diff options
Diffstat (limited to 'arch/x86/events/core.c')
-rw-r--r-- | arch/x86/events/core.c | 140 |
1 files changed, 98 insertions, 42 deletions
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 91eac3962..d0efb5cb1 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -17,7 +17,8 @@ #include <linux/notifier.h> #include <linux/hardirq.h> #include <linux/kprobes.h> -#include <linux/module.h> +#include <linux/export.h> +#include <linux/init.h> #include <linux/kdebug.h> #include <linux/sched.h> #include <linux/uaccess.h> @@ -262,10 +263,13 @@ static bool check_hw_exists(void) return true; msr_fail: - pr_cont("Broken PMU hardware detected, using software events only.\n"); - printk("%sFailed to access perfctr msr (MSR %x is %Lx)\n", - boot_cpu_has(X86_FEATURE_HYPERVISOR) ? KERN_INFO : KERN_ERR, - reg, val_new); + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) { + pr_cont("PMU not available due to virtualization, using software events only.\n"); + } else { + pr_cont("Broken PMU hardware detected, using software events only.\n"); + pr_err("Failed to access perfctr msr (MSR %x is %Lx)\n", + reg, val_new); + } return false; } @@ -1477,49 +1481,49 @@ NOKPROBE_SYMBOL(perf_event_nmi_handler); struct event_constraint emptyconstraint; struct event_constraint unconstrained; -static int -x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) +static int x86_pmu_prepare_cpu(unsigned int cpu) { - unsigned int cpu = (long)hcpu; struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu); - int i, ret = NOTIFY_OK; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_UP_PREPARE: - for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) - cpuc->kfree_on_online[i] = NULL; - if (x86_pmu.cpu_prepare) - ret = x86_pmu.cpu_prepare(cpu); - break; - - case CPU_STARTING: - if (x86_pmu.cpu_starting) - x86_pmu.cpu_starting(cpu); - break; + int i; - case CPU_ONLINE: - for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) { - kfree(cpuc->kfree_on_online[i]); - cpuc->kfree_on_online[i] = NULL; - } - break; + for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) + cpuc->kfree_on_online[i] = NULL; + if (x86_pmu.cpu_prepare) + return x86_pmu.cpu_prepare(cpu); + return 0; +} - case CPU_DYING: - if (x86_pmu.cpu_dying) - x86_pmu.cpu_dying(cpu); - break; +static int x86_pmu_dead_cpu(unsigned int cpu) +{ + if (x86_pmu.cpu_dead) + x86_pmu.cpu_dead(cpu); + return 0; +} - case CPU_UP_CANCELED: - case CPU_DEAD: - if (x86_pmu.cpu_dead) - x86_pmu.cpu_dead(cpu); - break; +static int x86_pmu_online_cpu(unsigned int cpu) +{ + struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu); + int i; - default: - break; + for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) { + kfree(cpuc->kfree_on_online[i]); + cpuc->kfree_on_online[i] = NULL; } + return 0; +} - return ret; +static int x86_pmu_starting_cpu(unsigned int cpu) +{ + if (x86_pmu.cpu_starting) + x86_pmu.cpu_starting(cpu); + return 0; +} + +static int x86_pmu_dying_cpu(unsigned int cpu) +{ + if (x86_pmu.cpu_dying) + x86_pmu.cpu_dying(cpu); + return 0; } static void __init pmu_check_apic(void) @@ -1622,6 +1626,29 @@ ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, cha } EXPORT_SYMBOL_GPL(events_sysfs_show); +ssize_t events_ht_sysfs_show(struct device *dev, struct device_attribute *attr, + char *page) +{ + struct perf_pmu_events_ht_attr *pmu_attr = + container_of(attr, struct perf_pmu_events_ht_attr, attr); + + /* + * Report conditional events depending on Hyper-Threading. + * + * This is overly conservative as usually the HT special + * handling is not needed if the other CPU thread is idle. + * + * Note this does not (and cannot) handle the case when thread + * siblings are invisible, for example with virtualization + * if they are owned by some other guest. The user tool + * has to re-read when a thread sibling gets onlined later. + */ + return sprintf(page, "%s", + topology_max_smt_threads() > 1 ? + pmu_attr->event_str_ht : + pmu_attr->event_str_noht); +} + EVENT_ATTR(cpu-cycles, CPU_CYCLES ); EVENT_ATTR(instructions, INSTRUCTIONS ); EVENT_ATTR(cache-references, CACHE_REFERENCES ); @@ -1764,10 +1791,39 @@ static int __init init_hw_perf_events(void) pr_info("... fixed-purpose events: %d\n", x86_pmu.num_counters_fixed); pr_info("... event mask: %016Lx\n", x86_pmu.intel_ctrl); - perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW); - perf_cpu_notifier(x86_pmu_notifier); + /* + * Install callbacks. Core will call them for each online + * cpu. + */ + err = cpuhp_setup_state(CPUHP_PERF_X86_PREPARE, "PERF_X86_PREPARE", + x86_pmu_prepare_cpu, x86_pmu_dead_cpu); + if (err) + return err; + + err = cpuhp_setup_state(CPUHP_AP_PERF_X86_STARTING, + "AP_PERF_X86_STARTING", x86_pmu_starting_cpu, + x86_pmu_dying_cpu); + if (err) + goto out; + + err = cpuhp_setup_state(CPUHP_AP_PERF_X86_ONLINE, "AP_PERF_X86_ONLINE", + x86_pmu_online_cpu, NULL); + if (err) + goto out1; + + err = perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW); + if (err) + goto out2; return 0; + +out2: + cpuhp_remove_state(CPUHP_AP_PERF_X86_ONLINE); +out1: + cpuhp_remove_state(CPUHP_AP_PERF_X86_STARTING); +out: + cpuhp_remove_state(CPUHP_PERF_X86_PREPARE); + return err; } early_initcall(init_hw_perf_events); |