mm, slub: retain no free slabs on partial list with CONFIG_SLUB_TINY

SLUB will leave a number of slabs on the partial list even if they are
empty, to avoid some slab freeing and reallocation. The goal of
CONFIG_SLUB_TINY is to minimize memory overhead, so set the limits to 0
for immediate slab page freeing.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christoph Lameter <cl@linux.com>

mm/slub.c

@@ -241,6 +241,7 @@ static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s)
 /* Enable to log cmpxchg failures */
 #undef SLUB_DEBUG_CMPXCHG
 
+#ifndef CONFIG_SLUB_TINY
 /*
  * Minimum number of partial slabs. These will be left on the partial
  * lists even if they are empty. kmem_cache_shrink may reclaim them.
@@ -253,6 +254,10 @@ static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s)
  * sort the partial list by the number of objects in use.
  */
 #define MAX_PARTIAL 10
+#else
+#define MIN_PARTIAL 0
+#define MAX_PARTIAL 0
+#endif
 
 #define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \
 				SLAB_POISON | SLAB_STORE_USER)