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 123BBC001B0 for ; Wed, 16 Aug 2023 11:29:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9641A8D002D; Wed, 16 Aug 2023 07:29:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 911098D0001; Wed, 16 Aug 2023 07:29:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7D8828D002D; Wed, 16 Aug 2023 07:29:47 -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 6C3CF8D0001 for ; Wed, 16 Aug 2023 07:29:47 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 402CD80C25 for ; Wed, 16 Aug 2023 11:29:47 +0000 (UTC) X-FDA: 81129748014.26.8D79356 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by imf07.hostedemail.com (Postfix) with ESMTP id 6129140007 for ; Wed, 16 Aug 2023 11:29:45 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=collabora.com header.s=mail header.b=Dt8B2jZb; spf=pass (imf07.hostedemail.com: domain of usama.anjum@collabora.com designates 46.235.227.172 as permitted sender) smtp.mailfrom=usama.anjum@collabora.com; dmarc=pass (policy=quarantine) header.from=collabora.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1692185385; 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=t9jAWscM0kcKdIZJHqVewwIM0k7KDiCuYWdcA9gVKG0=; b=TTVgsA3G3puZVr9Fucbycq56sRmqvXBiqnWyBcoZp2GbkgGoBMNmMlZp5XXgjBc/SmjwyN Bt81LN6FiQ50V59sowPWmVT+CEgpqNQTq19QCoSGhlFKt/426/ef0eu5tFM+2AkJzmQzxZ noOy7uul2Vrf4UdQ66jU12+NXEYT1ug= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1692185385; a=rsa-sha256; cv=none; b=h4Qm3DmHnCbX2kf7DoQWITttbc1y2ZS4nV4mXmBrsAoIDS2y3Z6QhLZfggn175i7pItRiU 1F4DnY6iGRVAvz+Qk5iPuZJcGqwkWYdWIbQywLvKKiHiNRac7j797rgW4FXUch6ChkiCOT ctoNHvY9I6dz++hGU1vsP39C/Xn98Fk= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=collabora.com header.s=mail header.b=Dt8B2jZb; spf=pass (imf07.hostedemail.com: domain of usama.anjum@collabora.com designates 46.235.227.172 as permitted sender) smtp.mailfrom=usama.anjum@collabora.com; dmarc=pass (policy=quarantine) header.from=collabora.com Received: from [192.168.100.7] (unknown [59.103.216.185]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: usama.anjum) by madras.collabora.co.uk (Postfix) with ESMTPSA id 6B23A66071DF; Wed, 16 Aug 2023 12:29:38 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1692185383; bh=jzdDeX6pUFEUXGNfKX/EwXm6M3rdWUmKoZ0lN9Hznw4=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=Dt8B2jZbp7t6JaXUWr+dIqQM9RjQq2p/RnIdZ7kiF6zOcLSro8jgoV7XUdcMc1Oit LRpKHs3AGqiYDS0sD2De3J020Bpt9SOeJ2KYtIfKLsSTQXfXh1eXWSvgux/FypoVoh uDT5bj7M1rdgnPp92pQpljqC4mx10HCV9jLjzPJdSMX1nAm1QP6LaPa580+5aH2QQ6 KGRBk0B8KPf6RRK4DvtGuBN+VnROAGEAed2E/cqkkHdbn94+1AzLpTkw4RZqCi43IZ 1+wfOIvDjh92S1UnnqihPgYK7/K2CaMMdJbKyGKV663ah8AkBHAKERhHuxY1wYbkxt kUXWM+tOZCd7w== Message-ID: Date: Wed, 16 Aug 2023 16:29:34 +0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.1 Cc: Muhammad Usama Anjum , Peter Xu , Andrew Morton , =?UTF-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= , Andrei Vagin , Paul Gofman , Alexander Viro , Shuah Khan , Christian Brauner , Yang Shi , Vlastimil Babka , "Liam R . Howlett" , Yun Zhou , Suren Baghdasaryan , Alex Sierra , Matthew Wilcox , Pasha Tatashin , Axel Rasmussen , "Gustavo A . R . Silva" , Dan Williams , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, Greg KH , kernel@collabora.com, Cyrill Gorcunov , Mike Rapoport , Nadav Amit , David Hildenbrand Subject: Re: [PATCH v31 2/6] fs/proc/task_mmu: Implement IOCTL to get and optionally clear info about PTEs Content-Language: en-US To: =?UTF-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= References: <20230816103814.1522393-1-usama.anjum@collabora.com> <20230816103814.1522393-3-usama.anjum@collabora.com> From: Muhammad Usama Anjum In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 6129140007 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: nfaroc7ig41h5i49c9tifcwfttnn3jde X-HE-Tag: 1692185385-281793 X-HE-Meta: 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 FfV0mg2t 7J4fsNLAhbbId1og0tuvv3h+KJd884ZJSnasXg0w/46vvXHzI4ZdgY9nZ0cM7zcl8j9AGEjggfVuxhQUzodNjzd5aja9DSK6WLl5PXJFKwwkKcfGrQ02rPEGCLengCC8nuA1b1qo3SUJcS23V8oRIpeA0NL11vkypZ5U42XOJWbbjqoOv0ScOyMMdyzDIKpgrUc6ITnuDXjTLSlMxipyX8YRuRFVaqc3xLC9vQ7AQEG1P1rD5M6aVxqmoLhcr1b1gpaD3 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 8/16/23 4:17 PM, Michał Mirosław wrote: > On Wed, Aug 16, 2023 at 03:38:10PM +0500, Muhammad Usama Anjum wrote: >> The PAGEMAP_SCAN IOCTL on the pagemap file can be used to get or optionally >> clear the info about page table entries. > [...] >> --- a/fs/proc/task_mmu.c >> +++ b/fs/proc/task_mmu.c > [...] >> +static long do_pagemap_scan(struct mm_struct *mm, unsigned long uarg) >> +{ > [...] >> + for (walk_start = p.arg.start; walk_start < p.arg.end; >> + walk_start = p.arg.walk_end) { > [...] >> + /* The walk_end isn't set when ret is zero */ >> + if (!p.arg.walk_end) >> + p.arg.walk_end = p.arg.end; > > This is now redundant with the `if` after the loop. [1] > >> + if (ret != -ENOSPC) >> + break; >> + >> + if (p.arg.vec_len == 0 || p.found_pages == p.arg.max_pages) >> + break; >> + } >> + >> + /* ENOSPC signifies early stop (buffer full) from the walk. */ >> + if (!ret || ret == -ENOSPC) >> + ret = n_ranges_out; >> + >> + if (!p.arg.walk_end) >> + p.arg.walk_end = p.arg.end; > > [1] The one above. Thank you for noting it down. Let me remove it. > > Best Regards > Michał Mirosław -- BR, Muhammad Usama Anjum