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authorLinus Torvalds <torvalds@linux-foundation.org>2018-12-26 13:03:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-12-26 13:03:47 -0800
commiteed9688f8513189295887e5a27ec7f576754b60e (patch)
treec205a6fa6b8ee8a5a99179a0d42e40e4a713c450 /arch/x86/kernel/cpu/mce/therm_throt.c
parent72af84151fa7e98720a0482b59de2d90ec7f10a7 (diff)
parent72a8f089c382c078f8c7c1c759cb726de80d4284 (diff)
Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RAS updates from Borislav Petkov: "This time around we have a subsystem reorganization to offer, with the new directory being arch/x86/kernel/cpu/mce/ and all compilation units' names streamlined under it" * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Restore MCE injector's module name x86/mce: Unify pr_* prefix x86/mce: Streamline MCE subsystem's naming
Diffstat (limited to 'arch/x86/kernel/cpu/mce/therm_throt.c')
-rw-r--r--arch/x86/kernel/cpu/mce/therm_throt.c522
1 files changed, 522 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mce/therm_throt.c b/arch/x86/kernel/cpu/mce/therm_throt.c
new file mode 100644
index 000000000000..df01ff8513a5
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/therm_throt.c
@@ -0,0 +1,522 @@
+/*
+ * Thermal throttle event support code (such as syslog messaging and rate
+ * limiting) that was factored out from x86_64 (mce_intel.c) and i386 (p4.c).
+ *
+ * This allows consistent reporting of CPU thermal throttle events.
+ *
+ * Maintains a counter in /sys that keeps track of the number of thermal
+ * events, such that the user knows how bad the thermal problem might be
+ * (since the logging to syslog is rate limited).
+ *
+ * Author: Dmitriy Zavin (dmitriyz@google.com)
+ *
+ * Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
+ * Inspired by Ross Biro's and Al Borchers' counter code.
+ */
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+
+#include <asm/processor.h>
+#include <asm/apic.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+#include <asm/trace/irq_vectors.h>
+
+#include "internal.h"
+
+/* How long to wait between reporting thermal events */
+#define CHECK_INTERVAL (300 * HZ)
+
+#define THERMAL_THROTTLING_EVENT 0
+#define POWER_LIMIT_EVENT 1
+
+/*
+ * Current thermal event state:
+ */
+struct _thermal_state {
+ bool new_event;
+ int event;
+ u64 next_check;
+ unsigned long count;
+ unsigned long last_count;
+};
+
+struct thermal_state {
+ struct _thermal_state core_throttle;
+ struct _thermal_state core_power_limit;
+ struct _thermal_state package_throttle;
+ struct _thermal_state package_power_limit;
+ struct _thermal_state core_thresh0;
+ struct _thermal_state core_thresh1;
+ struct _thermal_state pkg_thresh0;
+ struct _thermal_state pkg_thresh1;
+};
+
+/* Callback to handle core threshold interrupts */
+int (*platform_thermal_notify)(__u64 msr_val);
+EXPORT_SYMBOL(platform_thermal_notify);
+
+/* Callback to handle core package threshold_interrupts */
+int (*platform_thermal_package_notify)(__u64 msr_val);
+EXPORT_SYMBOL_GPL(platform_thermal_package_notify);
+
+/* Callback support of rate control, return true, if
+ * callback has rate control */
+bool (*platform_thermal_package_rate_control)(void);
+EXPORT_SYMBOL_GPL(platform_thermal_package_rate_control);
+
+
+static DEFINE_PER_CPU(struct thermal_state, thermal_state);
+
