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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8A696CA1013 for ; Sat, 6 Sep 2025 00:10:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=90lcV3pTdhO6gX6pQoYlhvAqHg4jcw7Qz2AzOMDouFU=; b=kHTXb7rBwbHIx38X8/Hs0V9hoK axcOi4smX5OW2TBx6T69EJs1h7dGD2x0J9BXSROWnMmjcG1uO9Dc6YncfN58bXNc2QDhN1zH89Suh QPm70qijSerJIOSQETi/g10cG/T3uBkTwpfT5pBwPJdz42lM8N+IXJTk+kNL+AkNWZOHH5rT+67oy o0PI9PJ42W9CSyOQuc5ia6zDaDjkl2eKmnv4graqQAAt2EpObbdwH+cB6z+Jrtk/D6UwifAg6teE2 lcym6OTJDGwtyVjYSh0lYVf8iUO2bm5lDRjajq6EcYaW0LUKXzK+EIuLsAEyVBI4fea2Lf0RVnTjR bnh3e7pw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uugVF-00000005Qz0-337T; Sat, 06 Sep 2025 00:10:01 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uuZAE-000000033hK-0CQF for linux-arm-kernel@lists.infradead.org; Fri, 05 Sep 2025 16:19:51 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BA7DF152B; Fri, 5 Sep 2025 09:19:38 -0700 (PDT) Received: from e133380.arm.com (e133380.arm.com [10.1.197.68]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 654D73F63F; Fri, 5 Sep 2025 09:19:41 -0700 (PDT) Date: Fri, 5 Sep 2025 17:19:34 +0100 From: Dave Martin To: James Morse Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, D Scott Phillips OS , carl@os.amperecomputing.com, lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, baolin.wang@linux.alibaba.com, Jamie Iles , Xin Hao , peternewman@google.com, dfustini@baylibre.com, amitsinght@marvell.com, David Hildenbrand , Rex Nie , Koba Ko , Shanker Donthineni , fenghuay@nvidia.com, baisheng.gao@unisoc.com, Jonathan Cameron , Rob Herring , Rohit Mathew , Rafael Wysocki , Len Brown , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Krzysztof Kozlowski , Conor Dooley , Catalin Marinas , Will Deacon , Greg Kroah-Hartman , Danilo Krummrich Subject: Re: [PATCH 02/33] drivers: base: cacheinfo: Add helper to find the cache size from cpu+level Message-ID: References: <20250822153048.2287-1-james.morse@arm.com> <20250822153048.2287-3-james.morse@arm.com> <2ac66605-ee6a-495b-a0fb-910926abd8b0@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2ac66605-ee6a-495b-a0fb-910926abd8b0@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250905_091950_129750_411B77EB X-CRM114-Status: GOOD ( 22.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On Wed, Aug 27, 2025 at 06:11:43PM +0100, James Morse wrote: > Hi Dave, > > On 27/08/2025 11:46, Dave Martin wrote: > > Hi, > > > > On Fri, Aug 22, 2025 at 03:29:43PM +0000, James Morse wrote: > >> MPAM needs to know the size of a cache associated with a particular CPU. > >> The DT/ACPI agnostic way of doing this is to ask cacheinfo. > >> > >> Add a helper to do this. > > >> diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h [...] > >> +static inline unsigned int get_cpu_cacheinfo_size(int cpu, int level) > >> +{ > >> + struct cacheinfo *ci = get_cpu_cacheinfo_level(cpu, level); > >> + > >> + return ci ? ci->size : 0; > >> +} > >> + > > > > Orphaned function? > > > > Can fs/resctrl/rdtgroup.c:rdtgroup_cbm_to_size() be ported to use this? > > If so, this wouldn't just be dead code in this series. > > Ah - I thought the MPAM driver was pulling this value in, but its the resctrl glue code. > I was trying to reduce the number of trees this touches - its probably best to kick this > into the next series that adds the resctrl code as its pretty trivial. > > > Thanks, > > James > Fair enough. Cheers ---Dave