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Mon, 18 Dec 2023 03:29:57 +0000 (UTC) X-FDA: 81578510034.28.82125FF Received: from out30-110.freemail.mail.aliyun.com (out30-110.freemail.mail.aliyun.com [115.124.30.110]) by imf10.hostedemail.com (Postfix) with ESMTP id 2D183C0007 for ; Mon, 18 Dec 2023 03:29:53 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf10.hostedemail.com: domain of jefflexu@linux.alibaba.com designates 115.124.30.110 as permitted sender) smtp.mailfrom=jefflexu@linux.alibaba.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1702870196; 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; bh=F7gqXQloaL0taZNL59uwn6vMgd462zTGy0af515z92I=; b=lL0r01ZFsVvjrGbN3pw48A1o15pP2JisIJEljWJpw4YkPhssDwD5eNY8fMsG0FxJT0rM9V /muxfZVm5bit+08Dv9+fjyOk4OtAtqy9QDYf4BHw57SB3oUi5dLSN3Abd5hg/HjRwsurJy 4kdoPSWuKRf0ID0tIKcfuyxRBPIeRII= ARC-Authentication-Results: i=1; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 2D183C0007 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: kpc7r63wqd3gk3mbxoczi9zns68n17ot X-HE-Tag: 1702870193-358593 X-HE-Meta: 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 tfcf7QZy VQbUnxyDs6XEKejynMajvAWDHdhBCeHkGgy4Sa/PlvP/eOYZwT4RAogyN+rSdSFnGPpKKzQatz4u2x28RIv3riIAvb+akgfAy2HqZm9bjcmK6DO3zHhVLpohWJKVUld3WpWaJTmCX/2fDuSPER4FEMZBS6w44BhX7hagFqdX0lny/KYx3VQ+fTH4ljNUitUWZuEp/VjS6VQW7bV2PBKsIxbjGOVkY08bdaYFpSwtCTv8NrDLjhJkDEft36mITTsv8vhbD 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: List-Subscribe: List-Unsubscribe: +cc fsdevel On 12/18/23 11:16 AM, Jingbo Xu wrote: > bdi->[min|max]_ratio are both part per million. Fix the wrong > arithmetic when setting bdi's min_ratio and max_ratio. > > Fixes: efc3e6ad53ea ("mm: split off __bdi_set_max_ratio() function") > Fixes: 8021fb3232f2 ("mm: split off __bdi_set_min_ratio() function") > Reported-by: Joseph Qi > Signed-off-by: Jingbo Xu > --- > mm/page-writeback.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index ee2fd6a6af40..b393b3281ce9 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -692,7 +692,6 @@ static int __bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ra > > if (min_ratio > 100 * BDI_RATIO_SCALE) > return -EINVAL; > - min_ratio *= BDI_RATIO_SCALE; > > spin_lock_bh(&bdi_lock); > if (min_ratio > bdi->max_ratio) { > @@ -729,7 +728,8 @@ static int __bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ra > ret = -EINVAL; > } else { > bdi->max_ratio = max_ratio; > - bdi->max_prop_frac = (FPROP_FRAC_BASE * max_ratio) / 100; > + bdi->max_prop_frac = div64_u64(FPROP_FRAC_BASE * max_ratio, > + 100UL * BDI_RATIO_SCALE); > } > spin_unlock_bh(&bdi_lock); > -- Thanks, Jingbo