From nobody Sat May 4 08:40:13 2024 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B3E68C76196 for ; Tue, 28 Mar 2023 11:50:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232949AbjC1LuD (ORCPT ); Tue, 28 Mar 2023 07:50:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232950AbjC1Lt7 (ORCPT ); Tue, 28 Mar 2023 07:49:59 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54DAA8A6E for ; Tue, 28 Mar 2023 04:49:54 -0700 (PDT) Received: from canpemm500009.china.huawei.com (unknown [172.30.72.54]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Pm7FB5VHCz17PdD; Tue, 28 Mar 2023 19:46:38 +0800 (CST) Received: from localhost.localdomain (10.50.163.32) by canpemm500009.china.huawei.com (7.192.105.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Tue, 28 Mar 2023 19:49:52 +0800 From: Yicong Yang To: , , , , , CC: , , Subject: [PATCH v2] cacheinfo: Fix LLC is not exported through sysfs Date: Tue, 28 Mar 2023 19:49:15 +0800 Message-ID: <20230328114915.33340-1-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.50.163.32] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500009.china.huawei.com (7.192.105.203) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Yicong Yang After entering 6.3-rc1 the LLC cacheinfo is not exported on our ACPI based arm64 server. This is because the LLC cacheinfo is partly reset when secondary CPUs boot up. On arm64 the primary cpu will allocate and setup cacheinfo: init_cpu_topology() for_each_possible_cpu() fetch_cache_info() // Allocate cacheinfo and init levels detect_cache_attributes() cache_shared_cpu_map_setup() if (!last_level_cache_is_valid()) // not valid, setup LLC cache_setup_properties() // setup LLC On secondary CPU boot up: detect_cache_attributes() populate_cache_leaves() get_cache_type() // Get cache type from clidr_el1, // for LLC type=3DCACHE_TYPE_NOCACHE cache_shared_cpu_map_setup() if (!last_level_cache_is_valid()) // Valid and won't go to this branch, // leave LLC's type=3DCACHE_TYPE_NOCA= CHE The last_level_cache_is_valid() use cacheinfo->{attributes, fw_token} to test it's valid or not, but populate_cache_leaves() will only reset LLC's type, so we won't try to re-setup LLC's type and leave it CACHE_TYPE_NOCACHE and won't export it through sysfs. This patch tries to fix this by not re-populating the cache leaves if the LLC is valid. Fixes: 5944ce092b97 ("arch_topology: Build cacheinfo from primary CPU") Signed-off-by: Yicong Yang Reviewed-by: Pierre Gondois Reviewed-by: Sudeep Holla --- Change since v1: - Get rid of the goto label, per Pierre Link: https://lore.kernel.org/all/20230323122528.16691-1-yangyicong@huawei.= com/ drivers/base/cacheinfo.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index f6573c335f4c..f3903d002819 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -474,12 +474,18 @@ int detect_cache_attributes(unsigned int cpu) =20 populate_leaves: /* - * populate_cache_leaves() may completely setup the cache leaves and - * shared_cpu_map or it may leave it partially setup. + * If LLC is valid the cache leaves were already populated so just go to + * update the cpu map. */ - ret =3D populate_cache_leaves(cpu); - if (ret) - goto free_ci; + if (!last_level_cache_is_valid(cpu)) { + /* + * populate_cache_leaves() may completely setup the cache leaves and + * shared_cpu_map or it may leave it partially setup. + */ + ret =3D populate_cache_leaves(cpu); + if (ret) + goto free_ci; + } =20 /* * For systems using DT for cache hierarchy, fw_token --=20 2.24.0