tick/rcu: Fix bogus ratelimit condition

[ Upstream commit a7e282c77785c7eabf98836431b1f029481085ad ]

The ratelimit logic in report_idle_softirq() is broken because the
exit condition is always true:

	static int ratelimit;

	if (ratelimit < 10)
		return false;  ---> always returns here

	ratelimit++;           ---> no chance to run

Make it check for >= 10 instead.

Fixes: 0345691b24c0 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle")
Signed-off-by: Wen Yang <wenyang.linux@foxmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/tencent_5AAA3EEAB42095C9B7740BE62FBF9A67E007@qq.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index d6fb6a6..1ad89ee 100644 (file)
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -1046,7 +1046,7 @@ static bool report_idle_softirq(void)
                        return false;
        }
 
-       if (ratelimit < 10)
+       if (ratelimit >= 10)
                return false;
 
        /* On RT, softirqs handling may be waiting on some lock */