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 745ECC001DB for ; Tue, 8 Aug 2023 11:17:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DBF0F6B0071; Tue, 8 Aug 2023 07:17:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D6E9F6B0074; Tue, 8 Aug 2023 07:17:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C37838D0001; Tue, 8 Aug 2023 07:17:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id B37896B0071 for ; Tue, 8 Aug 2023 07:17:43 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 6D50816067A for ; Tue, 8 Aug 2023 11:17:43 +0000 (UTC) X-FDA: 81100687206.09.5C319F8 Received: from mail-oo1-f46.google.com (mail-oo1-f46.google.com [209.85.161.46]) by imf22.hostedemail.com (Postfix) with ESMTP id C35D2C0013 for ; Tue, 8 Aug 2023 11:17:40 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=bytedance.com header.s=google header.b=O2g0oBYt; dmarc=pass (policy=quarantine) header.from=bytedance.com; spf=pass (imf22.hostedemail.com: domain of zhangpeng.00@bytedance.com designates 209.85.161.46 as permitted sender) smtp.mailfrom=zhangpeng.00@bytedance.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1691493461; 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=rzvjGxgEq+LtZZdyPTPHKgoOYqzBn/ItwHuccLXsw3U=; b=oIo/kUf9IZhgm47nVKej7tlQHsZOK4spTtpK2mnvzMwlPZaCxgu4draYLTV9eD5mlGVGEz lOyBUE8CrrUWnG6P1OkMdORuHTrY2UJTYLbilFnfFHyv6T7QTje9QNq5HKNsNOXXRcJopb P2CVTzu+cjA9qcQG4fMdB+0RWpjmXs8= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=bytedance.com header.s=google header.b=O2g0oBYt; dmarc=pass (policy=quarantine) header.from=bytedance.com; spf=pass (imf22.hostedemail.com: domain of zhangpeng.00@bytedance.com designates 209.85.161.46 as permitted sender) smtp.mailfrom=zhangpeng.00@bytedance.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1691493461; a=rsa-sha256; cv=none; b=yZk+bxK8AYmQsAcxPEPczc6PsubePfwpmRYnlMBN7tA3SxqORKsyWxOiG9dJkSBSsWFQJr D7LKY4vwdTKTZuTPwLfAVoqPbbYb93rvM+roqQB93ouEDKNOzAjE7QetvP+sTXhhX98+uC 2deZ0n6DRb7tesGuNCE5Jkwe4GBHP8o= Received: by mail-oo1-f46.google.com with SMTP id 006d021491bc7-56c7eb17945so3321563eaf.2 for ; Tue, 08 Aug 2023 04:17:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1691493459; x=1692098259; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:from:to:cc:subject:date :message-id:reply-to; bh=rzvjGxgEq+LtZZdyPTPHKgoOYqzBn/ItwHuccLXsw3U=; b=O2g0oBYtTpm72ygoLDgb3M2aso0xNg3zwsRoBSbDtJVXFUYMuIiJoGLoxuOjba9ul5 4mMSUvqmQCXjijQCqqFqW/4b1oqafP8mTNqtysRnez2iiRnsp1JpqyY5QmSa86LKuOqf 0Ij2QnlGgwpYgkjNaJCqekTmazBYgDCSmP1s65wDpkQs8hDZuYIu2GIvWgilN0K7l4gi ui+sZ+qIH+qUcXeLunP1r+woQyMpiHZnp1ONqdJJ6hjNyxTvuZjtT1LYAqu/nc8tJecg O5xfwL3Drlsvg+pmXIIIWRoBy9dRwvjZreY59sODFNWAzNFXMpfOtWRem+wJWZ8i1AKU +WCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691493459; x=1692098259; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=rzvjGxgEq+LtZZdyPTPHKgoOYqzBn/ItwHuccLXsw3U=; b=JT95nFHCuHwPryAJwzTI03Y7Q5Dq1x5S4Hg6wUxSeJ3512hpOhRV5JRyEB9ZVmlRp8 WNZKICMQQErVQM11KXk7SJEZmPWmtSv5L1pFo6r37BeVajdILQfoucVt7dWiHqZBohcL TK7Q/zSFsINLSssUD0VtkTwoRYEwECTJlMPr3yTLEQG2GiTOvpHukMd8CnM/VWJVEjuP 7fc64EisjLUa6LxobJBZDHmd4AtYKytYpTgD/d0viCdCabDXya8oqPR6PeKRt+ADOl12 4wHTzfzjPeWa8cmu+nHvZQYlaKPfyUrVan9H2QX7b1XiVzI4pEcMyPIx43FY2uA1HZoa IA3A== X-Gm-Message-State: AOJu0YyHnZnuq4FM+jzIEvSY0QoKeIkGLimeVOlslN7TlfMOMt12gT/y Z8gN7xP6GCvPEY7olp7a4Oe2rw== X-Google-Smtp-Source: