mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 12:43:55 +08:00
6f6b895189
If the system had a few memory groups and all of them were destroyed, memcg_limited_groups_array_size has non-zero value, but all new caches are created without memcg_params, because memcg_kmem_enabled() returns false. We try to enumirate child caches in a few places and all of them are potentially dangerous. For example my kernel is compiled with CONFIG_SLAB and it crashed when I tryed to mount a NFS share after a few experiments with kmemcg. BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 IP: [<ffffffff8118166a>] do_tune_cpucache+0x8a/0xd0 PGD b942a067 PUD b999f067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: fscache(+) ip6table_filter ip6_tables iptable_filter ip_tables i2c_piix4 pcspkr virtio_net virtio_balloon i2c_core floppy CPU: 0 PID: 357 Comm: modprobe Not tainted 3.11.0-rc7+ #59 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8800b9f98240 ti: ffff8800ba32e000 task.ti: ffff8800ba32e000 RIP: 0010:[<ffffffff8118166a>] [<ffffffff8118166a>] do_tune_cpucache+0x8a/0xd0 RSP: 0018:ffff8800ba32fb70 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000006 RDX: 0000000000000000 RSI: ffff8800b9f98910 RDI: 0000000000000246 RBP: ffff8800ba32fba0 R08: 0000000000000002 R09: 0000000000000004 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000010 R13: 0000000000000008 R14: 00000000000000d0 R15: ffff8800375d0200 FS: 00007f55f1378740(0000) GS:ffff8800bfa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f24feba57a0 CR3: 0000000037b51000 CR4: 00000000000006f0 Call Trace: enable_cpucache+0x49/0x100 setup_cpu_cache+0x215/0x280 __kmem_cache_create+0x2fa/0x450 kmem_cache_create_memcg+0x214/0x350 kmem_cache_create+0x2b/0x30 fscache_init+0x19b/0x230 [fscache] do_one_initcall+0xfa/0x1b0 load_module+0x1c41/0x26d0 SyS_finit_module+0x86/0xb0 system_call_fastpath+0x16/0x1b Signed-off-by: Andrey Vagin <avagin@openvz.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Glauber Costa <glommer@openvz.org> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
279 lines
7.4 KiB
C
279 lines
7.4 KiB
C
#ifndef MM_SLAB_H
|
|
#define MM_SLAB_H
|
|
/*
|
|
* Internal slab definitions
|
|
*/
|
|
|
|
/*
|
|
* State of the slab allocator.
|
|
*
|
|
* This is used to describe the states of the allocator during bootup.
|
|
* Allocators use this to gradually bootstrap themselves. Most allocators
|
|
* have the problem that the structures used for managing slab caches are
|
|
* allocated from slab caches themselves.
|
|
*/
|
|
enum slab_state {
|
|
DOWN, /* No slab functionality yet */
|
|
PARTIAL, /* SLUB: kmem_cache_node available */
|
|
PARTIAL_ARRAYCACHE, /* SLAB: kmalloc size for arraycache available */
|
|
PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
|
|
UP, /* Slab caches usable but not all extras yet */
|
|
FULL /* Everything is working */
|
|
};
|
|
|
|
extern enum slab_state slab_state;
|
|
|
|
/* The slab cache mutex protects the management structures during changes */
|
|
extern struct mutex slab_mutex;
|
|
|
|
/* The list of all slab caches on the system */
|
|
extern struct list_head slab_caches;
|
|
|
|
/* The slab cache that manages slab cache information */
|
|
extern struct kmem_cache *kmem_cache;
|
|
|
|
unsigned long calculate_alignment(unsigned long flags,
|
|
unsigned long align, unsigned long size);
|
|
|
|
#ifndef CONFIG_SLOB
|
|
/* Kmalloc array related functions */
|
|
void create_kmalloc_caches(unsigned long);
|
|
|
|
/* Find the kmalloc slab corresponding for a certain size */
|
|
struct kmem_cache *kmalloc_slab(size_t, gfp_t);
|
|
#endif
|
|
|
|
|
|
/* Functions provided by the slab allocators */
|
|
extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags);
|
|
|
|
extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size,
|
|
unsigned long flags);
|
|
extern void create_boot_cache(struct kmem_cache *, const char *name,
|
|
size_t size, unsigned long flags);
|
|
|
|
struct mem_cgroup;
|
|
#ifdef CONFIG_SLUB
|
|
struct kmem_cache *
|
|
__kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size,
|
|
size_t align, unsigned long flags, void (*ctor)(void *));
|
|
#else
|
|
static inline struct kmem_cache *
|
|
__kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size,
|
|
size_t align, unsigned long flags, void (*ctor)(void *))
|
|
{ return NULL; }
|
|
#endif
|
|
|
|
|
|
/* Legal flag mask for kmem_cache_create(), for various configurations */
|
|
#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \
|
|
SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS )
|
|
|
|
#if defined(CONFIG_DEBUG_SLAB)
|
|
#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
|
|
#elif defined(CONFIG_SLUB_DEBUG)
|
|
#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
|
|
SLAB_TRACE | SLAB_DEBUG_FREE)
|
|
#else
|
|
#define SLAB_DEBUG_FLAGS (0)
|
|
#endif
|
|
|
|
#if defined(CONFIG_SLAB)
|
|
#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
|
|
SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | SLAB_NOTRACK)
|
|
#elif defined(CONFIG_SLUB)
|
|
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
|
