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 41F79C433EF for ; Wed, 19 Jan 2022 17:39:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C1E726B0072; Wed, 19 Jan 2022 12:39:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BCE066B0073; Wed, 19 Jan 2022 12:39:19 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A73D36B0074; Wed, 19 Jan 2022 12:39:19 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0134.hostedemail.com [216.40.44.134]) by kanga.kvack.org (Postfix) with ESMTP id 98F886B0072 for ; Wed, 19 Jan 2022 12:39:19 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 50EB1180B3DE3 for ; Wed, 19 Jan 2022 17:39:19 +0000 (UTC) X-FDA: 79047748038.05.A74C846 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf04.hostedemail.com (Postfix) with ESMTP id CF1244005D for ; Wed, 19 Jan 2022 17:39:18 +0000 (UTC) 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 628531F3BB; Wed, 19 Jan 2022 17:39:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1642613957; 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=7Qro480AA4cZI77Tk3jaiJ1tQjLMVKSsBsFc+NketX4=; b=nuViXcdglk4sy3cQXfASyPJJ0EiEKAulHnFl7H9iegiLT8IZrcLLIyIn9lkhpjozMU1brh IVAzVtqEitfYx4SJW19Q4vk3Ied0ewoe0Go9CANxGFiSTg8JUkORWvfBw32JntEWnvvfb4 aAicAR1vJZfdczEInsNKAuZEPMLcr/U= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1642613957; 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=7Qro480AA4cZI77Tk3jaiJ1tQjLMVKSsBsFc+NketX4=; b=Df4Cskz2BNBpSVEvVy5TQq506nWGmGF2EsOGwJ2P+jwC94jpiV+IoK9Wwu+n1mcCcwWX5L TtRZrARflli7bdAg== 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 1845213E15; Wed, 19 Jan 2022 17:39:17 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id kIwiBcVM6GHGRgAAMHmgww (envelope-from ); Wed, 19 Jan 2022 17:39:17 +0000 Message-ID: Date: Wed, 19 Jan 2022 18:39:16 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH v4 50/66] mm/gup: Use maple tree navigation instead of linked list Content-Language: en-US To: Liam Howlett , "maple-tree@lists.infradead.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton Cc: Song Liu , Davidlohr Bueso , "Paul E . McKenney" , Matthew Wilcox , Laurent Dufour , David Rientjes , Axel Rasmussen , Suren Baghdasaryan , Rik van Riel , Peter Zijlstra , Michel Lespinasse , Jerome Glisse , Minchan Kim , Joel Fernandes , Rom Lemarchand References: <20211201142918.921493-1-Liam.Howlett@oracle.com> <20211201142918.921493-51-Liam.Howlett@oracle.com> From: Vlastimil Babka In-Reply-To: <20211201142918.921493-51-Liam.Howlett@oracle.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: CF1244005D X-Stat-Signature: 97qetuh56fw4bmyo8n8ym68sfnq7snqs Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=nuViXcdg; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=Df4Cskz2; dmarc=none; spf=pass (imf04.hostedemail.com: domain of vbabka@suse.cz designates 195.135.220.29 as permitted sender) smtp.mailfrom=vbabka@suse.cz X-Rspamd-Server: rspam06 X-HE-Tag: 1642613958-499262 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 12/1/21 15:30, Liam Howlett wrote: > From: "Liam R. Howlett" Empty message. > Signed-off-by: Liam R. Howlett > --- > mm/gup.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) > > diff --git a/mm/gup.c b/mm/gup.c > index 2c51e9748a6a..60892e5df6a2 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -1570,7 +1570,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors) > long ret = 0; > > end = start + len; > - > for (nstart = start; nstart < end; nstart = nend) { > /* > * We want to fault in pages for [nstart; end) address range. > @@ -1579,10 +1578,10 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors) > if (!locked) { > locked = 1; > mmap_read_lock(mm); > - vma = find_vma(mm, nstart); > + vma = find_vma_intersection(mm, start, end); Is it ok to use start instead of nstart? At least theoretically, populate_vma_page_range() called later can reset locked to 0, so !locked doesn't guarantee we are in the first iteration? > } else if (nstart >= vma->vm_end) > - vma = vma->vm_next; > - if (!vma || vma->vm_start >= end) > + vma = find_vma(mm, vma->vm_end); > + if (!vma) > break; > /* > * Set [nstart; nend) to intersection of desired address