From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2DC0A2D94BB; Mon, 6 Oct 2025 16:00:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759766409; cv=none; b=nxNP2Uj+xoUWnc6gCOpcl0m+qJjvDM11U/1ZWyYYsGPVkflxoHhwhgqiTo+KmV82E7OFPaiwrXyff8YOzd993eHsrcysg6+Jf8Ws7bGbmNDAkl+X4loK6/9kxc42YR5+Ez9P8bD3Sk6T72rg/QlKpBixCjoqYLHnK+05H0/+v5s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759766409; c=relaxed/simple; bh=017mx55a33CQXrt4HRZdEp+wgp9KSSCismm4YwmfCns=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Y5qHGgp9Cdj6nOtVGbTz8UU/I2/pgXRHglY8YGyanlKST72N/dP5D6ZVM8or6ey6ZK2vUvK+gHX0mPx/oruKK9UC9nwkJWz8++wNJZVxY5gMPK4RTrFEKEls+Ll1QP/vaXZ+CIpLyK0dZYU3u5WyFPRI8/A3Tn2NtIi7n5RhKzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 422A21515; Mon, 6 Oct 2025 08:59:56 -0700 (PDT) Received: from [10.1.197.69] (eglon.cambridge.arm.com [10.1.197.69]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 577313F738; Mon, 6 Oct 2025 08:59:58 -0700 (PDT) Message-ID: <8ecfb414-dc3d-4e66-90cf-427b22d4a949@arm.com> Date: Mon, 6 Oct 2025 16:59:56 +0100 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 23/29] arm_mpam: Add mpam_msmon_read() to read monitor value To: Ben Horgan , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org Cc: 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 , Dave Martin , 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 , Catalin Marinas , Will Deacon , Greg Kroah-Hartman , Danilo Krummrich References: <20250910204309.20751-1-james.morse@arm.com> <20250910204309.20751-24-james.morse@arm.com> <1344b395-66aa-4714-b1fc-9c970c0fd0bf@arm.com> Content-Language: en-GB From: James Morse In-Reply-To: <1344b395-66aa-4714-b1fc-9c970c0fd0bf@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Ben, On 11/09/2025 16:46, Ben Horgan wrote: > On 9/10/25 21:43, James Morse wrote: >> Reading a monitor involves configuring what you want to monitor, and >> reading the value. Components made up of multiple MSC may need values >> from each MSC. MSCs may take time to configure, returning 'not ready'. >> The maximum 'not ready' time should have been provided by firmware. >> >> Add mpam_msmon_read() to hide all this. If (one of) the MSC returns >> not ready, then wait the full timeout value before trying again. >> diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c >> index cf190f896de1..1543c33c5d6a 100644 >> --- a/drivers/resctrl/mpam_devices.c >> +++ b/drivers/resctrl/mpam_devices.c >> @@ -898,6 +898,232 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc) >> +static int _msmon_read(struct mpam_component *comp, struct mon_read *arg) >> +{ >> + int err, idx; >> + struct mpam_msc *msc; >> + struct mpam_vmsc *vmsc; >> + struct mpam_msc_ris *ris; >> + >> + idx = srcu_read_lock(&mpam_srcu); >> + list_for_each_entry_rcu(vmsc, &comp->vmsc, comp_list) { > > This can be list_for_each_entry_srcu(). (I thought I'd already commented > but turns out that was on another patch.) > >> + msc = vmsc->msc; >> + >> + list_for_each_entry_rcu(ris, &vmsc->ris, vmsc_list) { > > Also here. Yup - thanks I missed these. Fixed. I bet I went cross-eyed between here and mpam_apply_config() as they are structurally similar. Thanks, James