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 9BB7BC43334 for ; Thu, 23 Jun 2022 18:43:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1D84E8E0182; Thu, 23 Jun 2022 14:43:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1877E8E0144; Thu, 23 Jun 2022 14:43:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 04EC88E0182; Thu, 23 Jun 2022 14:43:12 -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 E694F8E0144 for ; Thu, 23 Jun 2022 14:43:12 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id AE0BA35AE5 for ; Thu, 23 Jun 2022 18:43:07 +0000 (UTC) X-FDA: 79610372814.19.14C7499 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf22.hostedemail.com (Postfix) with ESMTP id 3A362C00BE for ; Thu, 23 Jun 2022 18:43:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656009760; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1pPnDVr8A7fc4TlxGwEptvcXmBzoTYlHJlZ/bWXrkpw=; b=Gx7AcTQZbtEwb4MGNW4b/qwugOQrJG70TbvIPtJJeIHo5eY3zPSyPIqx1TcG+yd2XAkOfQ huznaDMuuoxrbId/nf7qzuRHd6+SQb3TIiTbETFpL7yXh7HVwOCSv21oi6yxdZpxRjH264 7Do9N5AHq8sKeHb6wcqPNV/gnNgOpD8= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-606-zq4bDmBlNLGHFoB_344-HA-1; Thu, 23 Jun 2022 14:42:39 -0400 X-MC-Unique: zq4bDmBlNLGHFoB_344-HA-1 Received: by mail-wm1-f71.google.com with SMTP id i184-20020a1c3bc1000000b003a026f48333so7001wma.4 for ; Thu, 23 Jun 2022 11:42:38 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:references:from:organization:in-reply-to :content-transfer-encoding; bh=1pPnDVr8A7fc4TlxGwEptvcXmBzoTYlHJlZ/bWXrkpw=; b=3q9bPQnsuPiJWJnwelG7RV7Y6TettQtPoPHeZzB6UFzr8d58RC+n44MBBmcDq5Bpqt Rut4O2zkfe3q3ISWztqwyxn7p/Dd+p5Ir+qriUtXbilsCkXfPQcFHGq0u7IgO0wt4cTk NZd7khR1MyeIFvePOanp7XuKv5ul0f7CKA7ArMh8K98B4diCkbjEkclfcw+LaXyuU+3z KBSaSkDU8WbSo3VL++5nP38HlYagesI4dVFnvOUsQgJqTdD2bBi78VWCQTmKwONfTo1t H+XdF6Yr8Zg9zFaU/OschB3hT7mZcV0VT+NQlnQSwtud+ZBb8q9ypW5MR/BMjeVJJt8y zrKA== X-Gm-Message-State: AJIora95o/5DA+YP+OnfszTavJL6rcePNSDx4qMjArpPTBNdG4Ul9/Qt UUVz/p/Oq7vb9a1smvbYyuSoGQ0/uNMyW0MaVLX4j7D7FzXlaRjT0vowqzZ2ayJYUc24xZzSgxA hYMSeW+FP8lQ= X-Received: by 2002:a1c:27c6:0:b0:39c:34a5:9f88 with SMTP id n189-20020a1c27c6000000b0039c34a59f88mr5779170wmn.94.1656009757879; Thu, 23 Jun 2022 11:42:37 -0700 (PDT) X-Google-Smtp-Source: AGRyM1vCYmS71wE+ogs05XCnQfh76mPTto8pHRA8OFiPThvd3cnvwh7U5PynNAXyZn0n0AvLY/OLCQ== X-Received: by 2002:a1c:27c6:0:b0:39c:34a5:9f88 with SMTP id n189-20020a1c27c6000000b0039c34a59f88mr5779147wmn.94.1656009757628; Thu, 23 Jun 2022 11:42:37 -0700 (PDT) Received: from ?IPV6:2003:cb:c704:b100:7694:f34e:d0dd:95e7? (p200300cbc704b1007694f34ed0dd95e7.dip0.t-ipconnect.de. [2003:cb:c704:b100:7694:f34e:d0dd:95e7]) by smtp.gmail.com with ESMTPSA id e9-20020a5d4e89000000b0021a3a87fda9sm144112wru.47.2022.06.23.11.42.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Jun 2022 11:42:37 -0700 (PDT) Message-ID: <5787e664-73c6-4ab0-451e-2b0f3becb6ae@redhat.com> Date: Thu, 23 Jun 2022 20:42:36 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: [PATCH v10 14/69] kernel/fork: use maple tree for dup_mmap() during forking To: Liam Howlett , "maple-tree@lists.infradead.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton , "damon @ lists . linux . dev" , SeongJae Park References: <20220621204632.3370049-1-Liam.Howlett@oracle.com> <20220621204632.3370049-15-Liam.Howlett@oracle.com> From: David Hildenbrand Organization: Red Hat In-Reply-To: <20220621204632.3370049-15-Liam.Howlett@oracle.