Merge tag 'v5.5-rc5' into next

Sync up with mainline to get SPI "delay" API changes.

1 files changed, 24 insertions, 5 deletions

diff --git a/mm/swap.c b/mm/swap.c
index 38c3fa4308e2..5341ae93861f 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -373,9 +373,16 @@ static void __lru_cache_activate_page(struct page *page)
 void mark_page_accessed(struct page *page)
 {
 	page = compound_head(page);
-	if (!PageActive(page) && !PageUnevictable(page) &&
-			PageReferenced(page)) {
 
+	if (!PageReferenced(page)) {
+		SetPageReferenced(page);
+	} else if (PageUnevictable(page)) {
+		/*
+		 * Unevictable pages are on the "LRU_UNEVICTABLE" list. But,
+		 * this list is never rotated or maintained, so marking an
+		 * evictable page accessed has no effect.
+		 */
+	} else if (!PageActive(page)) {
 		/*
 		 * If the page is on the LRU, queue it for activation via
 		 * activate_page_pvecs. Otherwise, assume the page is on a
@@ -389,8 +396,6 @@ void mark_page_accessed(struct page *page)
 		ClearPageReferenced(page);
 		if (page_is_file_cache(page))
 			workingset_activation(page);
-	} else if (!PageReferenced(page)) {
-		SetPageReferenced(page);
 	}
 	if (page_is_idle(page))
 		clear_page_idle(page);
@@ -708,9 +713,10 @@ static void lru_add_drain_per_cpu(struct work_struct *dummy)
  */
 void lru_add_drain_all(void)
 {
+	static seqcount_t seqcount = SEQCNT_ZERO(seqcount);
 	static DEFINE_MUTEX(lock);
 	static struct cpumask has_work;
-	int cpu;
+	int cpu, seq;
 
 	/*
 	 * Make sure nobody triggers this path before mm_percpu_wq is fully
@@ -719,7 +725,19 @@ void lru_add_drain_all(void)
 	if (WARN_ON(!mm_percpu_wq))
 		return;
 
+	seq = raw_read_seqcount_latch(&seqcount);
+
 	mutex_lock(&lock);
+
+	/*
+	 * Piggyback on drain started and finished while we waited for lock:
+	 * all pages pended at the time of our enter were drained from vectors.
+	 */
+	if (__read_seqcount_retry(&seqcount, seq))
+		goto done;
+
+	raw_write_seqcount_latch(&seqcount);
+
 	cpumask_clear(&has_work);
 
 	for_each_online_cpu(cpu) {
@@ -740,6 +758,7 @@ void lru_add_drain_all(void)
 	for_each_cpu(cpu, &has_work)
 		flush_work(&per_cpu(lru_add_drain_work, cpu));
 
+done:
 	mutex_unlock(&lock);
 }
 #else