diff options
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/Kconfig | 9 | ||||
-rw-r--r-- | arch/x86/events/Makefile | 1 | ||||
-rw-r--r-- | arch/x86/events/amd/power.c | 353 | ||||
-rw-r--r-- | arch/x86/events/core.c | 4 |
4 files changed, 365 insertions, 2 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 8f2e665..a313c0e 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1206,6 +1206,15 @@ config MICROCODE_OLD_INTERFACE def_bool y depends on MICROCODE +config PERF_EVENTS_AMD_POWER + depends on PERF_EVENTS && CPU_SUP_AMD + tristate "AMD Processor Power Reporting Mechanism" + ---help--- + Provide power reporting mechanism support for AMD processors. + Currently, it leverages X86_FEATURE_ACC_POWER + (CPUID Fn8000_0007_EDX[12]) interface to calculate the + average power consumption on Family 15h processors. + config X86_MSR tristate "/dev/cpu/*/msr - Model-specific register support" ---help--- diff --git a/arch/x86/events/Makefile b/arch/x86/events/Makefile index fdfea15..f59618a 100644 --- a/arch/x86/events/Makefile +++ b/arch/x86/events/Makefile @@ -1,6 +1,7 @@ obj-y += core.o obj-$(CONFIG_CPU_SUP_AMD) += amd/core.o amd/uncore.o +obj-$(CONFIG_PERF_EVENTS_AMD_POWER) += amd/power.o obj-$(CONFIG_X86_LOCAL_APIC) += amd/ibs.o msr.o ifdef CONFIG_AMD_IOMMU obj-$(CONFIG_CPU_SUP_AMD) += amd/iommu.o diff --git a/arch/x86/events/amd/power.c b/arch/x86/events/amd/power.c new file mode 100644 index 0000000..55a3529 --- /dev/null +++ b/arch/x86/events/amd/power.c @@ -0,0 +1,353 @@ +/* + * Performance events - AMD Processor Power Reporting Mechanism + * + * Copyright (C) 2016 Advanced Micro Devices, Inc. + * + * Author: Huang Rui <ray.huang@amd.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/perf_event.h> +#include <asm/cpu_device_id.h> +#include "../perf_event.h" + +#define MSR_F15H_CU_PWR_ACCUMULATOR 0xc001007a +#define MSR_F15H_CU_MAX_PWR_ACCUMULATOR 0xc001007b +#define MSR_F15H_PTSC 0xc0010280 + +/* Event code: LSB 8 bits, passed in attr->config any other bit is reserved. */ +#define AMD_POWER_EVENT_MASK 0xFFULL + +/* + * Accumulated power status counters. + */ +#define AMD_POWER_EVENTSEL_PKG 1 + +/* + * The ratio of compute unit power accumulator sample period to the + * PTSC period. + */ +static unsigned int cpu_pwr_sample_ratio; + +/* Maximum accumulated power of a compute unit. */ +static u64 max_cu_acc_power; + +static struct pmu pmu_class; + +/* + * Accumulated power represents the sum of each compute unit's (CU) power + * consumption. On any core of each CU we read the total accumulated power from + * MSR_F15H_CU_PWR_ACCUMULATOR. cpu_mask represents CPU bit map of all cores + * which are picked to measure the power for the CUs they belong to. + */ +static cpumask_t cpu_mask; + +static void event_update(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + u64 prev_pwr_acc, new_pwr_acc, prev_ptsc, new_ptsc; + u64 delta, tdelta; + + prev_pwr_acc = hwc->pwr_acc; + prev_ptsc = hwc->ptsc; + rdmsrl(MSR_F15H_CU_PWR_ACCUMULATOR, new_pwr_acc); + rdmsrl(MSR_F15H_PTSC, new_ptsc); + + /* + * Calculate the CU power consumption over a time period, the unit of + * final value (delta) is micro-Watts. Then add it to the event count. + */ + if (new_pwr_acc < prev_pwr_acc) { + delta = max_cu_acc_power + new_pwr_acc; + delta -= prev_pwr_acc; + } else + delta = new_pwr_acc - prev_pwr_acc; + + delta *= cpu_pwr_sample_ratio * 1000; + tdelta = new_ptsc - prev_ptsc; + + do_div(delta, tdelta); + local64_add(delta, &event->count); +} + +static void __pmu_event_start(struct perf_event *event) +{ + if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED))) + return; + + event->hw.state = 0; + + rdmsrl(MSR_F15H_PTSC, event->hw.ptsc); + rdmsrl(MSR_F15H_CU_PWR_ACCUMULATOR, event->hw.pwr_acc); +} + +static void pmu_event_start(struct perf_event *event, int mode) +{ + __pmu_event_start(event); +} + +static void pmu_event_stop(struct perf_event *event, int mode) +{ + struct hw_perf_event *hwc = &event->hw; + + /* Mark event as deactivated and stopped. */ + if (!