AGHT+IF/38k+mHYDsiCV9q5ja1BmiVsvVPQRkz7QNU8NMvABvumJfQv6Cb+Dkh3TgtDABWaEDoiMaQ== X-Received: by 2002:a05:6808:f8d:b0:3a7:3ea1:b5a0 with SMTP id o13-20020a0568080f8d00b003a73ea1b5a0mr14696027oiw.47.1691493459612; Tue, 08 Aug 2023 04:17:39 -0700 (PDT) Received: from [10.90.34.137] ([203.208.167.146]) by smtp.gmail.com with ESMTPSA id 30-20020a17090a005e00b0025023726fc4sm11179299pjb.26.2023.08.08.04.17.35 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Aug 2023 04:17:39 -0700 (PDT) Message-ID: <853af8fa-0cef-b00b-3fd6-9780a2008050@bytedance.com> Date: Tue, 8 Aug 2023 19:17:31 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.14.0 Subject: Re: [RFC v1 4/5] maple_tree: avoid bulk alloc/free to use percpu array more To: Vlastimil Babka Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>, Joonsoo Kim , Pekka Enberg , David Rientjes , Christoph Lameter , "Liam R. Howlett" , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org, patches@lists.linux.dev, Matthew Wilcox References: <20230808095342.12637-7-vbabka@suse.cz> <20230808095342.12637-11-vbabka@suse.cz> From: Peng Zhang In-Reply-To: <20230808095342.12637-11-vbabka@suse.cz> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: C35D2C0013 X-Stat-Signature: ms3738oh9jg3bnzjbix83np8wmzmxkce X-Rspam-User: X-HE-Tag: 1691493460-124655 X-HE-Meta: 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 uo63pBti K1dTxNG4GgoxJOOFh9z7BXxurwkrzKr0j7GKeyyQC3BT035tSWZrLrlYi21uDlqf+7KH/ul8nY5EnhcJEYdTSmRdCwUnU57824QZrl7C9XzuCclV8xJ1GKr9fvD837IQQKKD0LHsNsnF7zrQIMNKdUaz3wOjUa55fG8L/Js37V0LINzIeUfsohKWwogP0AhPahIIyO4JLtToOTnGSr6G/1H0oS1JJHY2d7E2QsTBj43vS1Jm9Qz4FyeIf+luDXJ5SdMX6r0iqmvRX1RpT0tr7QsK/QqpoAxtDuGxJAfmMYjHTy8DwCeKZwRX8vTo6AuWVuWJUlK4lMq1+Hax11Ln+a5TmX/yNs8MIxCA/ut2mkTgIXcCsIJwr4T2SkF1KBKBdhVosZ17CoXzlnnmfnr/qzR8zz/RYK6STq/rO/zgyVqdf1pqrWkQ3FAXQdEaZho23mcSVMQS76DlyPzo8r0irz++tQAvxZMDlHps8+f4S6PhQZvQ= 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: 在 2023/8/8 17:53, Vlastimil Babka 写道: > Using bulk alloc/free on a cache with percpu array should not be > necessary and the bulk alloc actually bypasses the array (the prefill > functionality currently relies on this). > > The simplest change is just to convert the respective maple tree > wrappers to do a loop of normal alloc/free. > --- > lib/maple_tree.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/lib/maple_tree.c b/lib/maple_tree.c > index 1196d0a17f03..7a8e7c467d7c 100644 > --- a/lib/maple_tree.c > +++ b/lib/maple_tree.c > @@ -161,12 +161,19 @@ static inline struct maple_node *mt_alloc_one(gfp_t gfp) > > static inline int mt_alloc_bulk(gfp_t gfp, size_t size, void **nodes) > { > - return kmem_cache_alloc_bulk(maple_node_cache, gfp, size, nodes); > + int allocated = 0; > + for (size_t i = 0; i < size; i++) { > + nodes[i] = kmem_cache_alloc(maple_node_cache, gfp); > + if (nodes[i]) If the i-th allocation fails, node[i] will be NULL. This is wrong. We'd better guarantee that mt_alloc_bulk() allocates completely successfully, or returns 0. The following cases are not allowed: nodes: [addr1][addr2][NULL][addr3]. > + allocated++; > + } > + return allocated; > } > > static inline void mt_free_bulk(size_t size, void __rcu **nodes) > { > - kmem_cache_free_bulk(maple_node_cache, size, (void **)nodes); > + for (size_t i = 0; i < size; i++) > + kmem_cache_free(maple_node_cache, nodes[i]); > } > > static void mt_free_rcu(struct rcu_head *head)