diff options
Diffstat (limited to 'kernel/softirq.c')
| -rw-r--r-- | kernel/softirq.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/kernel/softirq.c b/kernel/softirq.c index b5197dc..ca25e6e 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -127,8 +127,7 @@ static inline void __local_bh_disable(unsigned long ip, unsigned int cnt) void local_bh_disable(void) { - __local_bh_disable((unsigned long)__builtin_return_address(0), - SOFTIRQ_DISABLE_OFFSET); + __local_bh_disable(_RET_IP_, SOFTIRQ_DISABLE_OFFSET); } EXPORT_SYMBOL(local_bh_disable); @@ -139,7 +138,7 @@ static void __local_bh_enable(unsigned int cnt) WARN_ON_ONCE(!irqs_disabled()); if (softirq_count() == cnt) - trace_softirqs_on((unsigned long)__builtin_return_address(0)); + trace_softirqs_on(_RET_IP_); sub_preempt_count(cnt); } @@ -184,7 +183,7 @@ static inline void _local_bh_enable_ip(unsigned long ip) void local_bh_enable(void) { - _local_bh_enable_ip((unsigned long)__builtin_return_address(0)); + _local_bh_enable_ip(_RET_IP_); } EXPORT_SYMBOL(local_bh_enable); @@ -195,8 +194,12 @@ void local_bh_enable_ip(unsigned long ip) EXPORT_SYMBOL(local_bh_enable_ip); /* - * We restart softirq processing for at most 2 ms, - * and if need_resched() is not set. + * We restart softirq processing for at most MAX_SOFTIRQ_RESTART times, + * but break the loop if need_resched() is set or after 2 ms. + * The MAX_SOFTIRQ_TIME provides a nice upper bound in most cases, but in + * certain cases, such as stop_machine(), jiffies may cease to + * increment and so we need the MAX_SOFTIRQ_RESTART limit as + * well to make sure we eventually return from this method. * * These limits have been established via experimentation. * The two things to balance is latency against fairness - @@ -204,6 +207,7 @@ EXPORT_SYMBOL(local_bh_enable_ip); * should not be able to lock up the box. */ #define MAX_SOFTIRQ_TIME msecs_to_jiffies(2) +#define MAX_SOFTIRQ_RESTART 10 asmlinkage void __do_softirq(void) { @@ -212,6 +216,7 @@ asmlinkage void __do_softirq(void) unsigned long end = jiffies + MAX_SOFTIRQ_TIME; int cpu; unsigned long old_flags = current->flags; + int max_restart = MAX_SOFTIRQ_RESTART; /* * Mask out PF_MEMALLOC s current task context is borrowed for the @@ -223,8 +228,7 @@ asmlinkage void __do_softirq(void) pending = local_softirq_pending(); account_irq_enter_time(current); - __local_bh_disable((unsigned long)__builtin_return_address(0), - SOFTIRQ_OFFSET); + __local_bh_disable(_RET_IP_, SOFTIRQ_OFFSET); lockdep_softirq_enter(); cpu = smp_processor_id(); @@ -265,7 +269,8 @@ restart: pending = local_softirq_pending(); if (pending) { - if (time_before(jiffies, end) && !need_resched()) + if (time_before(jiffies, end) && !need_resched() && + --max_restart) goto restart; wakeup_softirqd(); |