(hwc->state & PERF_HES_STOPPED)) + hwc->state |= PERF_HES_STOPPED; + + /* Check if software counter update is necessary. */ + if ((mode & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) { + /* + * Drain the remaining delta count out of an event + * that we are disabling: + */ + event_update(event); + hwc->state |= PERF_HES_UPTODATE; + } +} + +static int pmu_event_add(struct perf_event *event, int mode) +{ + struct hw_perf_event *hwc = &event->hw; + + hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED; + + if (mode & PERF_EF_START) + __pmu_event_start(event); + + return 0; +} + +static void pmu_event_del(struct perf_event *event, int flags) +{ + pmu_event_stop(event, PERF_EF_UPDATE); +} + +static int pmu_event_init(struct perf_event *event) +{ + u64 cfg = event->attr.config & AMD_POWER_EVENT_MASK; + + /* Only look at AMD power events. */ + if (event->attr.type != pmu_class.type) + return -ENOENT; + + /* Unsupported modes and filters. */ + if (event->attr.exclude_user || + event->attr.exclude_kernel || + event->attr.exclude_hv || + event->attr.exclude_idle || + event->attr.exclude_host || + event->attr.exclude_guest || + /* no sampling */ + event->attr.sample_period) + return -EINVAL; + + if (cfg != AMD_POWER_EVENTSEL_PKG) + return -EINVAL; + + return 0; +} + +static void pmu_event_read(struct perf_event *event) +{ + event_update(event); +} + +static ssize_t +get_attr_cpumask(struct device *dev, struct device_attribute *attr, char *buf) +{ + return cpumap_print_to_pagebuf(true, buf, &cpu_mask); +} + +static DEVICE_ATTR(cpumask, S_IRUGO, get_attr_cpumask, NULL); + +static struct attribute *pmu_attrs[] = { + &dev_attr_cpumask.attr, + NULL, +}; + +static struct attribute_group pmu_attr_group = { + .attrs = pmu_attrs, +}; + +/* + * Currently it only supports to report the power of each + * processor/package. + */ +EVENT_ATTR_STR(power-pkg, power_pkg, "event=0x01"); + +EVENT_ATTR_STR(power-pkg.unit, power_pkg_unit, "mWatts"); + +/* Convert the count from micro-Watts to milli-Watts. */ +EVENT_ATTR_STR(power-pkg.scale, power_pkg_scale, "1.000000e-3"); + +static struct attribute *events_attr[] = { + EVENT_PTR(power_pkg), + EVENT_PTR(power_pkg_unit), + EVENT_PTR(power_pkg_scale), + NULL, +}; + +static struct attribute_group pmu_events_group = { + .name = "events", + .attrs = events_attr, +}; + +PMU_FORMAT_ATTR(event, "config:0-7"); + +static struct attribute *formats_attr[] = { + &format_attr_event.attr, + NULL, +}; + +static struct attribute_group pmu_format_group = { + .name = "format", + .attrs = formats_attr, +}; + +static const struct attribute_group *attr_groups[] = { + &pmu_attr_group, + &pmu_format_group, + &pmu_events_group, + NULL, +}; + +static struct pmu pmu_class = { + .attr_groups = attr_groups, + /* system-wide only */ + .task_ctx_nr = perf_invalid_context, + .event_init = pmu_event_init, + .add = pmu_event_add, + .del = pmu_event_del, + .start = pmu_event_start, + .stop = pmu_event_stop, + .read = pmu_event_read, +}; + +static void power_cpu_exit(int cpu) +{ + int target; + + if (!cpumask_test_and_clear_cpu(cpu, &cpu_mask)) + return; + + /* + * Find a new CPU on the same compute unit, if was set in cpumask + * and still some CPUs on compute unit. Then migrate event and + * context to new CPU. + */ + target = cpumask_any_but(topology_sibling_cpumask(cpu), cpu); + if (target < nr_cpumask_bits) { + cpumask_set_cpu(target, &cpu_mask); + perf_pmu_migrate_context(&pmu_class, cpu, target); + } +} + +static void power_cpu_init(int cpu) +{ + int target; + + /* + * 1) If any CPU is set at cpu_mask in the same compute unit, do + * nothing. + * 2) If no CPU is set at cpu_mask in the same compute unit, + * set current STARTING CPU. + * + * Note: if there is a CPU aside of the new one already in the + * sibling mask, then it is also in cpu_mask. + */ + target = cpumask_any_but(topology_sibling_cpumask(cpu), cpu); + if (target >= nr_cpumask_bits) + cpumask_set_cpu(cpu, &cpu_mask); +} + +static int +power_cpu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) +{ + unsigned int cpu = (long)hcpu; + + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_DOWN_FAILED: + case CPU_STARTING: + power_cpu_init(cpu); + break; + case CPU_DOWN_PREPARE: + power_cpu_exit(cpu); + break; + default: + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block power_cpu_notifier_nb = { + .notifier_call = power_cpu_notifier, + .priority = CPU_PRI_PERF, +}; + +static const struct x86_cpu_id cpu_match[] = { + { .vendor = X86_VENDOR_AMD, .family = 0x15 }, + {}, +}; + +static int __init amd_power_pmu_init(void) +{ + int cpu, target, ret; + + if (!x86_match_cpu(cpu_match)) + return 0; + + if (!boot_cpu_has(X86_FEATURE_ACC_POWER)) + return -ENODEV; + + cpu_pwr_sample_ratio = cpuid_ecx(0x80000007); + + if (rdmsrl_safe(MSR_F15H_CU_MAX_PWR_ACCUMULATOR, &max_cu_acc_power)) { + pr_err("Failed to read max compute unit power accumulator MSR\n"); + return -ENODEV; + } + + cpu_notifier_register_begin(); + + /* Choose one online core of each compute unit. */ + for_each_online_cpu(cpu) { + target = cpumask_first(topology_sibling_cpumask(cpu)); + if (!cpumask_test_cpu(target, &cpu_mask)) + cpumask_set_cpu(target, &cpu_mask); + } + + ret = perf_pmu_register(&pmu_class, "power", -1); + if (WARN_ON(ret)) { + pr_warn("AMD Power PMU registration failed\n"); + goto out; + } + + __register_cpu_notifier(&power_cpu_notifier_nb); + + pr_info("AMD Power PMU detected\n"); + +out: + cpu_notifier_register_done(); + + return ret; +} +module_init(amd_power_pmu_init); + +static void __exit amd_power_pmu_exit(void) +{ + cpu_notifier_register_begin(); + __unregister_cpu_notifier(&power_cpu_notifier_nb); + cpu_notifier_register_done(); + + perf_pmu_unregister(&pmu_class); +} +module_exit(amd_power_pmu_exit); + +MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>"); +MODULE_DESCRIPTION("AMD Processor Power Reporting Mechanism"); +MODULE_LICENSE("GPL v2"); diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 5e830d0..002b2ea 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1602,8 +1602,7 @@ __init struct attribute **merge_attr(struct attribute **a, struct attribute **b) return new; } -ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, - char *page) +ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, char *page) { struct perf_pmu_events_attr *pmu_attr = \ container_of(attr, struct perf_pmu_events_attr, attr); @@ -1615,6 +1614,7 @@ ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, return x86_pmu.events_sysfs_show(page, config); } +EXPORT_SYMBOL_GPL(events_sysfs_show); EVENT_ATTR(cpu-cycles, CPU_CYCLES ); EVENT_ATTR(instructions, INSTRUCTIONS ); |