summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
Diffstat (limited to 'mm')
-rw-r--r--mm/Kconfig16
-rw-r--r--mm/kfence/kfence_test.c7
-rw-r--r--mm/slab.c29
-rw-r--r--mm/slab.h5
-rw-r--r--mm/slab_common.c25
5 files changed, 39 insertions, 43 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index 041f0da42f2b..956fb36015c6 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -218,10 +218,17 @@ choice
help
This option allows to select a slab allocator.
-config SLAB
- bool "SLAB"
+config SLAB_DEPRECATED
+ bool "SLAB (DEPRECATED)"
depends on !PREEMPT_RT
help
+ Deprecated and scheduled for removal in a few cycles. Replaced by
+ SLUB.
+
+ If you cannot migrate to SLUB, please contact linux-mm@kvack.org
+ and the people listed in the SLAB ALLOCATOR section of MAINTAINERS
+ file, explaining why.
+
The regular slab allocator that is established and known to work
well in all environments. It organizes cache hot objects in
per cpu and per node queues.
@@ -238,6 +245,11 @@ config SLUB
endchoice
+config SLAB
+ bool
+ default y
+ depends on SLAB_DEPRECATED
+
config SLUB_TINY
bool "Configure SLUB for minimal memory footprint"
depends on SLUB && EXPERT
diff --git a/mm/kfence/kfence_test.c b/mm/kfence/kfence_test.c
index 6aee19a79236..9e008a336d9f 100644
--- a/mm/kfence/kfence_test.c
+++ b/mm/kfence/kfence_test.c
@@ -191,11 +191,10 @@ static size_t setup_test_cache(struct kunit *test, size_t size, slab_flags_t fla
kunit_info(test, "%s: size=%zu, ctor=%ps\n", __func__, size, ctor);
/*
- * Use SLAB_NOLEAKTRACE to prevent merging with existing caches. Any
- * other flag in SLAB_NEVER_MERGE also works. Use SLAB_ACCOUNT to
- * allocate via memcg, if enabled.
+ * Use SLAB_NO_MERGE to prevent merging with existing caches.
+ * Use SLAB_ACCOUNT to allocate via memcg, if enabled.
*/
- flags |= SLAB_NOLEAKTRACE | SLAB_ACCOUNT;
+ flags |= SLAB_NO_MERGE | SLAB_ACCOUNT;
test_cache = kmem_cache_create("test", size, 1, flags, ctor);
KUNIT_ASSERT_TRUE_MSG(test, test_cache, "could not create cache");
diff --git a/mm/slab.c b/mm/slab.c
index 30d241908739..f7dc178b9058 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2355,44 +2355,34 @@ static void cache_init_objs_debug(struct kmem_cache *cachep, struct slab *slab)
#ifdef CONFIG_SLAB_FREELIST_RANDOM
/* Hold information during a freelist initialization */
-union freelist_init_state {
- struct {
- unsigned int pos;
- unsigned int *list;
- unsigned int count;
- };
- struct rnd_state rnd_state;
+struct freelist_init_state {
+ unsigned int pos;
+ unsigned int *list;
+ unsigned int count;
};
/*
* Initialize the state based on the randomization method available.
* return true if the pre-computed list is available, false otherwise.
