Received: by 2002:a05:7412:bbc7:b0:fc:a2b0:25d7 with SMTP id kh7csp909275rdb; Fri, 2 Feb 2024 07:38:59 -0800 (PST) X-Google-Smtp-Source: AGHT+IHce+4+tOCqam95D3VJneCDFSh17Q3TvPPkU+e+ptZnIQpe5UmVpqwoHhPfEkc60TQX5Osl X-Received: by 2002:a17:903:11d1:b0:1d4:47d4:82b4 with SMTP id q17-20020a17090311d100b001d447d482b4mr9950095plh.15.1706888339197; Fri, 02 Feb 2024 07:38:59 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1706888339; cv=pass; d=google.com; s=arc-20160816; b=Z5u/OibK9SygapCjAgP6w5f+YIa9Ne13Z5PyBgH7PCFTST4MsUGy4A/nf1eSyT2W+r t8hH3IsAnUN2XmYBuZr/1XLeViCw7FTFGrIMgOpiU+I28LrAynQDyO23X/KUDa54mVda otYIxFOa7XMZEw4GWHeUytAOCkk9RrG3n9KtVQoPWmjzJPuURWLcscboJbtg/ZmiuY7C hTvEBsC9vLSVUgi85yEhkbYKpO0vt03giUaFdYD9SWNBfJD9NzHnJNbqiggOnGz8JaBN aofZeWKl/bOjSdPgX1xJ2f6xc9PB134dMnw/05SIkFZBiJZcvsyL61RVHj3aB5ytFUIV l/cQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=in-reply-to:content-disposition:mime-version:list-unsubscribe :list-subscribe:list-id:precedence:references:message-id:subject:cc :to:from:date:dkim-signature:dkim-signature; bh=7DD5NcDaE4KXkL73aEaoSi9tMEuvt0oHfZv8FAecTdE=; fh=v4YHwiNWJMcXv329zmudhLXKTR0z+//44PCgOYb3aR4=; b=C5FzTr41Zh4suE3NTmNPf1ghVXx+YtqvxKNPDXji3Fq6JIBwwqKjbH2F6+GKkKjfjf 2Roj5Iss9QiruNU1F6KPuIC/207CQTrGMazXV82ZBey+10xBEGZzYzd3FvwNtiA8J5nt Zs6SiirPMhGYP5e/sJdH2Ao5uUdSJtus+6syAdMiN5dY9b5Dk1TUUGnU6NuskQA/u8vm yXFjI3n13n/Wvco0zYi+wF+aNo5cXIHzdkDYgP075rM0m631jUVTH0Ty8Ca6CVARqrZV 0ItuqsIq+jRF98iPkhS5wuMBvZDGgq0hqcXxPvEkjK+UDGou6gK8Rez67Dqki5MwhUYS 2EhQ==; dara=google.com ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@suse.com header.s=susede1 header.b="JE3/OF6P"; dkim=pass header.i=@suse.com header.s=susede1 header.b="JE3/OF6P"; arc=pass (i=1 spf=pass spfdomain=suse.com dkim=pass dkdomain=suse.com dkim=pass dkdomain=suse.com dmarc=pass fromdomain=suse.com); spf=pass (google.com: domain of linux-kernel+bounces-50031-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) smtp.mailfrom="linux-kernel+bounces-50031-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=suse.com X-Forwarded-Encrypted: i=1; AJvYcCVDKwJzoiOIwbjdMvcoMvy8/dp9tJZrm2jWhhxft7o06uStbAhCCWPLJZoes22LOlAoeW4wo4lSm2GzBRDSpTSnsVQfXQGWQdzI9dIC8A== Return-Path: Received: from sv.mirrors.kernel.org (sv.mirrors.kernel.org. [139.178.88.99]) by mx.google.com with ESMTPS id q9-20020a170902dac900b001d916995426si1969734plx.92.2024.02.02.07.38.58 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Feb 2024 07:38:59 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-50031-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99; Authentication-Results: mx.google.com; dkim=pass header.i=@suse.com header.s=susede1 header.b="JE3/OF6P"; dkim=pass header.i=@suse.com header.s=susede1 header.b="JE3/OF6P"; arc=pass (i=1 spf=pass spfdomain=suse.com dkim=pass dkdomain=suse.com dkim=pass dkdomain=suse.com dmarc=pass fromdomain=suse.com); spf=pass (google.com: domain of linux-kernel+bounces-50031-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) smtp.mailfrom="linux-kernel+bounces-50031-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=suse.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id C6E79288E2C for ; Fri, 2 Feb 2024 15:38:58 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D7FE01468E6; Fri, 2 Feb 2024 15:38:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="JE3/OF6P"; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="JE3/OF6P" Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.223.