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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A4B2C6FD18 for ; Wed, 29 Mar 2023 08:41:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 107836B0072; Wed, 29 Mar 2023 04:41:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0931C6B0074; Wed, 29 Mar 2023 04:41:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E9A586B0075; Wed, 29 Mar 2023 04:41:56 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id D64F06B0072 for ; Wed, 29 Mar 2023 04:41:56 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 727C780A17 for ; Wed, 29 Mar 2023 08:41:56 +0000 (UTC) X-FDA: 80621293032.02.C8FD7A3 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf22.hostedemail.com (Postfix) with ESMTP id 5849CC000C for ; Wed, 29 Mar 2023 08:41:54 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=LUVj+4Ke; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=b8+5k1cj; spf=pass (imf22.hostedemail.com: domain of vbabka@suse.cz designates 195.135.220.29 as permitted sender) smtp.mailfrom=vbabka@suse.cz; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1680079314; a=rsa-sha256; cv=none; b=WEKEBrHPgWa1Yy8uwt8f4Nngt54uROp10lM0juPEr3RZ1YZf+FW4ow+rlQ6VnlKeCeFmKX N1fX5sGuzDseB31BzfE3A0KoWN0sTrB2zrZV50kSsbEXvy8hkzHQZdmVbzTdWJRxFmQtYU ZAczLidTFAEAMMJHS4FZG4nLkxANyMg= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=LUVj+4Ke; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=b8+5k1cj; spf=pass (imf22.hostedemail.com: domain of vbabka@suse.cz designates 195.135.220.29 as permitted sender) smtp.mailfrom=vbabka@suse.cz; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1680079314; 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=FXNeQEeNkO9Z+oDPQiH/Ygm1gn1aQwVSYkquaLAzwlA=; b=BmtqLDI8GC2z+QRh0VzjrT/3txZBm9ELU7ZMCKGbY6EOxi0Gd+42YByEawyDZUoznv/lDN Tku5M284ztCctiC+/XJqlp0BB262jxkpE/mMsDd3Fb5wXiiAi5d1bo7+mJTZRFtxSJgf/+ ay6Np4xPLt0UboiQoeKtjHeBwA2qDE4= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id CAC831FDF3; Wed, 29 Mar 2023 08:41:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1680079312; h=from:from:reply-to: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=FXNeQEeNkO9Z+oDPQiH/Ygm1gn1aQwVSYkquaLAzwlA=; b=LUVj+4KeuB2yvYNm15M0kJNlEkkTHl61wObJ0NeETKr2EQ8596eyWXIxI0wWssy36Q+LwV FRcYMZVTghWFqYMql9w+AXL4wZZ9guThsu4rznrzpyhXSs/rUXyQ9iGYQUF+QT6N5CSk9F iJyQzPwcSTv99ZZY0QB+ZMvvfysZXis= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1680079312; h=from:from:reply-to: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=FXNeQEeNkO9Z+oDPQiH/Ygm1gn1aQwVSYkquaLAzwlA=; b=b8+5k1cjnJfonOpuSjz3VtwXV2d48GqUcCFYzjm/8FadUQaKJktk8tbfJ4nlPyFi14BOGR gngJBpU/t+aqd0Dg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 9293E139D3; Wed, 29 Mar 2023 08:41:52 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id KV4GItD5I2RjagAAMHmgww (envelope-from ); Wed, 29 Mar 2023 08:41:52 +0000 Message-ID: <4f1096f0-cb6e-7cd2-5f41-c5e4b53fa407@suse.cz> Date: Wed, 29 Mar 2023 10:41:52 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH] mm/slub: Reduce memory consumption in extreme scenarios Content-Language: en-US To: "chenjun (AM)" , Mike Rapoport Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "cl@linux.com" , "penberg@kernel.org" , "rientjes@google.com" , "iamjoonsoo.kim@lge.com" , "akpm@linux-foundation.org" , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "xuqiang (M)" , "Wangkefeng (OS Kernel Lab)" , Michal Hocko , Mel Gorman References: <20230314123403.100158-1-chenjun102@huawei.com> <0cad1ff3-8339-a3eb-fc36-c8bda1392451@suse.cz> <344c7521d72e4107b451c19b329e9864@huawei.com> <8c700468-245d-72e9-99e7-b99d4547e6d8@suse.cz> <015855b3-ced3-8d84-e21d-cc6ce112b556@suse.cz> From: Vlastimil Babka In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Queue-Id: 5849CC000C X-Rspamd-Server: rspam01 X-Stat-Signature: xy8bc7uhjfii75pt8jtmcp3dqspr136i X-HE-Tag: 1680079314-9590 X-HE-Meta: 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 WHhN4HzW T+zwVOpb0h4lHo9LyGj4q0SgVSnZ2VlzhaqEKy7vyLcOF74gmvwVd8f+qgd9XGfdsnIoXlqetUZncMMX3wn/dY5nZtqqjPZGRYffMXcZn0lVNqM1A28wIlwMPn0kVCka1O+oF0AkPXYHX3Gx1c4ufFOSz4s4ciRQ37e9OAOECTNwyD9DJ+9AGhviJKzzLAUMjkoBfVAJ396wp7Qfm6MxsHCTVuujiNUedBY8PzulPnm8+xnWp4QmA0p7igKnH2QlfdjKlAtgVqXausZ5NPK6ZhiTsxkOxIa5f4wzbmVzVSbfUhe9kbg3mUjDGlAB43f/fJm28N7iHKb/bkLA= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 3/21/23 10:30, chenjun (AM) wrote: > 在 2023/3/20 17:12, Mike Rapoport 写道: >>>> >>>> If we ignore __GFP_ZERO passed by kzalloc， kzalloc will not work. >>>> Could we just unmask __GFP_RECLAIMABLE | __GFP_RECLAIM? >>>> >>>> pc.flags &= ~(__GFP_RECLAIMABLE | __GFP_RECLAIM) >>>> pc.flags |= __GFP_THISNODE >>> >>> __GFP_RECLAIMABLE would be wrong, but also ignored as new_slab() does: >>> flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK) >>> >>> which would filter out __GFP_ZERO as well. That's not a problem as kzalloc() >>> will zero out the individual allocated objects, so it doesn't matter if we >>> don't zero out the whole slab page. >>> >>> But I wonder, if we're not past due time for a helper e.g. >>> gfp_opportunistic(flags) that would turn any allocation flags to a >>> GFP_NOWAIT while keeping the rest of relevant flags intact, and thus there >>> would be one canonical way to do it - I'm sure there's a number of places >>> with their own variants now? >>> With such helper we'd just add __GFP_THISNODE to the result here as that's >>> specific to this particular opportunistic allocation. >> >> I like the idea, but maybe gfp_no_reclaim() would be clearer? >> > > #define gfp_no_reclaim(gfpflag) (gfpflag & ~__GFP_DIRECT_RECLAIM) I hoped for more feedback on the idea, but it's probably best proposed outside of this slub-specific thread, so we could go for an open-coded solution in slub for now. Also just masking out __GFP_DIRECT_RECLAIM wouldn't be sufficient in any case for the general solution/ > And here, > > pc.flags = gfp_no_reclaim(gfpflags) | __GFP_THISNODE. I'd still suggest as earlier: pc.flags = GFP_NOWAIT | __GFP_NOWARN |__GFP_THISNODE; > Do I get it right？