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 5672834BA37; Mon, 6 Oct 2025 16:00:56 +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=1759766457; cv=none; b=GBC2HEFeFA3cDrLEnA9HE+8r7wvVvzH0eGUk9XzYrOPLITdCrPu56USn+h+7RCrOWTgRDjNwx7b8j+92EX472dsJLNXL3j11hPV9PAsiYvfc58ZGs0r9LsBb5emlVALIjRhACEjsY9aoS8i0ItnlHpc7ZVlBPE60MA+fhrZpkrQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759766457; c=relaxed/simple; bh=MdYKCQfYRR7YTGxzbHK4Rhuvd0IXNb6NkVSB/PXXHa4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qpuTxk8EhJ8KR0IXSSWWecFw7/wl6eoYfIJKfhlOOAVKSkpd3Q9rgflKSvtRHu9aJJxaMyCW3CijDOQ5dM9//jC8wiopsqnjq5eyfe3b6GYxwfwp8T7XVCQWT9NpW/DDkQXVSjj0SqrB2PekNB24tD8X9DbfsnsCCj1ERQ22AXI= 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 CDEA11516; Mon, 6 Oct 2025 09:00:47 -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 BDB993F738; Mon, 6 Oct 2025 09:00:50 -0700 (PDT) Message-ID: Date: Mon, 6 Oct 2025 17:00:49 +0100 Precedence: bulk X-Mailing-List: linux-kernel@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> <842edca0-11c7-43ac-ba4b-ab40678034e2@arm.com> Content-Language: en-GB From: James Morse In-Reply-To: <842edca0-11c7-43ac-ba4b-ab40678034e2@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Ben, On 12/09/2025 16:08, Ben Horgan wrote: > On 9/11/25 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 >>> + >>> +static void gen_msmon_ctl_flt_vals(struct mon_read *m, u32 *ctl_val, >>> + u32 *flt_val) >>> +{ >>> + struct mon_cfg *ctx = m->ctx; >>> + >>> + /* >>> + * For CSU counters its implementation-defined what happens when not >>> + * filtering by partid. >>> + */ >>> + *ctl_val |= MSMON_CFG_x_CTL_MATCH_PARTID; >>> + >>> + *flt_val = FIELD_PREP(MSMON_CFG_x_FLT_PARTID, ctx->partid); >>> + if (m->ctx->match_pmg) { >>> + *ctl_val |= MSMON_CFG_x_CTL_MATCH_PMG; >>> + *flt_val |= FIELD_PREP(MSMON_CFG_x_FLT_PMG, ctx->pmg); >>> + } >>> + >>> + switch (m->type) { >>> + case mpam_feat_msmon_csu: >>> + *ctl_val = MSMON_CFG_CSU_CTL_TYPE_CSU; >>> + >>> + if (mpam_has_feature(mpam_feat_msmon_csu_xcl, &m->ris->props)) >>> + *flt_val |= FIELD_PREP(MSMON_CFG_CSU_FLT_XCL, >>> + ctx->csu_exclude_clean); >>> + >>> + break; >>> + case mpam_feat_msmon_mbwu: >>> + *ctl_val = MSMON_CFG_MBWU_CTL_TYPE_MBWU; > > As you mentioned offline, this zeroes the other bits in *ctl_val. Yes - a bug introduced during a late night, I've fixed this up. Thanks, James