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 52CBE1872 for ; Fri, 2 Feb 2024 15:38:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.135.223.130 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706888333; cv=none; b=QTYn8UG/3OKoa3gxezJF2TxJSpNBx/XC8e9nvatf5iuOZKMGjl+7lhlbVPvRH/bJj1HVfGDurSxwHxyfEfVj6ouN0t46K5OVVn1xpVGrSvzGBdZt9+zUjSXOgQ5aMoIOlcSqgxnCrzRiNR8dU3dyOoucKWbjeH3fGqH6PBt655U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706888333; c=relaxed/simple; bh=UYblkh2pH0hBjmVVJDctM71dsCbLqTeguVKb8o0oNq0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=e8AtRM5AyfdowcMg+wDwCJOr0drI6GYW7wk1FYNu1zZ3GXJPNDuHyfXE/onZs3p1pVn8EZNzAuotRYDDvF9KvSpj4tCOB6MzG8s4uUz/2sEpOF8bBUslPluYb4kTXMtR+gFLO4qOh6difw9r6CaEQahpErGQ5UfWfbknPDiWdTs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b=JE3/OF6P; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b=JE3/OF6P; arc=none smtp.client-ip=195.135.223.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 3D71021E95; Fri, 2 Feb 2024 15:38:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1706888329; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=7DD5NcDaE4KXkL73aEaoSi9tMEuvt0oHfZv8FAecTdE=; b=JE3/OF6P/OICQQObQF+DQQ8eB5RUYQtXiBvl8Dn2OzA9BiY6zEjcozPa/dL3PdOzAJwq3g xtL/tF+edkLZESb51NpOwIykl3OsP5jOwq5aGwJOUcehIb5xdVk07tkJBGuN690O9tJJwp qmJ44rbfcdkW7XLFO8jmuAMJs+K2A5Q= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1706888329; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=7DD5NcDaE4KXkL73aEaoSi9tMEuvt0oHfZv8FAecTdE=; b=JE3/OF6P/OICQQObQF+DQQ8eB5RUYQtXiBvl8Dn2OzA9BiY6zEjcozPa/dL3PdOzAJwq3g xtL/tF+edkLZESb51NpOwIykl3OsP5jOwq5aGwJOUcehIb5xdVk07tkJBGuN690O9tJJwp qmJ44rbfcdkW7XLFO8jmuAMJs+K2A5Q= Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 201AC139AB; Fri, 2 Feb 2024 15:38:49 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 5RaJBokMvWXWMwAAD6G6ig (envelope-from ); Fri, 02 Feb 2024 15:38:49 +0000 Date: Fri, 2 Feb 2024 16:38:48 +0100 From: Michal Hocko To: Lance Yang Cc: akpm@linux-foundation.org, zokeefe@google.com, david@redhat.com, songmuchun@bytedance.com, shy828301@gmail.com, peterx@redhat.com, minchan@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] mm/khugepaged: skip copying lazyfree pages on collapse Message-ID: References: <20240201125226.28372-1-ioworker0@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Authentication-Results: smtp-out1.suse.de; dkim=pass header.d=suse.com header.s=susede1 header.b="JE3/OF6P" X-Spamd-Result: default: False [-2.13 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_ALLOW(-0.20)[suse.com:s=susede1]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DWL_DNSWL_BLOCKED(0.00)[suse.com:dkim]; RCVD_COUNT_THREE(0.00)[3]; DKIM_SIGNED(0.00)[suse.com:s=susede1]; DKIM_TRACE(0.00)[suse.com:+]; MX_GOOD(-0.01)[]; RCPT_COUNT_SEVEN(0.00)[10]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.com:dkim]; FREEMAIL_TO(0.00)[gmail.com]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_NOT_FQDN(0.50)[]; FREEMAIL_CC(0.00)[linux-foundation.org,google.com,redhat.com,bytedance.com,gmail.com,kernel.org,kvack.org,vger.kernel.org]; RCVD_TLS_ALL(0.00)[]; BAYES_HAM(-2.32)[96.85%] X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: 3D71021E95 X-Spam-Level: X-Spam-Score: -2.13 X-Spam-Flag: NO On Fri 02-02-24 22:52:49, Lance Yang wrote: > How about blocking khugepaged from > collapsing lazyfree pages? This way, > is it not better to keep the semantics > of MADV_FREE? I do not see any reason why. And you are not providing any actual reasoning either. Unless you have a very specific example in mind I do not think we want to change the current behavior. -- Michal Hocko SUSE Labs