[PATCH v3 03/15] mm/slab: introduce slab_alloc_context

[Vlastimil Babka (SUSE)]

Similarly to page allocator's struct alloc_context, introduce a helper
struct to hold a part of the allocation arguments. This will allow
reducing the number of parameters in many functions of the
implementation, and extend them easily if needed.

For now, make it hold the caller address and the originally requested
allocation size.

Convert alloc_single_from_new_slab(), __slab_alloc_node() and
___slab_alloc(). No functional change intended.

Link: https://patch.msgid.link/20260610-slab_alloc_flags-v2-4-7190909db118@xxxxxxxxxx
Reviewed-by: Harry Yoo (Oracle) <harry@xxxxxxxxxx>
Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@xxxxxxxxxx>
---
 mm/slub.c | 45 ++++++++++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 8845e15cb152..8a0c5553876e 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -213,6 +213,12 @@ DEFINE_STATIC_KEY_FALSE(slub_debug_enabled);
 static DEFINE_STATIC_KEY_FALSE(strict_numa);
 #endif
 
+/* Structure holding extra parameters for slab allocations */
+struct slab_alloc_context {
+	unsigned long caller_addr;
+	size_t orig_size;
+};
+
 /* Structure holding parameters for get_from_partial() call chain */
 struct partial_context {
 	gfp_t flags;
@@ -3687,7 +3693,8 @@ static inline void init_slab_obj_iter(struct kmem_cache *s, struct slab *slab,
  * and put the slab to the partial (or full) list.
  */
 static void *alloc_single_from_new_slab(struct kmem_cache *s, struct slab *slab,
-					int orig_size, bool allow_spin)
+					const struct slab_alloc_context *ac,
+					bool allow_spin)
 {
 	struct kmem_cache_node *n;
 	struct slab_obj_iter iter;
@@ -3705,7 +3712,7 @@ static void *alloc_single_from_new_slab(struct kmem_cache *s, struct slab *slab,
 	/* alloc_debug_processing() always expects a valid freepointer */
 	set_freepointer(s, object, slab->freelist);
 
-	if (!alloc_debug_processing(s, slab, object, orig_size)) {
+	if (!alloc_debug_processing(s, slab, object, ac->orig_size)) {
 		/*
 		 * It's not really expected that this would fail on a
 		 * freshly allocated slab, but a concurrent memory
@@ -4443,7 +4450,7 @@ static unsigned int alloc_from_new_slab(struct kmem_cache *s, struct slab *slab,
  * slab.
  */
 static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
-			   unsigned long addr, unsigned int orig_size)
+			   const struct slab_alloc_context *ac)
 {
 	bool allow_spin = gfpflags_allow_spinning(gfpflags);
 	void *object;
@@ -4476,7 +4483,7 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 			pc.flags = GFP_NOWAIT | __GFP_THISNODE;
 	}
 
-	pc.orig_size = orig_size;
+	pc.orig_size = ac->orig_size;
 	object = get_from_partial(s, node, &pc);
 	if (object)
 		goto success;
@@ -4496,7 +4503,7 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 	stat(s, ALLOC_SLAB);
 
 	if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) {
-		object = alloc_single_from_new_slab(s, slab, orig_size, allow_spin);
+		object = alloc_single_from_new_slab(s, slab, ac, allow_spin);
 
 		if (likely(object))
 			goto success;
@@ -4514,13 +4521,13 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 
 success:
 	if (kmem_cache_debug_flags(s, SLAB_STORE_USER))
-		set_track(s, object, TRACK_ALLOC, addr, gfpflags);
+		set_track(s, object, TRACK_ALLOC, ac->caller_addr, gfpflags);
 
 	return object;
 }
 
 static void *__slab_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node,
-			       unsigned long addr, size_t orig_size)
+			       const struct slab_alloc_context *ac)
 {
 	void *object;
 
@@ -4545,7 +4552,7 @@ static void *__slab_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node,
 	}
 #endif
 
-	object = ___slab_alloc(s, gfpflags, node, addr, orig_size);
+	object = ___slab_alloc(s, gfpflags, node, ac);
 
 	return object;
 }
@@ -4926,8 +4933,13 @@ static __fastpath_inline void *slab_alloc_node(struct kmem_cache *s, struct list
 
 	object = alloc_from_pcs(s, gfpflags, node);
 
-	if (unlikely(!object))
-		object = __slab_alloc_node(s, gfpflags, node, addr, orig_size);
+	if (unlikely(!object)) {
+		const struct slab_alloc_context ac = {
+			.caller_addr = addr,
+			.orig_size = orig_size,
+		};
+		object = __slab_alloc_node(s, gfpflags, node, &ac);
+	}
 
 	maybe_wipe_obj_freeptr(s, object);
 
@@ -5353,6 +5365,10 @@ void *_kmalloc_nolock_noprof(DECL_TOKEN_PARAMS(size, token), gfp_t gfp_flags, in
 	struct kmem_cache *s;
 	bool can_retry = true;
 	void *ret;
+	const struct slab_alloc_context ac = {
+		.caller_addr = _RET_IP_,
+		.orig_size = orig_size,
+	};
 
 	VM_WARN_ON_ONCE(gfp_flags & ~(__GFP_ACCOUNT | __GFP_ZERO |
 				      __GFP_NO_OBJ_EXT));
@@ -5398,7 +5414,7 @@ void *_kmalloc_nolock_noprof(DECL_TOKEN_PARAMS(size, token), gfp_t gfp_flags, in
 	 * kfence_alloc. Hence call __slab_alloc_node() (at most twice)
 	 * and slab_post_alloc_hook() directly.
 	 */
-	ret = __slab_alloc_node(s, alloc_gfp, node, _RET_IP_, orig_size);
+	ret = __slab_alloc_node(s, alloc_gfp, node, &ac);
 
 	/*
 	 * It's possible we failed due to trylock as we preempted someone with
@@ -7240,10 +7256,13 @@ static bool __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags,
 	int i;
 
 	if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) {
+		const struct slab_alloc_context ac = {
+			.caller_addr = _RET_IP_,
+			.orig_size = s->object_size,
+		};
 		for (i = 0; i < size; i++) {
 
-			p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, _RET_IP_,
-					     s->object_size);
+			p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, &ac);
 			if (unlikely(!p[i]))
 				goto error;
 

-- 
2.54.0