diff options
| author | Vlastimil Babka <vbabka@suse.cz> | 2019-07-11 20:55:13 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-12 11:05:43 -0700 |
| commit | 3972f6bb1c6ae1d32dcf2e4ff635d24b77f26dcb (patch) | |
| tree | 24a0c4a24d8e1afdcb7ca5dd088c1bd4d191a9b9 /include/linux/mm.h | |
| parent | 4462b32c9285b521ef378907aa66a5ca485aae41 (diff) | |
mm, debug_pagealloc: use a page type instead of page_ext flag
When debug_pagealloc is enabled, we currently allocate the page_ext
array to mark guard pages with the PAGE_EXT_DEBUG_GUARD flag. Now that
we have the page_type field in struct page, we can use that instead, as
guard pages are neither PageSlab nor mapped to userspace. This reduces
memory overhead when debug_pagealloc is enabled and there are no other
features requiring the page_ext array.
Link: http://lkml.kernel.org/r/20190603143451.27353-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 10 |
1 files changed, 1 insertions, 9 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 2c2e98cae2d1..cb8d413d635e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2862,8 +2862,6 @@ extern long copy_huge_page_from_user(struct page *dst_page, bool allow_pagefault); #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */ -extern struct page_ext_operations debug_guardpage_ops; - #ifdef CONFIG_DEBUG_PAGEALLOC extern unsigned int _debug_guardpage_minorder; DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled); @@ -2880,16 +2878,10 @@ static inline bool debug_guardpage_enabled(void) static inline bool page_is_guard(struct page *page) { - struct page_ext *page_ext; - if (!debug_guardpage_enabled()) return false; - page_ext = lookup_page_ext(page); - if (unlikely(!page_ext)) - return false; - - return test_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags); + return PageGuard(page); } #else static inline unsigned int debug_guardpage_minorder(void) { return 0; } |