diff options
Diffstat (limited to 'mm/page_cgroup.c')
| -rw-r--r-- | mm/page_cgroup.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c index f0559e0..e910524 100644 --- a/mm/page_cgroup.c +++ b/mm/page_cgroup.c @@ -28,9 +28,16 @@ struct page_cgroup *lookup_page_cgroup(struct page *page) struct page_cgroup *base; base = NODE_DATA(page_to_nid(page))->node_page_cgroup; +#ifdef CONFIG_DEBUG_VM + /* + * The sanity checks the page allocator does upon freeing a + * page can reach here before the page_cgroup arrays are + * allocated when feeding a range of pages to the allocator + * for the first time during bootup or memory hotplug. + */ if (unlikely(!base)) return NULL; - +#endif offset = pfn - NODE_DATA(page_to_nid(page))->node_start_pfn; return base + offset; } @@ -85,9 +92,16 @@ struct page_cgroup *lookup_page_cgroup(struct page *page) { unsigned long pfn = page_to_pfn(page); struct mem_section *section = __pfn_to_section(pfn); - +#ifdef CONFIG_DEBUG_VM + /* + * The sanity checks the page allocator does upon freeing a + * page can reach here before the page_cgroup arrays are + * allocated when feeding a range of pages to the allocator + * for the first time during bootup or memory hotplug. + */ if (!section->page_cgroup) return NULL; +#endif return section->page_cgroup + pfn; } |
