Commit-ID: 64ca5ab913f1594ef316556e65f5eae63ff50cee Gitweb: http://git.kernel.org/tip/64ca5ab913f1594ef316556e65f5eae63ff50cee Author: "Eric Dumazet" <dada1@xxxxxxxxxxxxx> AuthorDate: Wed, 4 Mar 2009 12:11:56 -0800 Commit: Ingo Molnar <mingo@xxxxxxx> CommitDate: Wed, 4 Mar 2009 22:08:45 +0100 rcu: increment quiescent state counter in ksoftirqd() If a machine is flooded by network frames, a cpu can loop 100% of its time inside ksoftirqd() without calling schedule(). This can delay RCU grace period to insane values. Adding rcu_qsctr_inc() call in ksoftirqd() solves this problem. Paul: "This regression was a result of the recent change from "schedule()" to "cond_resched()", which got rid of that quiescent state in the common case where a reschedule is not needed". Signed-off-by: Eric Dumazet <dada1@xxxxxxxxxxxxx> Reviewed-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- kernel/softirq.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/kernel/softirq.c b/kernel/softirq.c index bdbe9de..9041ea7 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -626,6 +626,7 @@ static int ksoftirqd(void * __bind_cpu) preempt_enable_no_resched(); cond_resched(); preempt_disable(); + rcu_qsctr_inc((long)__bind_cpu); } preempt_enable(); set_current_state(TASK_INTERRUPTIBLE); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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