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 4814441C62; Fri, 12 Sep 2025 11:42:24 +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=1757677347; cv=none; b=Y/Hqk13XmhDMQ4UP/nIQ8ez6nywySYGxGKArysbChPboftM6Iw7vGVX9hRA7owFXu8oSzclg37Yk4i9CAs8fxdotU1CKCZ/ssjZWP4GlyTSx/MxHK/jVYCP5bVKibj27WVS7gXxwPFA1YO0zXTZ3NlEaU1AUG/5ySaki696vENA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757677347; c=relaxed/simple; bh=Nce4M5Uob+uKbWUiwuuOIZjfNSwB8qg0u6HvK4qFifM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=odrBX4JOW2JmBHtbMbbinmGkd3Q8g0ypiVu4xk1rHcqnqYibxDAOFgko3BNPYXQ0XOr7eFlda3twZQ0O6dJmCqZZK+Y33I4CdmJI9TD1FeMVYD6zLwQwXAdT/xwfFSjn8gedVr/szgATz/vGjkZ+OdQlH+pe3YaaJGfLL4CCC8w= 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 41EA516A3; Fri, 12 Sep 2025 04:42:16 -0700 (PDT) Received: from [10.1.196.46] (e134344.arm.com [10.1.196.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 133E53F63F; Fri, 12 Sep 2025 04:42:19 -0700 (PDT) Message-ID: <9fa1b584-130b-45b0-9dba-8e046e643bf0@arm.com> Date: Fri, 12 Sep 2025 12:42:18 +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 17/29] arm_mpam: Extend reset logic to allow devices to be reset any time To: James Morse , 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> <20250910204309.20751-18-james.morse@arm.com> From: Ben Horgan Content-Language: en-US In-Reply-To: <20250910204309.20751-18-james.morse@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi James, On 9/10/25 21:42, James Morse wrote: > cpuhp callbacks aren't the only time the MSC configuration may need to > be reset. Resctrl has an API call to reset a class. > If an MPAM error interrupt arrives it indicates the driver has > misprogrammed an MSC. The safest thing to do is reset all the MSCs > and disable MPAM. > > Add a helper to reset RIS via their class. Call this from mpam_disable(), > which can be scheduled from the error interrupt handler. > > Signed-off-by: James Morse > --- > Changes since v1: > * more complete use of _srcu helpers. > * Use guard macro for srcu. > * Dropped a might_sleep() - something else will bark. > --- > drivers/resctrl/mpam_devices.c | 56 ++++++++++++++++++++++++++++++++-- > 1 file changed, 54 insertions(+), 2 deletions(-) > > diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c > index e7faf453b5d7..a9d3c4b09976 100644 > --- a/drivers/resctrl/mpam_devices.c > +++ b/drivers/resctrl/mpam_devices.c > @@ -842,8 +842,6 @@ static int mpam_reset_ris(void *arg) > u16 partid, partid_max; > struct mpam_msc_ris *ris = arg; > > - mpam_assert_srcu_read_lock_held(); > - Remove where it is introduced. There is already one in mpam_reset_ris_partid() at that time. > if (ris->in_reset_state) > return 0; Reviewed-by: Ben Horgan Thanks, Ben