rcu: Dump ftrace buffer when kicking grace-period kthread



If it is necessary to kick the grace-period kthread, that is a good
time to dump the trace buffer in order to learn why kicking was needed.
This commit therefore does the dump.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

parent 293e2421

kernel/rcu/tree.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1266,6 +1266,7 @@ static void rcu_stall_kick_kthreads(struct rcu_state *rsp)
		j = READ_ONCE(rsp->jiffies_kick_kthreads);
		if (time_after(jiffies, j) && rsp->gp_kthread) {
		WARN_ONCE(1, "Kicking %s grace-period kthread\n", rsp->name);
		rcu_ftrace_dump(DUMP_ALL);
		wake_up_process(rsp->gp_kthread);
		WRITE_ONCE(rsp->jiffies_kick_kthreads, j + HZ);
		}