[PATCH v2 18/23] mm/sl[au]b: generalize kmalloc subsystem

[Hyeonggon Yoo]

Now everything in kmalloc subsystem can be generalized.
Let's do it!

Generalize __kmalloc_node_track_caller(), kfree(), __ksize(),
__kmalloc_node() and move them to slab_common.c.

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
---
 mm/slab.c        | 94 -----------------------------------------------
 mm/slab_common.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++
 mm/slub.c        | 88 --------------------------------------------
 3 files changed, 95 insertions(+), 182 deletions(-)

diff --git a/mm/slab.c b/mm/slab.c
index d35873da5572..fc00aca62ae3 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3527,36 +3527,6 @@ void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
 EXPORT_SYMBOL(kmem_cache_alloc_node_trace);
 #endif
 
-static __always_inline void *
-__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller)
-{
-	struct kmem_cache *cachep;
-	void *ret;
-
-	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
-		return kmalloc_large_node(size, flags, node);
-	cachep = kmalloc_slab(size, flags);
-	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
-		return cachep;
-	ret = kmem_cache_alloc_node_trace(cachep, flags, node, size);
-	ret = kasan_kmalloc(cachep, ret, size, flags);
-
-	return ret;
-}
-
-void *__kmalloc_node(size_t size, gfp_t flags, int node)
-{
-	return __do_kmalloc_node(size, flags, node, _RET_IP_);
-}
-EXPORT_SYMBOL(__kmalloc_node);
-
-void *__kmalloc_node_track_caller(size_t size, gfp_t flags,
-		int node, unsigned long caller)
-{
-	return __do_kmalloc_node(size, flags, node, caller);
-}
-EXPORT_SYMBOL(__kmalloc_node_track_caller);
-
 #ifdef CONFIG_PRINTK
 void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab)
 {
@@ -3635,43 +3605,6 @@ void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p)
 }
 EXPORT_SYMBOL(kmem_cache_free_bulk);
 
-/**
- * kfree - free previously allocated memory
- * @objp: pointer returned by kmalloc.
- *
- * If @objp is NULL, no operation is performed.
- *
- * Don't free memory not originally allocated by kmalloc()
- * or you will run into trouble.
- */
-void kfree(const void *objp)
-{
-	struct kmem_cache *c;
-	unsigned long flags;
-	struct folio *folio;
-
-
-	if (unlikely(ZERO_OR_NULL_PTR(objp)))
-		return;
-
-	folio = virt_to_folio(objp);
-	if (!folio_test_slab(folio)) {
-		free_large_kmalloc(folio, (void *)objp);
-		return;
-	}
-
-	c = folio_slab(folio)->slab_cache;
-	trace_kmem_cache_free(c->name, _RET_IP_, objp);
-
-	local_irq_save(flags);
-	kfree_debugcheck(objp);
-	debug_check_no_locks_freed(objp, c->object_size);
-	debug_check_no_obj_freed(objp, c->object_size);
-	__cache_free(c, (void *)objp, _RET_IP_);
-	local_irq_restore(flags);
-}
-EXPORT_SYMBOL(kfree);
-
 /*
  * This initializes kmem_cache_node or resizes various caches for all nodes.
  */
@@ -4074,30 +4007,3 @@ void __check_heap_object(const void *ptr, unsigned long n,
 	usercopy_abort("SLAB object", cachep->name, to_user, offset, n);
 }
 #endif /* CONFIG_HARDENED_USERCOPY */
-
-/**
- * __ksize -- Uninstrumented ksize.
- * @objp: pointer to the object
- *
- * Unlike ksize(), __ksize() is uninstrumented, and does not provide the same
- * safety checks as ksize() with KASAN instrumentation enabled.
- *
- * Return: size of the actual memory used by @objp in bytes
- */
-size_t __ksize(const void *objp)
-{
-	struct kmem_cache *c;
-	struct folio *folio;
-
-	BUG_ON(!objp);
-	if (unlikely(objp == ZERO_SIZE_PTR))
-		return 0;
-
-	folio = virt_to_folio(objp);
-	if (!folio_test_slab(folio))
-		return folio_size(folio);
-
-	c = folio_slab(folio)->slab_cache;
-	return c->object_size;
-}
-EXPORT_SYMBOL(__ksize);
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 3cd5d7a47ec7..daf626e25e12 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -918,6 +918,101 @@ void free_large_kmalloc(struct folio *folio, void *object)
 			      -(PAGE_SIZE << order));
 	__free_pages(folio_page(folio, 0), order);
 }
+
+void *__kmalloc_node(size_t size, gfp_t flags, int node)
+{
+	struct kmem_cache *s;
+	void *ret;
+
+	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
+		return kmalloc_large_node(size, flags, node);
+
+	s = kmalloc_slab(size, flags);
+
+	if (unlikely(ZERO_OR_NULL_PTR(s)))
+		return s;
+
+	ret = __kmem_cache_alloc_node(s, NULL, flags, node, _RET_IP_);
+	ret = kasan_kmalloc(s, ret, size, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(__kmalloc_node);
+
+void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
+					int node, unsigned long caller)
+{
+	struct kmem_cache *s;
+	void *ret;
+
+	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
+		return kmalloc_large_node(size, gfpflags, node);
+
+	s = kmalloc_slab(size, gfpflags);
+
+	if (unlikely(ZERO_OR_NULL_PTR(s)))
+		return s;
+
+	ret = __kmem_cache_alloc_node(s, NULL, gfpflags, node, caller);
+
+	return ret;
+}
+EXPORT_SYMBOL(__kmalloc_node_track_caller);
+
+/**
+ * kfree - free previously allocated memory
+ * @objp: pointer returned by kmalloc.
+ *
+ * If @objp is NULL, no operation is performed.
+ *
+ * Don't free memory not originally allocated by kmalloc()
+ * or you will run into trouble.
+ */
+void kfree(const void *object)
+{
+	struct folio *folio;
+	struct slab *slab;
+	struct kmem_cache *s;
+
+	if (unlikely(ZERO_OR_NULL_PTR(object)))
+		return;
+
+	folio = virt_to_folio(object);
+	if (unlikely(!folio_test_slab(folio))) {
+		free_large_kmalloc(folio, (void *)object);
+		return;
+	}
+
+	slab = folio_slab(folio);
+	s = slab->slab_cache;
+	__kmem_cache_free(s, object, _RET_IP_);
+}
+EXPORT_SYMBOL(kfree);
+
+/**
+ * __ksize -- Uninstrumented ksize.
+ * @objp: pointer to the object
+ *
+ * Unlike ksize(), __ksize() is uninstrumented, and does not provide the same
+ * safety checks as ksize() with KASAN instrumentation enabled.
+ *
+ * Return: size of the actual memory used by @objp in bytes
+ */
+size_t __ksize(const void *object)
+{
+	struct folio *folio;
+
+	if (unlikely(object == ZERO_SIZE_PTR))
+		return 0;
+
+	folio = virt_to_folio(object);
+
+	if (unlikely(!folio_test_slab(folio)))
+		return folio_size(folio);
+
+	return slab_ksize(folio_slab(folio)->slab_cache);
+}
+EXPORT_SYMBOL(__ksize);
 #endif /* !CONFIG_SLOB */
 
