From mboxrd@z Thu Jan 1 00:00:00 1970 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 22689C61DA4 for ; Fri, 3 Feb 2023 06:52:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232007AbjBCGwP (ORCPT ); Fri, 3 Feb 2023 01:52:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45454 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232424AbjBCGva (ORCPT ); Fri, 3 Feb 2023 01:51:30 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CFF588D616 for ; Thu, 2 Feb 2023 22:51:20 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6F85FB8298A for ; Fri, 3 Feb 2023 06:51:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15634C433D2; Fri, 3 Feb 2023 06:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1675407078; bh=b+CCqjClbyGmKwsbO0QY6kCshl/8MLw+bHY69wL+NNQ=; h=Date:To:From:Subject:From; b=PPO+zuNHYBr4CD2STLMeqIwtYFe30KVY5h8nL2exaeLVq7o+ck3/JyEP5rrIqDFxy 1lPx5h1u+39I4FNEbKWWkXzbuMlRRbTlq1U+mcLl+L8edqeKKSz2YT3v104mH6kLE9 us7UuMlNHVOrRlfkS5FjVsv5QJiweg3+JCxto7h0= Date: Thu, 02 Feb 2023 22:51:17 -0800 To: mm-commits@vger.kernel.org, tytso@mit.edu, adilger.kernel@dilger.ca, ubizjak@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-nonmm-stable] fs-ext4-use-try_cmpxchg-in-ext4_update_bh_state.patch removed from -mm tree Message-Id: <20230203065118.15634C433D2@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: fs/ext4: use try_cmpxchg in ext4_update_bh_state has been removed from the -mm tree. Its filename was fs-ext4-use-try_cmpxchg-in-ext4_update_bh_state.patch This patch was dropped because it was merged into the mm-nonmm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Uros Bizjak Subject: fs/ext4: use try_cmpxchg in ext4_update_bh_state Date: Wed, 2 Nov 2022 08:11:47 +0100 Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in ext4_update_bh_state. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails. There is no need to re-read the value in the loop. No functional change intended. Link: https://lkml.kernel.org/r/20221102071147.6642-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak Cc: "Theodore Ts'o" Cc: Andreas Dilger Signed-off-by: Andrew Morton --- --- a/fs/ext4/inode.c~fs-ext4-use-try_cmpxchg-in-ext4_update_bh_state +++ a/fs/ext4/inode.c @@ -786,11 +786,10 @@ static void ext4_update_bh_state(struct * once we get rid of using bh as a container for mapping information * to pass to / from get_block functions, this can go away. */ + old_state = READ_ONCE(bh->b_state); do { - old_state = READ_ONCE(bh->b_state); new_state = (old_state & ~EXT4_MAP_FLAGS) | flags; - } while (unlikely( - cmpxchg(&bh->b_state, old_state, new_state) != old_state)); + } while (unlikely(!try_cmpxchg(&bh->b_state, &old_state, new_state))); } static int _ext4_get_block(struct inode *inode, sector_t iblock, _ Patches currently in -mm which might be from ubizjak@gmail.com are