Commit 2386eef2 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Linus Torvalds
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mm: workingset: replace IRQ-off check with a lockdep assert. 

Commit 68d48e6a ("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 PREEMPT_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.

Link: https://lkml.kernel.org/r/20220301122143.1521823-3-bigeasy@linutronix.de


Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ff042f4a

mm/workingset.c

+4 −1
Original line number Diff line number Diff line
@@ -433,6 +433,8 @@ 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.
@@ -441,7 +443,8 @@ void workingset_update_node(struct xa_node *node) 
	 * 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)) {