 gfp_t kmalloc_fix_flags(gfp_t flags)
diff --git a/mm/slub.c b/mm/slub.c
index a72a2d08e793..bc9c96ce0521 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4338,30 +4338,6 @@ static int __init setup_slub_min_objects(char *str)
 
 __setup("slub_min_objects=", setup_slub_min_objects);
 
-void *__kmalloc_node(size_t size, gfp_t flags, int node)
-{
-	struct kmem_cache *s;
-	void *ret;
-
-	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
-		return kmalloc_large_node(size, flags, node);
-
-	s = kmalloc_slab(size, flags);
-
-	if (unlikely(ZERO_OR_NULL_PTR(s)))
-		return s;
-
-	ret = slab_alloc_node(s, NULL, flags, node, _RET_IP_, size);
-
-	trace_kmem_cache_alloc(s->name, _RET_IP_, ret, size,
-			       s->size, flags, node);
-
-	ret = kasan_kmalloc(s, ret, size, flags);
-
-	return ret;
-}
-EXPORT_SYMBOL(__kmalloc_node);
-
 #ifdef CONFIG_HARDENED_USERCOPY
 /*
  * Rejects incorrectly sized objects and objects that are to be copied
@@ -4412,46 +4388,6 @@ void __check_heap_object(const void *ptr, unsigned long n,
 }
 #endif /* CONFIG_HARDENED_USERCOPY */
 
-size_t __ksize(const void *object)
-{
-	struct folio *folio;
-
-	if (unlikely(object == ZERO_SIZE_PTR))
-		return 0;
-
-	folio = virt_to_folio(object);
-
-	if (unlikely(!folio_test_slab(folio)))
-		return folio_size(folio);
-
-	return slab_ksize(folio_slab(folio)->slab_cache);
-}
-EXPORT_SYMBOL(__ksize);
-
-void kfree(const void *x)
-{
-	struct folio *folio;
-	struct slab *slab;
-	void *object = (void *)x;
-	struct kmem_cache *s;
-
-	if (unlikely(ZERO_OR_NULL_PTR(x)))
-		return;
-
-	folio = virt_to_folio(x);
-	if (unlikely(!folio_test_slab(folio))) {
-		free_large_kmalloc(folio, object);
-		return;
-	}
-
-	slab = folio_slab(folio);
-	s = slab->slab_cache;
-
-	trace_kmem_cache_free(s->name, _RET_IP_, x);
-	slab_free(s, slab, object, NULL, 1, _RET_IP_);
-}
-EXPORT_SYMBOL(kfree);
-
 #define SHRINK_PROMOTE_MAX 32
 
 /*
@@ -4799,30 +4735,6 @@ int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags)
 	return 0;
 }
 
-void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
-					int node, unsigned long caller)
-{
-	struct kmem_cache *s;
-	void *ret;
-
-	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
-		return kmalloc_large_node(size, gfpflags, node);
-
-	s = kmalloc_slab(size, gfpflags);
-
-	if (unlikely(ZERO_OR_NULL_PTR(s)))
-		return s;
-
-	ret = slab_alloc_node(s, NULL, gfpflags, node, caller, size);
-
-	/* Honor the call site pointer we received. */
-	trace_kmem_cache_alloc(s->name, caller, ret, size,
-			       s->size, gfpflags, node);
-
-	return ret;
-}
-EXPORT_SYMBOL(__kmalloc_node_track_caller);
-
 #ifdef CONFIG_SYSFS
 static int count_inuse(struct slab *slab)
 {
-- 
2.32.0