| Message ID | 20220519134737.359290-3-li.meng@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add unit test module for AMD P-State driver | expand |
On Thu, May 19, 2022 at 09:47:35PM +0800, Meng, Li (Jassmine) wrote: > Add amd-pstate-ut module, which is conceptually out-of-tree module > and provides ways for selftests/amd-pstate driver to test various > kernel module-related functionality. This module will be expected by > some of selftests to be present and loaded. > > Signed-off-by: Meng Li <li.meng@amd.com> > Acked-by: Huang Rui <ray.huang@amd.com> > --- > drivers/cpufreq/Kconfig.x86 | 6 + > drivers/cpufreq/Makefile | 1 + > drivers/cpufreq/amd-pstate-ut.c | 278 ++++++++++++++++++++++++++++++++ > 3 files changed, 285 insertions(+) > create mode 100644 drivers/cpufreq/amd-pstate-ut.c > > diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 > index 55516043b656..37ba282cd156 100644 > --- a/drivers/cpufreq/Kconfig.x86 > +++ b/drivers/cpufreq/Kconfig.x86 > @@ -51,6 +51,12 @@ config X86_AMD_PSTATE > > If in doubt, say N. > > +config X86_AMD_PSTATE_UT > + tristate "selftest for AMD Processor P-State driver" > + depends on X86_AMD_PSTATE I think we won't set X86_AMD_PSTATE as the depends of this module, because even if the acpi-cpufreq is loaded, this module can test it out and tell user the result. ACPI and ACPI_PROCESSOR should the dependencies. Thanks, Ray > + help > + This kernel module is used for testing. It's safe to say M here. > + > config X86_ACPI_CPUFREQ > tristate "ACPI Processor P-States driver" > depends on ACPI_PROCESSOR > diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile > index 285de70af877..49b98c62c5af 100644 > --- a/drivers/cpufreq/Makefile > +++ b/drivers/cpufreq/Makefile > @@ -30,6 +30,7 @@ amd_pstate-y := amd-pstate.o amd-pstate-trace.o > > 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 > diff --git a/drivers/cpufreq/amd-pstate-ut.c b/drivers/cpufreq/amd-pstate-ut.c > new file mode 100644 > index 000000000000..a510355b804e > --- /dev/null > +++ b/drivers/cpufreq/amd-pstate-ut.c > @@ -0,0 +1,278 @@ > +// 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 <li.meng@amd.com> > + * > + * 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. > + * > + * At present, it only implements the basic framework and some simple > + * test cases. Next, 1) we will add a rst document. 2) we will add more > + * test cases to improve the depth and coverage of the test. > + */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#include "../tools/testing/selftests/kselftest_module.h" > + > +#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: > + * aput: used as a shortform for AMD P-State unit test. > + * It helps to keep variable names smaller, simpler > + */ > + > +KSTM_MODULE_GLOBALS(); > + > +/* > + * Kernel module for testing the AMD P-State unit test > + */ > +enum aput_result { > + APUT_RESULT_PASS, > + APUT_RESULT_FAIL, > + MAX_APUT_RESULT, > +}; > + > +struct aput_struct { > + const char *name; > + void (*func)(u32 index); > + enum aput_result result; > +}; > + > +static void aput_acpi_cpc(u32 index); > +static void aput_check_enabled(u32 index); > +static void aput_check_perf(u32 index); > +static void aput_check_freq(u32 index); > + > +static struct aput_struct aput_cases[] = { > + {"acpi_cpc_valid", aput_acpi_cpc }, > + {"check_enabled", aput_check_enabled }, > + {"check_perf", aput_check_perf }, > + {"check_freq", aput_check_freq } > +}; > + > +static bool get_shared_mem(void) > +{ > + bool result = false; > + 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("/sys/module/amd_pstate/parameters/shared_mem", FMODE_PREAD, 0); > + if (IS_ERR(filp)) > + pr_err("%s Open param file fail!\n", __func__); > + else { > + ret = kernel_read(filp, &buf, sizeof(buf), &pos); > + if (ret < 0) > + pr_err("%s ret=%ld unable to read from param file!\n", > + __func__, ret); > + filp_close(filp, NULL); > + } > + > + if ('Y' == *buf) > + result = true; > + } > + > + return result; > +} > + > +static void aput_acpi_cpc(u32 index) > +{ > + if (acpi_cpc_valid()) > + aput_cases[index].result = APUT_RESULT_PASS; > + else > + aput_cases[index].result = APUT_RESULT_FAIL; > +} > + > +static void aput_pstate_enable(u32 index) > +{ > + int ret = 0; > + u64 cppc_enable = 0; > + > + ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable); > + if (ret) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d is error!