lkml.org 
[lkml]   [2019]   [Nov]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
Subject[PATCH v4 1/2] mm: clean up validate_slab()
From
The function doesn't need to return any value, and the check can be
done in one pass.

There is a behavior change: before the patch, we stop at the first
invalid free object; after the patch, we stop at the first invalid
object, free or in use. This shouldn't matter because the original
behavior isn't intended anyway.

Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Yu Zhao <yuzhao@google.com>
---
mm/slub.c | 21 ++++++++-------------
1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index b25c807a111f..6930c3febad7 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4404,31 +4404,26 @@ static int count_total(struct page *page)
#endif

#ifdef CONFIG_SLUB_DEBUG
-static int validate_slab(struct kmem_cache *s, struct page *page,
+static void validate_slab(struct kmem_cache *s, struct page *page,
unsigned long *map)
{
void *p;
void *addr = page_address(page);

- if (!check_slab(s, page) ||
- !on_freelist(s, page, NULL))
- return 0;
+ if (!check_slab(s, page) || !on_freelist(s, page, NULL))
+ return;

/* Now we know that a valid freelist exists */
bitmap_zero(map, page->objects);

get_map(s, page, map);
for_each_object(p, s, addr, page->objects) {
- if (test_bit(slab_index(p, s, addr), map))
- if (!check_object(s, page, p, SLUB_RED_INACTIVE))
- return 0;
- }
+ u8 val = test_bit(slab_index(p, s, addr), map) ?
+ SLUB_RED_INACTIVE : SLUB_RED_ACTIVE;

- for_each_object(p, s, addr, page->objects)
- if (!test_bit(slab_index(p, s, addr), map))
- if (!check_object(s, page, p, SLUB_RED_ACTIVE))
- return 0;
- return 1;
+ if (!check_object(s, page, p, val))
+ break;
+ }
}

static void validate_slab_slab(struct kmem_cache *s, struct page *page,
--
2.24.0.rc1.363.gb1bccd3e3d-goog
\
 
 \ /
  Last update: 2019-11-08 20:41    [W:0.118 / U:9.656 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site