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 Received: from picard.linux.it (picard.linux.it [213.254.12.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2B34AF9B611 for ; Wed, 22 Apr 2026 10:37:01 +0000 (UTC) Received: from picard.linux.it (localhost [IPv6:::1]) by picard.linux.it (Postfix) with ESMTP id 9C4213E53AC for ; Wed, 22 Apr 2026 12:36:59 +0200 (CEST) Received: from in-4.smtp.seeweb.it (in-4.smtp.seeweb.it [217.194.8.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by picard.linux.it (Postfix) with ESMTPS id 4853A3E2332 for ; Wed, 22 Apr 2026 12:36:39 +0200 (CEST) Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by in-4.smtp.seeweb.it (Postfix) with ESMTPS id 865E5100035D for ; Wed, 22 Apr 2026 12:36:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1776854198; x=1808390198; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=nTf2GTGYgOyYjFRWdkItPlYi+fPFO5GSMUXrVH1aBg8=; b=NPIgqDUaZc7hnnZk30Qn0jVAYzZbKGvVpiyLs6FyYs89sM/0LoYq6Qav G82EKBdQJfibBoyFzcLGkA+U2jPBuWS7KCmZa96JPw3Mee06Lf+O9fvMI jL2yubsNZlefudVDDGjXDC3vvWO5+iPxYV0hx0mWl3ghbqVzuY/g5EP9x nPk2icRnH6F5zvZXoCDnV2sCbJoA4wbeGX2GTpEM8TJSIwIkKWNdDXWuA qh6uDCxssJjRx/pwMEzMYeB0cLsNgmIobMo7W6BuBRGwwb/QrLq9dbKEx z613b+Nz4GQtC9fqUoV5fexjzPfclwLsrwQZIJiQgHlNMmEvYmQ3nw7Bj A==; X-CSE-ConnectionGUID: b98DHa9TSO+QaPvSDgkZug== X-CSE-MsgGUID: jnIr3s0yTial4h+zbIndpw== X-IronPort-AV: E=McAfee;i="6800,10657,11763"; a="89190714" X-IronPort-AV: E=Sophos;i="6.23,192,1770624000"; d="scan'208";a="89190714" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Apr 2026 03:36:34 -0700 X-CSE-ConnectionGUID: Q5IXrqWJRDei8BUynFRsoA== X-CSE-MsgGUID: R3ZXtRc5Rn+GkCi6Tqwjxg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,192,1770624000"; d="scan'208";a="234107963" Received: from pkubaj-desk.igk.intel.com (HELO intel.com) ([10.217.160.221]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Apr 2026 03:36:32 -0700 From: Piotr Kubaj To: ltp@lists.linux.it Date: Wed, 22 Apr 2026 12:35:43 +0200 Message-ID: <20260422103542.20933-2-piotr.kubaj@intel.com> X-Mailer: git-send-email 2.47.3 MIME-Version: 1.0 X-Virus-Scanned: clamav-milter 1.0.9 at in-4.smtp.seeweb.it X-Virus-Status: Clean Subject: [LTP] [PATCH] cpufreq.c: add new test for cpufreq sysfs interface validation X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: helena.anna.dubel@intel.com, tomasz.ossowski@intel.com, rafael.j.wysocki@intel.com, daniel.niestepski@intel.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Runs various sanity checks for intel_pstate cpufreq sysfs interface. Checks whether intel_pstate driver is used, whether it is possible to switch scaling_governor to powersave and performance, whether it is possible to disable turbo frequency and whether it is possible to change scaling_min_freq and scaling_max_freq to its minimal valid and maximal valid values. Signed-off-by: Piotr Kubaj --- runtest/power_management_tests | 1 + testcases/kernel/power_management/.gitignore | 1 + testcases/kernel/power_management/cpufreq.c | 355 +++++++++++++++++++ 3 files changed, 357 insertions(+) create mode 100644 testcases/kernel/power_management/cpufreq.c diff --git a/runtest/power_management_tests b/runtest/power_management_tests index 884e615cd..f235f8f0b 100644 --- a/runtest/power_management_tests +++ b/runtest/power_management_tests @@ -1,4 +1,5 @@ #POWER_MANAGEMENT +cpufreq cpufreq runpwtests01 runpwtests01.sh runpwtests02 runpwtests02.sh runpwtests03 runpwtests03.sh diff --git a/testcases/kernel/power_management/.gitignore b/testcases/kernel/power_management/.gitignore index 0c2a3ed4b..d0d7336ad 100644 --- a/testcases/kernel/power_management/.gitignore +++ b/testcases/kernel/power_management/.gitignore @@ -1 +1,2 @@ +cpufreq pm_get_sched_values diff --git a/testcases/kernel/power_management/cpufreq.c b/testcases/kernel/power_management/cpufreq.c new file mode 100644 index 000000000..379aac0fe --- /dev/null +++ b/testcases/kernel/power_management/cpufreq.c @@ -0,0 +1,355 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2026 Piotr Kubaj + */ + +/*\ + * Runs various sanity checks for intel_pstate cpufreq sysfs interface. + * + * Checks whether intel_pstate driver is used, whether