diff options
Diffstat (limited to 'drivers/base/cpu.c')
| -rw-r--r-- | drivers/base/cpu.c | 128 |
1 files changed, 108 insertions, 20 deletions
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 43dab03958f1..c6c57b6f61c6 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -19,13 +19,14 @@ #include <linux/cpufeature.h> #include <linux/tick.h> #include <linux/pm_qos.h> +#include <linux/delay.h> #include <linux/sched/isolation.h> #include "base.h" static DEFINE_PER_CPU(struct device *, cpu_sys_devices); -static int cpu_subsys_match(struct device *dev, struct device_driver *drv) +static int cpu_subsys_match(struct device *dev, const struct device_driver *drv) { /* ACPI style match is the only one that may succeed. */ if (acpi_driver_match_device(dev, drv)) @@ -50,12 +51,30 @@ static int cpu_subsys_online(struct device *dev) int cpuid = dev->id; int from_nid, to_nid; int ret; + int retries = 0; from_nid = cpu_to_node(cpuid); if (from_nid == NUMA_NO_NODE) return -ENODEV; +retry: ret = cpu_device_up(dev); + + /* + * If -EBUSY is returned, it is likely that hotplug is temporarily + * disabled when cpu_hotplug_disable() was called. This condition is + * transient. So we retry after waiting for an exponentially + * increasing delay up to a total of at least 620ms as some PCI + * device initialization can take quite a while. + */ + if (ret == -EBUSY) { + retries++; + if (retries > 5) + return ret; + msleep(10 * (1 << retries)); + goto retry; + } + /* * When hot adding memory to memoryless node and enabling a cpu * on the node, node number of the cpu may internally change. @@ -76,6 +95,7 @@ void unregister_cpu(struct cpu *cpu) { int logical_cpu = cpu->dev.id; + set_cpu_enabled(logical_cpu, false); unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu)); device_unregister(&cpu->dev); @@ -125,7 +145,7 @@ static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store); #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ #endif /* CONFIG_HOTPLUG_CPU */ -#ifdef CONFIG_KEXEC +#ifdef CONFIG_CRASH_DUMP #include <linux/kexec.h> static ssize_t crash_notes_show(struct device *dev, @@ -170,14 +190,14 @@ static const struct attribute_group crash_note_cpu_attr_group = { #endif static const struct attribute_group *common_cpu_attr_groups[] = { -#ifdef CONFIG_KEXEC +#ifdef CONFIG_CRASH_DUMP &crash_note_cpu_attr_group, #endif NULL }; static const struct attribute_group *hotplugable_cpu_attr_groups[] = { -#ifdef CONFIG_KEXEC +#ifdef CONFIG_CRASH_DUMP &crash_note_cpu_attr_group, #endif NULL @@ -254,6 +274,13 @@ static ssize_t print_cpus_offline(struct device *dev, } static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL); +static ssize_t print_cpus_enabled(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(cpu_enabled_mask)); +} +static DEVICE_ATTR(enabled, 0444, print_cpus_enabled, NULL); + static ssize_t print_cpus_isolated(struct device *dev, struct device_attribute *attr, char *buf) { @@ -273,13 +300,30 @@ static ssize_t print_cpus_isolated(struct device *dev, } static DEVICE_ATTR(isolated, 0444, print_cpus_isolated, NULL); +static ssize_t housekeeping_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct cpumask *hk_mask; + + hk_mask = housekeeping_cpumask(HK_TYPE_KERNEL_NOISE); + + if (housekeeping_enabled(HK_TYPE_KERNEL_NOISE)) + return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(hk_mask)); + return sysfs_emit(buf, "\n"); +} +static DEVICE_ATTR_RO(housekeeping); + #ifdef CONFIG_NO_HZ_FULL -static ssize_t print_cpus_nohz_full(struct device *dev, - struct device_attribute *attr, char *buf) +static ssize_t nohz_full_show(struct device *dev, + struct device_attribute *attr, + char *buf) { - return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(tick_nohz_full_mask)); + if (cpumask_available(tick_nohz_full_mask)) + return sysfs_emit(buf, "%*pbl\n", + cpumask_pr_args(tick_nohz_full_mask)); + return sysfs_emit(buf, "\n"); } -static DEVICE_ATTR(nohz_full, 0444, print_cpus_nohz_full, NULL); +static DEVICE_ATTR_RO(nohz_full); #endif #ifdef CONFIG_CRASH_HOTPLUG @@ -287,9 +331,9 @@ static ssize_t crash_hotplug_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sysfs_emit(buf, "%d\n", crash_hotplug_cpu_support()); + return sysfs_emit(buf, "%d\n", crash_check_hotplug_support()); } -static DEVICE_ATTR_ADMIN_RO(crash_hotplug); +static DEVICE_ATTR_RO(crash_hotplug); #endif