[RFC,v2,09/10] tools: Add sheafs support to testing infrastructure

Commit Message

Vlastimil Babka Feb. 14, 2025, 4:27 p.m. UTC

From: "Liam R. Howlett" <[e-mail]>

Allocate a sheaf and fill it to the count amount.  Does not fill to the
sheaf limit to detect incorrect allocation requests.

Signed-off-by: Liam R. Howlett <[e-mail]>
---
 tools/include/linux/slab.h   | 24 +++++++++++++
 tools/testing/shared/linux.c | 84 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 108 insertions(+)

Patch

diff --git a/tools/include/linux/slab.h b/tools/include/linux/slab.h
index a475364cfd9fcdb10db252aab18ea3a620326b6b..0b6b42c9921fc402b4f3d4f681a95c9067d128db 100644
--- a/tools/include/linux/slab.h
+++ b/tools/include/linux/slab.h
@@ -22,6 +22,13 @@  enum slab_state {
 	FULL
 };
 
+struct slab_sheaf {
+	struct kmem_cache *cache;
+	unsigned int size;
+	unsigned int capacity;
+	void *objects[];
+};
+
 struct kmem_cache_args {
 	unsigned int align;
 	unsigned int sheaf_capacity;
@@ -79,4 +86,21 @@  void kmem_cache_free_bulk(struct kmem_cache *cachep, size_t size, void **list);
 int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
 			  void **list);
 
+struct slab_sheaf *
+kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size);
+
+void *
+kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf *sheaf);
+
+void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf *sheaf);
+int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf **sheafp, unsigned int size);
+
+static inline unsigned int kmem_cache_sheaf_size(struct slab_sheaf *sheaf)
+{
+	return sheaf->size;
+}
+
 #endif		/* _TOOLS_SLAB_H */
diff --git a/tools/testing/shared/linux.c b/tools/testing/shared/linux.c
index 9f5fd722f27f1d3877be8927be30409cd74ab3c3..a61c755c3c87e80036a5173115e955bfe7d5a80c 100644
--- a/tools/testing/shared/linux.c
+++ b/tools/testing/shared/linux.c
@@ -181,6 +181,12 @@  int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
 	if (kmalloc_verbose)
 		pr_debug("Bulk alloc %lu\n", size);
 
+	if (cachep->exec_callback) {
+		if (cachep->callback)
+			cachep->callback(cachep->private);
+		cachep->exec_callback = false;
+	}
+
 	pthread_mutex_lock(&cachep->lock);
 	if (cachep->nr_objs >= size) {
 		struct radix_tree_node *node;
@@ -270,6 +276,84 @@  __kmem_cache_create_args(const char *name, unsigned int size,
 	return ret;
 }
 
+struct slab_sheaf *
+kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size)
+{
+	struct slab_sheaf *sheaf;
+	unsigned int capacity;
+
+	if (size > s->sheaf_capacity)
+		capacity = size;
+	else
+		capacity = s->sheaf_capacity;
+
+	sheaf = malloc(sizeof(*sheaf) + sizeof(void *) * s->sheaf_capacity * capacity);
+	if (!sheaf) {
+		return NULL;
+	}
+
+	memset(sheaf, 0, size);
+	sheaf->cache = s;
+	sheaf->capacity = capacity;
+	sheaf->size = kmem_cache_alloc_bulk(s, gfp, size, sheaf->objects);
+	if (!sheaf->size) {
+		free(sheaf);
+		return NULL;
+	}
+
+	return sheaf;
+}
+
+int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
+		 struct slab_sheaf **sheafp, unsigned int size)
+{
+	struct slab_sheaf *sheaf = *sheafp;
+	int refill;
+
+	if (sheaf->size >= size)
+		return 0;
+
+	if (size > sheaf->capacity) {
+		sheaf = kmem_cache_prefill_sheaf(s, gfp, size);
+		if (!sheaf)
+			return -ENOMEM;
+
+		kmem_cache_return_sheaf(s, gfp, *sheafp);
+		*sheafp = sheaf;
+		return 0;
+	}
+
+	refill = kmem_cache_alloc_bulk(s, gfp, size - sheaf->size,
+				       &sheaf->objects[sheaf->size]);
+	if (!refill)
+		return -ENOMEM;
+
+	sheaf->size += refill;
+	return 0;
+}
+
+void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
+		 struct slab_sheaf *sheaf)
+{
+	if (sheaf->size) {
+		//s->non_kernel += sheaf->size;
+		kmem_cache_free_bulk(s, sheaf->size, &sheaf->objects[0]);
+	}
+	free(sheaf);
+}
+
+void *
+kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf *sheaf)
+{
+	if (sheaf->size == 0) {
+		printf("Nothing left in sheaf!\n");
+		return NULL;
+	}
+
+	return sheaf->objects[--sheaf->size];
+}
+
 /*
  * Test the test infrastructure for kem_cache_alloc/free and bulk counterparts.
  */