[PATCH] memory hotplug locking: zone span seqlock

[thirdparty/kernel/linux.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 32fad6d23200f7333f4635b128b78a4cefe37c79..817635f2ab6216df4110e14efb016ef803faa8b6 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -33,6 +33,7 @@
 #include <linux/sysctl.h>
 #include <linux/cpu.h>
 #include <linux/cpuset.h>
+#include <linux/memory_hotplug.h>
 #include <linux/nodemask.h>
 #include <linux/vmalloc.h>
 
@@ -80,12 +81,19 @@ unsigned long __initdata nr_all_pages;
 
 static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
 {
-       if (page_to_pfn(page) >= zone->zone_start_pfn + zone->spanned_pages)
-               return 1;
-       if (page_to_pfn(page) < zone->zone_start_pfn)
-               return 1;
+       int ret = 0;
+       unsigned seq;
+       unsigned long pfn = page_to_pfn(page);
 
-       return 0;
+       do {
+               seq = zone_span_seqbegin(zone);
+               if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
+                       ret = 1;
+               else if (pfn < zone->zone_start_pfn)
+                       ret = 1;
+       } while (zone_span_seqretry(zone, seq));
+
+       return ret;
 }
 
 static int page_is_consistent(struct zone *zone, struct page *page)
@@ -1980,6 +1988,7 @@ static void __init free_area_init_core(struct pglist_data *pgdat,
                zone->name = zone_names[j];
                spin_lock_init(&zone->lock);
                spin_lock_init(&zone->lru_lock);
+               zone_seqlock_init(zone);
                zone->zone_pgdat = pgdat;
                zone->free_pages = 0;