radix tree test suite: add allocation counts and size to kmem_cache

Add functions to get the number of allocations, and total allocations from
a kmem_cache. Also add a function to get the allocated size and a way to
zero the total allocations.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Liam R. Howlett <[e-mail]>
Tested-by: Yu Zhao <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: David Howells <[e-mail]>
Cc: Davidlohr Bueso <[e-mail]>
Cc: "Matthew Wilcox (Oracle)" <[e-mail]>
Cc: SeongJae Park <[e-mail]>
Cc: Sven Schnelle <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
Cc: Will Deacon <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

tools/testing/radix-tree/linux.c

···
 	void *objs;
 	void (*ctor)(void *);
 	unsigned int non_kernel;
+	unsigned long nr_allocated;
+	unsigned long nr_tallocated;
 };
 
 void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)
···
 	cachep->non_kernel = val;
 }
 
+unsigned long kmem_cache_get_alloc(struct kmem_cache *cachep)
+{
+	return cachep->size * cachep->nr_allocated;
+}
+
+unsigned long kmem_cache_nr_allocated(struct kmem_cache *cachep)
+{
+	return cachep->nr_allocated;
+}
+
+unsigned long kmem_cache_nr_tallocated(struct kmem_cache *cachep)
+{
+	return cachep->nr_tallocated;
+}
+
+void kmem_cache_zero_nr_tallocated(struct kmem_cache *cachep)
+{
+	cachep->nr_tallocated = 0;
+}
+
 void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,
 		int gfp)
-
 {
 	void *p;
 
···
 			memset(p, 0, cachep->size);
 	}
 
+	uatomic_inc(&cachep->nr_allocated);
 	uatomic_inc(&nr_allocated);
+	uatomic_inc(&cachep->nr_tallocated);
 	if (kmalloc_verbose)
 		printf("Allocating %p from slab\n", p);
 	return p;
···
 {
 	assert(objp);
 	uatomic_dec(&nr_allocated);
+	uatomic_dec(&cachep->nr_allocated);
 	if (kmalloc_verbose)
 		printf("Freeing %p to slab\n", objp);
 	pthread_mutex_lock(&cachep->lock);
···
 	ret->size = size;
 	ret->align = align;
 	ret->nr_objs = 0;
+	ret->nr_allocated = 0;
+	ret->nr_tallocated = 0;
 	ret->objs = NULL;
 	ret->ctor = ctor;
 	ret->non_kernel = 0;