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 34FADC43458 for ; Tue, 30 Jun 2026 07:29:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E70CB6B00AB; Tue, 30 Jun 2026 03:28:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E48E96B00AC; Tue, 30 Jun 2026 03:28:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D36676B00AD; Tue, 30 Jun 2026 03:28:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id A7D916B00AB for ; Tue, 30 Jun 2026 03:28:59 -0400 (EDT) Received: from smtpin04.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 23FFF1C6D80 for ; Tue, 30 Jun 2026 07:28:59 +0000 (UTC) X-FDA: 84935752398.04.53134EB Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf28.hostedemail.com (Postfix) with ESMTP id 6A1FBC0004 for ; Tue, 30 Jun 2026 07:28:57 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=ZFn1H9jl; spf=pass (imf28.hostedemail.com: domain of vbabka@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=vbabka@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1782804537; b=idc5/+rFll1QDr9Kjyi8pzxnXzB6cs9p+oNF/J9Z7Qyxr6+Kbb60OXg/JluHdoHcv4zC0X 5mDHsz1D552JJluzMFOKU64GJnpLtckk1jVdbRXm9qumv4rOYjfcFm2nJWtzLkZjNx0ZEj 6mIXxYpfEEz7rGDhheofrXOVyj/Cu5I= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1782804537; 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=e98YwUYuEo+jW47qdB3B72qgzQCPcBwfH7OsRH/ROPs=; b=fKg1RFnxqJ6OD+7dxOjMcp5Ip28ZDKMBA3Lf+aRCrVkhA5iqjD9FQqNLuhwtoXf7Gw83eA cWR0WiGUYuDOyE7ZNnaEzq3z+X+q1Rpg5CBRjZJcWJ7iGXc8Y7tZbIixFI09CXj9wJE/x7 01tVEHWohsUKcH2qXEDaosBiDF+Xnts= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=ZFn1H9jl; spf=pass (imf28.hostedemail.com: domain of vbabka@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=vbabka@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id D5F02600C3; Tue, 30 Jun 2026 07:28:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B7FD1F00A3A; Tue, 30 Jun 2026 07:28:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782804536; bh=e98YwUYuEo+jW47qdB3B72qgzQCPcBwfH7OsRH/ROPs=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=ZFn1H9jlfNmlH1zT6vtcHSnaiSbi+w7BvliNM5mVDFp+wwRol6gWi8l9XJFmyVO4V ZC1OzZrcylNAncXXABpRL0ALxO4K0qJwrvq4T8JaZ0mF0FJDHf/t1F0M0aTTptdnGV DekqlyscJV/ndvE/m1VWbF5ajxosTl6fQCgEMhkhHvYEtCbwwGiPwS22eCKS3vFCNn ds5NL/4mLjXeCEHrOH8GvdmXJ7DOAxUDaCZRo4Otx6TJe/MQV3VzXtdtDd58ZYvjV7 peUS7KnRBrPkttuQkrZbMkvM+YX+uFCx6hhhtWH4ZAt9u8l6FTINtva91gsMByKy6v YiKx4MywKrGtw== Message-ID: Date: Tue, 30 Jun 2026 09:28:50 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 2/7] mm/page_owner: add MR_NEVER to enum migrate_reason and use it for last_migrate_reason Content-Language: en-US To: Ye Liu , Andrew Morton , David Hildenbrand , Steven Rostedt , Masami Hiramatsu Cc: Zi Yan , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Mathieu Desnoyers , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <20260630015331.147174-1-ye.liu@linux.dev> <20260630015331.147174-3-ye.liu@linux.dev> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSNWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBrZXJuZWwub3JnPsLBsAQTAQoAWhYhBKlA1DSZLC6OmRA9UCJPp+fM gqZkBQJqFFy6GxSAAAAAAAQADm1hbnUyLDIuNSsxLjEyLDIsMgIbAwUJGtCBUAULCQgHAwUV CgkICwUWAgMBAAIeBQIXgAAKCRAiT6fnzIKmZJIUEADFx/tREzUImHrEwVHeSvDFmA7tJysI