diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/softirq.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/kernel/softirq.c b/kernel/softirq.c index 43f2f53e4cba..b6ac17978c0e 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -57,11 +57,22 @@ static inline void wakeup_softirqd(void) wake_up_process(tsk); } +/* + * We restart softirq processing MAX_SOFTIRQ_RESTART times, + * and we fall back to softirqd after that. + * + * This number has 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 + asmlinkage void do_softirq(void) { + int max_restart = MAX_SOFTIRQ_RESTART; __u32 pending; unsigned long flags; - __u32 mask; if (in_interrupt()) return; @@ -73,7 +84,6 @@ asmlinkage void do_softirq(void) if (pending) { struct softirq_action *h; - mask = ~pending; local_bh_disable(); restart: /* Reset the pending bitmask before enabling irqs */ @@ -93,10 +103,8 @@ restart: local_irq_disable(); pending = local_softirq_pending(); - if (pending & mask) { - mask &= ~pending; + if (pending && --max_restart) goto restart; - } if (pending) wakeup_softirqd(); __local_bh_enable(); |