From patchwork Tue Oct 24 09:03:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhao Liu X-Patchwork-Id: 1854237 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=eB1lgZ1W; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4SF5WG6NFQz23k5 for ; Tue, 24 Oct 2023 19:55:54 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qvDBH-0003NF-La; Tue, 24 Oct 2023 04:54:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qvDAw-0002p3-UL for qemu-devel@nongnu.org; Tue, 24 Oct 2023 04:54:12 -0400 Received: from mgamail.intel.com ([134.134.136.126]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qvDAt-0006Q6-6Y for qemu-devel@nongnu.org; Tue, 24 Oct 2023 04:54:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698137647; x=1729673647; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=7WFJedNLWzB+pwTLUI8IYFyCdnkJ0teulhLYoRGpexs=; b=eB1lgZ1WOB+hNdRgkojuu1GOC7jWi0HaBz9SVUPzLXbJSxfGws1R26aX YeLzTg//W6z7C/1ZP4554K9ECt+mMw9eowf++GShYqljK9ufhvsK4S614 9aLg1KvK+PJqLOG3PTtVvvVYJW2Y9edEK2kB0fHuWK3KrQnRxXY1eQLcB tfnxUbW5l6RsYFF+wp0Z9IEpjTVE6UKOtLWTJ7d1pZeUl/vJaNIhbWfqF 28ZJeHoPpf/dzzqKesTGElK6d61w+99zXFlLfWdTIsZggb0koEAwT8w3C ynBCKE91hmwNLDxN39QDmQ7KmwP5/rWQYDqWGIPMYg7Gd5p+jXhtlCx09 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10872"; a="372077467" X-IronPort-AV: E=Sophos;i="6.03,247,1694761200"; d="scan'208";a="372077467" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2023 01:54:06 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10872"; a="793418404" X-IronPort-AV: E=Sophos;i="6.03,247,1694761200"; d="scan'208";a="793418404" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.36]) by orsmga001.jf.intel.com with ESMTP; 24 Oct 2023 01:54:02 -0700 From: Zhao Liu To: Eduardo Habkost , Marcel Apfelbaum , =?utf-8?q?Philippe_Mathieu-D?= =?utf-8?q?aud=C3=A9?= , Yanan Wang , "Michael S . Tsirkin" , Richard Henderson , Paolo Bonzini , Marcelo Tosatti Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, Zhenyu Wang , Xiaoyao Li , Babu Moger , Yongwei Ma , Zhao Liu Subject: [PATCH v5 19/20] i386: Use offsets get NumSharingCache for CPUID[0x8000001D].EAX[bits 25:14] Date: Tue, 24 Oct 2023 17:03:22 +0800 Message-Id: <20231024090323.1859210-20-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231024090323.1859210-1-zhao1.liu@linux.intel.com> References: <20231024090323.1859210-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Received-SPF: none client-ip=134.134.136.126; envelope-from=zhao1.liu@linux.intel.com; helo=mgamail.intel.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Zhao Liu The commit 8f4202fb1080 ("i386: Populate AMD Processor Cache Information for cpuid 0x8000001D") adds the cache topology for AMD CPU by encoding the number of sharing threads directly. From AMD's APM, NumSharingCache (CPUID[0x8000001D].EAX[bits 25:14]) means [1]: The number of logical processors sharing this cache is the value of this field incremented by 1. To determine which logical processors are sharing a cache, determine a Share Id for each processor as follows: ShareId = LocalApicId >> log2(NumSharingCache+1) Logical processors with the same ShareId then share a cache. If NumSharingCache+1 is not a power of two, round it up to the next power of two. From the description above, the calculation of this field should be same as CPUID[4].EAX[bits 25:14] for Intel CPUs. So also use the offsets of APIC ID to calculate this field. [1]: APM, vol.3, appendix.E.4.15 Function 8000_001Dh--Cache Topology Information Signed-off-by: Zhao Liu Reviewed-by: Babu Moger Tested-by: Babu Moger Tested-by: Yongwei Ma Acked-by: Michael S. Tsirkin --- Changes since v3: * Rewrite the subject. (Babu) * Delete the original "comment/help" expression, as this behavior is confirmed for AMD CPUs. (Babu) * Rename "num_apic_ids" (v3) to "num_sharing_cache" to match spec definition. (Babu) Changes since v1: * Rename "l3_threads" to "num_apic_ids" in encode_cache_cpuid8000001d(). (Yanan) * Add the description of the original commit and add Cc. --- target/i386/cpu.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 90393396a0a4..226c5be6ea95 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -483,7 +483,7 @@ static void encode_cache_cpuid8000001d(CPUCacheInfo *cache, uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx) { - uint32_t l3_threads; + uint32_t num_sharing_cache; assert(cache->size == cache->line_size * cache->associativity * cache->partitions * cache->sets); @@ -492,13 +492,11 @@ static void encode_cache_cpuid8000001d(CPUCacheInfo *cache, /* L3 is shared among multiple cores */ if (cache->level == 3) { - l3_threads = topo_info->modules_per_die * - topo_info->cores_per_module * - topo_info->threads_per_core; - *eax |= (l3_threads - 1) << 14; + num_sharing_cache = 1 << apicid_die_offset(topo_info); } else { - *eax |= ((topo_info->threads_per_core - 1) << 14); + num_sharing_cache = 1 << apicid_core_offset(topo_info); } + *eax |= (num_sharing_cache - 1) << 14; assert(cache->line_size > 0); assert(cache->partitions > 0);