*/
-static bool freelist_state_initialize(union freelist_init_state *state,
+static bool freelist_state_initialize(struct freelist_init_state *state,
struct kmem_cache *cachep,
unsigned int count)
{
bool ret;
- unsigned int rand;
-
- /* Use best entropy available to define a random shift */
- rand = get_random_u32();
-
- /* Use a random state if the pre-computed list is not available */
if (!cachep->random_seq) {
- prandom_seed_state(&state->rnd_state, rand);
ret = false;
} else {
state->list = cachep->random_seq;
state->count = count;
- state->pos = rand % count;
+ state->pos = get_random_u32_below(count);
ret = true;
}
return ret;
}
/* Get the next entry on the list and randomize it using a random shift */
-static freelist_idx_t next_random_slot(union freelist_init_state *state)
+static freelist_idx_t next_random_slot(struct freelist_init_state *state)
{
if (state->pos >= state->count)
state->pos = 0;
@@ -2413,7 +2403,7 @@ static void swap_free_obj(struct slab *slab, unsigned int a, unsigned int b)
static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab)
{
unsigned int objfreelist = 0, i, rand, count = cachep->num;
- union freelist_init_state state;
+ struct freelist_init_state state;
bool precomputed;
if (count < 2)
@@ -2442,8 +2432,7 @@ static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab)
/* Fisher-Yates shuffle */
for (i = count - 1; i > 0; i--) {
- rand = prandom_u32_state(&state.rnd_state);
- rand %= (i + 1);
+ rand = get_random_u32_below(i + 1);
swap_free_obj(slab, i, rand);
}
} else {
diff --git a/mm/slab.h b/mm/slab.h
index ae41c0c50ba6..ad8f6af3a22f 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -294,11 +294,11 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s)
#if defined(CONFIG_SLAB)
#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
- SLAB_ACCOUNT)
+ SLAB_ACCOUNT | SLAB_NO_MERGE)
#elif defined(CONFIG_SLUB)
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
SLAB_TEMPORARY | SLAB_ACCOUNT | \
- SLAB_NO_USER_FLAGS | SLAB_KMALLOC)
+ SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE)
#else
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE)
#endif
@@ -319,6 +319,7 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s)
SLAB_TEMPORARY | \
SLAB_ACCOUNT | \
SLAB_KMALLOC | \
+ SLAB_NO_MERGE | \
SLAB_NO_USER_FLAGS)
bool __kmem_cache_empty(struct kmem_cache *);
diff --git a/mm/slab_common.c b/mm/slab_common.c
index f6fe35105774..90ecaface410 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -47,7 +47,7 @@ static DECLARE_WORK(slab_caches_to_rcu_destroy_work,
*/
#define SLAB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
SLAB_TRACE | SLAB_TYPESAFE_BY_RCU | SLAB_NOLEAKTRACE | \
- SLAB_FAILSLAB | kasan_never_merge())
+ SLAB_FAILSLAB | SLAB_NO_MERGE | kasan_never_merge())
#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | \
SLAB_CACHE_DMA32 | SLAB_ACCOUNT)
@@ -876,17 +876,17 @@ new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags)
flags |= SLAB_CACHE_DMA;
}
- kmalloc_caches[type][idx] = create_kmalloc_cache(
- kmalloc_info[idx].name[type],
- kmalloc_info[idx].size, flags, 0,
- kmalloc_info[idx].size);
-
/*
* If CONFIG_MEMCG_KMEM is enabled, disable cache merging for
* KMALLOC_NORMAL caches.
*/
if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_NORMAL))
- kmalloc_caches[type][idx]->refcount = -1;
+ flags |= SLAB_NO_MERGE;
+
+ kmalloc_caches[type][idx] = create_kmalloc_cache(
+ kmalloc_info[idx].name[type],
+ kmalloc_info[idx].size, flags, 0,
+ kmalloc_info[idx].size);
}
/*
@@ -1139,7 +1139,7 @@ EXPORT_SYMBOL(kmalloc_large_node);
#ifdef CONFIG_SLAB_FREELIST_RANDOM
/* Randomize a generic freelist */
-static void freelist_randomize(struct rnd_state *state, unsigned int *list,
+static void freelist_randomize(unsigned int *list,
unsigned int count)
{
unsigned int rand;
@@ -1150,8 +1150,7 @@ static void freelist_randomize(struct rnd_state *state, unsigned int *list,
/* Fisher-Yates shuffle */
for (i = count - 1; i > 0; i--) {
- rand = prandom_u32_state(state);
- rand %= (i + 1);
+ rand = get_random_u32_below(i + 1);
swap(list[i], list[rand]);
}
}
@@ -1160,7 +1159,6 @@ static void freelist_randomize(struct rnd_state *state, unsigned int *list,
int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
gfp_t gfp)
{
- struct rnd_state state;
if (count < 2 || cachep->random_seq)
return 0;
@@ -1169,10 +1167,7 @@ int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
if (!cachep->random_seq)
return -ENOMEM;
- /* Get best entropy at this stage of boot */
- prandom_seed_state(&state, get_random_long());
-
- freelist_randomize(&state, cachep->random_seq, count);
+ freelist_randomize(cachep->random_seq, count);
return 0;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-15 11:26:59 +0000