Commit 7a497c96 authored Aug 22, 2013 by Paul E. McKenney

rcu: Remove redundant code from rcu_cleanup_after_idle()



The rcu_try_advance_all_cbs() function returns a bool saying whether or
not there are callbacks ready to invoke, but rcu_cleanup_after_idle()
rechecks this regardless.  This commit therefore uses the value returned
by rcu_try_advance_all_cbs() instead of making rcu_cleanup_after_idle()
do this recheck.

Reported-by: Tibor Billes <tbilles@gmx.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tibor Billes <tbilles@gmx.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

parent 272b98c6

kernel/rcutree_plugin.h

+2 −8

Original line number	Diff line number	Diff line
		@@ -1768,18 +1768,12 @@ static void rcu_prepare_for_idle(int cpu)
		*/
		static void rcu_cleanup_after_idle(int cpu)
		{
		struct rcu_data *rdp;
		struct rcu_state *rsp;

		if (rcu_is_nocb_cpu(cpu))
		return;
		rcu_try_advance_all_cbs();
		for_each_rcu_flavor(rsp) {
		rdp = per_cpu_ptr(rsp->rda, cpu);
		if (cpu_has_callbacks_ready_to_invoke(rdp))
		if (rcu_try_advance_all_cbs())
		invoke_rcu_core();
		}
		}

		/*
		* Keep a running count of the number of non-lazy callbacks posted