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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F829C433EF for ; Thu, 21 Oct 2021 12:03:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9B7E56120C for ; Thu, 21 Oct 2021 12:03:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 9B7E56120C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 23E9B900004; Thu, 21 Oct 2021 08:03:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1EDC4900002; Thu, 21 Oct 2021 08:03:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 104B5900004; Thu, 21 Oct 2021 08:03:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0151.hostedemail.com [216.40.44.151]) by kanga.kvack.org (Postfix) with ESMTP id 03750900002 for ; Thu, 21 Oct 2021 08:03:57 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id BCA1818088DFF for ; Thu, 21 Oct 2021 12:03:56 +0000 (UTC) X-FDA: 78720310872.05.51652BB Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf06.hostedemail.com (Postfix) with ESMTP id 7D79A801A89F for ; Thu, 21 Oct 2021 12:03:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=hp2dNCx95JcsISYZ6Sb5wN1lWRmuob1doeRvoZZX2tA=; b=X96b/OUUwWMCB8kedTeH33H346 lPb6No4F1NGnCRNH86Cgi/Y0r5FxcGMpVYedGOHrUlCUpOxsKOg77CEdqOd7eW5Zc4sbQBeQ86Nzw vEuh0yYLTOBbyojRruFQh9xIfCn5huHcsmmAzJokZZ5jBGUP8PB4ZRkqHspZRL+oRIJc4xStec0G8 Bi7/i6Y2M2wcDztjZP5x+y6wVMQI75lxEZm5CFVDhUk6FHGv0cVz80UEjqTtRhZZK8p3BY8rRf72a yMBGxegEPSuYjtdpWrm1H9GWEHGkHVLfSJ51cAAoToGs+B+wmriX3oaHS2KTEvSr2iJ0+DTmcsKwI aMwybIsQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mdWlG-00DFKr-IN; Thu, 21 Oct 2021 12:02:08 +0000 Date: Thu, 21 Oct 2021 13:01:30 +0100 From: Matthew Wilcox To: Christoph Hellwig Cc: Manjong Lee , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, seunghwan.hyun@samsung.com, sookwan7.kim@samsung.com, nanich.lee@samsung.com, yt0928.kim@samsung.com, junho89.kim@samsung.com, jisoo2146.oh@samsung.com Subject: Re: [PATCH 1/1] mm: bdi: Initialize bdi_min_ratio when bdi unregister Message-ID: References: <20211021161942.5983-1-mj0123.lee@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 7D79A801A89F X-Stat-Signature: dm3gsbucxw51wt5uo5kof5x93xjarhzo Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b="X96b/OUU"; spf=none (imf06.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-HE-Tag: 1634817834-634010 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 Thu, Oct 21, 2021 at 04:16:52AM -0700, Christoph Hellwig wrote: > On Fri, Oct 22, 2021 at 01:19:43AM +0900, Manjong Lee wrote: > > Because when sdcard is removed, bdi_min_ratio value will remain. > > Currently, the only way to reset bdi_ min_ratio is to reboot. > > But bdis that are unregistered are never re-registered. What is > the problem you're trying to solve? The global bdi_min_ratio needs to be adjusted. See bdi_set_min_ratio() in mm/page-writeback.c.