it is possible to switch + * scaling_governor to powersave and performance, whether it is possible + * to disable turbo frequency and whether it is possible to change + * scaling_min_freq and scaling_max_freq to its minimal valid and maximal valid + * values. + */ + +#include "tst_test.h" + +static bool *online; +static char path[PATH_MAX], intel_pstate_status[16]; +static int no_turbo, nproc; +static long *previous_scaling_max_freq, *previous_scaling_min_freq; + +static void cleanup(void) +{ + SAFE_FILE_PRINTF("/sys/devices/system/cpu/intel_pstate/no_turbo", "%d", no_turbo); + SAFE_FILE_PRINTF("/sys/devices/system/cpu/intel_pstate/status", intel_pstate_status); + for (int i = 0; i < nproc; i++) { + if (!online[i]) + continue; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_max_freq", i); + SAFE_FILE_PRINTF(path, "%ld", previous_scaling_max_freq[i]); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_min_freq", i); + SAFE_FILE_PRINTF(path, "%ld", previous_scaling_min_freq[i]); + } + free(online); + free(previous_scaling_max_freq); + free(previous_scaling_min_freq); +} + +static void setup(void) +{ + SAFE_FILE_SCANF("/sys/devices/system/cpu/intel_pstate/no_turbo", "%d", &no_turbo); + SAFE_FILE_SCANF("/sys/devices/system/cpu/intel_pstate/status", "%15s", intel_pstate_status); + SAFE_FILE_PRINTF("/sys/devices/system/cpu/intel_pstate/status", "active"); + + nproc = tst_ncpus_conf(); + online = SAFE_CALLOC(nproc, sizeof(*online)); + previous_scaling_max_freq = SAFE_CALLOC(nproc, sizeof(*previous_scaling_max_freq)); + previous_scaling_min_freq = SAFE_CALLOC(nproc, sizeof(*previous_scaling_min_freq)); + online[0] = true; + for (int i = 1; i < nproc; i++) { + int tmp; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/online", i); + SAFE_FILE_SCANF(path, "%d", &tmp); + online[i] = (bool)tmp; + } +} + +static void run(void) +{ + const char * const cpufreq_nodes[] = { + "affected_cpus", + "cpuinfo_max_freq", + "cpuinfo_min_freq", + "cpuinfo_transition_latency", + "related_cpus", + "scaling_available_governors", + "scaling_cur_freq", + "scaling_driver", + "scaling_governor", + "scaling_max_freq", + "scaling_min_freq", + "scaling_setspeed", + NULL + }; + char contents[256] = {0}, path_cpuinfo_min_freq[PATH_MAX]; + int fd; + long cpuinfo_max_freq = 0, cpuinfo_min_freq = 0, scaling_max_freq, scaling_min_freq; + + for (int i = 0; i < nproc; i++) { + if (!online[i]) + continue; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_driver", i); + + SAFE_FILE_SCANF(path, "%255s", contents); + tst_res(TDEBUG, "Checking whether %s is \"intel_pstate\"", path); + if (strstr(contents, "intel_pstate")) + tst_res(TPASS, "%s is intel_pstate", path); + else { + tst_res(TINFO, "%s contains: %s", path, contents); + tst_res(TFAIL, "%s is not intel_pstate", path); + } + + for (int j = 0; cpufreq_nodes[j] != NULL; j++) { + struct stat stats; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/%s", i, cpufreq_nodes[j]); + tst_res(TDEBUG, "Checking whether %s is a regular file", path); + SAFE_STAT(path, &stats); + if (!S_ISREG(stats.st_mode)) { + tst_res(TINFO, "%s mode: %o\n", path, stats.st_mode); + tst_res(TFAIL, "%s is not a regular file", path); + } else + tst_res(TPASS, "%s is a regular file", path); + } + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_available_governors", i); + memset(contents, 0, sizeof(contents)); + fd = SAFE_OPEN(path, O_RDONLY); + SAFE_READ(0, fd, contents, sizeof(contents)); + SAFE_CLOSE(fd); + + tst_res(TDEBUG, "Checking whether %s is \"performance powersave\"", path); + if (strstr(contents, "performance powersave")) + tst_res(TPASS, "%s contains: %s", path, contents); + else { + tst_res(TINFO, "%s contains: %s", path, contents); + tst_res(TFAIL, "%s is not \"performance powersave\"", path); + } + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_governor", i); + tst_res(TDEBUG, "Checking %s", path); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + if (strstr(contents, "performance")) { + tst_res(TDEBUG, "%s is \"performance\"", path); + tst_res(TDEBUG, "Checking whether %s can be switched to \"powersave\"", path); + SAFE_FILE_PRINTF(path, "powersave"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + if (strstr(contents, "powersave")) + tst_res(TPASS, "Changing scaling_governor from performance to powersave succeeded"); + else + tst_res(TFAIL, "%s: failed to change scaling_governor from performance to powersave, current scaling_governor: %s", path, contents); + + } else if (strstr(contents, "powersave")) { + tst_res(TDEBUG, "%s is \"powersave\"", path); + tst_res(TDEBUG, "Checking whether %s can be switched to \"performance\"", path); + SAFE_FILE_PRINTF(path, "performance"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + if (strstr(contents, "performance")) + tst_res(TPASS, "Changing scaling_governor from powersave to performance succeeded"); + else + tst_res(TFAIL, "%s: failed to change scaling_governor from powersave to performance, current scaling_governor: %s", path, contents); + + } else + tst_brk(TBROK, "Unknown scaling_governor: %s", contents); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_max_freq", i); + snprintf(path_cpuinfo_min_freq, sizeof(path_cpuinfo_min_freq), "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_min_freq", i); + tst_res(TDEBUG, "Checking whether %s is bigger than cpuinfo_min_freq", path); + SAFE_FILE_SCANF(path, "%ld", &cpuinfo_max_freq); + + SAFE_FILE_SCANF(path_cpuinfo_min_freq, "%ld", &cpuinfo_min_freq); + + if (cpuinfo_min_freq > cpuinfo_max_freq) + tst_res(TFAIL, "Value in %s: %ld, should be bigger than cpuinfo_min_freq: %ld", path, cpuinfo_max_freq, cpuinfo_min_freq); + else + tst_res(TPASS, "Value in %s: %ld, is bigger than cpuinfo_min_freq: %ld", path, cpuinfo_max_freq, cpuinfo_min_freq); + } + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/intel_pstate/status"); + tst_res(TDEBUG, "Checking whether %s contains \"active\"", path); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "active")) + tst_res(TPASS, "%s is \"active\"", path); + else + tst_res(TFAIL, "%s is not \"active\", but %s", path, contents); + + tst_res(TDEBUG, "Checking whether %s can be switched to \"passive\"", path); + SAFE_FILE_PRINTF(path, "passive"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "passive")) + tst_res(TPASS, "%s is \"passive\"", path); + else + tst_res(TFAIL, "%s is not \"passive\", but %s", path, contents); + + tst_res(TDEBUG, "Checking whether %s can be switched back to \"active\"", path); + SAFE_FILE_PRINTF(path, "active"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "active")) + tst_res(TPASS, "%s is \"active\"", path); + else + tst_res(TFAIL, "%s is not \"active\", but %s", path, contents); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/intel_pstate/no_turbo"); + tst_res(TDEBUG, "Checking whether %s can be switched to 1", path); + SAFE_FILE_PRINTF(path, "1"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "1")) + tst_res(TPASS, "%s is \"1\"", path); + else + tst_res(TFAIL, "%s is not \"1\", but %s", path, contents); + + tst_res(TDEBUG, "Checking whether %s can be switched back to 0", path); + SAFE_FILE_PRINTF(path, "0"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "0")) + tst_res(TPASS, "%s is \"0\"", path); + else + tst_res(TFAIL, "%s is not \"0\", but %s", path, contents); + + tst_res(TDEBUG, "Checking whether scaling_available_governors changes to \"performance schedutil \" after switching /sys/devices/system/cpu/intel_pstate/status to \"passive\""); + snprintf(path, sizeof(path), "/sys/devices/system/cpu/intel_pstate/status"); + SAFE_FILE_PRINTF(path, "passive"); + + for (int i = 0; i < nproc; i++) { + if (!online[i]) + continue; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_available_governors", i); + memset(contents, 0, sizeof(contents)); + fd = SAFE_OPEN(path, O_RDONLY); + SAFE_READ(0, fd, contents, sizeof(contents)); + SAFE_CLOSE(fd); + + tst_res(TDEBUG, "Checking whether %s is \"performance schedutil\"", path); + if (strstr(contents, "performance schedutil")) + tst_res(TPASS, "%s contains: %s", path, contents); + else { + tst_res(TINFO, "%s contains: %s", path, contents); + tst_res(TFAIL, "%s is not \"performance schedutil \"", path); + } + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_governor", i); + tst_res(TDEBUG, "Checking whether %s can be changed to