[SLUB] Add debugging for slab defrag

Add some debugging printks for slab defragmentation

Signed-off-by: Christoph Lameter <clameter@sgi.com>

---
 mm/slub.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c	2007-08-08 22:26:58.000000000 -0700
+++ linux-2.6/mm/slub.c	2007-08-08 22:28:16.000000000 -0700
@@ -2591,6 +2591,7 @@ int kmem_cache_isolate_slab(struct page 
 	SetSlabFrozen(page);
 	slab_unlock(page);
 	rc = 0;
+	printk(KERN_ERR "Isolated %s slab=%p objects=%d\n", s->name, page, page->inuse);
 out:
 	local_irq_restore(flags);
 	return rc;
@@ -2661,6 +2662,8 @@ static int kmem_cache_vacate(struct page
 	 */
 	if (page->inuse == objects)
 		ClearSlabReclaimable(page);
+	printk(KERN_ERR "Finish vacate %s slab=%p objects=%d->%d\n",
+		s->name, page, objects, page->inuse);
 out:
 	leftover = page->inuse;
 	unfreeze_slab(s, page, tail);
@@ -2678,6 +2681,7 @@ int kmem_cache_reclaim(struct list_head 
 	void **scratch;
 	struct page *page;
 	struct page *page2;
+	int pages = 0;
 
 	if (list_empty(zaplist))
 		return 0;
@@ -2688,10 +2692,13 @@ int kmem_cache_reclaim(struct list_head 
 
 	list_for_each_entry_safe(page, page2, zaplist, lru) {
 		list_del(&page->lru);
+		pages++;
 		if (kmem_cache_vacate(page, scratch) == 0)
 				freed++;
 	}
 	kfree(scratch);
+	printk(KERN_ERR "kmem_cache_reclaim recovered %d of %d slabs.\n",
+			freed, pages);
 	return freed;
 }