static void cpu_device_release(struct device *dev) @@ -298,7 +342,7 @@ static void cpu_device_release(struct device *dev) * This is an empty function to prevent the driver core from spitting a * warning at us. Yes, I know this is directly opposite of what the * documentation for the driver core and kobjects say, and the author - * of this code has already been publically ridiculed for doing + * of this code has already been publicly ridiculed for doing * something as foolish as this. However, at this point in time, it is * the only way to handle the issue of statically allocated cpu * devices. The different architectures will have their cpu device @@ -347,7 +391,7 @@ static int cpu_uevent(const struct device *dev, struct kobj_uevent_env *env) } #endif -struct bus_type cpu_subsys = { +const struct bus_type cpu_subsys = { .name = "cpu", .dev_name = "cpu", .match = cpu_subsys_match, @@ -394,6 +438,7 @@ int register_cpu(struct cpu *cpu, int num) register_cpu_under_node(num, cpu_to_node(num)); dev_pm_qos_expose_latency_limit(&cpu->dev, PM_QOS_RESUME_LATENCY_NO_CONSTRAINT); + set_cpu_enabled(num, true); return 0; } @@ -475,7 +520,9 @@ static struct attribute *cpu_root_attrs[] = { &cpu_attrs[2].attr.attr, &dev_attr_kernel_max.attr, &dev_attr_offline.attr, + &dev_attr_enabled.attr, &dev_attr_isolated.attr, + &dev_attr_housekeeping.attr, #ifdef CONFIG_NO_HZ_FULL &dev_attr_nohz_full.attr, #endif @@ -506,19 +553,42 @@ bool cpu_is_hotpluggable(unsigned int cpu) EXPORT_SYMBOL_GPL(cpu_is_hotpluggable); #ifdef CONFIG_GENERIC_CPU_DEVICES -static DEFINE_PER_CPU(struct cpu, cpu_devices); -#endif +DEFINE_PER_CPU(struct cpu, cpu_devices); + +bool __weak arch_cpu_is_hotpluggable(int cpu) +{ + return false; +} + +int __weak arch_register_cpu(int cpu) +{ + struct cpu *c = &per_cpu(cpu_devices, cpu); + + c->hotpluggable = arch_cpu_is_hotpluggable(cpu); + + return register_cpu(c, cpu); +} + +#ifdef CONFIG_HOTPLUG_CPU +void __weak arch_unregister_cpu(int num) +{ + unregister_cpu(&per_cpu(cpu_devices, num)); +} +#endif /* CONFIG_HOTPLUG_CPU */ +#endif /* CONFIG_GENERIC_CPU_DEVICES */ static void __init cpu_dev_register_generic(void) { -#ifdef CONFIG_GENERIC_CPU_DEVICES - int i; + int i, ret; + + if (!IS_ENABLED(CONFIG_GENERIC_CPU_DEVICES)) + return; - for_each_possible_cpu(i) { - if (register_cpu(&per_cpu(cpu_devices, i), i)) - panic("Failed to register CPU device"); + for_each_present_cpu(i) { + ret = arch_register_cpu(i); + if (ret && ret != -EPROBE_DEFER) + pr_warn("register_cpu %d failed (%d)\n", i, ret); } -#endif } #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES @@ -546,6 +616,12 @@ CPU_SHOW_VULN_FALLBACK(mmio_stale_data); CPU_SHOW_VULN_FALLBACK(retbleed); CPU_SHOW_VULN_FALLBACK(spec_rstack_overflow); CPU_SHOW_VULN_FALLBACK(gds); +CPU_SHOW_VULN_FALLBACK(reg_file_data_sampling); +CPU_SHOW_VULN_FALLBACK(ghostwrite); +CPU_SHOW_VULN_FALLBACK(old_microcode); +CPU_SHOW_VULN_FALLBACK(indirect_target_selection); +CPU_SHOW_VULN_FALLBACK(tsa); +CPU_SHOW_VULN_FALLBACK(vmscape); static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL); static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL); @@ -560,6 +636,12 @@ static DEVICE_ATTR(mmio_stale_data, 0444, cpu_show_mmio_stale_data, NULL); static DEVICE_ATTR(retbleed, 0444, cpu_show_retbleed, NULL); static DEVICE_ATTR(spec_rstack_overflow, 0444, cpu_show_spec_rstack_overflow, NULL); static DEVICE_ATTR(gather_data_sampling, 0444, cpu_show_gds, NULL); +static DEVICE_ATTR(reg_file_data_sampling, 0444, cpu_show_reg_file_data_sampling, NULL); +static DEVICE_ATTR(ghostwrite, 0444, cpu_show_ghostwrite, NULL); +static DEVICE_ATTR(old_microcode, 0444, cpu_show_old_microcode, NULL); +static DEVICE_ATTR(indirect_target_selection, 0444, cpu_show_indirect_target_selection, NULL); +static DEVICE_ATTR(tsa, 0444, cpu_show_tsa, NULL); +static DEVICE_ATTR(vmscape, 0444, cpu_show_vmscape, NULL); static struct attribute *cpu_root_vulnerabilities_attrs[] = { &dev_attr_meltdown.attr, @@ -575,6 +657,12 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = { &dev_attr_retbleed.attr, &dev_attr_spec_rstack_overflow.attr, &dev_attr_gather_data_sampling.attr, + &dev_attr_reg_file_data_sampling.attr, + &dev_attr_ghostwrite.attr, + &dev_attr_old_microcode.attr, + &dev_attr_indirect_target_selection.attr, + &dev_attr_tsa.attr, + &dev_attr_vmscape.attr, NULL }; |