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 3C11CCA101F for ; Fri, 12 Sep 2025 11:42:34 +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:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TUUlkA71AexTCDSRAb+2plNWEvm5hoJmtzXggAJ0jXw=; b=OuQ3Pymjvo52h7PqIjLyfVyuye Ffn2pe+5vW82Sqlc9C4QYHyOI2q6VLK4+6qD09cXn1PMmOaPDQ40cDcvZgjUM5B78YGZl2sBFP2tG JloWCBVH2ML01sWhOu8o07XNhKl7/pr48288b64E9p6bxsROwRzgacCWTGN0WvbLoC4A7LiccvsQs lg0MVNg63KTxKGnzuk5Wwpi7ToDe2hNY7JBYG5RKMRC8HQWlAh1G/6cI4MoTIV7uvPv8qB7CsRYzg s3p6ByNlK+odqr3d1R478CxGMWyqYYcs5J816zPsChDpzR6ka28PDbRAhhcqmLjTBwcAmqamC4bps T6YskEnQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ux2Ae-00000008wYe-0rqP; Fri, 12 Sep 2025 11:42:28 +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 1ux2Ab-00000008wXc-21RD for linux-arm-kernel@lists.infradead.org; Fri, 12 Sep 2025 11:42:26 +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 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 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250912_044225_572173_8E6DC58F X-CRM114-Status: GOOD ( 18.47 ) 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 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