Merge tag 'linux-kselftest-next-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull Kselftest updates from Shuah Khan:
"Fixes and new tests:

- Add an amd-pstate-ut test module, used by kselftest to unit test
amd-pstate functionality

- Fixes and cleanups to to cpu-hotplug to delete the fault injection
test code

- Improvements to vm test to use top_srcdir for builds"

* tag 'linux-kselftest-next-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
docs:kselftest: fix kselftest_module.h path of example module
cpufreq: amd-pstate: Add explanation for X86_AMD_PSTATE_UT
selftests/cpu-hotplug: Add log info when test success
selftests/cpu-hotplug: Reserve one cpu online at least
selftests/cpu-hotplug: Delete fault injection related code
selftests/cpu-hotplug: Use return instead of exit
selftests/cpu-hotplug: Correct log info
cpufreq: amd-pstate: modify type in argument 2 for filp_open
Documentation: amd-pstate: Add unit test introduction
selftests: amd-pstate: Add test trigger for amd-pstate driver
cpufreq: amd-pstate: Add test module for amd-pstate driver
cpufreq: amd-pstate: Expose struct amd_cpudata
selftests/vm: use top_srcdir instead of recomputing relative paths

Documentation/admin-guide/pm/amd-pstate.rst

···
 Then, ``amd-pstate`` updates the desired performance according to the CPU
 scheduler assigned.
 
+.. _processor_support:
 
 Processor Support
 =======================
···
 
 Kernel Module Options for ``amd-pstate``
 =========================================
+
+.. _shared_mem:
 
 ``shared_mem``
 Use a module param (shared_mem) to enable related processors manually with
···
  CPU_005     712          116384        39        49        166       0.7565  9645075 2214891 38431470  25.1   11.646       469         2.496         kworker/5:0-40
  CPU_006     712          116408        39        49        166       0.6769  8950227 1839034 37192089  24.06  11.272       470         2.496         kworker/6:0-1264
 
+Unit Tests for amd-pstate
+-------------------------
+
+``amd-pstate-ut`` is a test module for testing the ``amd-pstate`` driver.
+
+ * It can help all users to verify their processor support (SBIOS/Firmware or Hardware).
+
+ * Kernel can have a basic function test to avoid the kernel regression during the update.
+
+ * We can introduce more functional or performance tests to align the result together, it will benefit power and performance scale optimization.
+
+1. Test case decriptions
+
+        +---------+--------------------------------+------------------------------------------------------------------------------------+
+        | Index   | Functions                      | Description                                                                        |
+        +=========+================================+====================================================================================+
+        | 0       | amd_pstate_ut_acpi_cpc_valid   || Check whether the _CPC object is present in SBIOS.                                |
+        |         |                                ||                                                                                   |
+        |         |                                || The detail refer to `Processor Support <processor_support_>`_.                    |
+        +---------+--------------------------------+------------------------------------------------------------------------------------+
+        | 1       | amd_pstate_ut_check_enabled    || Check whether AMD P-State is enabled.                                             |
+        |         |                                ||                                                                                   |
+        |         |                                || AMD P-States and ACPI hardware P-States always can be supported in one processor. |
+        |         |                                | But AMD P-States has the higher priority and if it is enabled with                 |
+        |         |                                | :c:macro:`MSR_AMD_CPPC_ENABLE` or ``cppc_set_enable``, it will respond to the      |
+        |         |                                | request from AMD P-States.                                                         |
+        +---------+--------------------------------+------------------------------------------------------------------------------------+
+        | 2       | amd_pstate_ut_check_perf       || Check if the each performance values are reasonable.                              |
+        |         |                                || highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0.           |
+        +---------+--------------------------------+------------------------------------------------------------------------------------+
+        | 3       | amd_pstate_ut_check_freq       || Check if the each frequency values and max freq when set support boost mode       |
+        |         |                                | are reasonable.                                                                    |
+        |         |                                || max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0                   |
+        |         |                                || If boost is not active but supported, this maximum frequency will be larger than  |
+        |         |                                | the one in ``cpuinfo``.                                                            |
+        +---------+--------------------------------+------------------------------------------------------------------------------------+
+
+#. How to execute the tests
+
+   We use test module in the kselftest frameworks to implement it.
+   We create amd-pstate-ut module and tie it into kselftest.(for
+   details refer to Linux Kernel Selftests [4]_).
+
+    1. Build
+
+        + open the :c:macro:`CONFIG_X86_AMD_PSTATE` configuration option.
+        + set the :c:macro:`CONFIG_X86_AMD_PSTATE_UT` configuration option to M.
+        + make project
+        + make selftest ::
+
+            $ cd linux
+            $ make -C tools/testing/selftests
+
+    #. Installation & Steps ::
+
+        $ make -C tools/testing/selftests install INSTALL_PATH=~/kselftest
+        $ sudo ./kselftest/run_kselftest.sh -c amd-pstate
+        TAP version 13
+        1..1
+        # selftests: amd-pstate: amd-pstate-ut.sh
+        # amd-pstate-ut: ok
+        ok 1 selftests: amd-pstate: amd-pstate-ut.sh
+
+    #. Results ::
+
+         $ dmesg | grep "amd_pstate_ut" | tee log.txt
+         [12977.570663] amd_pstate_ut: 1    amd_pstate_ut_acpi_cpc_valid  success!
+         [12977.570673] amd_pstate_ut: 2    amd_pstate_ut_check_enabled   success!
+         [12977.571207] amd_pstate_ut: 3    amd_pstate_ut_check_perf      success!
+         [12977.571212] amd_pstate_ut: 4    amd_pstate_ut_check_freq      success!
 
