[PATCH] memcg : simplify MEMCG_VMALLOC updates - fix

[Shakeel Butt]

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Signed-off-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
---
 mm/vmalloc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index cdae76994488..bcc90d4357e4 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -3370,6 +3370,7 @@ void vfree(const void *addr)
 
 	if (unlikely(vm->flags & VM_FLUSH_RESET_PERMS))
 		vm_reset_perms(vm);
+	/* All pages of vm should be charged to same memcg, so use first one. */
 	if (vm->nr_pages && !(vm->flags & VM_MAP_PUT_PAGES))
 		mod_memcg_page_state(vm->pages[0], MEMCG_VMALLOC, -vm->nr_pages);
 	for (i = 0; i < vm->nr_pages; i++) {
@@ -3671,6 +3672,7 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 		node, page_order, nr_small_pages, area->pages);
 
 	atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
+	/* All pages of vm should be charged to same memcg, so use first one. */
 	if (gfp_mask & __GFP_ACCOUNT && area->nr_pages)
 		mod_memcg_page_state(area->pages[0], MEMCG_VMALLOC,
 				     area->nr_pages);
-- 
2.47.1