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=-6.9 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 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 40C4FC004C9 for ; Tue, 7 May 2019 18:26:54 +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 17AF6205C9 for ; Tue, 7 May 2019 18:26:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="dDIQyXL4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 17AF6205C9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.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-Type: Content-Transfer-Encoding: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=3wCIF2Bk2O13r9A4qLF7w+EdJTf6nYP7ggW9DrD5WEU=; b=dDIQyXL4rmHATgSxeQLeoeEiz /HFtPaeYJMkPUuZwh7Seu6lqaS0BHk8MvZxhnRpgRjFaAnMKghRa3jsc1TiTp+VlmABHyvLsYP02h bix9aqu0vNGGH2bn9cSLCmQFAFH9+JIbJVj3UYrKTANSQab2bpppzy0FO0zfaOp58rnNg69dCjP+t SOFiJNPO/Igbuf+iaM6qwo5e2fwTUAUGXVBrNfeHU3VkbKRZdAwzbfn2QTJPqU7AnrLBMaCQZhjQx 9Q+vgevnaWt4o+BISek+EQ97dvLs0oX3s8m7iITuTIEJiWuK6nrkuexNsSLsb5oxW0y2nWAbapJdN lXAfCcIeg==; 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 1hO4ng-0004wY-KA; Tue, 07 May 2019 18:26:48 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hO4nV-0004la-RQ for linux-arm-kernel@lists.infradead.org; Tue, 07 May 2019 18:26:39 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E214915AB; Tue, 7 May 2019 11:26:36 -0700 (PDT) Received: from [192.168.100.241] (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B5A013F5AF; Tue, 7 May 2019 11:26:35 -0700 (PDT) Subject: Re: [PATCH v3 2/5] ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens To: Kefeng Wang , linux-arm-kernel@lists.infradead.org References: <20190503232407.37195-1-jeremy.linton@arm.com> <20190503232407.37195-3-jeremy.linton@arm.com> From: Jeremy Linton Message-ID: Date: Tue, 7 May 2019 13:26:28 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190507_112637_892851_BA596CD3 X-CRM114-Status: GOOD ( 17.04 ) 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-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On 5/5/19 2:09 AM, Kefeng Wang wrote: > > 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) Yes, good catch, I just saw that warning. >> +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