[PATCH 4/4] mm/slab: move slab merge from slab_common.c to slub.c
From: sxwjean
Date: Mon Nov 20 2023 - 04:20:34 EST
From: Xiongwei Song <xiongwei.song@xxxxxxxxxxxxx>
Since slab allocator has been removed. There is no users about slab
merge except slub. This commit is almost to revert
commit 423c929cbbec ("mm/slab_common: commonize slab merge logic").
Also change all prefix of slab merge related functions, variables and
definitions from "slab/SLAB" to"slub/SLUB".
Signed-off-by: Xiongwei Song <xiongwei.song@xxxxxxxxxxxxx>
---
mm/slab.h | 3 --
mm/slab_common.c | 98 ----------------------------------------------
mm/slub.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 99 insertions(+), 102 deletions(-)
diff --git a/mm/slab.h b/mm/slab.h
index 8d20f8c6269d..cd52e705ce28 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -429,9 +429,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name,
unsigned int calculate_alignment(slab_flags_t flags,
unsigned int align, unsigned int size);
-int slab_unmergeable(struct kmem_cache *s);
-struct kmem_cache *find_mergeable(unsigned size, unsigned align,
- slab_flags_t flags, const char *name, void (*ctor)(void *));
struct kmem_cache *
__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
slab_flags_t flags, void (*ctor)(void *));
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 62eb77fdedf2..6960ae5c35ee 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -45,36 +45,6 @@ static void slab_caches_to_rcu_destroy_workfn(struct work_struct *work);
static DECLARE_WORK(slab_caches_to_rcu_destroy_work,
slab_caches_to_rcu_destroy_workfn);
-/*
- * Set of flags that will prevent slab merging
- */
-#define SLAB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
- SLAB_TRACE | SLAB_TYPESAFE_BY_RCU | SLAB_NOLEAKTRACE | \
- SLAB_FAILSLAB | SLAB_NO_MERGE | kasan_never_merge())
-
-#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | \
- SLAB_CACHE_DMA32 | SLAB_ACCOUNT)
-
-/*
- * Merge control. If this is set then no merging of slab caches will occur.
- */
-static bool slub_nomerge = !IS_ENABLED(CONFIG_SLAB_MERGE_DEFAULT);
-
-static int __init setup_slab_nomerge(char *str)
-{
- slub_nomerge = true;
- return 1;
-}
-
-static int __init setup_slab_merge(char *str)
-{
- slub_nomerge = false;
- return 1;
-}
-
-__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0);
-__setup_param("slub_merge", slub_merge, setup_slab_merge, 0);
-
/*
* Determine the size of a slab object
*/
@@ -130,74 +100,6 @@ unsigned int calculate_alignment(slab_flags_t flags,
return ALIGN(align, sizeof(void *));
}
-/*
- * Find a mergeable slab cache
- */
-int slab_unmergeable(struct kmem_cache *s)
-{
- if (slub_nomerge || (s->flags & SLAB_NEVER_MERGE))
- return 1;
-
- if (s->ctor)
- return 1;
-
-#ifdef CONFIG_HARDENED_USERCOPY
- if (s->usersize)
- return 1;
-#endif
-
- /*
- * We may have set a slab to be unmergeable during bootstrap.
- */
- if (s->refcount < 0)
- return 1;
-
- return 0;
-}
-
-struct kmem_cache *find_mergeable(unsigned int size, unsigned int align,
- slab_flags_t flags, const char *name, void (*ctor)(void *))
-{
- struct kmem_cache *s;
-
- if (slub_nomerge)
- return NULL;
-
- if (ctor)
- return NULL;
-
- size = ALIGN(size, sizeof(void *));
- align = calculate_alignment(flags, align, size);
- size = ALIGN(size, align);
- flags = kmem_cache_flags(size, flags, name);
-
- if (flags & SLAB_NEVER_MERGE)
- return NULL;
-
- list_for_each_entry_reverse(s, &slab_caches, list) {
- if (slab_unmergeable(s))
- continue;
-
- if (size > s->size)
- continue;
-
- if ((flags & SLAB_MERGE_SAME) != (s->flags & SLAB_MERGE_SAME))
- continue;
- /*
- * Check if alignment is compatible.