UVrlvrM09E7GIuzphzv7jYmo8n3ANpCczLEVr4G0syYQdTigaZgv3+FQDIIzhKih1IHhu1Ei XHlywNWKnQxxQEUNi5Mwx43wQz5XVw9F1A7gtKBKNtfogO511hAbrzagrYajyQacEJ/+sfhZ 9Da8ltHIXD8pcYaHUfQgEusCgmEd9+KrUwrTbckFKmYq5chuE6yJ4J0EmWknL096jIE6CnzF FRslQ3B1UKDjxVsm1ZHfir5NeWszLkTvGFsddFaWTgh8UycESG6VQzKXjjewXu2pG7YQYRpj QKm1W5X2TkwWkXRBZTmfmbhxIUMh3+zf5wQ463rSmDN/8v81tdqBtAW6rH/kzg1GvkaTHXn0 507yEHFzBksk2viAuIxxr7km8+/KARYLIdGtx30EG8cKzAUZOK6WqxtNCsXUJNrVE8CWrCaD icoNu7Fs1c5hmPHdSTnU48ce67449DdnO4neLSNhRiGlMHJgfJUmgrxu/hcYeOZ3haWmEQ2w uW1Mh01OHi8QZHCEyAbABrPs9GUgccc/4eYXX9hIgxfSkYzn8f+8NuIFPWl/0uTvjgqU29FQ SbzOLxHq9439Ox40G5mS5eZXRGxITYR+6TXvRGI6P/264jvflnr/pDGUttaikU+0W+1uxgKH cmYbEc7ATQRbGTU1AQgAn0H6UrFiWcovkh6EXVcl+SeqyO6JHOPm+e9Wu0Vw+VIUvXZVUVVQ La1PQDUi6j00ChlcR66g9/V0sPIcSutacPKfdKYOBvzd4rlhL8rfrdEsQw5ApZxrA8kYZVMh FmBRKAa6wos25moTlMKpCWzTH84+WO5+ziCTsTUZASAToz3RdunTD+vQcHj0GqNTPAHK63sf bAB2I0BslZkXkY1RLb/YhuA6E7JyEd2pilZOrIuBGl/5q2qSakgnAVFWFBR/DO27JuAksYnq +aH8vI0xGvwn75KqSk4UzAkDzWSmO4ZHuahKtQgZNsMYV+PGayRBX9b9zbldzopoLBdqHc4n jQARAQABwsF8BBgBCgAmAhsMFiEEqUDUNJksLo6ZED1QIk+n58yCpmQFAmfIHFQFCRYU6J8A CgkQIk+n58yCpmS2PA//bqN1LfcotmArgElsa+0EGZSQlYgK48pm8WAeTXTngudP9IJ4SuKY HR5RNjHcBeqN+Me0zxRqYzRb8nGanHEkDyf4Im8DQM8d6vbyU+FcPmG4skud4kgS1zMHnlVd SXfSIwKC/hKgdHG8aBV7545Lz9X6Iohea+94wneD0aw/hqF+QWewGZhWJriWAZtvEkzNjQOi 4U9F/trLten/x7bpphDSnDMKJtITbtzATT1Dq7o7VpIUK1nCTQALMuMjKCdi8OdU/+V+R3O4 0PXWvX8qrvqYapVbZ+9KqT74FsuB0Ya9uXwgBF2Q6cRuETZk5vqaqKxzqoQZCO8AOz/58j6O 2RHNy/mZEN+7tJ5Tsq42zVJ4jxsT8b9YplavCMsnBgDeRWhcbYhCyttoL7nYISyWg4kQYZ/P wIV3OuNv2f8iKYsxNsRuClOAF82+gvqOy1/1pprFjy8uo2pkoOrb63aOP3vO5VHnRKgra6dq NcaZ+c6J4H+nEJGi2SkHAUJz5oBzuThvPudLvPA/SK8sKoM01IRxSihev/S/5WLazXB1PGem OCbvzC1IjWJJraxiDJ5IygokapUa2RP7+WBR22skQ3SSl6G107QgWKSyTOGWEaRmV53vxQLV jXuCmzSSasTL60zq5yGrT4/DYQVSNEUiUbG4pYekxJujNeEDkUlky0Y= In-Reply-To: <20260630015331.147174-3-ye.liu@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: cstfpgdye11zbknr3bzc61oben7gpc8c X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 6A1FBC0004 X-HE-Tag: 1782804537-213870 X-HE-Meta: U2FsdGVkX1/qA1fKceanyO6mgQxy0GUe98/rp4zVcDDZkwLCkKCc3Nd8MUhkftpmrrCsTjBCZpJqSrlBXda0a+G+g30vJ2Hrno8PpMnDH/NpdCn50+OCYb0axOLWn0yhlkT1ITvung8ohBQjQIrVMhDKuAD8i2YuEBgOVVz9/xlitPGyMkP/q8yhrdBSf536JHZ4K1e46YZxRH23SLm7IAJ9GOCNrvolcCqf4tOQZkE8ZusHJ+1fFAs8O69wSJKkLNwuoZg6Pf1dFILgosugiPmqzKLHvsQ9Qw8+wyKZAeh9XejP1CU7k6GwqKtjDLMH1YsSY6Qm8ddB6MmIbWbRH5DSR4WoJ/dHwpj5moCqz0rLRfoB8ee8SpZk4J7ZEqqlbD3irtLi0cCvTHFDiI55FE0sqb/jiYGSLbaTVurqe77lwXuSIjR8NMiDQWtXerhYZkcs59o0AgY7CAF30Qdb3Lfk8lZnUjpNte7VRIu01G6ww3uyb06aICYHcEg/V4ORU6mGweSAv4/2H86BUairuI7D0eYtk+hMR/O58uphijlv/kRAVu6YaocbCBIqXkQtnJrVFlEjeOy8v6pOQ83gjXEDEbd02r0zf6te7HBq35jLWMUnuKhMcA5UTHlqpYKRfDZXpE/FLK2VWTN2clNHSP5LYFRqMghbDQw0cbnwgFusOSIaDF7y/zsXf27WtPjC5SIhSIq2vB7O57bcse5UDfGKnHLJzuB2ZrHipSJXyVtjX2t54DdYhewuNoFIn0qzhZ7yrpd/W+NocUAa1n5nQSb7fv70L6ZCmZN5glnd7WpG+qt4YQAfd0agfhYs3PmoiqHWCUkde3VAq3DoRgOk0kNmIpb9qvto9t2ZJpXP8mby2N+FOwJQR5wAaKZqWSM5bZENLnfApLIyTA+PwTHqoDu2brc2LFWYy0Szb+ToYKPcp2FD1H2K6ljuNzINvN6RyPvQCNkjEePJrIkCAnW YTh4rFWm vtvZlavgvMcM6QbgqiMCuDj7Xgm7dkmIeusePwe9W0ayEUGCo17iL2eiooHjQSs6XnGSY2JZUaLy690F9QSWdoJCQFOrSbYeXC458ya42C1pKapc2c6Eu4GDoNd5v+mOMOcEsW2cDStqcE4nvcvrp44ivtmzAgimpKjQ2HvPmpt6uNFiqkh0V4+XbKH2XQnNa1r2h0TKynU72TYFx4B2XJV4BIGyWSLA2INHDAlfXMdzxxqodzLxZI3OL81QfDZWD5jTsaNuNomPHLDq40HLdeQk4OObaQmNAYeQ0Nph3ijTiTfcRZVmgr4PPUN/vOV5RyT1RmmzSml5AODIf7/bkuyQV+jAFLYD9frv92m0QyiU03kR/jtQy37xeenKTm+mL3AAcNl5xOspIaLzbNyQbDBNtaQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/30/26 