mm: Enable SLUB for RT

Avoid the memory allocation in IRQ section

Signed-off-by: Thomas Gleixner <[email protected]>
[bigeasy: factor out everything except the kcalloc() workaorund ]
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>

Author: KAGA-KOKO

mm/slub.c

@@ -3679,6 +3679,11 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
 							const char *text)
 {
 #ifdef CONFIG_SLUB_DEBUG
+#ifdef CONFIG_PREEMPT_RT_BASE
+	/* XXX move out of irq-off section */
+	slab_err(s, page, text, s->name);
+#else
+
 	void *addr = page_address(page);
 	void *p;
 	unsigned long *map = kcalloc(BITS_TO_LONGS(page->objects),
@@ -3700,6 +3705,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
 	slab_unlock(page);
 	kfree(map);
 #endif
+#endif
 }
 
 /*