From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Mon, 11 Feb 2019 10:40:46 +0100
Subject: [PATCH] mm: workingset: replace IRQ-off check with a lockdep assert.
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/wagi/linux-stable-rt.git
Git-commit: d2b88172d5a172313230d7eaf48c0e55f433d6cc
Patch-mainline: Queued in subsystem maintainer repository
References: SLE Realtime Extension
Commit
68d48e6a2df57 ("mm: workingset: add vmstat counter for shadow nodes")
introduced an IRQ-off check to ensure that a lock is held which also
disabled interrupts. This does not work the same way on -RT because none
of the locks, that are held, disable interrupts.
Replace this check with a lockdep assert which ensures that the lock is
held.
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
mm/workingset.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -404,6 +404,8 @@ static struct list_lru shadow_nodes;
void workingset_update_node(struct xa_node *node)
{
+ struct address_space *mapping;
+
/*
* Track non-empty nodes that contain only shadow entries;
* unlink those that contain pages or are being freed.
@@ -412,7 +414,8 @@ void workingset_update_node(struct xa_no
* already where they should be. The list_empty() test is safe
* as node->private_list is protected by the i_pages lock.
*/
- VM_WARN_ON_ONCE(!irqs_disabled()); /* For __inc_lruvec_page_state */
+ mapping = container_of(node->array, struct address_space, i_pages);
+ lockdep_assert_held(&mapping->i_pages.xa_lock);
if (node->count && node->count == node->nr_values) {
if (list_empty(&node->private_list)) {