03:53, Ye Liu wrote: > The last_migrate_reason field uses -1 as a sentinel value to mean "no > migration has happened". Replace the four bare -1 occurrences by > adding a proper MR_NEVER member to enum migrate_reason, defining a > corresponding "never_migrated" string in the MIGRATE_REASON trace > macro, and removing the local MIGRATE_REASON_NONE define. > > No functional change. > > Signed-off-by: Ye Liu Reviewed-by: Vlastimil Babka (SUSE) > --- > include/linux/migrate_mode.h | 1 + > include/trace/events/migrate.h | 3 ++- > mm/page_owner.c | 8 ++++---- > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/include/linux/migrate_mode.h b/include/linux/migrate_mode.h > index 265c4328b36a..05102d4d2490 100644 > --- a/include/linux/migrate_mode.h > +++ b/include/linux/migrate_mode.h > @@ -25,6 +25,7 @@ enum migrate_reason { > MR_LONGTERM_PIN, > MR_DEMOTION, > MR_DAMON, > + MR_NEVER, /* page has never been migrated */ > MR_TYPES > }; > > diff --git a/include/trace/events/migrate.h b/include/trace/events/migrate.h > index cd01dd7b3640..11bc0aa14c7e 100644 > --- a/include/trace/events/migrate.h > +++ b/include/trace/events/migrate.h > @@ -23,7 +23,8 @@ > EM( MR_CONTIG_RANGE, "contig_range") \ > EM( MR_LONGTERM_PIN, "longterm_pin") \ > EM( MR_DEMOTION, "demotion") \ > - EMe(MR_DAMON, "damon") > + EM( MR_DAMON, "damon") \ > + EMe(MR_NEVER, "never_migrated") > > /* > * First define the enums in the above macros to be exported to userspace > diff --git a/mm/page_owner.c b/mm/page_owner.c > index 342549891a8d..c2f43ab860eb 100644 > --- a/mm/page_owner.c > +++ b/mm/page_owner.c > @@ -339,7 +339,7 @@ noinline void __set_page_owner(struct page *page, unsigned short order, > depot_stack_handle_t handle; > > handle = save_stack(gfp_mask); > - __update_page_owner_handle(page, handle, order, gfp_mask, -1, > + __update_page_owner_handle(page, handle, order, gfp_mask, MR_NEVER, > ts_nsec, current->pid, current->tgid, > current->comm); > inc_stack_record_count(handle, gfp_mask, 1 << order); > @@ -596,7 +596,7 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, > if (ret >= count) > goto err; > > - if (page_owner->last_migrate_reason != -1) { > + if (page_owner->last_migrate_reason != MR_NEVER) { > ret += scnprintf(kbuf + ret, count - ret, > "Page has been migrated, last migrate reason: %s\n", > migrate_reason_names[page_owner->last_migrate_reason]); > @@ -667,7 +667,7 @@ void __dump_page_owner(const struct page *page) > stack_depot_print(handle); > } > > - if (page_owner->last_migrate_reason != -1) > + if (page_owner->last_migrate_reason != MR_NEVER) > pr_alert("page has been migrated, last migrate reason: %s\n", > migrate_reason_names[page_owner->last_migrate_reason]); > page_ext_put(page_ext); > @@ -826,7 +826,7 @@ static void init_pages_in_zone(struct zone *zone) > > /* Found early allocated page */ > __update_page_owner_handle(page, early_handle, 0, 0, > - -1, local_clock(), current->pid, > + MR_NEVER, local_clock(), current->pid, > current->tgid, current->comm); > count++; > ext_put_continue: