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=-7.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED 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 0261CC004C9 for ; Sun, 5 May 2019 07:11:14 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id CA2602087F for ; Sun, 5 May 2019 07:11:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="GUSi+IzG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CA2602087F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:To:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=63880QERXIZw1o4K/9WdJW5YJd0rSVxPJrAR2/UScrw=; b=GUSi+IzGm/gzAN 55aR8XG/1N5GLyxPfBlnCOTbGD6BQd+EAHbWWGHlWgXM+31ceObzhmAuijaT3ti0cshRzjM8K7Tnl OxTJN++jH24vVq8OoHNjQwoBq00Oe6ybiHVYWcC7b7W08P4Ci2DJWAh7I06Px7QK9A2DWzA8O6G60 z2Y4/or626EMdSYMI1nE8GSxpbNwOvO3m6DtIUXo2/tOjsnAITDlLyi93h73USP+AXnRnPwYXEw0I dWc2PTKnhM66DbcU7H2cx+WenFIf7EzoCB9s7ythxFZexWkmee7h27ZVOzhwI1pqNit3qACiYQZ2u B4Rs6EEXL56F0H63n0sA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hNBIc-00068E-Uu; Sun, 05 May 2019 07:11:02 +0000 Received: from szxga07-in.huawei.com ([45.249.212.35] helo=huawei.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hNBIZ-000673-80 for linux-arm-kernel@lists.infradead.org; Sun, 05 May 2019 07:11:00 +0000 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 0CDC92711EA03533A31B; Sun, 5 May 2019 15:10:42 +0800 (CST) Received: from [127.0.0.1] (10.177.19.180) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.439.0; Sun, 5 May 2019 15:10:33 +0800 Subject: Re: [PATCH v3 2/5] ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens To: Jeremy Linton , References: <20190503232407.37195-1-jeremy.linton@arm.com> <20190503232407.37195-3-jeremy.linton@arm.com> From: Kefeng Wang Message-ID: Date: Sun, 5 May 2019 15:09:01 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.3.1 MIME-Version: 1.0 In-Reply-To: <20190503232407.37195-3-jeremy.linton@arm.com> Content-Language: en-US X-Originating-IP: [10.177.19.180] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190505_001059_531948_C21C9CC4 X-CRM114-Status: GOOD ( 16.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, lorenzo.pieralisi@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, rjw@rjwysocki.net, linuxarm@huawei.com, linux-acpi@vger.kernel.org, sudeep.holla@arm.com, lenb@kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2019/5/4 7:24, Jeremy Linton wrote: > ACPI 6.3 adds a flag to indicate that child nodes are all > identical cores. This is useful to authoritatively determine > if a set of (possibly offline) cores are identical or not. > > Since the flag doesn't give us a unique id we can generate > one and use it to create bitmaps of sibling nodes, or simply > in a loop to determine if a subset of cores are identical. > > Signed-off-by: Jeremy Linton > --- > drivers/acpi/pptt.c | 26 ++++++++++++++++++++++++++ > include/linux/acpi.h | 5 +++++ > 2 files changed, 31 insertions(+) > > diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c > index 83a026765faa..1865515297ca 100644 > --- a/drivers/acpi/pptt.c > +++ b/drivers/acpi/pptt.c > @@ -660,3 +660,29 @@ int find_acpi_cpu_topology_package(unsigned int cpu) > return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, > ACPI_PPTT_PHYSICAL_PACKAGE); > } > + > +/** > + * find_acpi_cpu_topology_hetero_id() - Get a core architecture tag > + * @cpu: Kernel logical CPU number > + * > + * Determine a unique heterogeneous tag for the given CPU. CPUs with the same > + * implementation should have matching tags. > + * > + * The returned tag can be used to group peers with identical implementation. > + * > + * The search terminates when a level is found with the identical implementation > + * flag set or we reach a root node. > + * > + * Due to limitations in the PPTT data structure, there may be rare situations > + * where two cores in a heterogeneous machine may be identical, but won't have > + * the same tag. > + * > + * Return: -ENOENT if the PPTT doesn't exist, or the CPU cannot be found. > + * Otherwise returns a value which represents a group of identical cores > + * similar to this CPU. > + */ > +int find_acpi_cpu_topology_hetero_id(unsigned int cpu) > +{ > + return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, > + ACPI_PPTT_ACPI_IDENTICAL); > +} > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index d5dcebd7aad3..1444fb042898 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -1309,6 +1309,7 @@ static inline int lpit_read_residency_count_address(u64 *address) > #ifdef CONFIG_ACPI_PPTT > int find_acpi_cpu_topology(unsigned int cpu, int level); > int find_acpi_cpu_topology_package(unsigned int cpu); > +int find_acpi_cpu_topology_hetero_id(unsigned int cpu); > int find_acpi_cpu_cache_topology(unsigned int cpu, int level); > #else > static inline int find_acpi_cpu_topology(unsigned int cpu, int level) > @@ -1319,6 +1320,10 @@ static inline int find_acpi_cpu_topology_package(unsigned int cpu) > { > return -EINVAL; > } static inline int find_acpi_cpu_topology_hetero_id(unsigned int cpu) > +static int find_acpi_cpu_topology_hetero_id(unsigned int cpu) > +{ > + return -EINVAL; > +} > static inline int find_acpi_cpu_cache_topology(unsigned int cpu, int level) > { > return -EINVAL; _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel