diff options
| -rw-r--r-- | include/linux/irq_work.h | 2 | ||||
| -rw-r--r-- | kernel/events/core.c | 28 |
2 files changed, 23 insertions, 7 deletions
diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h index 6601702..add13c8 100644 --- a/include/linux/irq_work.h +++ b/include/linux/irq_work.h @@ -30,6 +30,8 @@ void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *)) work->func = func; } +#define DEFINE_IRQ_WORK(name, _f) struct irq_work name = { .func = (_f), } + void irq_work_queue(struct irq_work *work); void irq_work_run(void); void irq_work_sync(struct irq_work *work); diff --git a/kernel/events/core.c b/kernel/events/core.c index 56003c6..2067cbb 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -231,11 +231,29 @@ int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, #define NR_ACCUMULATED_SAMPLES 128 static DEFINE_PER_CPU(u64, running_sample_length); -void perf_sample_event_took(u64 sample_len_ns) +static void perf_duration_warn(struct irq_work *w) { + u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns); u64 avg_local_sample_len; u64 local_samples_len; + + local_samples_len = __get_cpu_var(running_sample_length); + avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES; + + printk_ratelimited(KERN_WARNING + "perf interrupt took too long (%lld > %lld), lowering " + "kernel.perf_event_max_sample_rate to %d\n", + avg_local_sample_len, allowed_ns, + sysctl_perf_event_sample_rate); +} + +static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); + +void perf_sample_event_took(u64 sample_len_ns) +{ u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns); + u64 avg_local_sample_len; + u64 local_samples_len; if (allowed_ns == 0) return; @@ -263,13 +281,9 @@ void perf_sample_event_took(u64 sample_len_ns) sysctl_perf_event_sample_rate = max_samples_per_tick * HZ; perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; - printk_ratelimited(KERN_WARNING - "perf samples too long (%lld > %lld), lowering " - "kernel.perf_event_max_sample_rate to %d\n", - avg_local_sample_len, allowed_ns, - sysctl_perf_event_sample_rate); - update_perf_cpu_limits(); + + irq_work_queue(&perf_duration_work); } static atomic64_t perf_event_id; |
