This is a note to let you know that I've just added the patch titled
rcu: Fix up pending cbs check in rcu_prepare_for_idle
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rcu-fix-up-pending-cbs-check-in-rcu_prepare_for_idle.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 135bd1a230bb69a68c9808a7d25467318900b80a Mon Sep 17 00:00:00 2001
From: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx>
Date: Mon, 7 Aug 2017 11:20:10 +0530
Subject: rcu: Fix up pending cbs check in rcu_prepare_for_idle
From: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx>
commit 135bd1a230bb69a68c9808a7d25467318900b80a upstream.
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: 15fecf89e46a ("srcu: Abstract multi-tail callback list handling")
Signed-off-by: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree_plugin.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -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. */
Patches currently in stable-queue which might be from neeraju@xxxxxxxxxxxxxx are
queue-4.14/rcu-fix-up-pending-cbs-check-in-rcu_prepare_for_idle.patch