From patchwork Wed Oct 18 17:41:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeffrey Layton X-Patchwork-Id: 13427591 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B40ECDB486 for ; Wed, 18 Oct 2023 17:41:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231414AbjJRRlp (ORCPT ); Wed, 18 Oct 2023 13:41:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39280 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231215AbjJRRlh (ORCPT ); Wed, 18 Oct 2023 13:41:37 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EDED11C; Wed, 18 Oct 2023 10:41:34 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F0865C433CD; Wed, 18 Oct 2023 17:41:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1697650894; bh=jWmZ1Ravl5cu/wOo4Bog6k1d+CwyPST2G6rAUV4ZYAc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=vHqr3PeTFpDRNPF3idVxxCdnb1iVi0NE8DkKoUZrVcZEfyflEgmWCoz3c30QBIYgV QHUjC6yzrdbgCryMrV/z8AraieOhCmp5ydSy1Jlqy/frfz3I7YSKlgI5kDCw9W9L0G 6wdcPzpynxo6jrP6c7EPrU4xUvOBBF8acqKT80+bwKIiWoG+0FKGZn2rspmzYEp5Uw yczqNkmwK3PiefZQP5RsLlEHZJRaSQCGu1OYDHgU58+Yl+kixzJq6GJmgUYJk5WB9q jGypQFbK++CbII2WD5VXoDWHRSnbQ9wKs9T6uoUfg0c1QygVUa4DSDyJFGF5QUtR0X akQ1ufOzxnSZQ== From: Jeff Layton Date: Wed, 18 Oct 2023 13:41:08 -0400 Subject: [PATCH RFC 1/9] fs: switch timespec64 fields in inode to discrete integers MIME-Version: 1.0 Message-Id: <20231018-mgtime-v1-1-4a7a97b1f482@kernel.org> References: <20231018-mgtime-v1-0-4a7a97b1f482@kernel.org> In-Reply-To: <20231018-mgtime-v1-0-4a7a97b1f482@kernel.org> To: Linus Torvalds , Alexander Viro , Christian Brauner , John Stultz , Thomas Gleixner , Stephen Boyd , Chandan Babu R , "Darrick J. Wong" , Dave Chinner , Theodore Ts'o , Andreas Dilger , Chris Mason , Josef Bacik , David Sterba , Hugh Dickins , Andrew Morton , Amir Goldstein , Jan Kara , David Howells Cc: linux-fsdevel@vger.kernel.org, linux-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 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=4674; i=jlayton@kernel.org; h=from:subject:message-id; bh=jWmZ1Ravl5cu/wOo4Bog6k1d+CwyPST2G6rAUV4ZYAc=; b=owEBbQKS/ZANAwAIAQAOaEEZVoIVAcsmYgBlMBjIMZMk9hA0a0rbXtgzOBS8+JUCWebR2P/8J wgnb+onjoOJAjMEAAEIAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCZTAYyAAKCRAADmhBGVaC FRN4D/4hg/46V/lM9F5UuttDEfFBixG4KR0EymQEurGFApb4lySZ+KxbxVkqAm7IyL+FGAaylWc HWdk3vSQOpB0wg/2wS4ymKQcXH85SVmR/9XEb7cwkGmGji5l1IRuyksbprbUJUoYrd74o3VwZ2J FGfFODjJ1z2g8QOi+FPBhSrHSMPe6a+6t1RhTll6jSfUaLC5mT72UQKVTqezrCk3c7BrDg7wF8W P3sKppsD3IboBFnqLbTs+9FMukgmOdVC5ot278zCccIfSVSTWJov4PuYGZGg2sxnKJHL00sXNzC UpTPwBA06FEZnVVSubHR+v91WVQ9P8C7VgWnpAkNm0CuuoNGtBmtvA7dEM95ePdvysiYdTNgfbL lw9ll9YwoDxfKsgg8rC6dm6qHAEDZ4d2yBpi2ytPeV6cosMnf7ABN6v1L7saN4C9DAj43QdvZ0L NI9Sf0xSeBKtgKlsAkaKw1vFv9SxFWOvRLr06pyTa7aogQymJeKR714W1uy52Hb7lXCTSQGiDqt LBOBs244/a4JkQg0YfaivbgWS4haeHjH/Tc/YCT7wc6YGa+dUSQIviYyiczEXqT1Xvim3WEL+vK QXaNIVewLajwOQrViIMfh0wl3NievUibTIxrqaKsoZH9/zvSBivCwxyjO+SU5bOzzJvjm6OM1Zz MO1qldTLt22SnAw== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org This shaves 8 bytes off struct inode with a garden-variety Fedora Kconfig, but it moves the i_lock into the previous cacheline, away from the fields it protects. To remedy that, move the i_generation just after the nanosecond fields, which moves the 4 byte hole down next to i_fsnotify_mask. Suggested-by: Linus Torvalds Suggested-by: Amir Goldstein Signed-off-by: Jeff Layton --- include/linux/fs.h | 56 +++++++++++++++++++++++++++++++----------------------- 1 file changed, 32 insertions(+), 24 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index