rcutorture: Limit reader duration if irq or bh disabled (1e696765) · Commits · 戴 / test

There are debug checks in some environments that will complain if the duration of a bh-disabled region of code exceeds about 50 milliseconds. Because rcu_read_delay() can produce a 50-millisecond delay and because there could be up to eight reader segments with such delays, this commit limits the maximum delay to 10 milliseconds if either interrupts or softirqs are disabled. Reported-by:

Thomas Gleixner <tglx@linutronix.de> Signed-off-by:

Paul E. McKenney <paulmck@linux.vnet.ibm.com>

kernel/rcu/rcutorture.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -323,7 +323,7 @@ static void rcu_read_delay(struct torture_random_state *rrsp)
		unsigned long started;
		unsigned long completed;
		const unsigned long shortdelay_us = 200;
		const unsigned long longdelay_ms = 300;
		unsigned long longdelay_ms = 300;
		unsigned long long ts;

		/* We want a short delay sometimes to make a reader delay the grace
		@@ -333,6 +333,8 @@ static void rcu_read_delay(struct torture_random_state *rrsp)
		if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) {
		started = cur_ops->get_gp_seq();
		ts = rcu_trace_clock_local();
		if (preempt_count() & (SOFTIRQ_MASK \| HARDIRQ_MASK))
		longdelay_ms = 5; /* Avoid triggering BH limits. */
		mdelay(longdelay_ms);
		completed = cur_ops->get_gp_seq();
		do_trace_rcu_torture_read(cur_ops->name, NULL, ts,

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