performance", path); + SAFE_FILE_PRINTF(path, "performance"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "performance")) + tst_res(TPASS, "%s is \"performance\"", path); + else + tst_res(TFAIL, "%s is not \"performance\", but %s", path, contents); + + tst_res(TDEBUG, "Checking whether %s can be changed to schedutil", path); + SAFE_FILE_PRINTF(path, "schedutil"); + memset(contents, 0, sizeof(contents)); + SAFE_FILE_SCANF(path, "%255s", contents); + + if (strstr(contents, "schedutil")) + tst_res(TPASS, "%s is \"schedutil\"", path); + else + tst_res(TFAIL, "%s is not \"schedutil\", but %s", path, contents); + } + + for (int i = 0; i < nproc; i++) { + if (!online[i]) + continue; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_max_freq", i); + tst_res(TDEBUG, "Checking whether %s can be assigned to scaling_max_freq and scaling_min_freq", path); + SAFE_FILE_SCANF(path, "%ld", &cpuinfo_max_freq); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_min_freq", i); + SAFE_FILE_SCANF(path, "%ld", &cpuinfo_min_freq); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_max_freq", i); + SAFE_FILE_SCANF(path, "%ld", &previous_scaling_max_freq[i]); + SAFE_FILE_PRINTF(path, "%ld", cpuinfo_max_freq); + SAFE_FILE_SCANF(path, "%ld", &scaling_max_freq); + + if (cpuinfo_max_freq < scaling_max_freq) { + tst_res(TINFO, "cpuinfo_max_freq: %ld", cpuinfo_max_freq); + tst_res(TINFO, "scaling_max_freq: %ld", scaling_max_freq); + tst_res(TFAIL, "Failure setting %s", path); + } else + tst_res(TPASS, "Successfully set up %s", path); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_min_freq", i); + SAFE_FILE_SCANF(path, "%ld", &previous_scaling_min_freq[i]); + SAFE_FILE_PRINTF(path, "%ld", cpuinfo_max_freq); + SAFE_FILE_SCANF(path, "%ld", &scaling_min_freq); + + if (cpuinfo_max_freq < scaling_min_freq) { + tst_res(TINFO, "cpuinfo_max_freq: %ld", cpuinfo_max_freq); + tst_res(TINFO, "scaling_min_freq: %ld", scaling_min_freq); + tst_res(TFAIL, "Failure setting %s", path); + } else + tst_res(TPASS, "Successfully set up %s", path); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_min_freq", i); + SAFE_FILE_PRINTF(path, "%ld", previous_scaling_min_freq[i]); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_max_freq", i); + SAFE_FILE_PRINTF(path, "%ld", previous_scaling_max_freq[i]); + } + + for (int i = 0; i < nproc; i++) { + if (!online[i]) + continue; + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_max_freq", i); + tst_res(TDEBUG, "Checking whether %s can be assigned to scaling_max_freq and scaling_min_freq", path); + SAFE_FILE_SCANF(path, "%ld", &cpuinfo_max_freq); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_min_freq", i); + SAFE_FILE_SCANF(path, "%ld", &cpuinfo_min_freq); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_min_freq", i); + SAFE_FILE_SCANF(path, "%ld", &previous_scaling_min_freq[i]); + SAFE_FILE_PRINTF(path, "%ld", cpuinfo_min_freq); + SAFE_FILE_SCANF(path, "%ld", &scaling_min_freq); + + if (cpuinfo_min_freq > scaling_min_freq) { + tst_res(TINFO, "cpuinfo_min_freq: %ld", cpuinfo_min_freq); + tst_res(TINFO, "scaling_min_freq: %ld", scaling_min_freq); + tst_res(TFAIL, "Failure setting %s", path); + } else + tst_res(TPASS, "Successfully set up %s", path); + + snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_max_freq", i); + SAFE_FILE_SCANF(path, "%ld", &previous_scaling_max_freq[i]); + SAFE_FILE_PRINTF(path, "%ld", cpuinfo_min_freq); + SAFE_FILE_SCANF(path, "%ld", &scaling_max_freq); + + if (cpuinfo_min_freq > scaling_max_freq) { + tst_res(TINFO, "cpuinfo_min_freq: %ld", cpuinfo_min_freq); + tst_res(TINFO, "scaling_max_freq: %ld", scaling_max_freq); + tst_res(TFAIL, "Failure setting %s", path); + } else + tst_res(TPASS, "Successfully set up %s", path); + } +} + +static struct tst_test test = { + .cleanup = cleanup, + .needs_kconfigs = (const char *const []) { + "CONFIG_X86_INTEL_PSTATE", + NULL + }, + .needs_root = 1, + .setup = setup, + .supported_archs = (const char *const []) { + "x86", + "x86_64", + NULL + }, + .test_all = run +}; -- 2.47.3 --------------------------------------------------------------------- Intel Technology Poland sp. z o.o. ul. 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