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 48695C54EBD for ; Wed, 4 Jan 2023 13:38:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239519AbjADNh6 (ORCPT ); Wed, 4 Jan 2023 08:37:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239801AbjADNhZ (ORCPT ); Wed, 4 Jan 2023 08:37:25 -0500 X-Greylist: delayed 135 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 04 Jan 2023 05:37:17 PST Received: from p3plsmtpa12-02.prod.phx3.secureserver.net (p3plsmtpa12-02.prod.phx3.secureserver.net [68.178.252.231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B6FBB11 for ; Wed, 4 Jan 2023 05:37:17 -0800 (PST) Received: from localhost ([82.17.115.212]) by :SMTPAUTH: with ESMTPA id D3v2pfNMzdnFID3v3pOI73; Wed, 04 Jan 2023 06:35:01 -0700 X-CMAE-Analysis: v=2.4 cv=OtSJiQzt c=1 sm=1 tr=0 ts=63b58085 a=9gipVNR6X1CoIeAWHwLoWw==:117 a=9gipVNR6X1CoIeAWHwLoWw==:17 a=IkcTkHD0fZMA:10 a=10cxsorouKqAV6tjQI0A:9 a=QEXdDO2ut3YA:10 X-SECURESERVER-ACCT: atomlin@atomlin.com Date: Wed, 4 Jan 2023 13:34:59 +0000 From: Aaron Tomlin To: Frederic Weisbecker Cc: Marcelo Tosatti , cl@linux.com, tglx@linutronix.de, mingo@kernel.org, peterz@infradead.org, pauld@redhat.com, neelx@redhat.com, oleksandr@natalenko.name, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v12 2/6] mm/vmstat: Use vmstat_dirty to track CPU-specific vmstat discrepancies Message-ID: <20230104133459.5yaflf3yicpmhbbh@ava.usersys.com> References: <20221227121137.102497574@redhat.com> <20221227121341.981235373@redhat.com> <20221230132132.GA186035@lothringen> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20221230132132.GA186035@lothringen> X-CMAE-Envelope: MS4xfFA/uiN5hbKR/L31JmptVVhPRsARrLU7WBDehIBzhMxSZcxbBRUHhVl5Q3RD9uMKRFoYIB6a9w+0oldFH4hNfryhz98qvH5hD2s7YKCfhbG/wW1toJr8 ibdeHnwgiZ5xuZQgFsoruKjde1wlQe7xGBXq6DG0OZd66zFZ0bR55hlRdhPobkaMNpc1zGsv2vJiI0hlQ6eL23baSaapoe+p/KwdsViua2WPV5o1CHBYSWpW EgXeY0oNbfEbjHzGmoTMH8dR0XegGWkrvGOLSR6gnB9DZLgudtEngQcLdeEaca8SXBPGKLNH1pBYj3BBAWREpABvBQHIv8VbCqnpOfKyfNRETKexXOXQfQ4J 5r/y+9bMe4iywjpm7R3vQ2Mg91dtGTlhnQUx6nIECbDikyein5POLuPVRmU47edKImUfpBlJOs9BjxUoJdplajJRHHZjuJ8T0W5yRsf4gXSnYwMFbYqLGgqQ XsuPxuDLkxEUoVvN Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 2022-12-30 14:21 +0100, Frederic Weisbecker wrote: > On Tue, Dec 27, 2022 at 09:11:39AM -0300, Marcelo Tosatti wrote: > > @@ -606,6 +608,7 @@ static inline void mod_zone_state(struct > > > > if (z) > > zone_page_state_add(z, zone, item); > > + vmstat_mark_dirty(); > > } > > > > void mod_zone_page_state(struct zone *zone, enum zone_stat_item item, > > @@ -674,6 +677,7 @@ static inline void mod_node_state(struct > > > > if (z) > > node_page_state_add(z, pgdat, item); > > + vmstat_mark_dirty(); > > Looking at this further, about the two above chunks, there is a risk to > mark the wrong CPU dirty because those functions are preemptible and rely > on this_cpu_cmpxchg() to deal with preemption. Hi Frederic, Agreed. Kind regards, -- Aaron Tomlin