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 81194C61DA4 for ; Mon, 13 Mar 2023 18:08:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229531AbjCMSH6 (ORCPT ); Mon, 13 Mar 2023 14:07:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230223AbjCMSHt (ORCPT ); Mon, 13 Mar 2023 14:07:49 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E1DE769FA for ; Mon, 13 Mar 2023 11:07:44 -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 ams.source.kernel.org (Postfix) with ESMTPS id 35AC3B811C5 for ; Mon, 13 Mar 2023 18:07:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA3B6C4339C; Mon, 13 Mar 2023 18:07:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1678730861; bh=BQ5tSyAcm3KfHpTJafgisYDc0z6R3TIk8G7TTyKZu+Y=; h=Date:To:From:Subject:From; b=VOtDZlFhiyoMx11RYjyEvtEfzaaV6XgQJGpqKUs/rCr4pTbcGLbi/lWopGZqmtht3 +QgsjVqigfjLie0EzyiieCifWuygWu9UJ2O6t31cK6/ixuOY4j4Vm2qr75TVFDYAYl HVSTD814cbI+heuvIT9+r7gtMB55bvhg5XLkya64= Date: Mon, 13 Mar 2023 11:07:41 -0700 To: mm-commits@vger.kernel.org, willy@infradead.org, vbabka@suse.cz, thomas.hellstrom@linux.intel.com, peterx@redhat.com, mhocko@suse.com, lstoakes@gmail.com, linux@armlinux.org.uk, kirill.shutemov@linux.intel.com, jgg@ziepe.ca, hca@linux.ibm.com, frederic@kernel.org, dan.j.williams@intel.com, cl@linux.com, christian.koenig@amd.com, chenhuacai@kernel.org, atomlin@atomlin.com, mtosatti@redhat.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-vmstat-use-xchg-in-cpu_vm_stats_fold.patch added to mm-unstable branch Message-Id: <20230313180741.BA3B6C4339C@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: mm/vmstat: use xchg in cpu_vm_stats_fold has been added to the -mm mm-unstable branch. Its filename is mm-vmstat-use-xchg-in-cpu_vm_stats_fold.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmstat-use-xchg-in-cpu_vm_stats_fold.patch This patch will later appear in the mm-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: Marcelo Tosatti Subject: mm/vmstat: use xchg in cpu_vm_stats_fold Date: Mon, 13 Mar 2023 13:25:16 -0300 In preparation to switch vmstat shepherd to flush per-CPU counters remotely, use xchg instead of a pair of read/write instructions. Link: https://lkml.kernel.org/r/20230313162634.482796394@redhat.com Signed-off-by: Marcelo Tosatti Cc: Aaron Tomlin Cc: Christian König Cc: Christoph Lameter Cc: Dan Williams Cc: Frederic Weisbecker Cc: Heiko Carstens Cc: Huacai Chen Cc: Jason Gunthorpe Cc: Kirill A. Shutemov Cc: Lorenzo Stoakes Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Peter Xu Cc: "Russell King (Oracle)" Cc: Thomas Hellström Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- --- a/mm/vmstat.c~mm-vmstat-use-xchg-in-cpu_vm_stats_fold +++ a/mm/vmstat.c @@ -924,7 +924,7 @@ static int refresh_cpu_vm_stats(bool do_ } /* - * Fold the data for an offline cpu into the global array. + * Fold the data for a cpu into the global array. * There cannot be any access by the offline cpu and therefore * synchronization is simplified. */ @@ -945,8 +945,7 @@ void cpu_vm_stats_fold(int cpu) if (pzstats->vm_stat_diff[i]) { int v; - v = pzstats->vm_stat_diff[i]; - pzstats->vm_stat_diff[i] = 0; + v = xchg(&pzstats->vm_stat_diff[i], 0); atomic_long_add(v, &zone->vm_stat[i]); global_zone_diff[i] += v; } @@ -956,8 +955,7 @@ void cpu_vm_stats_fold(int cpu) if (pzstats->vm_numa_event[i]) { unsigned long v; - v = pzstats->vm_numa_event[i]; - pzstats->vm_numa_event[i] = 0; + v = xchg(&pzstats->vm_numa_event[i], 0); zone_numa_event_add(v, zone, i); } } @@ -973,8 +971,7 @@ void cpu_vm_stats_fold(int cpu) if (p->vm_node_stat_diff[i]) { int v; - v = p->vm_node_stat_diff[i]; - p->vm_node_stat_diff[i] = 0; + v = xchg(&p->vm_node_stat_diff[i], 0); atomic_long_add(v, &pgdat->vm_stat[i]); global_node_diff[i] += v; } _ Patches currently in -mm which might be from mtosatti@redhat.com are this_cpu_cmpxchg-arm64-switch-this_cpu_cmpxchg-to-locked-add-_local-function.patch this_cpu_cmpxchg-loongarch-switch-this_cpu_cmpxchg-to-locked-add-_local-function.patch this_cpu_cmpxchg-s390-switch-this_cpu_cmpxchg-to-locked-add-_local-function.patch this_cpu_cmpxchg-x86-switch-this_cpu_cmpxchg-to-locked-add-_local-function.patch add-this_cpu_cmpxchg_local-and-asm-generic-definitions.patch convert-this_cpu_cmpxchg-users-to-this_cpu_cmpxchg_local.patch mm-vmstat-switch-counter-modification-to-cmpxchg.patch vmstat-switch-per-cpu-vmstat-counters-to-32-bits.patch mm-vmstat-use-xchg-in-cpu_vm_stats_fold.patch mm-vmstat-switch-vmstat-shepherd-to-flush-per-cpu-counters-remotely.patch mm-vmstat-refresh-stats-remotely-instead-of-via-work-item.patch vmstat-add-pcp-remote-node-draining-via-cpu_vm_stats_fold.patch