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Gx7AcTQZ; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf22.hostedemail.com: domain of david@redhat.com has no SPF policy when checking 170.10.133.124) smtp.mailfrom=david@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656009787; a=rsa-sha256; cv=none; b=sdOKe9sIiDxkvEb/BkES4y5TtCRWLl/tq6S+dmLAIVU6d6ZwAP0sxPmQom/C8vHrbIuo+p YBc1fvtazlN8SLjvOaCKKzq3obCrINHTaxV8t33bScFgKNsX2LMX4m+j45CaGARNTR+z7I 9CTTRmiWD+u5eYgxjkrHQ1Sk+v/JFFE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656009787; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to: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=1pPnDVr8A7fc4TlxGwEptvcXmBzoTYlHJlZ/bWXrkpw=; b=f5W/Q9fPYfvF6XwPSI/UbpQiKxxJOG/6bmenZ+I4LQj+w/u0Z8ZJXV7CZeRvi84r06ogew EL/DXRLy1v52kscn+FfKuLdGgTHR1tLCKb/lKy4oHTmV0mInnRdPndl7dQsksi2MaHpHen 5XL9PDAkmhZALaxee+YfRzV2h8svRTE= X-Stat-Signature: wxuu8nttta9xgsufbn4iy3r95jg7djpy X-Rspamd-Server: rspam08 X-Rspam-User: X-Rspamd-Queue-Id: 3A362C00BE Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Gx7AcTQZ; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf22.hostedemail.com: domain of david@redhat.com has no SPF policy when checking 170.10.133.124) smtp.mailfrom=david@redhat.com X-HE-Tag: 1656009787-239156 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 21.06.22 22:46, Liam Howlett wrote: > From: "Liam R. Howlett" > > The maple tree was already tracking VMAs in this function by an earlier > commit, but the rbtree iterator was being used to iterate the list. > Change the iterator to use a maple tree native iterator and switch to the > maple tree advanced API to avoid multiple walks of the tree during insert > operations. Unexport the now-unused vma_store() function. > > For performance reasons we bulk allocate the maple tree nodes. The node > calculations are done internally to the tree and use the VMA count and > assume the worst-case node requirements. The VM_DONT_COPY flag does not > allow for the most efficient copy method of the tree and so a bulk loading > algorithm is used. You could track the #VM_DONT_COPY per mm and optimize? Do you have that planned or maybe it already is part of this patch set? :) > > Link: https://lkml.kernel.org/r/20220504010716.661115-16-Liam.Howlett@oracle.com > Signed-off-by: Liam R. Howlett > Signed-off-by: Matthew Wilcox (Oracle) > Acked-by: Vlastimil Babka > Cc: Catalin Marinas > Cc: David Howells > Cc: SeongJae Park > Cc: Will Deacon > Cc: Davidlohr Bueso > Signed-off-by: Andrew Morton > --- > include/linux/mm.h | 2 -- > kernel/fork.c | 12 +++++++++--- > 2 files changed, 9 insertions(+), 5 deletions(-) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index f22c6f71a18c..27fa36a7c093 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -2612,8 +2612,6 @@ extern bool arch_has_descending_max_zone_pfns(void); > /* nommu.c */ > extern atomic_long_t mmap_pages_allocated; > extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t); > -/* mmap.c */ > -void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas); > > /* interval_tree.c */ > void vma_interval_tree_insert(struct vm_area_struct *node, > diff --git a/kernel/fork.c b/kernel/fork.c > index 1840da0732f6..4ecca79556eb 100644 > --- a/kernel/fork.c > +++ b/kernel/fork.c > @@ -583,9 +583,10 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, > struct vm_area_struct *mpnt, *tmp, *prev, **pprev; > struct rb_node **rb_link, *rb_parent; > int retval; > - unsigned long charge; > - LIST_HEAD(uf); > + unsigned long charge = 0; ^ why that change? > + MA_STATE(old_mas, &oldmm->mm_mt, 0, 0); > MA_STATE(mas, &mm->mm_mt, 0, 0); > + LIST_HEAD(uf); ^ why that reshuffling? > > uprobe_start_dup_mmap(); > if (mmap_write_lock_killable(oldmm)) { > @@ -620,7 +621,12 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, > goto out; > > prev = NULL; > - for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { > + > + retval = mas_expected_entries(&mas, oldmm->map_count); > + if (retval) > + goto out; mas_expected_entries is a fancy function :) > + > + mas_for_each(&old_mas, mpnt, ULONG_MAX) { > struct file *file; > > if (mpnt->vm_flags & VM_DONTCOPY) { -- Thanks, David / dhildenb