From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0FD631D7E26 for ; Wed, 16 Jul 2025 16:24:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752683089; cv=none; b=N66NKd2oOx2T+FLEmT90SeeTBstZ2Aqn0UrhUbgwcjxbvxodMbiBTItF8yRV2x+5aSSUIgT84VnaGIl3m+ft4ZX6hpF5g5EXGIoZCfyoFZ3JZpz4YurYrNgjSC4SV+asRpFGmiLDxqJ8/uoys6+lUXbZeDKtSVyYoZVqEGqFvnk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752683089; c=relaxed/simple; bh=+/NDUlNY0RLPdqCcIUp0BfcQXWxWZhXdyu0FfIKdXnM=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aUfJvFa1aLm+5eXeWrp3nHS9QtbP7sgzO/CGPwR0zpJWibMZix4zOwPQyu8dX4d9BjG++xu3sdvGCgACDDsvhXGd5cBf8T4WOPU+RtGvSvz1afRlFjGa5ofVg9rpK0VKroqz7spZx5U/qHBlHp7dupi8wB38La4GwsosNbbbSgs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.216]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4bj1Wq2sRbz6L4vM; Thu, 17 Jul 2025 00:21:11 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id 736DD1402F6; Thu, 17 Jul 2025 00:24:44 +0800 (CST) Received: from localhost (10.203.177.66) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Wed, 16 Jul 2025 18:24:43 +0200 Date: Wed, 16 Jul 2025 17:24:42 +0100 From: Jonathan Cameron To: James Morse CC: , , "Rob Herring" , Ben Horgan , Rohit Mathew , Shanker Donthineni , "Zeng Heng" , Lecopzer Chen , "Carl Worth" , , D Scott Phillips OS , , , , , Jamie Iles , Xin Hao , , , , David Hildenbrand , Rex Nie , Dave Martin , Koba Ko , Sudeep Holla Subject: Re: [RFC PATCH 08/36] ACPI / PPTT: Add a helper to fill a cpumask from a cache_id Message-ID: <20250716172442.000001d6@huawei.com> In-Reply-To: <20250711183648.30766-9-james.morse@arm.com> References: <20250711183648.30766-1-james.morse@arm.com> <20250711183648.30766-9-james.morse@arm.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml500004.china.huawei.com (7.191.163.9) To frapeml500008.china.huawei.com (7.182.85.71) On Fri, 11 Jul 2025 18:36:20 +0000 James Morse wrote: > MPAM identifies CPUs by the cache_id in the PPTT cache structure. > > The driver needs to know which CPUs are associated with the cache, > the CPUs may not all be online, so cacheinfo does not have the > information. > > Add a helper to pull this information out of the PPTT. > > CC: Rohit Mathew > Signed-off-by: James Morse > Reviewed-by: Sudeep Holla > --- > drivers/acpi/pptt.c | 70 ++++++++++++++++++++++++++++++++++++++++++++ > include/linux/acpi.h | 6 ++++ > 2 files changed, 76 insertions(+) > > diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c > index f53748a5df19..81f7ac18c023 100644 > --- a/drivers/acpi/pptt.c > +++ b/drivers/acpi/pptt.c > @@ -985,3 +985,73 @@ int find_acpi_cache_level_from_id(u32 cache_id) > acpi_put_table(table); > return -ENOENT; > } > + > +/** > + * acpi_pptt_get_cpumask_from_cache_id() - Get the cpus associated with the > + * specified cache > + * @cache_id: The id field of the unified cache > + * @cpus: Where to build the cpumask > + * > + * Determine which CPUs are below this cache in the PPTT. This allows the property > + * to be found even if the CPUs are offline. > + * > + * The PPTT table must be rev 3 or later, > + * > + * Return: -ENOENT if the PPTT doesn't exist, or the cache cannot be found. > + * Otherwise returns 0 and sets the cpus in the provided cpumask. > + */ > +int acpi_pptt_get_cpumask_from_cache_id(u32 cache_id, cpumask_t *cpus) > +{ > + u32 acpi_cpu_id; > + acpi_status status; > + int level, cpu, num_levels; > + struct acpi_pptt_cache *cache; > + struct acpi_table_header *table; > + struct acpi_pptt_cache_v1 *cache_v1; > + struct acpi_pptt_processor *cpu_node; > + > + cpumask_clear(cpus); > + > + status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); Similar suggestions to previous patch apply here as well. > + if (ACPI_FAILURE(status)) { > + acpi_pptt_warn_missing(); > + return -ENOENT; > + } > + > + if (table->revision < 3) { > + acpi_put_table(table); > + return -ENOENT; > + } > + > + /* > + * If we found the cache first, we'd still need to walk from each cpu. > + */ > + for_each_possible_cpu(cpu) { > + acpi_cpu_id = get_acpi_id_for_cpu(cpu); > + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); > + if (!cpu_node) > + break; > + acpi_count_levels(table, cpu_node, &num_levels, NULL); > + > + /* Start at 1 for L1 */ > + for (level = 1; level <= num_levels; level++) { > + cache = acpi_find_cache_node(table, acpi_cpu_id, > + ACPI_PPTT_CACHE_TYPE_UNIFIED, > + level, &cpu_node); > + if (!cache) > + continue; > + > + cache_v1 = ACPI_ADD_PTR(struct acpi_pptt_cache_v1, > + cache, > + sizeof(struct acpi_pptt_cache)); > + > + if (cache->flags & ACPI_PPTT_CACHE_ID_VALID && > + cache_v1->cache_id == cache_id) { > + cpumask_set_cpu(cpu, cpus); > + } Unnecessary {} Fine to keep them if you add something else here later. > + } > + } > + > + acpi_put_table(table); > + return 0; > +} > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index 82947f6d2a43..61ac3d1de1e8 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -1543,6 +1543,7 @@ int find_acpi_cpu_topology_package(unsigned int cpu); > int find_acpi_cpu_topology_hetero_id(unsigned int cpu); > int acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, cpumask_t *cpus); > int find_acpi_cache_level_from_id(u32 cache_id); > +int acpi_pptt_get_cpumask_from_cache_id(u32 cache_id, cpumask_t *cpus); > #else > static inline int acpi_pptt_cpu_is_thread(unsigned int cpu) > { > @@ -1573,6 +1574,11 @@ static inline int find_acpi_cache_level_from_id(u32 cache_id) > { > return -EINVAL; > } > +static inline int acpi_pptt_get_cpumask_from_cache_id(u32 cache_id, > + cpumask_t *cpus) > +{ > + return -EINVAL; > +} > #endif > > void acpi_arch_init(void);