+static atomic_t therm_throt_en = ATOMIC_INIT(0);
+
+static u32 lvtthmr_init __read_mostly;
+
+#ifdef CONFIG_SYSFS
+#define define_therm_throt_device_one_ro(_name) \
+ static DEVICE_ATTR(_name, 0444, \
+ therm_throt_device_show_##_name, \
+ NULL) \
+
+#define define_therm_throt_device_show_func(event, name) \
+ \
+static ssize_t therm_throt_device_show_##event##_##name( \
+ struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ unsigned int cpu = dev->id; \
+ ssize_t ret; \
+ \
+ preempt_disable(); /* CPU hotplug */ \
+ if (cpu_online(cpu)) { \
+ ret = sprintf(buf, "%lu\n", \
+ per_cpu(thermal_state, cpu).event.name); \
+ } else \
+ ret = 0; \
+ preempt_enable(); \
+ \
+ return ret; \
+}
+
+define_therm_throt_device_show_func(core_throttle, count);
+define_therm_throt_device_one_ro(core_throttle_count);
+
+define_therm_throt_device_show_func(core_power_limit, count);
+define_therm_throt_device_one_ro(core_power_limit_count);
+
+define_therm_throt_device_show_func(package_throttle, count);
+define_therm_throt_device_one_ro(package_throttle_count);
+
+define_therm_throt_device_show_func(package_power_limit, count);
+define_therm_throt_device_one_ro(package_power_limit_count);
+
+static struct attribute *thermal_throttle_attrs[] = {
+ &dev_attr_core_throttle_count.attr,
+ NULL
+};
+
+static const struct attribute_group thermal_attr_group = {
+ .attrs = thermal_throttle_attrs,
+ .name = "thermal_throttle"
+};
+#endif /* CONFIG_SYSFS */
+
+#define CORE_LEVEL 0
+#define PACKAGE_LEVEL 1
+
+/***
+ * therm_throt_process - Process thermal throttling event from interrupt
+ * @curr: Whether the condition is current or not (boolean), since the
+ * thermal interrupt normally gets called both when the thermal
+ * event begins and once the event has ended.
+ *
+ * This function is called by the thermal interrupt after the
+ * IRQ has been acknowledged.
+ *
+ * It will take care of rate limiting and printing messages to the syslog.
+ */
+static void therm_throt_process(bool new_event, int event, int level)
+{
+ struct _thermal_state *state;
+ unsigned int this_cpu = smp_processor_id();
+ bool old_event;
+ u64 now;
+ struct thermal_state *pstate = &per_cpu(thermal_state, this_cpu);
+
+ now = get_jiffies_64();
+ if (level == CORE_LEVEL) {
+ if (event == THERMAL_THROTTLING_EVENT)
+ state = &pstate->core_throttle;
+ else if (event == POWER_LIMIT_EVENT)
+ state = &pstate->core_power_limit;
+ else
+ return;
+ } else if (level == PACKAGE_LEVEL) {
+ if (event == THERMAL_THROTTLING_EVENT)
+ state = &pstate->package_throttle;
+ else if (event == POWER_LIMIT_EVENT)
+ state = &pstate->package_power_limit;
+ else
+ return;
+ } else
+ return;
+
+ old_event = state->new_event;
+ state->new_event = new_event;
+
+ if (new_event)
+ state->count++;
+
+ if (time_before64(now, state->next_check) &&
+ state->count != state->last_count)
+ return;
+
+ state->next_check = now + CHECK_INTERVAL;
+ state->last_count = state->count;
+
+ /* if we just entered the thermal event */
+ if (new_event) {
+ if (event == THERMAL_THROTTLING_EVENT)
+ pr_crit("CPU%d: %s temperature above threshold, cpu clock throttled (total events = %lu)\n",
+ this_cpu,
+ level == CORE_LEVEL ? "Core" : "Package",
+ state->count);
+ return;
+ }
+ if (old_event) {
+ if (event == THERMAL_THROTTLING_EVENT)
+ pr_info("CPU%d: %s temperature/speed normal\n", this_cpu,