 Reference
 ===========
···
 
 .. [3] Processor Programming Reference (PPR) for AMD Family 19h Model 51h, Revision A1 Processors
        https://www.amd.com/system/files/TechDocs/56569-A1-PUB.zip
+
+.. [4] Linux Kernel Selftests,
+       https://www.kernel.org/doc/html/latest/dev-tools/kselftest.html

Documentation/dev-tools/kselftest.rst

···
 
    #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-   #include "../tools/testing/selftests/kselftest/module.h"
+   #include "../tools/testing/selftests/kselftest_module.h"
 
    KSTM_MODULE_GLOBALS();
 

MAINTAINERS

···
 S:	Supported
 F:	Documentation/admin-guide/pm/amd-pstate.rst
 F:	drivers/cpufreq/amd-pstate*
+F:	include/linux/amd-pstate.h
 F:	tools/power/x86/amd_pstate_tracer/amd_pstate_trace.py
 
 AMD PTDMA DRIVER

drivers/cpufreq/Kconfig.x86

···
 
 	  If in doubt, say N.
 
+config X86_AMD_PSTATE_UT
+	tristate "selftest for AMD Processor P-State driver"
+	depends on X86 && ACPI_PROCESSOR
+	default n
+	help
+	  This kernel module is used for testing. It's safe to say M here.
+
+	  It can also be built-in without X86_AMD_PSTATE enabled.
+	  Currently, only tests for amd-pstate are supported. If X86_AMD_PSTATE
+	  is set disabled, it can tell the users test can only run on amd-pstate
+	  driver, please set X86_AMD_PSTATE enabled.
+	  In the future, comparison tests will be added. It can set amd-pstate
+	  disabled and set acpi-cpufreq enabled to run test cases, then compare
+	  the test results.
+
 config X86_ACPI_CPUFREQ
 	tristate "ACPI Processor P-States driver"
 	depends on ACPI_PROCESSOR

drivers/cpufreq/Makefile

···
 
 obj-$(CONFIG_X86_ACPI_CPUFREQ)		+= acpi-cpufreq.o
 obj-$(CONFIG_X86_AMD_PSTATE)		+= amd_pstate.o
+obj-$(CONFIG_X86_AMD_PSTATE_UT)		+= amd-pstate-ut.o
 obj-$(CONFIG_X86_POWERNOW_K8)		+= powernow-k8.o
 obj-$(CONFIG_X86_PCC_CPUFREQ)		+= pcc-cpufreq.o
 obj-$(CONFIG_X86_POWERNOW_K6)		+= powernow-k6.o

