lkml.org 
[lkml]   [2013]   [Sep]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/4] slab: introduce helper functions to get/set free object
Date
In the following patches, to get/set free objects from the freelist
is changed so that simple casting doesn't work for it. Therefore,
introduce helper functions.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>

diff --git a/mm/slab.c b/mm/slab.c
index 9d4bad5..a0e49bb 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2545,9 +2545,15 @@ static struct freelist *alloc_slabmgmt(struct kmem_cache *cachep,
return freelist;
}

-static inline unsigned int *slab_freelist(struct page *page)
+static inline unsigned int get_free_obj(struct page *page, unsigned int idx)
{
- return (unsigned int *)(page->freelist);
+ return ((unsigned int *)page->freelist)[idx];
+}
+
+static inline void set_free_obj(struct page *page,
+ unsigned int idx, unsigned int val)
+{
+ ((unsigned int *)(page->freelist))[idx] = val;
}

static void cache_init_objs(struct kmem_cache *cachep,
@@ -2592,7 +2598,7 @@ static void cache_init_objs(struct kmem_cache *cachep,
if (cachep->ctor)
cachep->ctor(objp);
#endif
- slab_freelist(page)[i] = i;
+ set_free_obj(page, i, i);
}
}

@@ -2611,7 +2617,7 @@ static void *slab_get_obj(struct kmem_cache *cachep, struct page *page,
{
void *objp;

- objp = index_to_obj(cachep, page, slab_freelist(page)[page->active]);
+ objp = index_to_obj(cachep, page, get_free_obj(page, page->active));
page->active++;
#if DEBUG
WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);
@@ -2632,7 +2638,7 @@ static void slab_put_obj(struct kmem_cache *cachep, struct page *page,

/* Verify double free bug */
for (i = page->active; i < cachep->num; i++) {
- if (slab_freelist(page)[i] == objnr) {
+ if (get_free_obj(page, i) == objnr) {
printk(KERN_ERR "slab: double free detected in cache "
"'%s', objp %p\n", cachep->name, objp);
BUG();
@@ -2640,7 +2646,7 @@ static void slab_put_obj(struct kmem_cache *cachep, struct page *page,
}
#endif
page->active--;
- slab_freelist(page)[page->active] = objnr;
+ set_free_obj(page, page->active, objnr);
}

/*
@@ -4214,7 +4220,7 @@ static void handle_slab(unsigned long *n, struct kmem_cache *c,

for (j = page->active; j < c->num; j++) {
/* Skip freed item */
- if (slab_freelist(page)[j] == i) {
+ if (get_free_obj(page, j) == i) {
active = false;
break;
}
--
1.7.9.5


\
 
 \ /
  Last update: 2013-09-02 11:01    [W:0.121 / U:0.360 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site