summaryrefslogtreecommitdiffstats
path: root/debian/patches-rt/mm-workingset-replace-IRQ-off-check-with-a-lockdep-a.patch
blob: e5755e23baaa935045624301a1df1c11d000b0c8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
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.
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.21-rt34.tar.xz

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>
---
 mm/workingset.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -432,6 +432,8 @@ 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.
@@ -440,7 +442,8 @@ 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)) {