drivers/cpufreq/amd-pstate-ut.c

···
+// SPDX-License-Identifier: GPL-1.0-or-later
+/*
+ * AMD Processor P-state Frequency Driver Unit Test
+ *
+ * Copyright (C) 2022 Advanced Micro Devices, Inc. All Rights Reserved.
+ *
+ * Author: Meng Li <[e-mail]>
+ *
+ * The AMD P-State Unit Test is a test module for testing the amd-pstate
+ * driver. 1) It can help all users to verify their processor support
+ * (SBIOS/Firmware or Hardware). 2) Kernel can have a basic function
+ * test to avoid the kernel regression during the update. 3) We can
+ * introduce more functional or performance tests to align the result
+ * together, it will benefit power and performance scale optimization.
+ *
+ * This driver implements basic framework with plans to enhance it with
+ * additional test cases to improve the depth and coverage of the test.
+ *
+ * See Documentation/admin-guide/pm/amd-pstate.rst Unit Tests for
+ * amd-pstate to get more detail.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/fs.h>
+#include <linux/amd-pstate.h>
+
+#include <acpi/cppc_acpi.h>
+
+/*
+ * Abbreviations:
+ * amd_pstate_ut: used as a shortform for AMD P-State unit test.
+ * It helps to keep variable names smaller, simpler
+ */
+enum amd_pstate_ut_result {
+	AMD_PSTATE_UT_RESULT_PASS,
+	AMD_PSTATE_UT_RESULT_FAIL,
+};
+
+struct amd_pstate_ut_struct {
+	const char *name;
+	void (*func)(u32 index);
+	enum amd_pstate_ut_result result;
+};
+
+/*
+ * Kernel module for testing the AMD P-State unit test
+ */
+static void amd_pstate_ut_acpi_cpc_valid(u32 index);
+static void amd_pstate_ut_check_enabled(u32 index);
+static void amd_pstate_ut_check_perf(u32 index);
+static void amd_pstate_ut_check_freq(u32 index);
+
+static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = {
+	{"amd_pstate_ut_acpi_cpc_valid",   amd_pstate_ut_acpi_cpc_valid   },
+	{"amd_pstate_ut_check_enabled",    amd_pstate_ut_check_enabled    },
+	{"amd_pstate_ut_check_perf",       amd_pstate_ut_check_perf       },
+	{"amd_pstate_ut_check_freq",       amd_pstate_ut_check_freq       }
+};
+
+static bool get_shared_mem(void)
+{
+	bool result = false;
+	char path[] = "/sys/module/amd_pstate/parameters/shared_mem";
+	char buf[5] = {0};
+	struct file *filp = NULL;
+	loff_t pos = 0;
+	ssize_t ret;
+
+	if (!boot_cpu_has(X86_FEATURE_CPPC)) {
+		filp = filp_open(path, O_RDONLY, 0);
+		if (IS_ERR(filp))
+			pr_err("%s unable to open %s file!\n", __func__, path);
+		else {
+			ret = kernel_read(filp, &buf, sizeof(buf), &pos);
+			if (ret < 0)
+				pr_err("%s read %s file fail ret=%ld!\n",
+					__func__, path, (long)ret);
+			filp_close(filp, NULL);
+		}
+
+		if ('Y' == *buf)
+			result = true;
+	}
+
+	return result;
+}
+
+/*
+ * check the _CPC object is present in SBIOS.
+ */
+static void amd_pstate_ut_acpi_cpc_valid(u32 index)
+{
+	if (acpi_cpc_valid())
+		amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
+	else {
+		amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+		pr_err("%s the _CPC object is not present in SBIOS!\n", __func__);
+	}
+}
+
+static void amd_pstate_ut_pstate_enable(u32 index)
+{
+	int ret = 0;
+	u64 cppc_enable = 0;
+
+	ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable);
+	if (ret) {
+		amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+		pr_err("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d error!\n", __func__, ret);
+		return;
+	}
+	if (cppc_enable)
+		amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
+	else {
+		amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+		pr_err("%s amd pstate must be enabled!\n", __func__);
+	}
+}
+
+/*
+ * check if amd pstate is enabled
+ */
+static void amd_pstate_ut_check_enabled(u32 index)
+{
+	if (get_shared_mem())
+		amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
+	else
+		amd_pstate_ut_pstate_enable(index);
+}
+
+/*
+ * check if performance values are reasonable.
+ * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0
+ */
+static void amd_pstate_ut_check_perf(u32 index)
+{
+	int cpu = 0, ret = 0;
+	u32 highest_perf = 0, nominal_perf = 0, lowest_nonlinear_perf = 0, lowest_perf = 0;
+	u64 cap1 = 0;
+	struct cppc_perf_caps cppc_perf;
+	struct cpufreq_policy *policy = NULL;
+	struct amd_cpudata *cpudata = NULL;
+
+	highest_perf = amd_get_highest_perf();
+
+	for_each_possible_cpu(cpu) {
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy)
+			break;
+		cpudata = policy->driver_data;
+
+		if (get_shared_mem()) {
+			ret = cppc_get_perf_caps(cpu, &cppc_perf);
+			if (ret) {