- * Courtesy of Adrian Drzewiecki
- */
- if ((s->size & ~(align - 1)) != s->size)
- continue;
-
- if (s->size - size >= sizeof(void *))
- continue;
-
- return s;
- }
- return NULL;
-}
-
static struct kmem_cache *create_cache(const char *name,
unsigned int object_size, unsigned int align,
slab_flags_t flags, unsigned int useroffset,
diff --git a/mm/slub.c b/mm/slub.c
index ae1e6e635253..435d9ed140e4 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -709,6 +709,104 @@ static inline bool slab_update_freelist(struct kmem_cache *s, struct slab *slab,
return false;
}
+/*
+ * Set of flags that will prevent slab merging
+ */
+#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
+ SLAB_TRACE | SLAB_TYPESAFE_BY_RCU | SLAB_NOLEAKTRACE | \
+ SLAB_FAILSLAB | SLAB_NO_MERGE | kasan_never_merge())
+
+#define SLUB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | \
+ SLAB_CACHE_DMA32 | SLAB_ACCOUNT)
+
+/*
+ * Merge control. If this is set then no merging of slab caches will occur.
+ */
+static bool slub_nomerge = !IS_ENABLED(CONFIG_SLAB_MERGE_DEFAULT);
+
+static int __init setup_slub_nomerge(char *str)
+{
+ slub_nomerge = true;
+ return 1;
+}
+
+static int __init setup_slub_merge(char *str)
+{
+ slub_nomerge = false;
+ return 1;
+}
+
+__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0);
+__setup_param("slub_merge", slub_merge, setup_slab_merge, 0);
+
+/*
+ * Find a mergeable slab cache
+ */
+static inline int slub_unmergeable(struct kmem_cache *s)
+{
+ if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
+ return 1;
+
+ if (s->ctor)
+ return 1;
+
+#ifdef CONFIG_HARDENED_USERCOPY
+ if (s->usersize)
+ return 1;
+#endif
+
+ /*
+ * We may have set a slab to be unmergeable during bootstrap.
+ */
+ if (s->refcount < 0)
+ return 1;
+
+ return 0;
+}
+
+static struct kmem_cache *find_mergeable(unsigned int size, unsigned int align,
+ slab_flags_t flags, const char *name, void (*ctor)(void *))
+{
+ struct kmem_cache *s;
+
+ if (slub_nomerge)
+ return NULL;
+
+ if (ctor)
+ return NULL;
+
+ size = ALIGN(size, sizeof(void *));
+ align = calculate_alignment(flags, align, size);
+ size = ALIGN(size, align);
+ flags = kmem_cache_flags(size, flags, name);
+
+ if (flags & SLUB_NEVER_MERGE)
+ return NULL;
+
+ list_for_each_entry_reverse(s, &slab_caches, list) {
+ if (slub_unmergeable(s))
+ continue;
+
+ if (size > s->size)
+ continue;
+
+ if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
+ continue;
+ /*
+ * Check if alignment is compatible.
+ * Courtesy of Adrian Drzewiecki
+ */
+ if ((s->size & ~(align - 1)) != s->size)
+ continue;
+
+ if (s->size - size >= sizeof(void *))
+ continue;
+
+ return s;
+ }
+ return NULL;
+}
+
#ifdef CONFIG_SLUB_DEBUG
static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)];
static DEFINE_SPINLOCK(object_map_lock);
@@ -6679,7 +6777,7 @@ static int sysfs_slab_add(struct kmem_cache *s)
int err;
const char *name;
struct kset *kset = cache_kset(s);
- int unmergeable = slab_unmergeable(s);
+ int unmergeable = slub_unmergeable(s);
if (!unmergeable && disable_higher_order_debug &&
(slub_debug & DEBUG_METADATA_FLAGS))
--
2.34.1