diff options
| -rw-r--r-- | include/linux/hardirq.h | 2 | ||||
| -rw-r--r-- | include/linux/sched.h | 13 | ||||
| -rw-r--r-- | kernel/sched.c | 49 |
3 files changed, 63 insertions, 1 deletions
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index a1c732ab0c76..a75d3a04ab68 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -137,7 +137,7 @@ extern void synchronize_irq(unsigned int irq); struct task_struct; -#ifndef CONFIG_VIRT_CPU_ACCOUNTING +#if !defined(CONFIG_VIRT_CPU_ACCOUNTING) && !defined(CONFIG_IRQ_TIME_ACCOUNTING) static inline void account_system_vtime(struct task_struct *tsk) { } diff --git a/include/linux/sched.h b/include/linux/sched.h index 63d5aea2b9fd..1ca5d041fccb 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1865,6 +1865,19 @@ extern void sched_clock_idle_wakeup_event(u64 delta_ns); */ extern unsigned long long cpu_clock(int cpu); +#ifdef CONFIG_IRQ_TIME_ACCOUNTING +/* + * An i/f to runtime opt-in for irq time accounting based off of sched_clock. + * The reason for this explicit opt-in is not to have perf penalty with + * slow sched_clocks. + */ +extern void enable_sched_clock_irqtime(void); +extern void disable_sched_clock_irqtime(void); +#else +static inline void enable_sched_clock_irqtime(void) {} +static inline void disable_sched_clock_irqtime(void) {} +#endif + extern unsigned long long task_sched_runtime(struct task_struct *task); extern unsigned long long thread_group_sched_runtime(struct task_struct *task); diff --git a/kernel/sched.c b/kernel/sched.c index fc1840961145..fe7082775973 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -1807,6 +1807,55 @@ static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) #endif } +#ifdef CONFIG_IRQ_TIME_ACCOUNTING + +static DEFINE_PER_CPU(u64, cpu_hardirq_time); +static DEFINE_PER_CPU(u64, cpu_softirq_time); + +static DEFINE_PER_CPU(u64, irq_start_time); +static int sched_clock_irqtime; + +void enable_sched_clock_irqtime(void) +{ + sched_clock_irqtime = 1; +} + +void disable_sched_clock_irqtime(void) +{ + sched_clock_irqtime = 0; +} + +void account_system_vtime(struct task_struct *curr) +{ + unsigned long flags; + int cpu; + u64 now, delta; + + if (!sched_clock_irqtime) + return; + + local_irq_save(flags); + + now = sched_clock(); + cpu = smp_processor_id(); + delta = now - per_cpu(irq_start_time, cpu); + per_cpu(irq_start_time, cpu) = now; + /* + * We do not account for softirq time from ksoftirqd here. + * We want to continue accounting softirq time to ksoftirqd thread + * in that case, so as not to confuse scheduler with a special task + * that do not consume any time, but still wants to run. + */ + if (hardirq_count()) + per_cpu(cpu_hardirq_time, cpu) += delta; + else if (in_serving_softirq() && !(curr->flags & PF_KSOFTIRQD)) + per_cpu(cpu_softirq_time, cpu) += delta; + + local_irq_restore(flags); +} + +#endif + #include "sched_stats.h" #include "sched_idletask.c" #include "sched_fair.c" |