+				amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+				pr_err("%s cppc_get_perf_caps ret=%d error!\n", __func__, ret);
+				return;
+			}
+
+			nominal_perf = cppc_perf.nominal_perf;
+			lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf;
+			lowest_perf = cppc_perf.lowest_perf;
+		} else {
+			ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1);
+			if (ret) {
+				amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+				pr_err("%s read CPPC_CAP1 ret=%d error!\n", __func__, ret);
+				return;
+			}
+
+			nominal_perf = AMD_CPPC_NOMINAL_PERF(cap1);
+			lowest_nonlinear_perf = AMD_CPPC_LOWNONLIN_PERF(cap1);
+			lowest_perf = AMD_CPPC_LOWEST_PERF(cap1);
+		}
+
+		if ((highest_perf != READ_ONCE(cpudata->highest_perf)) ||
+			(nominal_perf != READ_ONCE(cpudata->nominal_perf)) ||
+			(lowest_nonlinear_perf != READ_ONCE(cpudata->lowest_nonlinear_perf)) ||
+			(lowest_perf != READ_ONCE(cpudata->lowest_perf))) {
+			amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+			pr_err("%s cpu%d highest=%d %d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d, they should be equal!\n",
+				__func__, cpu, highest_perf, cpudata->highest_perf,
+				nominal_perf, cpudata->nominal_perf,
+				lowest_nonlinear_perf, cpudata->lowest_nonlinear_perf,
+				lowest_perf, cpudata->lowest_perf);
+			return;
+		}
+
+		if (!((highest_perf >= nominal_perf) &&
+			(nominal_perf > lowest_nonlinear_perf) &&
+			(lowest_nonlinear_perf > lowest_perf) &&
+			(lowest_perf > 0))) {
+			amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+			pr_err("%s cpu%d highest=%d >= nominal=%d > lowest_nonlinear=%d > lowest=%d > 0, the formula is incorrect!\n",
+				__func__, cpu, highest_perf, nominal_perf,
+				lowest_nonlinear_perf, lowest_perf);
+			return;
+		}
+	}
+
+	amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
+}
+
+/*
+ * Check if frequency values are reasonable.
+ * max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0
+ * check max freq when set support boost mode.
+ */
+static void amd_pstate_ut_check_freq(u32 index)
+{
+	int cpu = 0;
+	struct cpufreq_policy *policy = NULL;
+	struct amd_cpudata *cpudata = NULL;
+
+	for_each_possible_cpu(cpu) {
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy)
+			break;
+		cpudata = policy->driver_data;
+
+		if (!((cpudata->max_freq >= cpudata->nominal_freq) &&
+			(cpudata->nominal_freq > cpudata->lowest_nonlinear_freq) &&
+			(cpudata->lowest_nonlinear_freq > cpudata->min_freq) &&
+			(cpudata->min_freq > 0))) {
+			amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+			pr_err("%s cpu%d max=%d >= nominal=%d > lowest_nonlinear=%d > min=%d > 0, the formula is incorrect!\n",
+				__func__, cpu, cpudata->max_freq, cpudata->nominal_freq,
+				cpudata->lowest_nonlinear_freq, cpudata->min_freq);
+			return;
+		}
+
+		if (cpudata->min_freq != policy->min) {
+			amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+			pr_err("%s cpu%d cpudata_min_freq=%d policy_min=%d, they should be equal!\n",
+				__func__, cpu, cpudata->min_freq, policy->min);
+			return;
+		}
+
+		if (cpudata->boost_supported) {
+			if ((policy->max == cpudata->max_freq) ||
+					(policy->max == cpudata->nominal_freq))
+				amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
+			else {
+				amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+				pr_err("%s cpu%d policy_max=%d should be equal cpu_max=%d or cpu_nominal=%d !\n",
+					__func__, cpu, policy->max, cpudata->max_freq,
+					cpudata->nominal_freq);
+				return;
+			}
+		} else {
+			amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
+			pr_err("%s cpu%d must support boost!\n", __func__, cpu);
+			return;
+		}
+	}
+
+	amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
+}
+
+static int __init amd_pstate_ut_init(void)
+{
+	u32 i = 0, arr_size = ARRAY_SIZE(amd_pstate_ut_cases);
+
+	for (i = 0; i < arr_size; i++) {
+		amd_pstate_ut_cases[i].func(i);
+		switch (amd_pstate_ut_cases[i].result) {
+		case AMD_PSTATE_UT_RESULT_PASS:
+			pr_info("%-4d %-20s\t success!\n", i+1, amd_pstate_ut_cases[i].name);
+			break;
+		case AMD_PSTATE_UT_RESULT_FAIL:
+		default:
+			pr_info("%-4d %-20s\t fail!\n", i+1, amd_pstate_ut_cases[i].name);
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static void __exit amd_pstate_ut_exit(void)
+{
+}
+
+module_init(amd_pstate_ut_init);
+module_exit(amd_pstate_ut_exit);
+
+MODULE_AUTHOR("Meng Li <[e-mail]>");
+MODULE_DESCRIPTION("AMD P-state driver Test module");
+MODULE_LICENSE("GPL");

