Commit 135bd1a2 authored Aug 07, 2017 by Neeraj Upadhyay Committed by Paul E. McKenney Oct 09, 2017

rcu: Fix up pending cbs check in rcu_prepare_for_idle



The pending-callbacks check in rcu_prepare_for_idle() is backwards.
It should accelerate if there are pending callbacks, but the check
rather uselessly accelerates only if there are no callbacks.  This commit
therefore inverts this check.

Fixes: 15fecf89 ("srcu: Abstract multi-tail callback list handling")
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # 4.12.x

parent 8a5776a5

kernel/rcu/tree_plugin.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -1507,7 +1507,7 @@ static void rcu_prepare_for_idle(void)
		rdtp->last_accelerate = jiffies;
		for_each_rcu_flavor(rsp) {
		rdp = this_cpu_ptr(rsp->rda);
		if (rcu_segcblist_pend_cbs(&rdp->cblist))
		if (!rcu_segcblist_pend_cbs(&rdp->cblist))
		continue;
		rnp = rdp->mynode;
		raw_spin_lock_rcu_node(rnp); /* irqs already disabled. */

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