diff options
Diffstat (limited to 'kernel/softirq.c')
-rw-r--r-- | kernel/softirq.c | 44 |
1 files changed, 21 insertions, 23 deletions
diff --git a/kernel/softirq.c b/kernel/softirq.c index ed567babe789..14d7758074aa 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -195,21 +195,21 @@ void local_bh_enable_ip(unsigned long ip) EXPORT_SYMBOL(local_bh_enable_ip); /* - * We restart softirq processing MAX_SOFTIRQ_RESTART times, - * and we fall back to softirqd after that. + * We restart softirq processing for at most 2 ms, + * and if need_resched() is not set. * - * This number has been established via experimentation. + * These limits have been established via experimentation. * The two things to balance is latency against fairness - * we want to handle softirqs as soon as possible, but they * should not be able to lock up the box. */ -#define MAX_SOFTIRQ_RESTART 10 +#define MAX_SOFTIRQ_TIME msecs_to_jiffies(2) asmlinkage void __do_softirq(void) { struct softirq_action *h; __u32 pending; - int max_restart = MAX_SOFTIRQ_RESTART; + unsigned long end = jiffies + MAX_SOFTIRQ_TIME; int cpu; unsigned long old_flags = current->flags; @@ -221,7 +221,7 @@ asmlinkage void __do_softirq(void) current->flags &= ~PF_MEMALLOC; pending = local_softirq_pending(); - vtime_account_irq_enter(current); + account_irq_enter_time(current); __local_bh_disable((unsigned long)__builtin_return_address(0), SOFTIRQ_OFFSET); @@ -264,15 +264,16 @@ restart: local_irq_disable(); pending = local_softirq_pending(); - if (pending && --max_restart) - goto restart; + if (pending) { + if (time_before(jiffies, end) && !need_resched()) + goto restart; - if (pending) wakeup_softirqd(); + } lockdep_softirq_exit(); - vtime_account_irq_exit(current); + account_irq_exit_time(current); __local_bh_enable(SOFTIRQ_OFFSET); tsk_restore_flags(current, old_flags, PF_MEMALLOC); } @@ -322,18 +323,10 @@ void irq_enter(void) static inline void invoke_softirq(void) { - if (!force_irqthreads) { -#ifdef __ARCH_IRQ_EXIT_IRQS_DISABLED + if (!force_irqthreads) __do_softirq(); -#else - do_softirq(); -#endif - } else { - __local_bh_disable((unsigned long)__builtin_return_address(0), - SOFTIRQ_OFFSET); + else wakeup_softirqd(); - __local_bh_enable(SOFTIRQ_OFFSET); - } } /* @@ -341,9 +334,15 @@ static inline void invoke_softirq(void) */ void irq_exit(void) { - vtime_account_irq_exit(current); +#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED + local_irq_disable(); +#else + WARN_ON_ONCE(!irqs_disabled()); +#endif + + account_irq_exit_time(current); trace_hardirq_exit(); - sub_preempt_count(IRQ_EXIT_OFFSET); + sub_preempt_count(HARDIRQ_OFFSET); if (!in_interrupt() && local_softirq_pending()) invoke_softirq(); @@ -353,7 +352,6 @@ void irq_exit(void) tick_nohz_irq_exit(); #endif rcu_irq_exit(); - sched_preempt_enable_no_resched(); } /* |