drivers/cpufreq/amd-pstate.c

···
 #include <linux/delay.h>
 #include <linux/uaccess.h>
 #include <linux/static_call.h>
+#include <linux/amd-pstate.h>
 
 #include <acpi/processor.h>
 #include <acpi/cppc_acpi.h>
···
 		 "enable amd-pstate on processors with shared memory solution (false = disabled (default), true = enabled)");
 
 static struct cpufreq_driver amd_pstate_driver;
-
-/**
- * struct  amd_aperf_mperf
- * @aperf: actual performance frequency clock count
- * @mperf: maximum performance frequency clock count
- * @tsc:   time stamp counter
- */
-struct amd_aperf_mperf {
-	u64 aperf;
-	u64 mperf;
-	u64 tsc;
-};
-
-/**
- * struct amd_cpudata - private CPU data for AMD P-State
- * @cpu: CPU number
- * @req: constraint request to apply
- * @cppc_req_cached: cached performance request hints
- * @highest_perf: the maximum performance an individual processor may reach,
- *		  assuming ideal conditions
- * @nominal_perf: the maximum sustained performance level of the processor,
- *		  assuming ideal operating conditions
- * @lowest_nonlinear_perf: the lowest performance level at which nonlinear power
- *			   savings are achieved
- * @lowest_perf: the absolute lowest performance level of the processor
- * @max_freq: the frequency that mapped to highest_perf
- * @min_freq: the frequency that mapped to lowest_perf
- * @nominal_freq: the frequency that mapped to nominal_perf
- * @lowest_nonlinear_freq: the frequency that mapped to lowest_nonlinear_perf
- * @cur: Difference of Aperf/Mperf/tsc count between last and current sample
- * @prev: Last Aperf/Mperf/tsc count value read from register
- * @freq: current cpu frequency value
- * @boost_supported: check whether the Processor or SBIOS supports boost mode
- *
- * The amd_cpudata is key private data for each CPU thread in AMD P-State, and
- * represents all the attributes and goals that AMD P-State requests at runtime.
- */
-struct amd_cpudata {
-	int	cpu;
-
-	struct	freq_qos_request req[2];
-	u64	cppc_req_cached;
-
-	u32	highest_perf;
-	u32	nominal_perf;
-	u32	lowest_nonlinear_perf;
-	u32	lowest_perf;
-
-	u32	max_freq;
-	u32	min_freq;
-	u32	nominal_freq;
-	u32	lowest_nonlinear_freq;
-
-	struct amd_aperf_mperf cur;
-	struct amd_aperf_mperf prev;
-
-	u64 	freq;
-	bool	boost_supported;
-};
 
