i_fsnotify_mask; /* all events this inode cares about */ /* 32-bit hole reserved for expanding i_fsnotify_mask */ @@ -1608,29 +1608,25 @@ static inline struct timespec64 inode_set_mtime(struct inode *inode, return inode_set_mtime_to_ts(inode, ts); } -static inline time64_t inode_get_ctime_sec(const struct inode *inode) +static inline struct timespec64 inode_get_ctime(const struct inode *inode) { - return inode->i_ctime_sec; + return ktime_to_timespec64(inode->__i_ctime); } -static inline long inode_get_ctime_nsec(const struct inode *inode) +static inline time64_t inode_get_ctime_sec(const struct inode *inode) { - return inode->i_ctime_nsec; + return inode_get_ctime(inode).tv_sec; } -static inline struct timespec64 inode_get_ctime(const struct inode *inode) +static inline long inode_get_ctime_nsec(const struct inode *inode) { - struct timespec64 ts = { .tv_sec = inode_get_ctime_sec(inode), - .tv_nsec = inode_get_ctime_nsec(inode) }; - - return ts; + return inode_get_ctime(inode).tv_nsec; } static inline struct timespec64 inode_set_ctime_to_ts(struct inode *inode, struct timespec64 ts) { - inode->i_ctime_sec = ts.tv_sec; - inode->i_ctime_nsec = ts.tv_nsec; + inode->__i_ctime = ktime_set(ts.tv_sec, ts.tv_nsec); return ts; }