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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5CA9CFB5EBC for ; Tue, 17 Mar 2026 04:37:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BFEC06B0005; Tue, 17 Mar 2026 00:37:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BD6806B0088; Tue, 17 Mar 2026 00:37:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B14236B0089; Tue, 17 Mar 2026 00:37:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id A18146B0005 for ; Tue, 17 Mar 2026 00:37:17 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 5E48013AF36 for ; Tue, 17 Mar 2026 04:37:17 +0000 (UTC) X-FDA: 84554295714.02.3893DF4 Received: from out-177.mta0.migadu.com (out-177.mta0.migadu.com [91.218.175.177]) by imf01.hostedemail.com (Postfix) with ESMTP id 516944000C for ; Tue, 17 Mar 2026 04:37:15 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="fYW/2Z+H"; spf=pass (imf01.hostedemail.com: domain of jp.kobryn@linux.dev designates 91.218.175.177 as permitted sender) smtp.mailfrom=jp.kobryn@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1773722235; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=g/D/uyf3nn8bxGRwMVEfXcttdOuJQ2DTCrN1S57yUG8=; b=bQg5Gy8bFs9EuXKNiDQ/JiUwNZ8wlnjQ8mh6zM1h8aMHNCjQ8qFKC72ihAlO3GNt568YKl Q+7G9Uj9I0kyEmEus819LbXeEP+4wNLgDhQoQiG7VeA/7xwV/LBK8UpyLAVMBIoZuQABc9 DgdoKD5I+rY3lOgzm2my4yns6idAPpw= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1773722235; a=rsa-sha256; cv=none; b=IcKZJVFHKGFNjl0H8a8XXFQ0IPHUYhobETAWFzjf2ST1SCZGXzKOf1Sgrk65wmvFGwAIma NrNBscA4y39VXrzruM+cRjqDQB42pUGUI/WJ45XLeki1GrMHi0wt5gAAm9e0E2NLnzCPzC n9O7BAmbfNPOW22wkX6kBhkYfKSQv2I= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="fYW/2Z+H"; spf=pass (imf01.hostedemail.com: domain of jp.kobryn@linux.dev designates 91.218.175.177 as permitted sender) smtp.mailfrom=jp.kobryn@linux.dev; dmarc=pass (policy=none) header.from=linux.dev Message-ID: <0d66401f-9874-4047-971b-632723b0b7ee@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1773722232; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=g/D/uyf3nn8bxGRwMVEfXcttdOuJQ2DTCrN1S57yUG8=; b=fYW/2Z+H7GDqviCHCJxlMlopFyd0rVRST+Kt+qnMmSRDH0/2HSkqYnt2zM4572KfZ1IoMF QdgnYxrOKNf7viUh8MhHQAFvHJN7K/tJkMImaj7zfLcg4xzDV79pXlx4AMJIuYxrBKmTmc 5yfsO6dct2hccDcLaUMMZOKdVvIkn3k= Date: Mon, 16 Mar 2026 21:37:01 -0700 MIME-Version: 1.0 Subject: Re: [PATCH v2] mm/mempolicy: track page allocations per mempolicy To: "Huang, Ying" Cc: "Vlastimil Babka (SUSE)" , linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@suse.com, apopple@nvidia.com, axelrasmussen@google.com, byungchul@sk.com, cgroups@vger.kernel.org, david@kernel.org, eperezma@redhat.com, gourry@gourry.net, jasowang@redhat.com, hannes@cmpxchg.org, joshua.hahnjy@gmail.com, Liam.Howlett@oracle.com, linux-kernel@vger.kernel.org, lorenzo.stoakes@oracle.com, matthew.brost@intel.com, mst@redhat.com, rppt@kernel.org, muchun.song@linux.dev, zhengqi.arch@bytedance.com, rakie.kim@sk.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, surenb@google.com, virtualization@lists.linux.dev, weixugc@google.com, xuanzhuo@linux.alibaba.com, yuanchu@google.com, ziy@nvidia.com, kernel-team@meta.com References: <20260307045520.247998-1-jp.kobryn@linux.dev> <3a42463b-9ddd-4d64-b64c-6c2e6e4fc75d@kernel.org> <343bbd5b-67a0-46c4-8ec4-69158bf26b3f@linux.dev> <874imkpba1.fsf@DESKTOP-5N7EMDA> <60f71f4c-71d9-4751-8c6b-10179b98bef0@kernel.org> <87sea0o55p.fsf@DESKTOP-5N7EMDA> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: "JP Kobryn (Meta)" In-Reply-To: <87sea0o55p.fsf@DESKTOP-5N7EMDA> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 516944000C X-Stat-Signature: qxgaa8pmt4rbb1fhnk79djchq81c73ss X-Rspam-User: X-HE-Tag: 1773722235-24095 X-HE-Meta: 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 vTB0Uu5X YkE7AXzibz+yoCK+Cilx2AsrVfEI5gTvUP+sTQk+q53E1OWtsFZODAQU2JwmTXwk2N/b9UKDzJfSvnBF7S0PsGMRof3/9SLzcIZsPNUkcl0KnOnEpBZPkvst324bfFwPK/XYK5wsHglBsfioVViKTrGPds13GrueSuk9ZI00+PiQjRy9Hv7PLzsQbDUsm54VPyST9aBtIKecxBU+Gc/9XBsjHuYt3b2ROWMOrNdoW/NDOzcrBzY1OGU5RZwlnGhIkSnZhWIg81g4B5bUd2J8rPFuOHXhZThQUtpajWHaZZaogyN3B15zlZsEPoErBq1SHrewO Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/15/26 7:54 PM, Huang, Ying wrote: > "JP Kobryn (Meta)" writes: > >> On 3/13/26 12:34 AM, Vlastimil Babka (SUSE) wrote: >>> On 3/13/26 07:14, JP Kobryn (Meta) wrote: >>>> On 3/12/26 10:07 PM, Huang, Ying wrote: >>>>> "JP Kobryn (Meta)" writes: >>>>> >>>>>> On 3/12/26 6:40 AM, Vlastimil Babka (SUSE) wrote: >>>>>> >>>>>> How about I change from per-policy hit/miss/foreign triplets to a single >>>>>> aggregated policy triplet (i.e. just 3 new counters which account for >>>>>> all policies)? They would follow the same hit/miss/foreign semantics >>>>>> already proposed (visible in quoted text above). This would still >>>>>> provide the otherwise missing signal of whether policy-driven >>>>>> allocations to a node are intentional or fallback. >>>>>> >>>>>> Note that I am also planning on moving the stats off of the memcg so the >>>>>> 3 new counters will be global per-node in response to similar feedback. >>>>> >>>>> Emm, what's the difference between these newly added counters and the >>>>> existing numa_hit/miss/foreign counters? >>>> >>>> The existing counters don't account for node masks in the policies that >>>> make use of them. An allocation can land on a node in the mask and still >>>> be considered a miss because it wasn't the preferred node. >>> That sounds like we could just a new counter e.g. numa_hit_preferred >>> and >>> adjust definitions accordingly? Or some other variant that fills the gap? >> >> It's an interesting thought. Looking into these existing counters more, >> the in-kernel direct node allocations, which don't fall under any >> mempolicy, are also included in these stats. One good example might be >> include/linux/skbuff.h, where __dev_alloc_pages() calls >> alloc_pages_node_noprof(NUMA_NO_NODE, ...) which eventually reaches >> zone_statistics() and increments the stats. > > IIUC, the default memory policy is used here, that is, MPOL_LOCAL. I'm not seeing that. zone_statistics() is eventually reached. alloc_pages_mpol() is not.