+ level == CORE_LEVEL ? "Core" : "Package");
+ return;
+ }
+}
+
+static int thresh_event_valid(int level, int event)
+{
+ struct _thermal_state *state;
+ unsigned int this_cpu = smp_processor_id();
+ struct thermal_state *pstate = &per_cpu(thermal_state, this_cpu);
+ u64 now = get_jiffies_64();
+
+ if (level == PACKAGE_LEVEL)
+ state = (event == 0) ? &pstate->pkg_thresh0 :
+ &pstate->pkg_thresh1;
+ else
+ state = (event == 0) ? &pstate->core_thresh0 :
+ &pstate->core_thresh1;
+
+ if (time_before64(now, state->next_check))
+ return 0;
+
+ state->next_check = now + CHECK_INTERVAL;
+
+ return 1;
+}
+
+static bool int_pln_enable;
+static int __init int_pln_enable_setup(char *s)
+{
+ int_pln_enable = true;
+
+ return 1;
+}
+__setup("int_pln_enable", int_pln_enable_setup);
+
+#ifdef CONFIG_SYSFS
+/* Add/Remove thermal_throttle interface for CPU device: */
+static int thermal_throttle_add_dev(struct device *dev, unsigned int cpu)
+{
+ int err;
+ struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+ err = sysfs_create_group(&dev->kobj, &thermal_attr_group);
+ if (err)
+ return err;
+
+ if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
+ err = sysfs_add_file_to_group(&dev->kobj,
+ &dev_attr_core_power_limit_count.attr,
+ thermal_attr_group.name);
+ if (cpu_has(c, X86_FEATURE_PTS)) {
+ err = sysfs_add_file_to_group(&dev->kobj,
+ &dev_attr_package_throttle_count.attr,
+ thermal_attr_group.name);
+ if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
+ err = sysfs_add_file_to_group(&dev->kobj,
+ &dev_attr_package_power_limit_count.attr,
+ thermal_attr_group.name);
+ }
+
+ return err;
+}
+
+static void thermal_throttle_remove_dev(struct device *dev)
+{
+ sysfs_remove_group(&dev->kobj, &thermal_attr_group);
+}
+
+/* Get notified when a cpu comes on/off. Be hotplug friendly. */
+static int thermal_throttle_online(unsigned int cpu)
+{
+ struct device *dev = get_cpu_device(cpu);
+
+ return thermal_throttle_add_dev(dev, cpu);
+}
+
+static int thermal_throttle_offline(unsigned int cpu)
+{
+ struct device *dev = get_cpu_device(cpu);
+
+ thermal_throttle_remove_dev(dev);
+ return 0;
+}
+
+static __init int thermal_throttle_init_device(void)
+{
+ int ret;
+
+ if (!atomic_read(&therm_throt_en))
+ return 0;
+
+ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/therm:online",
+ thermal_throttle_online,
+ thermal_throttle_offline);
+ return ret < 0 ? ret : 0;
+}
+device_initcall(thermal_throttle_init_device);
+
+#endif /* CONFIG_SYSFS */
+
+static void notify_package_thresholds(__u64 msr_val)
+{
+ bool notify_thres_0 = false;
+ bool notify_thres_1 = false;
+
+ if (!platform_thermal_package_notify)
+ return;
+
+ /* lower threshold check */
+ if (msr_val & THERM_LOG_THRESHOLD0)
+ notify_thres_0 = true;
+ /* higher threshold check */
+ if (msr_val & THERM_LOG_THRESHOLD1)
+ notify_thres_1 = true;
+
+ if (!notify_thres_0 && !notify_thres_1)
+ return;
+
+ if (platform_thermal_package_rate_control &&
+ platform_thermal_package_rate_control()) {
+ /* Rate control is implemented in callback */
+ platform_thermal_package_notify(msr_val);
+ return;
+ }
+
+ /* lower threshold reached */
+ if (notify_thres_0 && thresh_event_valid(PACKAGE_LEVEL, 0))
+ platform_thermal_package_notify(msr_val);
+ /* higher threshold reached */
+ if (notify_thres_1 && thresh_event_valid(PACKAGE_LEVEL, 1))
