Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[tomoyo/tomoyo-test1.git] / mm / vmstat.c

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 6afc892..a822204 100644 (file)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1383,12 +1383,29 @@ static void pagetypeinfo_showfree_print(struct seq_file *m,
                        unsigned long freecount = 0;
                        struct free_area *area;
                        struct list_head *curr;
+                       bool overflow = false;
 
                        area = &(zone->free_area[order]);
 
-                       list_for_each(curr, &area->free_list[mtype])
-                               freecount++;
-                       seq_printf(m, "%6lu ", freecount);
+                       list_for_each(curr, &area->free_list[mtype]) {
+                               /*
+                                * Cap the free_list iteration because it might
+                                * be really large and we are under a spinlock
+                                * so a long time spent here could trigger a
+                                * hard lockup detector. Anyway this is a
+                                * debugging tool so knowing there is a handful
+                                * of pages of this order should be more than
+                                * sufficient.
+                                */
+                               if (++freecount >= 100000) {
+                                       overflow = true;
+                                       break;
+                               }
+                       }
+                       seq_printf(m, "%s%6lu ", overflow ? ">" : "", freecount);
+                       spin_unlock_irq(&zone->lock);
+                       cond_resched();
+                       spin_lock_irq(&zone->lock);
                }
                seq_putc(m, '\n');
        }
@@ -1972,7 +1989,7 @@ void __init init_mm_internals(void)
 #endif
 #ifdef CONFIG_PROC_FS
        proc_create_seq("buddyinfo", 0444, NULL, &fragmentation_op);
-       proc_create_seq("pagetypeinfo", 0444, NULL, &pagetypeinfo_op);
+       proc_create_seq("pagetypeinfo", 0400, NULL, &pagetypeinfo_op);
        proc_create_seq("vmstat", 0444, NULL, &vmstat_op);
        proc_create_seq("zoneinfo", 0444, NULL, &zoneinfo_op);
 #endif