cc29518517f7..78786c1c32fd 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -671,9 +671,13 @@ struct inode { }; dev_t i_rdev; loff_t i_size; - struct timespec64 __i_atime; - struct timespec64 __i_mtime; - struct timespec64 __i_ctime; /* use inode_*_ctime accessors! */ + 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; spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */ unsigned short i_bytes; u8 i_blkbits; @@ -730,10 +734,10 @@ struct inode { unsigned i_dir_seq; }; - __u32 i_generation; #ifdef CONFIG_FSNOTIFY __u32 i_fsnotify_mask; /* all events this inode cares about */ + /* 32bit hole reserved for expanding i_fsnotify_mask to 64bit */ struct fsnotify_mark_connector __rcu *i_fsnotify_marks; #endif @@ -1513,23 +1517,27 @@ struct timespec64 inode_set_ctime_current(struct inode *inode); static inline time64_t inode_get_atime_sec(const struct inode *inode) { - return inode->__i_atime.tv_sec; + return inode->i_atime_sec; } static inline long inode_get_atime_nsec(const struct inode *inode) { - return inode->__i_atime.tv_nsec; + return inode->i_atime_nsec; } static inline struct timespec64 inode_get_atime(const struct inode *inode) { - return inode->__i_atime; + struct timespec64 ts = { .tv_sec = inode_get_atime_sec(inode), + .tv_nsec = inode_get_atime_nsec(inode) }; + + return ts; } static inline struct timespec64 inode_set_atime_to_ts(struct inode *inode, struct timespec64 ts) { - inode->__i_atime = ts; + inode->i_atime_sec = ts.tv_sec; + inode->i_atime_nsec = ts.tv_nsec; return ts; } @@ -1538,28 +1546,32 @@ static inline struct timespec64 inode_set_atime(struct inode *inode, { struct timespec64 ts = { .tv_sec = sec, .tv_nsec = nsec }; + return inode_set_atime_to_ts(inode, ts); } static inline time64_t inode_get_mtime_sec(const struct inode *inode) { - return inode->__i_mtime.tv_sec; + return inode->i_mtime_sec; } static inline long inode_get_mtime_nsec(const struct inode *inode) { - return inode->__i_mtime.tv_nsec; + return inode->i_mtime_nsec; } static inline struct timespec64 inode_get_mtime(const struct inode *inode) { - return inode->__i_mtime; + struct timespec64 ts = { .tv_sec = inode_get_mtime_sec(inode), + .tv_nsec = inode_get_mtime_nsec(inode) }; + return ts; } static inline struct timespec64 inode_set_mtime_to_ts(struct inode *inode, struct timespec64 ts) { - inode->__i_mtime = ts; + inode->i_mtime_sec = ts.tv_sec; + inode->i_mtime_nsec = ts.tv_nsec; return ts; } @@ -1573,34 +1585,30 @@ static inline struct timespec64 inode_set_mtime(struct inode *inode, static inline time64_t inode_get_ctime_sec(const struct inode *inode) { - return inode->__i_ctime.tv_sec; + return inode->i_ctime_sec; } static inline long inode_get_ctime_nsec(const struct inode *inode) { - return inode->__i_ctime.tv_nsec; + return inode->i_ctime_nsec; } static inline struct timespec64 inode_get_ctime(const struct inode *inode) { - return inode->__i_ctime; + struct timespec64 ts = { .tv_sec = inode_get_ctime_sec(inode), + .tv_nsec = inode_get_ctime_nsec(inode) }; + + return ts; } static inline struct timespec64 inode_set_ctime_to_ts(struct inode *inode, struct timespec64 ts) { - inode->__i_ctime = ts; + inode->i_ctime_sec = ts.tv_sec; + inode->i_ctime_nsec = ts.tv_nsec; return ts; } -/** - * inode_set_ctime - set the ctime in the inode - * @inode: inode in which to set the ctime - * @sec: tv_sec value to set - * @nsec: tv_nsec value to set - * - * Set the ctime in @inode to { @sec, @nsec } - */ static inline struct timespec64 inode_set_ctime(struct inode *inode, time64_t sec, long nsec) {