|
SLAB_TEMPORARY | SLAB_NOTRACK)
|
|
#else
|
|
#define SLAB_CACHE_FLAGS (0)
|
|
#endif
|
|
|
|
#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
|
|
|
|
int __kmem_cache_shutdown(struct kmem_cache *);
|
|
|
|
struct seq_file;
|
|
struct file;
|
|
|
|
struct slabinfo {
|
|
unsigned long active_objs;
|
|
unsigned long num_objs;
|
|
unsigned long active_slabs;
|
|
unsigned long num_slabs;
|
|
unsigned long shared_avail;
|
|
unsigned int limit;
|
|
unsigned int batchcount;
|
|
unsigned int shared;
|
|
unsigned int objects_per_slab;
|
|
unsigned int cache_order;
|
|
};
|
|
|
|
void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
|
|
void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
|
|
ssize_t slabinfo_write(struct file *file, const char __user *buffer,
|
|
size_t count, loff_t *ppos);
|
|
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
static inline bool is_root_cache(struct kmem_cache *s)
|
|
{
|
|
return !s->memcg_params || s->memcg_params->is_root_cache;
|
|
}
|
|
|
|
static inline bool cache_match_memcg(struct kmem_cache *cachep,
|
|
struct mem_cgroup *memcg)
|
|
{
|
|
return (is_root_cache(cachep) && !memcg) ||
|
|
(cachep->memcg_params->memcg == memcg);
|
|
}
|
|
|
|
static inline void memcg_bind_pages(struct kmem_cache *s, int order)
|
|
{
|
|
if (!is_root_cache(s))
|
|
atomic_add(1 << order, &s->memcg_params->nr_pages);
|
|
}
|
|
|
|
static inline void memcg_release_pages(struct kmem_cache *s, int order)
|
|
{
|
|
if (is_root_cache(s))
|
|
return;
|
|
|
|
if (atomic_sub_and_test((1 << order), &s->memcg_params->nr_pages))
|
|
mem_cgroup_destroy_cache(s);
|
|
}
|
|
|
|
static inline bool slab_equal_or_root(struct kmem_cache *s,
|
|
struct kmem_cache *p)
|
|
{
|
|
return (p == s) ||
|
|
(s->memcg_params && (p == s->memcg_params->root_cache));
|
|
}
|
|
|
|
/*
|
|
* We use suffixes to the name in memcg because we can't have caches
|
|
* created in the system with the same name. But when we print them
|
|
* locally, better refer to them with the base name
|
|
*/
|
|
static inline const char *cache_name(struct kmem_cache *s)
|
|
{
|
|
if (!is_root_cache(s))
|
|
return s->memcg_params->root_cache->name;
|
|
return s->name;
|
|
}
|
|
|
|
static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
|
|
{
|
|
if (!s->memcg_params)
|
|
return NULL;
|
|
return s->memcg_params->memcg_caches[idx];
|
|
}
|
|
|
|
static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
|
|
{
|
|
if (is_root_cache(s))
|
|
return s;
|
|
return s->memcg_params->root_cache;
|
|
}
|
|
#else
|
|
static inline bool is_root_cache(struct kmem_cache *s)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline bool cache_match_memcg(struct kmem_cache *cachep,
|
|
struct mem_cgroup *memcg)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline void memcg_bind_pages(struct kmem_cache *s, int order)
|
|
{
|
|
}
|
|
|
|
static inline void memcg_release_pages(struct kmem_cache *s, int order)
|
|
{
|
|
}
|
|
|
|
static inline bool slab_equal_or_root(struct kmem_cache *s,
|
|
struct kmem_cache *p)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline const char *cache_name(struct kmem_cache *s)
|
|
{
|
|
return s->name;
|
|
}
|
|
|
|
static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
|
|
{
|
|
return s;
|
|
}
|
|
#endif
|
|
|
|
static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
|
|
{
|
|
struct kmem_cache *cachep;
|
|
struct page *page;
|
|
|
|
/*
|
|
* When kmemcg is not being used, both assignments should return the
|
|
* same value. but we don't want to pay the assignment price in that
|
|
* case. If it is not compiled in, the compiler should be smart enough
|
|
* to not do even the assignment. In that case, slab_equal_or_root
|
|
* will also be a constant.
|
|
*/
|
|
if (!memcg_kmem_enabled() && !unlikely(s->flags & SLAB_DEBUG_FREE))
|
|
return s;
|
|
|
|
page = virt_to_head_page(x);
|
|
cachep = page->slab_cache;
|
|
if (slab_equal_or_root(cachep, s))
|
|
return cachep;
|
|
|
|
pr_err("%s: Wrong slab cache. %s but object is from %s\n",
|
|
__FUNCTION__, cachep->name, s->name);
|
|
WARN_ON_ONCE(1);
|
|
return s;
|
|
}
|
|
#endif
|
|
|
|
|
|
/*
|
|
* The slab lists for all objects.
|
|
*/
|
|
struct kmem_cache_node {
|
|
spinlock_t list_lock;
|
|
|
|
#ifdef CONFIG_SLAB
|
|
struct list_head slabs_partial; /* partial list first, better asm code */
|
|
struct list_head slabs_full;
|
|
struct list_head slabs_free;
|
|
unsigned long free_objects;
|
|
unsigned int free_limit;
|
|
unsigned int colour_next; /* Per-node cache coloring */
|
|
struct array_cache *shared; /* shared per node */
|
|
struct array_cache **alien; /* on other nodes */
|
|
unsigned long next_reap; /* updated without locking */
|
|
int free_touched; /* updated without locking */
|
|
#endif
|
|
|
|
#ifdef CONFIG_SLUB
|
|
unsigned long nr_partial;
|
|
struct list_head partial;
|
|
#ifdef CONFIG_SLUB_DEBUG
|
|
atomic_long_t nr_slabs;
|
|
atomic_long_t total_objects;
|
|
struct list_head full;
|
|
#endif
|
|
#endif
|
|
|
|
};
|
|
|
|
void *slab_next(struct seq_file *m, void *p, loff_t *pos);
|
|
void slab_stop(struct seq_file *m, void *p);
|