+ platform_thermal_package_notify(msr_val);
+}
+
+static void notify_thresholds(__u64 msr_val)
+{
+ /* check whether the interrupt handler is defined;
+ * otherwise simply return
+ */
+ if (!platform_thermal_notify)
+ return;
+
+ /* lower threshold reached */
+ if ((msr_val & THERM_LOG_THRESHOLD0) &&
+ thresh_event_valid(CORE_LEVEL, 0))
+ platform_thermal_notify(msr_val);
+ /* higher threshold reached */
+ if ((msr_val & THERM_LOG_THRESHOLD1) &&
+ thresh_event_valid(CORE_LEVEL, 1))
+ platform_thermal_notify(msr_val);
+}
+
+/* Thermal transition interrupt handler */
+static void intel_thermal_interrupt(void)
+{
+ __u64 msr_val;
+
+ if (static_cpu_has(X86_FEATURE_HWP))
+ wrmsrl_safe(MSR_HWP_STATUS, 0);
+
+ rdmsrl(MSR_IA32_THERM_STATUS, msr_val);
+
+ /* Check for violation of core thermal thresholds*/
+ notify_thresholds(msr_val);
+
+ therm_throt_process(msr_val & THERM_STATUS_PROCHOT,
+ THERMAL_THROTTLING_EVENT,
+ CORE_LEVEL);
+
+ if (this_cpu_has(X86_FEATURE_PLN) && int_pln_enable)
+ therm_throt_process(msr_val & THERM_STATUS_POWER_LIMIT,
+ POWER_LIMIT_EVENT,
+ CORE_LEVEL);
+
+ if (this_cpu_has(X86_FEATURE_PTS)) {
+ rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
+ /* check violations of package thermal thresholds */
+ notify_package_thresholds(msr_val);
+ therm_throt_process(msr_val & PACKAGE_THERM_STATUS_PROCHOT,
+ THERMAL_THROTTLING_EVENT,
+ PACKAGE_LEVEL);
+ if (this_cpu_has(X86_FEATURE_PLN) && int_pln_enable)
+ therm_throt_process(msr_val &
+ PACKAGE_THERM_STATUS_POWER_LIMIT,
+ POWER_LIMIT_EVENT,
+ PACKAGE_LEVEL);
+ }
+}
+
+static void unexpected_thermal_interrupt(void)
+{
+ pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
+ smp_processor_id());
+}
+
+static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt;
+
+asmlinkage __visible void __irq_entry smp_thermal_interrupt(struct pt_regs *r)
+{
+ entering_irq();
+ trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
+ inc_irq_stat(irq_thermal_count);
+ smp_thermal_vector();
+ trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
+ exiting_ack_irq();
+}
+
+/* Thermal monitoring depends on APIC, ACPI and clock modulation */
+static int intel_thermal_supported(struct cpuinfo_x86 *c)
+{
+ if (!boot_cpu_has(X86_FEATURE_APIC))
+ return 0;
+ if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
+ return 0;
+ return 1;
+}
+
+void __init mcheck_intel_therm_init(void)
+{
+ /*
+ * This function is only called on boot CPU. Save the init thermal
+ * LVT value on BSP and use that value to restore APs' thermal LVT
+ * entry BIOS programmed later
+ */
+ if (intel_thermal_supported(&boot_cpu_data))
+ lvtthmr_init = apic_read(APIC_LVTTHMR);
+}
+
+void intel_init_thermal(struct cpuinfo_x86 *c)
+{
+ unsigned int cpu = smp_processor_id();
+ int tm2 = 0;
+ u32 l, h;
+
+ if (!intel_thermal_supported(c))
+ return;
+
+ /*
+ * First check if its enabled already, in which case there might
+ * be some SMM goo which handles it, so we can't even put a handler
+ * since it might be delivered via SMI already:
+ */
+ rdmsr(MSR_IA32_MISC_ENABLE, l, h);
+
+ h = lvtthmr_init;
+ /*
+ * The initial value of thermal LVT entries on all APs always reads
+ * 0x10000 because APs are woken up by BSP issuing INIT-SIPI-SIPI
+ * sequence to them and LVT registers are reset to 0s except for
+ * the mask bits which are set to 1s when APs receive INIT IPI.
