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 06283C7EE24 for ; Tue, 30 May 2023 22:26:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233343AbjE3W02 (ORCPT ); Tue, 30 May 2023 18:26:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233516AbjE3W0Z (ORCPT ); Tue, 30 May 2023 18:26:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EE5FE5 for ; Tue, 30 May 2023 15:26:24 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id BA10A63446 for ; Tue, 30 May 2023 22:26:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FB5DC433D2; Tue, 30 May 2023 22:26:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1685485583; bh=sTyNaVqiGXhuOTLmuu9vENfaW7yhGSF/JZJie7JA/co=; h=Date:To:From:Subject:From; b=Vvxhec0anfZYV9dREEMNC8lB5ysGrb/L4cGnh60daePqWJVNzLiIzWRygjV/FGqRj AYE7TsRreVRBpc0yFonFUWOY07VXfWpTBbQOuLRUz884uwiInVAdZn829nh4VCugZL 9LazWc/DOjXakW+Z3zsOmT4LvtlbmzifhQnq+J0g= Date: Tue, 30 May 2023 15:26:22 -0700 To: mm-commits@vger.kernel.org, pmladek@suse.com, npiggin@gmail.com, mpe@ellerman.id.au, davem@davemloft.net, christophe.leroy@csgroup.eu, dianders@chromium.org, akpm@linux-foundation.org From: Andrew Morton Subject: + watchdog-buddy-dont-copy-the-cpumask-in-watchdog_next_cpu.patch added to mm-nonmm-unstable branch Message-Id: <20230530222623.1FB5DC433D2@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: watchdog/buddy: don't copy the cpumask in watchdog_next_cpu() has been added to the -mm mm-nonmm-unstable branch. Its filename is watchdog-buddy-dont-copy-the-cpumask-in-watchdog_next_cpu.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/watchdog-buddy-dont-copy-the-cpumask-in-watchdog_next_cpu.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Douglas Anderson Subject: watchdog/buddy: don't copy the cpumask in watchdog_next_cpu() Date: Fri, 26 May 2023 18:41:37 -0700 There's no reason to make a copy of the "watchdog_cpus" locally in watchdog_next_cpu(). Making a copy wouldn't make things any more race free and we're just reading the value so there's no need for a copy. Link: https://lkml.kernel.org/r/20230526184139.7.If466f9a2b50884cbf6a1d8ad05525a2c17069407@changeid Signed-off-by: Douglas Anderson Suggested-by: Petr Mladek Reviewed-by: Petr Mladek Cc: Christophe Leroy Cc: "David S. Miller" Cc: Michael Ellerman Cc: Nicholas Piggin Signed-off-by: Andrew Morton --- kernel/watchdog_buddy.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/kernel/watchdog_buddy.c~watchdog-buddy-dont-copy-the-cpumask-in-watchdog_next_cpu +++ a/kernel/watchdog_buddy.c @@ -10,12 +10,11 @@ static cpumask_t __read_mostly watchdog_ static unsigned int watchdog_next_cpu(unsigned int cpu) { - cpumask_t cpus = watchdog_cpus; unsigned int next_cpu; - next_cpu = cpumask_next(cpu, &cpus); + next_cpu = cpumask_next(cpu, &watchdog_cpus); if (next_cpu >= nr_cpu_ids) - next_cpu = cpumask_first(&cpus); + next_cpu = cpumask_first(&watchdog_cpus); if (next_cpu == cpu) return nr_cpu_ids; _ Patches currently in -mm which might be from dianders@chromium.org are migrate_pages-avoid-blocking-for-io-in-migrate_sync_light.patch watchdog-perf-define-dummy-watchdog_update_hrtimer_threshold-on-correct-config.patch watchdog-perf-more-properly-prevent-false-positives-with-turbo-modes.patch watchdog-hardlockup-add-comments-to-touch_nmi_watchdog.patch watchdog-perf-rename-watchdog_hldc-to-watchdog_perfc.patch watchdog-hardlockup-move-perf-hardlockup-checking-panic-to-common-watchdogc.patch watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch watchdog-hardlockup-add-a-cpu-param-to-watchdog_hardlockup_check.patch watchdog-hardlockup-move-perf-hardlockup-watchdog-petting-to-watchdogc.patch watchdog-hardlockup-rename-some-nmi-watchdog-constants-function.patch watchdog-hardlockup-have-the-perf-hardlockup-use-__weak-functions-more-cleanly.patch watchdog-hardlockup-detect-hard-lockups-using-secondary-buddy-cpus.patch watchdog-perf-add-a-weak-function-for-an-arch-to-detect-if-perf-can-use-nmis.patch arm64-enable-perf-events-based-hard-lockup-detector.patch arm64-enable-perf-events-based-hard-lockup-detector-fix.patch watchdog-hardlockup-keep-kernelnmi_watchdog-sysctl-as-0444-if-probe-fails.patch watchdog-hardlockup-have_nmi_watchdog-must-implement-watchdog_hardlockup_probe.patch watchdog-hardlockup-dont-use-raw_cpu_ptr-in-watchdog_hardlockup_kick.patch watchdog-hardlockup-in-watchdog_hardlockup_check-use-cpumask_copy.patch watchdog-hardlockup-remove-softlockup-comment-in-touch_nmi_watchdog.patch watchdog-buddy-cleanup-how-watchdog_buddy_check_hardlockup-is-called.patch watchdog-buddy-dont-copy-the-cpumask-in-watchdog_next_cpu.patch watchdog-buddy-simplify-the-dependency-for-hardlockup_detector_prefer_buddy.patch watchdog-hardlockup-move-smp-barriers-from-common-code-to-buddy-code.patch watchdog-hardlockup-rename-have_hardlockup_detector_non_arch-to-_perf_or_buddy.patch