From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B48522E92BC for ; Tue, 13 Jan 2026 15:06:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768316786; cv=none; b=DzC+LSJnqvKqKeA5iKWTHtbGj8uqRWlhUzBtwNyXVu4x7tSrYLEYDWmPjdX6IS/sL341N+UQ/OVvdYdBq6h2eM9/38bIt6OFfZ4yKBrcT6I47DFfgHP62QpV2vwVc8+BFQAAUHJJ6uPTXtwhUuDvW2Np5P48J8iWq8R4mzbPAvk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768316786; c=relaxed/simple; bh=xReIy5MJhHpWl6HB0ZFWLieRi6OMaYiKLaD3+3YmNMQ=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=mLineFEThyBmrdrD9TM9D5e3nRfM69U6jJH5dn2iH8nUlaVxI4IYjpQU1fJiji8A2LzomfJaH29Uj+4IcHGz7iZCmjB11aX2YWSQbQWbcgQoum9pHghqeac/iVrwfD1mPm9XzvvsK3tcp5RvHiaYShdp29rD3ilmrohzsUrUgN0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.224.150]) by frasgout.his.huawei.com (SkyGuard) with ESMTPS id 4drCHh1ktVzJ46F1; Tue, 13 Jan 2026 23:06:08 +0800 (CST) Received: from dubpeml100005.china.huawei.com (unknown [7.214.146.113]) by mail.maildlp.com (Postfix) with ESMTPS id 67A8140539; Tue, 13 Jan 2026 23:06:21 +0800 (CST) Received: from localhost (10.203.177.15) by dubpeml100005.china.huawei.com (7.214.146.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Tue, 13 Jan 2026 15:06:19 +0000 Date: Tue, 13 Jan 2026 15:06:18 +0000 From: Jonathan Cameron To: Ben Horgan CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Zeng Heng Subject: Re: [PATCH v3 27/47] arm_mpam: resctrl: Add support for 'MB' resource Message-ID: <20260113150618.00003829@huawei.com> In-Reply-To: <20260112165914.4086692-28-ben.horgan@arm.com> References: <20260112165914.4086692-1-ben.horgan@arm.com> <20260112165914.4086692-28-ben.horgan@arm.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml100010.china.huawei.com (7.191.174.197) To dubpeml100005.china.huawei.com (7.214.146.113) On Mon, 12 Jan 2026 16:58:54 +0000 Ben Horgan wrote: > From: James Morse > > resctrl supports 'MB', as a percentage throttling of traffic somewhere > after the L3. This is the control that mba_sc uses, so ideally the class > chosen should be as close as possible to the counters used for mba_local. > > MB's percentage control should be backed either with the fixed point > fraction MBW_MAX or bandwidth portion bitmaps. The bandwidth portion > bitmaps is not used as its tricky to pick which bits to use to avoid > contention, and may be possible to expose this as something other than a > percentage in the future. > > CC: Zeng Heng > Co-developed-by: Dave Martin > Signed-off-by: Dave Martin > Signed-off-by: James Morse > > Signed-off-by: Ben Horgan Reviewed-by: Jonathan Cameron