 static inline int pstate_enable(bool enable)
 {

include/linux/amd-pstate.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/include/linux/amd-pstate.h
+ *
+ * Copyright (C) 2022 Advanced Micro Devices, Inc.
+ *
+ * Author: Meng Li <[e-mail]>
+ */
+
+#ifndef _LINUX_AMD_PSTATE_H
+#define _LINUX_AMD_PSTATE_H
+
+#include <linux/pm_qos.h>
+
+/*********************************************************************
+ *                        AMD P-state INTERFACE                       *
+ *********************************************************************/
+/**
+ * struct  amd_aperf_mperf
+ * @aperf: actual performance frequency clock count
+ * @mperf: maximum performance frequency clock count
+ * @tsc:   time stamp counter
+ */
+struct amd_aperf_mperf {
+	u64 aperf;
+	u64 mperf;
+	u64 tsc;
+};
+
+/**
+ * struct amd_cpudata - private CPU data for AMD P-State
+ * @cpu: CPU number
+ * @req: constraint request to apply
+ * @cppc_req_cached: cached performance request hints
+ * @highest_perf: the maximum performance an individual processor may reach,
+ *		  assuming ideal conditions
+ * @nominal_perf: the maximum sustained performance level of the processor,
+ *		  assuming ideal operating conditions
+ * @lowest_nonlinear_perf: the lowest performance level at which nonlinear power
+ *			   savings are achieved
+ * @lowest_perf: the absolute lowest performance level of the processor
+ * @max_freq: the frequency that mapped to highest_perf
+ * @min_freq: the frequency that mapped to lowest_perf
+ * @nominal_freq: the frequency that mapped to nominal_perf
+ * @lowest_nonlinear_freq: the frequency that mapped to lowest_nonlinear_perf
+ * @cur: Difference of Aperf/Mperf/tsc count between last and current sample
+ * @prev: Last Aperf/Mperf/tsc count value read from register
+ * @freq: current cpu frequency value
+ * @boost_supported: check whether the Processor or SBIOS supports boost mode
+ *
+ * The amd_cpudata is key private data for each CPU thread in AMD P-State, and
+ * represents all the attributes and goals that AMD P-State requests at runtime.
+ */
+struct amd_cpudata {
+	int	cpu;
+
+	struct	freq_qos_request req[2];
+	u64	cppc_req_cached;
+
+	u32	highest_perf;
+	u32	nominal_perf;
+	u32	lowest_nonlinear_perf;
+	u32	lowest_perf;
+
+	u32	max_freq;
+	u32	min_freq;
+	u32	nominal_freq;
+	u32	lowest_nonlinear_freq;
+
+	struct amd_aperf_mperf cur;
+	struct amd_aperf_mperf prev;
+
+	u64	freq;
+	bool	boost_supported;
+};
+
+#endif /* _LINUX_AMD_PSTATE_H */

tools/testing/selftests/Makefile

···
 # SPDX-License-Identifier: GPL-2.0
 TARGETS += alsa
+TARGETS += amd-pstate
 TARGETS += arm64
 TARGETS += bpf
 TARGETS += breakpoints

tools/testing/selftests/amd-pstate/Makefile

···
+# SPDX-License-Identifier: GPL-2.0-only
+# Makefile for amd-pstate/ function selftests
+
+# No binaries, but make sure arg-less "make" doesn't trigger "run_tests"
+all:
+
+TEST_PROGS := amd-pstate-ut.sh
+
+include ../lib.mk

tools/testing/selftests/amd-pstate/amd-pstate-ut.sh

···
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+# amd-pstate-ut is a test module for testing the amd-pstate driver.
+# It can only run on x86 architectures and current cpufreq driver
+# must be amd-pstate.
+# (1) It can help all users to verify their processor support
+# (SBIOS/Firmware or Hardware).
+# (2) Kernel can have a basic function test to avoid the kernel
+# regression during the update.
+# (3) We can introduce more functional or performance tests to align
+# the result together, it will benefit power and performance scale optimization.
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+# amd-pstate-ut only run on x86/x86_64 AMD systems.
+ARCH=$(uname -m 2>/dev/null | sed -e 's/i.86/x86/' -e 's/x86_64/x86/')
+VENDOR=$(cat /proc/cpuinfo | grep -m 1 'vendor_id' | awk '{print $NF}')
+
+if ! echo "$ARCH" | grep -q x86; then
+	echo "$0 # Skipped: Test can only run on x86 architectures."
+	exit $ksft_skip
+fi
+
+if ! echo "$VENDOR" | grep -iq amd; then
+	echo "$0 # Skipped: Test can only run on AMD CPU."
+	echo "$0 # Current cpu vendor is $VENDOR."
+	exit $ksft_skip
+fi
+
+scaling_driver=$(cat /sys/devices/system/cpu/cpufreq/policy0/scaling_driver)
+if [ "$scaling_driver" != "amd-pstate" ]; then
+	echo "$0 # Skipped: Test can only run on amd-pstate driver."
+	echo "$0 # Please set X86_AMD_PSTATE enabled."
+	echo "$0 # Current cpufreq scaling drvier is $scaling_driver."
+	exit $ksft_skip
+fi
+
+msg="Skip all tests:"
+if [ ! -w /dev ]; then
+    echo $msg please run this as root >&2
+    exit $ksft_skip
+fi
+
+if ! /sbin/modprobe -q -n amd-pstate-ut; then
+	echo "amd-pstate-ut: module amd-pstate-ut is not found [SKIP]"
+	exit $ksft_skip
+fi
+if /sbin/modprobe -q amd-pstate-ut; then
+	/sbin/modprobe -q -r amd-pstate-ut
+	echo "amd-pstate-ut: ok"
+else
+	echo "amd-pstate-ut: [FAIL]"
+	exit 1
+fi

