Display "locked" for an mlocked vma.

Pages in mlocked VMAs are not subject to page migration, so its important
to know if a VMA was mlocked.

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

Index: linux-2.6.16-rc6/mm/mempolicy.c
===================================================================
--- linux-2.6.16-rc6.orig/mm/mempolicy.c	2006-03-11 14:12:55.000000000 -0800
+++ linux-2.6.16-rc6/mm/mempolicy.c	2006-03-17 18:26:05.000000000 -0800
@@ -556,6 +556,16 @@ static void migrate_page_add(struct page
 	}
 }
 
+static int list_count(struct list_head *l)
+{
+	int c = 0;
+	struct list_head *p;
+
+	list_for_each(p, l)
+		c++;
+	return c;
+}
+
 /*
  * Migrate the list 'pagelist' of pages to a certain destination.
  *
@@ -592,8 +602,11 @@ redo:
 					offset + vma->vm_start);
 			offset += PAGE_SIZE;
 		}
-		else
+		else {
 			page = alloc_pages_node(dest, GFP_HIGHUSER, 0);
+			if (page && page_to_nid(page) != dest)
+				printk("Cannot get memory on node %d got memory on %d instead!\n",dest, page_to_nid(page));
+		}
 
 		if (!page) {
 			err = -ENOMEM;
@@ -617,6 +630,8 @@ out:
 		list_del(&page->lru);
 		__free_page(page);
 	}
+	if (!list_empty(&failed) || !list_empty(pagelist))
+		printk(KERN_ERR "migrate_pages_to(%d) busy=%d failed=%d\n", dest, list_count(&failed), list_count(pagelist));
 	list_splice(&failed, pagelist);
 	if (err < 0)
 		return err;
@@ -638,12 +653,14 @@ int migrate_to_node(struct mm_struct *mm
 	LIST_HEAD(pagelist);
 	int err = 0;
 
+	printk(KERN_ERR "migrate_to_node(%p, %d, %d, %x) ",mm, source, dest, flags);
 	nodes_clear(nmask);
 	node_set(source, nmask);
 
 	check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nmask,
 			flags | MPOL_MF_DISCONTIG_OK, &pagelist);
 
+	printk("Candidates=%d\n", list_count(&pagelist));
 	if (!list_empty(&pagelist)) {
 		err = migrate_pages_to(&pagelist, NULL, dest);
 		if (!list_empty(&pagelist))
@@ -666,6 +683,7 @@ int do_migrate_pages(struct mm_struct *m
 	int err = 0;
 	nodemask_t tmp;
 
+	printk(KERN_ERR "do_migrate_ppages(%p, %lx, %lx, %d\n", mm, from_nodes->bits[0], to_nodes->bits[0], flags);
   	down_read(&mm->mmap_sem);
 
 /*
@@ -1758,6 +1776,8 @@ struct numa_maps {
 	unsigned long mapcount_max;
 	unsigned long dirty;
 	unsigned long swapcache;
+	unsigned long min_pagecount;
+	unsigned long max_pagecount;
 	unsigned long node[MAX_NUMNODES];
 };
 
@@ -1785,6 +1805,13 @@ static void gather_stats(struct page *pa
 	if (count > md->mapcount_max)
 		md->mapcount_max = count;
 
+	count = page_count(page);
+	if (count > md->max_pagecount)
+		md->max_pagecount = count;
+
+	if (!md->min_pagecount || count < md->min_pagecount)
+		md->min_pagecount = count;
+
 	md->node[page_to_nid(page)]++;
 	cond_resched();
 }
@@ -1863,9 +1890,13 @@ int show_numa_map(struct seq_file *m, vo
 				&node_online_map, MPOL_MF_STATS, md);
 	}
 
+	if (vma->vm_flags & VM_LOCKED)
+		seq_printf(m, " locked");
+
 	if (!md->pages)
 		goto out;
 
+
 	if (md->anon)
 		seq_printf(m," anon=%lu",md->anon);
 
@@ -1887,6 +1918,9 @@ int show_numa_map(struct seq_file *m, vo
 	if (md->writeback)
 		seq_printf(m," writeback=%lu", md->writeback);
 
+	if (md->min_pagecount > 2 || md->max_pagecount > 1 + md->mapcount_max)
+		seq_printf(m," pc=%lu-%lu", md->min_pagecount, md->max_pagecount);
+
 	for_each_online_node(n)
 		if (md->node[n])
 			seq_printf(m, " N%d=%lu", n, md->node[n]);