\n", __func__, ret); > + return; > + } > + if (cppc_enable) > + aput_cases[index].result = APUT_RESULT_PASS; > + else > + aput_cases[index].result = APUT_RESULT_FAIL; > +} > + > +/* > + *Check if enabled amd pstate > + */ > +static void aput_check_enabled(u32 index) > +{ > + if (get_shared_mem()) > + aput_cases[index].result = APUT_RESULT_PASS; > + else > + aput_pstate_enable(index); > +} > + > +/* > + * Check if the each performance values are reasonable. > + * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0 > + */ > +static void aput_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) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cppc_get_perf_caps ret=%d is 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) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s read CPPC_CAP1 ret=%d is 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))) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cpu%d highest=%d %d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d are not 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))) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cpu%d highest=%d nominal=%d lowest_nonlinear=%d lowest=%d have error!\n", > + __func__, cpu, highest_perf, nominal_perf, > + lowest_nonlinear_perf, lowest_perf); > + return; > + } > + } > + > + aput_cases[index].result = APUT_RESULT_PASS; > +} > + > +/* > + * Check if the each frequency values are reasonable. > + * max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0 > + * check max freq when set support boost mode. > + */ > +static void aput_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))) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cpu%d max=%d nominal=%d lowest_nonlinear=%d min=%d have error!\n", > + __func__, cpu, cpudata->max_freq, cpudata->nominal_freq, > + cpudata->lowest_nonlinear_freq, cpudata->min_freq); > + return; > + } > + > + if (cpudata->min_freq != policy->min) { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cpu%d cpudata_min_freq=%d policy_min=%d have error!\n", > + __func__, cpu, cpudata->min_freq, policy->min); > + return; > + } > + > + if (cpudata->boost_supported) { > + if ((policy->max == cpudata->max_freq) || > + (policy->max == cpudata->nominal_freq)) > + aput_cases[index].result = APUT_RESULT_PASS; > + else { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cpu%d policy_max=%d cpu_max=%d cpu_nominal=%d have error!\n", > + __func__, cpu, policy->max, cpudata->max_freq, > + cpudata->nominal_freq); > + return; > + } > + } else { > + aput_cases[index].result = APUT_RESULT_FAIL; > + pr_err("%s cpu%d not support boost!\n", __func__, cpu); > + return; > + } > + } > +} > + > +static void aput_do_test_case(void) > +{ > + u32 i = 0, arr_size = ARRAY_SIZE(aput_cases); > + > + for (i = 0; i < arr_size; i++) { > + pr_info("****** Begin %-5d\t %-20s\t ******\n", i+1, aput_cases[i].name); > + aput_cases[i].func(i); > + KSTM_CHECK_ZERO(aput_cases[i].result); > + pr_info("****** End %-5d\t %-20s\t ******\n", i+1, aput_cases[i].name); > + } > +} > + > +static void __init selftest(void) > +{ > + aput_do_test_case(); > +} > + > +KSTM_MODULE_LOADERS(amd_pstate_ut); > +MODULE_AUTHOR("Meng Li <li.meng@amd.com>"); > +MODULE_DESCRIPTION("Unit test for AMD P-state driver"); > +MODULE_LICENSE("GPL"); > -- > 2.25.1 >
diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 index 55516043b656..37ba282cd156 100644 --- a/drivers/cpufreq/Kconfig.x86 +++ b/drivers/cpufreq/Kconfig.x86 @@ -51,6 +51,12 @@ config X86_AMD_PSTATE If in doubt, say N. +config X86_AMD_PSTATE_UT + tristate "selftest for AMD Processor P-State driver" + depends on X86_AMD_PSTATE + help + This kernel module is used for testing. It's safe to say M here. + config X86_ACPI_CPUFREQ tristate "ACPI Processor P-States driver" depends on ACPI_PROCESSOR diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 285de70af877..49b98c62c5af 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -30,6 +30,7 @@ amd_pstate-y := amd-pstate.o amd-pstate-trace.o 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 diff --git a/drivers/cpufreq/amd-pstate-ut.c b/drivers/cpufreq/amd-pstate-ut.c new file mode 100644 index 000000000000..a510355b804e --- /dev/null +++ b/drivers/cpufreq/amd-pstate-ut.c @@ -0,0 +1,278 @@ +// 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 <li.meng@amd.com> + * + * 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. + * + * At present, it only implements the basic framework and some simple + * test cases. Next, 1) we will add a rst document. 2) we will add more + * test cases to improve the depth and coverage of the test. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include "../tools/testing/selftests/kselftest_module.h" + +#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: + * aput: used as a shortform for AMD P-State unit test. + * It helps to keep variable names smaller, simpler + */ + +KSTM_MODULE_GLOBALS(); + +/* + * Kernel module for testing the AMD P-State unit test + */ +enum aput_result { + APUT_RESULT_PASS, + APUT_RESULT_FAIL, + MAX_APUT_RESULT, +}; + +struct aput_struct { + const char *name; + void (*func)(u32 index); + enum aput_result result; +}; + +static void aput_acpi_cpc(u32 index); +static void aput_check_enabled(u32 index); +static void aput_check_perf(u32 index); +static void aput_check_freq(u32 index); + +static struct aput_struct aput_cases[] = { + {"acpi_cpc_valid", aput_acpi_cpc }, + {"check_enabled", aput_check_enabled }, + {"check_perf", aput_check_perf }, + {"check_freq", aput_check_freq } +}; + +static bool get_shared_mem(void) +{ + bool result = false; + 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("/sys/module/amd_pstate/parameters/shared_mem", FMODE_PREAD, 0); + if (IS_ERR(filp)) + pr_err("%s Open param file fail!\n", __func__); + else { + ret = kernel_read(filp, &buf, sizeof(buf), &pos); + if (ret < 0) + pr_err("%s ret=%ld unable to read from param file!\n", + __func__, ret); + filp_close(filp, NULL); + } + + if ('Y' == *buf) + result = true; + } + + return result; +} + +static void aput_acpi_cpc(u32 index) +{ + if (acpi_cpc_valid()) + aput_cases[index].result = APUT_RESULT_PASS; + else + aput_cases[index].result = APUT_RESULT_FAIL; +} + +static void aput_pstate_enable(u32 index) +{ + int ret = 0; + u64 cppc_enable = 0; + + ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable); + if (ret) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d is error!\n", __func__, ret); + return; + } + if (cppc_enable) + aput_cases[index].result = APUT_RESULT_PASS; + else + aput_cases[index].result = APUT_RESULT_FAIL; +} + +/* + *Check if enabled amd pstate + */ +static void aput_check_enabled(u32 index) +{ + if (get_shared_mem()) + aput_cases[index].result = APUT_RESULT_PASS; + else + aput_pstate_enable(index); +} + +/* + * Check if the each performance values are reasonable. + * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0 + */ +static void aput_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) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cppc_get_perf_caps ret=%d is 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) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s read CPPC_CAP1 ret=%d is 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))) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cpu%d highest=%d %d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d are not 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))) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cpu%d highest=%d nominal=%d lowest_nonlinear=%d lowest=%d have error!\n", + __func__, cpu, highest_perf, nominal_perf, + lowest_nonlinear_perf, lowest_perf); + return; + } + } + + aput_cases[index].result = APUT_RESULT_PASS; +} + +/* + * Check if the each frequency values are reasonable. + * max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0 + * check max freq when set support boost mode. + */ +static void aput_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))) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cpu%d max=%d nominal=%d lowest_nonlinear=%d min=%d have error!\n", + __func__, cpu, cpudata->max_freq, cpudata->nominal_freq, + cpudata->lowest_nonlinear_freq, cpudata->min_freq); + return; + } + + if (cpudata->min_freq != policy->min) { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cpu%d cpudata_min_freq=%d policy_min=%d have error!\n", + __func__, cpu, cpudata->min_freq, policy->min); + return; + } + + if (cpudata->boost_supported) { + if ((policy->max == cpudata->max_freq) || + (policy->max == cpudata->nominal_freq)) + aput_cases[index].result = APUT_RESULT_PASS; + else { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cpu%d policy_max=%d cpu_max=%d cpu_nominal=%d have error!\n", + __func__, cpu, policy->max, cpudata->max_freq, + cpudata->nominal_freq); + return; + } + } else { + aput_cases[index].result = APUT_RESULT_FAIL; + pr_err("%s cpu%d not support boost!\n", __func__, cpu); + return; + } + } +} + +static void aput_do_test_case(void) +{ + u32 i = 0, arr_size = ARRAY_SIZE(aput_cases); + + for (i = 0; i < arr_size; i++) { + pr_info("****** Begin %-5d\t %-20s\t ******\n", i+1, aput_cases[i].name); + aput_cases[i].func(i); + KSTM_CHECK_ZERO(aput_cases[i].result); + pr_info("****** End %-5d\t %-20s\t ******\n", i+1, aput_cases[i].name); + } +} + +static void __init selftest(void) +{ + aput_do_test_case(); +} + +KSTM_MODULE_LOADERS(amd_pstate_ut); +MODULE_AUTHOR("Meng Li <li.meng@amd.com>"); +MODULE_DESCRIPTION("Unit test for AMD P-state driver"); +MODULE_LICENSE("GPL");