tools/testing/selftests/amd-pstate/config

···
+CONFIG_X86_AMD_PSTATE_UT=m

tools/testing/selftests/cpu-hotplug/Makefile

···
 include ../lib.mk
 
 run_full_test:
-	@/bin/bash ./cpu-on-off-test.sh -a || echo "cpu-hotplug selftests: [FAIL]"
+	@/bin/bash ./cpu-on-off-test.sh -a && echo "cpu-hotplug selftests: [PASS]" || echo "cpu-hotplug selftests: [FAIL]"
 
 clean:

tools/testing/selftests/cpu-hotplug/config

···
-CONFIG_NOTIFIER_ERROR_INJECTION=y

tools/testing/selftests/cpu-hotplug/cpu-on-off-test.sh

···
 SYSFS=
 # Kselftest framework requirement - SKIP code is 4.
 ksft_skip=4
+retval=0
 
 prerequisite()
 {
···
 
 	if ! online_cpu $cpu; then
 		echo $FUNCNAME $cpu: unexpected fail >&2
-		exit 1
+		retval=1
 	elif ! cpu_is_online $cpu; then
 		echo $FUNCNAME $cpu: unexpected offline >&2
-		exit 1
+		retval=1
 	fi
 }
 
···
 
 	if online_cpu $cpu 2> /dev/null; then
 		echo $FUNCNAME $cpu: unexpected success >&2
-		exit 1
+		retval=1
 	elif ! cpu_is_offline $cpu; then
 		echo $FUNCNAME $cpu: unexpected online >&2
-		exit 1
+		retval=1
 	fi
 }
 
···
 
 	if ! offline_cpu $cpu; then
 		echo $FUNCNAME $cpu: unexpected fail >&2
-		exit 1
+		retval=1
 	elif ! cpu_is_offline $cpu; then
 		echo $FUNCNAME $cpu: unexpected offline >&2
-		exit 1
+		retval=1
 	fi
 }
 
···
 
 	if offline_cpu $cpu 2> /dev/null; then
 		echo $FUNCNAME $cpu: unexpected success >&2
-		exit 1
+		retval=1
 	elif ! cpu_is_online $cpu; then
 		echo $FUNCNAME $cpu: unexpected offline >&2
-		exit 1
+		retval=1
 	fi
 }
 
-error=-12
+online_all_hot_pluggable_cpus()
+{
+	for cpu in `hotplaggable_offline_cpus`; do
+		online_cpu_expect_success $cpu
+	done
+}
+
+offline_all_hot_pluggable_cpus()
+{
+	local reserve_cpu=$online_max
+	for cpu in `hotpluggable_online_cpus`; do
+		# Reserve one cpu oneline at least.
+		if [ $cpu -eq $reserve_cpu ];then
+			continue
+		fi
+		offline_cpu_expect_success $cpu
+	done
+}
+
 allcpus=0
-priority=0
 online_cpus=0
 online_max=0
 offline_cpus=0
···
 present_cpus=0
 present_max=0
 
-while getopts e:ahp: opt; do
+while getopts ah opt; do
 	case $opt in
-	e)
-		error=$OPTARG
-		;;
 	a)
 		allcpus=1
 		;;
 	h)
-		echo "Usage $0 [ -a ] [ -e errno ] [ -p notifier-priority ]"
+		echo "Usage $0 [ -a ]"
 		echo -e "\t default offline one cpu"
 		echo -e "\t run with -a option to offline all cpus"
 		exit
 		;;
-	p)
-		priority=$OPTARG
-		;;
 	esac
 done
-
-if ! [ "$error" -ge -4095 -a "$error" -lt 0 ]; then
-	echo "error code must be -4095 <= errno < 0" >&2
-	exit 1
-fi
 
 prerequisite
 
···
 	online_cpu_expect_success $online_max
 
 	if [[ $offline_cpus -gt 0 ]]; then
-		echo -e "\t offline to online to offline: cpu $present_max"
+		echo -e "\t online to offline to online: cpu $present_max"
 		online_cpu_expect_success $present_max
 		offline_cpu_expect_success $present_max
 		online_cpu $present_max
 	fi
-	exit 0
+	exit $retval
 else
 	echo "Full scope test: all hotplug cpus"
 	echo -e "\t online all offline cpus"
···
 	echo -e "\t online all offline cpus"
 fi
 
