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 X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E074C4338F for ; Wed, 25 Aug 2021 13:56:21 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C34D360F35 for ; Wed, 25 Aug 2021 13:56:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C34D360F35 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.172392.314534 (Exim 4.92) (envelope-from ) id 1mItNx-0000Ok-9K; Wed, 25 Aug 2021 13:56:09 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 172392.314534; Wed, 25 Aug 2021 13:56:09 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mItNx-0000Od-6H; Wed, 25 Aug 2021 13:56:09 +0000 Received: by outflank-mailman (input) for mailman id 172392; Wed, 25 Aug 2021 13:56:07 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mItNv-0000OL-RV for xen-devel@lists.xenproject.org; Wed, 25 Aug 2021 13:56:07 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mItNu-0006SH-Vi; Wed, 25 Aug 2021 13:56:06 +0000 Received: from 54-240-197-238.amazon.com ([54.240.197.238] helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1mItNu-0006Pk-Pw; Wed, 25 Aug 2021 13:56:06 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject; bh=n/AU32IRlgscmQqHqg2VsAxf/1pZSghjHTm4YaO3jTE=; b=jQMNIl+7X3grwBQkLTcB6aPo0o PonqcyXFuZfFwKvH1CNC854wA7Mbh3X1uQbKovoxoJ7rxjltjVp4vz7UIDZb6p8moRGjRcCNn97GU se9DKEm5DrJlfKOHqPg5X9m/xJMr+NdPhQDvCUv3/B6OMgdw6lFWIHDjHH6HFAeWlaCo=; Subject: Re: [XEN RFC PATCH 24/40] xen/arm: introduce a helper to parse device tree NUMA distance map To: Wei Chen , xen-devel@lists.xenproject.org, sstabellini@kernel.org Cc: Bertrand.Marquis@arm.com, Jan Beulich References: <20210811102423.28908-1-wei.chen@arm.com> <20210811102423.28908-25-wei.chen@arm.com> From: Julien Grall Message-ID: Date: Wed, 25 Aug 2021 14:56:04 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20210811102423.28908-25-wei.chen@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Hi Wei, On 11/08/2021 11:24, Wei Chen wrote: > A NUMA aware device tree will provide a "distance-map" node to > describe distance between any two nodes. This patch introduce a s/introduce/introduces/ > new helper to parse this distance map. > > Signed-off-by: Wei Chen > --- > xen/arch/arm/numa_device_tree.c | 67 +++++++++++++++++++++++++++++++++ > 1 file changed, 67 insertions(+) > > diff --git a/xen/arch/arm/numa_device_tree.c b/xen/arch/arm/numa_device_tree.c > index bbe081dcd1..6e0d1d3d9f 100644 > --- a/xen/arch/arm/numa_device_tree.c > +++ b/xen/arch/arm/numa_device_tree.c > @@ -200,3 +200,70 @@ device_tree_parse_numa_memory_node(const void *fdt, int node, > > return 0; > } > + > +/* Parse NUMA distance map v1 */ > +int __init > +device_tree_parse_numa_distance_map_v1(const void *fdt, int node) > +{ > + const struct fdt_property *prop; > + const __be32 *matrix; > + int entry_count, len, i; entry_count and i should be unsigned. len unfortunately can't because fdt_get_property expects a signed int. > + > + printk(XENLOG_INFO "NUMA: parsing numa-distance-map\n"); > + > + prop = fdt_get_property(fdt, node, "distance-matrix", &len); > + if ( !prop ) > + { > + printk(XENLOG_WARNING > + "NUMA: No distance-matrix property in distance-map\n"); > + > + return -EINVAL; > + } > + > + if ( len % sizeof(uint32_t) != 0 ) > + { > + printk(XENLOG_WARNING > + "distance-matrix in node is not a multiple of u32\n"); > + return -EINVAL; > + } > + > + entry_count = len / sizeof(uint32_t); > + if ( entry_count <= 0 ) I understand that entry_count may be 0. But I can't see how it can be negative as the property len cannot be (even if it is a signed type). So I think this wants to be "== 0". > + { > + printk(XENLOG_WARNING "NUMA: Invalid distance-matrix\n"); > + > + return -EINVAL; > + } > + > + matrix = (const __be32 *)prop->data; > + for ( i = 0; i + 2 < entry_count; i += 3 ) > + { > + uint32_t from, to, distance; > + > + from = dt_read_number(matrix, 1); > + matrix++; You can use dt_next_cell() which will update the pointer for you. > + to = dt_read_number(matrix, 1); > + matrix++; > + distance = dt_read_number(matrix, 1); > + matrix++; > + > + if ( (from == to && distance != NUMA_LOCAL_DISTANCE) || > + (from != to && distance <= NUMA_LOCAL_DISTANCE) ) > + { > + printk(XENLOG_WARNING > + "Invalid nodes' distance from node#%d to node#%d = %d\n", > + from, to, distance); > + return -EINVAL; > + } > + > + printk(XENLOG_INFO "NUMA: distance from node#%d to node#%d = %d\n", > + from, to, distance); > + numa_set_distance(from, to, distance); > + > + /* Set default distance of node B->A same as A->B */ > + if (to > from) > + numa_set_distance(to, from, distance); > + } > + > + return 0; > +} > Cheers, -- Julien Grall