From patchwork Tue Jul 20 11:26:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiongfeng Wang X-Patchwork-Id: 481653 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 56350C07E9B for ; Tue, 20 Jul 2021 11:20:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A59F61164 for ; Tue, 20 Jul 2021 11:20:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237498AbhGTKjg (ORCPT ); Tue, 20 Jul 2021 06:39:36 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:11456 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237176AbhGTKjb (ORCPT ); Tue, 20 Jul 2021 06:39:31 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4GTbkz2KWTzcgSR; Tue, 20 Jul 2021 19:16:43 +0800 (CST) Received: from dggpemm500002.china.huawei.com (7.185.36.229) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 20 Jul 2021 19:20:05 +0800 Received: from localhost.localdomain.localdomain (10.175.113.25) by dggpemm500002.china.huawei.com (7.185.36.229) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 20 Jul 2021 19:20:04 +0800 From: Xiongfeng Wang To: , , , , CC: , , , , Subject: [PATCH] ACPI / PPTT: get PPTT table in the first beginning Date: Tue, 20 Jul 2021 19:26:35 +0800 Message-ID: <20210720112635.38565-1-wangxiongfeng2@huawei.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-Originating-IP: [10.175.113.25] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500002.china.huawei.com (7.185.36.229) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org When I added might_sleep() in down_timeout(), I got the following Calltrace: [ 8.775671] BUG: sleeping function called from invalid context at kernel/locking/semaphore.c:160 [ 8.777070] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 14, name: cpuhp/0 [ 8.778474] CPU: 0 PID: 14 Comm: cpuhp/0 Not tainted 5.10.0-06616-g1fcfee258bd9-dirty #416 [ 8.782067] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 [ 8.783452] Call trace: [ 8.783878] dump_backtrace+0x0/0x1c0 [ 8.784512] show_stack+0x18/0x68 [ 8.784976] dump_stack+0xd8/0x134 [ 8.785428] ___might_sleep+0x108/0x170 [ 8.785928] __might_sleep+0x54/0x90 [ 8.786425] down_timeout+0x30/0x88 [ 8.786918] acpi_os_wait_semaphore+0x70/0xb8 [ 8.787483] acpi_ut_acquire_mutex+0x4c/0xb8 [ 8.788016] acpi_get_table+0x38/0xc4 [ 8.788521] acpi_find_last_cache_level+0x94/0x178 [ 8.789088] _init_cache_level+0xd0/0xe0 [ 8.789563] generic_exec_single+0xa0/0x100 [ 8.790122] smp_call_function_single+0x160/0x1e0 [ 8.790714] init_cache_level+0x38/0x60 [ 8.791247] cacheinfo_cpu_online+0x30/0x898 [ 8.791880] cpuhp_invoke_callback+0x88/0x258 [ 8.792707] cpuhp_thread_fun+0xd8/0x170 [ 8.793231] smpboot_thread_fn+0x194/0x290 [ 8.793838] kthread+0x15c/0x160 [ 8.794273] ret_from_fork+0x10/0x34 It is because generic_exec_single() will disable local irq before calling _init_cache_level(). _init_cache_level() use acpi_get_table() to get the PPTT table, but this function could schedule out. To fix this issue, we use a static pointer to record the mapped PPTT table in the first beginning. Later, we use that pointer to reference the PPTT table in acpi_find_last_cache_level(). We also modify other functions in pptt.c to use the pointer to reference PPTT table. Signed-off-by: Xiongfeng Wang --- arch/arm64/kernel/topology.c | 6 ++- drivers/acpi/pptt.c | 83 +++++++++++++++--------------------- include/linux/acpi.h | 1 + 3 files changed, 41 insertions(+), 49 deletions(-) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 4dd14a6620c1..401854bd8c48 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -83,11 +83,15 @@ static bool __init acpi_cpu_is_threaded(int cpu) */ int __init parse_acpi_topology(void) { - int cpu, topology_id; + int cpu, topology_id, ret; if (acpi_disabled) return 0; + ret = acpi_pptt_init(); + if (ret) + return ret; + for_each_possible_cpu(cpu) { int i, cache_id; diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index fe69dc518f31..a4c7af9e9369 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -21,6 +21,9 @@ #include #include +/* Root pointer to the mapped PPTT table */ +static struct acpi_table_header *pptt_table; + static struct acpi_subtable_header *fetch_pptt_subtable(struct acpi_table_header *table_hdr, u32 pptt_ref) { @@ -534,19 +537,13 @@ static int topology_get_acpi_cpu_tag(struct acpi_table_header *table, static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) { - struct acpi_table_header *table; - acpi_status status; int retval; - status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); + if (!pptt_table) return -ENOENT; - } - retval = topology_get_acpi_cpu_tag(table, cpu, level, flag); + retval = topology_get_acpi_cpu_tag(pptt_table, cpu, level, flag); pr_debug("Topology Setup ACPI CPU %d, level %d ret = %d\n", cpu, level, retval); - acpi_put_table(table); return retval; } @@ -566,26 +563,19 @@ static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) */ static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) { - struct acpi_table_header *table; - acpi_status status; u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); struct acpi_pptt_processor *cpu_node = NULL; int ret = -ENOENT; - status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); - return ret; - } + if (!pptt_table) + return -ENOENT; - if (table->revision >= rev) - cpu_node = acpi_find_processor_node(table, acpi_cpu_id); + if (pptt_table->revision >= rev) + cpu_node = acpi_find_processor_node(pptt_table, acpi_cpu_id); if (cpu_node) ret = (cpu_node->flags & flag) != 0; - acpi_put_table(table); - return ret; } @@ -602,20 +592,14 @@ static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) int acpi_find_last_cache_level(unsigned int cpu) { u32 acpi_cpu_id; - struct acpi_table_header *table; int number_of_levels = 0; - acpi_status status; pr_debug("Cache Setup find last level CPU=%d\n", cpu); acpi_cpu_id = get_acpi_id_for_cpu(cpu); - status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); - } else { - number_of_levels = acpi_find_cache_levels(table, acpi_cpu_id); - acpi_put_table(table); - } + if (pptt_table) + number_of_levels = acpi_find_cache_levels(pptt_table, acpi_cpu_id); + pr_debug("Cache Setup find last level level=%d\n", number_of_levels); return number_of_levels; @@ -636,21 +620,14 @@ int acpi_find_last_cache_level(unsigned int cpu) */ int cache_setup_acpi(unsigned int cpu) { - struct acpi_table_header *table; - acpi_status status; - pr_debug("Cache Setup ACPI CPU %d\n", cpu); - status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); + if (!pptt_table) return -ENOENT; - } - cache_setup_acpi_cpu(table, cpu); - acpi_put_table(table); + cache_setup_acpi_cpu(pptt_table, cpu); - return status; + return 0; } /** @@ -702,27 +679,20 @@ int find_acpi_cpu_topology(unsigned int cpu, int level) */ int find_acpi_cpu_cache_topology(unsigned int cpu, int level) { - struct acpi_table_header *table; struct acpi_pptt_cache *found_cache; - acpi_status status; u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); struct acpi_pptt_processor *cpu_node = NULL; int ret = -1; - status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); + if (!pptt_table) return -ENOENT; - } - found_cache = acpi_find_cache_node(table, acpi_cpu_id, + found_cache = acpi_find_cache_node(pptt_table, acpi_cpu_id, CACHE_TYPE_UNIFIED, level, &cpu_node); if (found_cache) - ret = ACPI_PTR_DIFF(cpu_node, table); - - acpi_put_table(table); + ret = ACPI_PTR_DIFF(cpu_node, pptt_table); return ret; } @@ -771,3 +741,20 @@ int find_acpi_cpu_topology_hetero_id(unsigned int cpu) return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, ACPI_PPTT_ACPI_IDENTICAL); } + +int __init acpi_pptt_init(void) +{ + acpi_status status; + + /* + * pptt_table will be used at runtime after acpi_pptt_init, so we don't + * need to call acpi_put_table() to release the PPTT table mapping. + */ + status = acpi_get_table(ACPI_SIG_PPTT, 0, &pptt_table); + if (ACPI_FAILURE(status)) { + acpi_pptt_warn_missing(); + return -ENOENT; + } + + return 0; +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 72e4f7fd268c..9263dc03dfb4 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1351,6 +1351,7 @@ static inline int lpit_read_residency_count_address(u64 *address) #endif #ifdef CONFIG_ACPI_PPTT +int acpi_pptt_init(void); int acpi_pptt_cpu_is_thread(unsigned int cpu); int find_acpi_cpu_topology(unsigned int cpu, int level); int find_acpi_cpu_topology_package(unsigned int cpu);