[PATCH 1/9] mm: vmstat: fix stat_threshold for NR_KERNEL_STACK_KB

[Muchun Song <songmuchun@xxxxxxxxxxxxx>]

The kernel stack is being accounted in KiB not page, so the
stat_threshold should also adjust to byte.

Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
 mm/vmstat.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 8d77ee426e22..f7857a7052e4 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -353,6 +353,8 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
 	x = delta + __this_cpu_read(*p);
 
 	t = __this_cpu_read(pcp->stat_threshold);
+	if (unlikely(item == NR_KERNEL_STACK_KB))
+		t <<= PAGE_SHIFT;
 
 	if (unlikely(abs(x) > t)) {
 		node_page_state_add(x, pgdat, item);
@@ -573,6 +575,8 @@ static inline void mod_node_state(struct pglist_data *pgdat,
 		 * for all cpus in a node.
 		 */
 		t = this_cpu_read(pcp->stat_threshold);
+		if (unlikely(item == NR_KERNEL_STACK_KB))
+			t <<= PAGE_SHIFT;
 
 		o = this_cpu_read(*p);
 		n = delta + o;
-- 
2.11.0