-#
-# Online all hot-pluggable CPUs
-#
-for cpu in `hotplaggable_offline_cpus`; do
-	online_cpu_expect_success $cpu
-done
+online_all_hot_pluggable_cpus
 
-#
-# Offline all hot-pluggable CPUs
-#
-for cpu in `hotpluggable_online_cpus`; do
-	offline_cpu_expect_success $cpu
-done
+offline_all_hot_pluggable_cpus
 
-#
-# Online all hot-pluggable CPUs again
-#
-for cpu in `hotplaggable_offline_cpus`; do
-	online_cpu_expect_success $cpu
-done
+online_all_hot_pluggable_cpus
 
-#
-# Test with cpu notifier error injection
-#
-
-DEBUGFS=`mount -t debugfs | head -1 | awk '{ print $3 }'`
-NOTIFIER_ERR_INJECT_DIR=$DEBUGFS/notifier-error-inject/cpu
-
-prerequisite_extra()
-{
-	msg="skip extra tests:"
-
-	/sbin/modprobe -q -r cpu-notifier-error-inject
-	/sbin/modprobe -q cpu-notifier-error-inject priority=$priority
-
-	if [ ! -d "$DEBUGFS" ]; then
-		echo $msg debugfs is not mounted >&2
-		exit $ksft_skip
-	fi
-
-	if [ ! -d $NOTIFIER_ERR_INJECT_DIR ]; then
-		echo $msg cpu-notifier-error-inject module is not available >&2
-		exit $ksft_skip
-	fi
-}
-
-prerequisite_extra
-
-#
-# Offline all hot-pluggable CPUs
-#
-echo 0 > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_DOWN_PREPARE/error
-for cpu in `hotpluggable_online_cpus`; do
-	offline_cpu_expect_success $cpu
-done
-
-#
-# Test CPU hot-add error handling (offline => online)
-#
-echo $error > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_UP_PREPARE/error
-for cpu in `hotplaggable_offline_cpus`; do
-	online_cpu_expect_fail $cpu
-done
-
-#
-# Online all hot-pluggable CPUs
-#
-echo 0 > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_UP_PREPARE/error
-for cpu in `hotplaggable_offline_cpus`; do
-	online_cpu_expect_success $cpu
-done
-
-#
-# Test CPU hot-remove error handling (online => offline)
-#
-echo $error > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_DOWN_PREPARE/error
-for cpu in `hotpluggable_online_cpus`; do
-	offline_cpu_expect_fail $cpu
-done
-
-echo 0 > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_DOWN_PREPARE/error
-/sbin/modprobe -q -r cpu-notifier-error-inject
+exit $retval

tools/testing/selftests/vm/Makefile

···
 # LDLIBS.
 MAKEFLAGS += --no-builtin-rules
 
-CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS) $(KHDR_INCLUDES)
+CFLAGS = -Wall -I $(top_srcdir) -I $(top_srcdir)/usr/include $(EXTRA_CFLAGS) $(KHDR_INCLUDES)
 LDLIBS = -lrt -lpthread
 TEST_GEN_FILES = compaction_test
 TEST_GEN_FILES += gup_test

tools/testing/selftests/vm/gup_test.c

···
 #include <sys/types.h>
 #include <pthread.h>
 #include <assert.h>
-#include "../../../../mm/gup_test.h"
+#include <mm/gup_test.h>
 #include "../kselftest.h"
 
 #include "util.h"

tools/testing/selftests/vm/hmm-tests.c

···
  * This is a private UAPI to the kernel test module so it isn't exported
  * in the usual include/uapi/... directory.
  */
-#include "../../../../lib/test_hmm_uapi.h"
-#include "../../../../mm/gup_test.h"
+#include <lib/test_hmm_uapi.h>
+#include <mm/gup_test.h>
 
 struct hmm_buffer {
 	void		*ptr;

tools/testing/selftests/vm/ksm_tests.c

···
 #include <err.h>
 
 #include "../kselftest.h"
-#include "../../../../include/vdso/time64.h"
+#include <include/vdso/time64.h>
 #include "util.h"
 
 #define KSM_SYSFS_PATH "/sys/kernel/mm/ksm/"