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 287BBCCA476 for ; Tue, 7 Oct 2025 11:11:29 +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=+dA868JnAHP3q2CSQEnaSqNKQJhKRobjZEEDKC4ctiE=; b=4tmzYoThfl5dcmr/GVxJ/FepWB NqXhXPKhmdhXQDYTKjgepTp9MDfp/RI2q0xe2T7txqdNrFAsxOZLw5YrtiJPaEod/++120u3mNw9B wMaQSidlyvUDxiURtlOH8/9qUVV2cqjD6gubYZtq+k5zyMDRe+91ObcgOcC0hTx47IslGWJX1gUYu zAmP6Mtq/1GxGeeEMRflUdHD/tEFrEyE9dJjzxXPv6Ox2Jwr/wZ6NR96flyn0dZ/8z9/uukDQLTy5 Cmv04y7vA4Glkd0nQYiHbsCFL3rgKrZMPbmTRocEsY/fIoDdvoOuH9W9Uuz0u07On/gEFMrynK7cS +fZL5NWw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1v65bF-00000001qTA-1ztv; Tue, 07 Oct 2025 11:11:21 +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 1v65bC-00000001qSo-0BBt for linux-arm-kernel@lists.infradead.org; Tue, 07 Oct 2025 11:11:19 +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 265031424; Tue, 7 Oct 2025 04:11:08 -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 E0BB73F66E; Tue, 7 Oct 2025 04:11:10 -0700 (PDT) Message-ID: <4aec304d-4a89-4957-ac72-148db39f6117@arm.com> Date: Tue, 7 Oct 2025 12:11:09 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 20/29] arm_mpam: Allow configuration to be applied and restored during cpu online To: Jonathan Cameron Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@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 , Dave Martin , Koba Ko , Shanker Donthineni , fenghuay@nvidia.com, baisheng.gao@unisoc.com, 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> <20250910204309.20751-21-james.morse@arm.com> <20250912132229.000044c7@huawei.com> Content-Language: en-GB From: James Morse In-Reply-To: <20250912132229.000044c7@huawei.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-20251007_041118_219497_1F8FDC43 X-CRM114-Status: GOOD ( 20.86 ) 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 Jonathan, On 12/09/2025 13:22, Jonathan Cameron wrote: > On Wed, 10 Sep 2025 20:43:00 +0000 > James Morse wrote: > >> When CPUs come online the MSC's original configuration should be restored. >> >> Add struct mpam_config to hold the configuration. This has a bitmap of >> features that were modified. Once the maximum partid is known, allocate >> a configuration array for each component, and reprogram each RIS >> configuration from this. > Trivial comments > Reviewed-by: Jonathan Cameron Thanks! >> +static void mpam_init_reset_cfg(struct mpam_config *reset_cfg) >> +{ >> + memset(reset_cfg, 0, sizeof(*reset_cfg)); > > Might as well do the following and skip the memset. > > *reset_cfg = (struct mpam_config) { > .features = ~0, > .cpbm = ~0, > .mbw_pbm = ~0, > .mbw_max = MPAM... > .reset_cpbm = true, > .reset_mbw_pbm = true, > }; Sure, >> + reset_cfg->features = ~0; >> + reset_cfg->cpbm = ~0; >> + reset_cfg->mbw_pbm = ~0; >> + reset_cfg->mbw_max = MPAMCFG_MBW_MAX_MAX; >> + >> + reset_cfg->reset_cpbm = true; >> + reset_cfg->reset_mbw_pbm = true; >> +} > >> +static int mpam_allocate_config(void) >> +{ >> + int err = 0; > > Always set before use. Maybe push down so it is in tighter scope and > can declare and initialize to final value in one line. Sure, >> + struct mpam_class *class; >> + struct mpam_component *comp; >> + >> + lockdep_assert_held(&mpam_list_lock); >> + >> + list_for_each_entry(class, &mpam_classes, classes_list) { >> + list_for_each_entry(comp, &class->components, class_list) { >> + err = __allocate_component_cfg(comp); >> + if (err) >> + return err; >> + } >> + } >> + >> + return 0; >> +} > > >> diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h >> index b69fa9199cb4..17570d9aae9b 100644 >> --- a/drivers/resctrl/mpam_internal.h >> +++ b/drivers/resctrl/mpam_internal.h >> @@ -169,11 +169,7 @@ struct mpam_props { >> u16 num_mbwu_mon; >> }; >> >> -static inline bool mpam_has_feature(enum mpam_device_features feat, >> - struct mpam_props *props) >> -{ >> - return (1 << feat) & props->features; >> -} >> +#define mpam_has_feature(_feat, x) ((1 << (_feat)) & (x)->features) > > If this is worth doing push it back to original introduction. > I'm not sure it is necessary. It's the change in this patch that makes it necessary, maybe_update_config() goes calling mpam_has_feature() on a configuration instead of a class/msc/ris props structure. I could have made that a separate helper to get the type right - but making it a macro was simpler. I'll push it back earlier. Thanks, James