+ * If BIOS takes over the thermal interrupt and sets its interrupt
+ * delivery mode to SMI (not fixed), it restores the value that the
+ * BIOS has programmed on AP based on BSP's info we saved since BIOS
+ * is always setting the same value for all threads/cores.
+ */
+ if ((h & APIC_DM_FIXED_MASK) != APIC_DM_FIXED)
+ apic_write(APIC_LVTTHMR, lvtthmr_init);
+
+
+ if ((l & MSR_IA32_MISC_ENABLE_TM1) && (h & APIC_DM_SMI)) {
+ if (system_state == SYSTEM_BOOTING)
+ pr_debug("CPU%d: Thermal monitoring handled by SMI\n", cpu);
+ return;
+ }
+
+ /* early Pentium M models use different method for enabling TM2 */
+ if (cpu_has(c, X86_FEATURE_TM2)) {
+ if (c->x86 == 6 && (c->x86_model == 9 || c->x86_model == 13)) {
+ rdmsr(MSR_THERM2_CTL, l, h);
+ if (l & MSR_THERM2_CTL_TM_SELECT)
+ tm2 = 1;
+ } else if (l & MSR_IA32_MISC_ENABLE_TM2)
+ tm2 = 1;
+ }
+
+ /* We'll mask the thermal vector in the lapic till we're ready: */
+ h = THERMAL_APIC_VECTOR | APIC_DM_FIXED | APIC_LVT_MASKED;
+ apic_write(APIC_LVTTHMR, h);
+
+ rdmsr(MSR_IA32_THERM_INTERRUPT, l, h);
+ if (cpu_has(c, X86_FEATURE_PLN) && !int_pln_enable)
+ wrmsr(MSR_IA32_THERM_INTERRUPT,
+ (l | (THERM_INT_LOW_ENABLE
+ | THERM_INT_HIGH_ENABLE)) & ~THERM_INT_PLN_ENABLE, h);
+ else if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
+ wrmsr(MSR_IA32_THERM_INTERRUPT,
+ l | (THERM_INT_LOW_ENABLE
+ | THERM_INT_HIGH_ENABLE | THERM_INT_PLN_ENABLE), h);
+ else
+ wrmsr(MSR_IA32_THERM_INTERRUPT,
+ l | (THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE), h);
+
+ if (cpu_has(c, X86_FEATURE_PTS)) {
+ rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
+ if (cpu_has(c, X86_FEATURE_PLN) && !int_pln_enable)
+ wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ (l | (PACKAGE_THERM_INT_LOW_ENABLE
+ | PACKAGE_THERM_INT_HIGH_ENABLE))
+ & ~PACKAGE_THERM_INT_PLN_ENABLE, h);
+ else if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
+ wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ l | (PACKAGE_THERM_INT_LOW_ENABLE
+ | PACKAGE_THERM_INT_HIGH_ENABLE
+ | PACKAGE_THERM_INT_PLN_ENABLE), h);
+ else
+ wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ l | (PACKAGE_THERM_INT_LOW_ENABLE
+ | PACKAGE_THERM_INT_HIGH_ENABLE), h);
+ }
+
+ smp_thermal_vector = intel_thermal_interrupt;
+
+ rdmsr(MSR_IA32_MISC_ENABLE, l, h);
+ wrmsr(MSR_IA32_MISC_ENABLE, l | MSR_IA32_MISC_ENABLE_TM1, h);
+
+ /* Unmask the thermal vector: */
+ l = apic_read(APIC_LVTTHMR);
+ apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
+
+ pr_info_once("CPU0: Thermal monitoring enabled (%s)\n",
+ tm2 ? "TM2" : "TM1");
+
+ /* enable thermal throttle processing */
+ atomic_set(&therm_throt_en, 1);
+}