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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2521DC00140 for ; Tue, 26 Jul 2022 14:03:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239195AbiGZODy (ORCPT ); Tue, 26 Jul 2022 10:03:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234104AbiGZODw (ORCPT ); Tue, 26 Jul 2022 10:03:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DADB1262F for ; Tue, 26 Jul 2022 07:03:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BCE3D61618 for ; Tue, 26 Jul 2022 14:03:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 954C0C433D6; Tue, 26 Jul 2022 14:03:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1658844231; bh=nuoaHapxy+kdCtIiY/eWKlFYJB/dZW+a0RR33I/yFmA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=fcopf3ICeT8v4NnvPQ9skNVNT4AC6OgccMV3gCJfSaRiQUvlo9sOiLKtu0f4jHjVA I6LGGJKizFbC1H5vWJf9kW5bnkHrfPLCOcYUAd885TjyzTfh1jwQKCFpuSuRqRS05k oOHaYuyxuXXTRzMBBkO9+4CKw0puGfncKZOjzRbYYOZaNCXH38IqSsgVaYpH3FGVkW q0BbKSdAPBgXT78HCnZcl/1qdiUto5BJkQdrDMvPpbUsQdyK66hrRHGyBNfY0Nxibx qk8qo+7WBDZqxA9UeqAd/eXKEEB68RE3fP2lmCBL8GcyZA+J7nWGHXYKgI4FauimF4 eCFQ3SjWp0Mmg== Message-ID: Date: Tue, 26 Jul 2022 16:03:47 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] mm/page_owner.c: allow page_owner with given start_pfn/count Content-Language: en-US To: Kassey Li , Matthew Wilcox Cc: akpm@linux-foundation.org, minchan@kernel.org, iamjoonsoo.kim@lge.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, quic_guptap@quicinc.com References: <20220722150810.27740-1-quic_yingangl@quicinc.com> From: "Vlastimil Babka (SUSE)" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/25/22 10:39, Kassey Li wrote: > hi, Matthew: >     sorry for the delay, I just started to learn how to upstream patch, and > setup my Thunderbird with plain text only. >     you are right, two users will cause problem here. >     the uses case is dump CMA area to understand the page usage in a given > cma pool. 2nd, dump whole memory page owner is very time cost, mostly our > android device has 8G memory now. >     I will research and check again, if you have more idea on this , please > kindly to share. You could try employing lseek() to specify the start pfn, and as for end pfn, the process can just stop reading and close when it has seen enough? > BR > Kassey > > On 7/22/2022 11:38 PM, Matthew Wilcox wrote: >> On Fri, Jul 22, 2022 at 11:08:10PM +0800, Kassey Li wrote: >>> by default, page_owner iterates all page from min_low_pfn to >>> max_pfn, this cost too much time if we want an alternative pfn range. >>> >>> with this patch it allows user to set pfn range to dump the page_onwer. >> >> This is a really bad UI.  If two users try to do different ranges at the >> same time, it'll go wrong.  What use cases are you actually trying to >> solve? >