patch-2.4.23 linux-2.4.23/include/linux/mmzone.h

• Lines: 80
• Date: 2003-11-28 10:26:21.000000000 -0800
• Orig file: linux-2.4.22/include/linux/mmzone.h
• Orig date: 2002-11-28 15:53:15.000000000 -0800

diff -urN linux-2.4.22/include/linux/mmzone.h linux-2.4.23/include/linux/mmzone.h
@@ -19,6 +19,11 @@
 #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
 #endif
 
+#define ZONE_DMA               0
+#define ZONE_NORMAL            1
+#define ZONE_HIGHMEM           2
+#define MAX_NR_ZONES           3
+
 typedef struct free_area_struct {
 	struct list_head	free_list;
 	unsigned long		*map;
@@ -26,6 +31,11 @@
 
 struct pglist_data;
 
+typedef struct zone_watermarks_s {
+	unsigned long min, low, high;
+} zone_watermarks_t;
+
+
 /*
  * On machines where it is needed (eg PCs) we divide physical memory
  * into multiple physical zones. On a PC we have 3 zones:
@@ -40,8 +50,27 @@
 	 */
 	spinlock_t		lock;
 	unsigned long		free_pages;
-	unsigned long		pages_min, pages_low, pages_high;
-	int			need_balance;
+	/*
+	 * We don't know if the memory that we're going to allocate will be freeable
+	 * or/and it will be released eventually, so to avoid totally wasting several
+	 * GB of ram we must reserve some of the lower zone memory (otherwise we risk
+	 * to run OOM on the lower zones despite there's tons of freeable ram
+	 * on the higher zones).
+	 */
+	zone_watermarks_t       watermarks[MAX_NR_ZONES];
+
+	/*
+	 * The below fields are protected by different locks (or by
+	 * no lock at all like need_balance), so they're longs to
+	 * provide an atomic granularity against each other on
+	 * all architectures.
+	 */
+	unsigned long           need_balance;
+	/* protected by the pagemap_lru_lock */
+	unsigned long           nr_active_pages, nr_inactive_pages;
+	/* protected by the pagecache_lock */
+	unsigned long           nr_cache_pages;
+
 
 	/*
 	 * free areas of different sizes
@@ -90,13 +119,9 @@
 	 */
 	char			*name;
 	unsigned long		size;
+	unsigned long		realsize;
 } zone_t;
 
-#define ZONE_DMA		0
-#define ZONE_NORMAL		1
-#define ZONE_HIGHMEM		2
-#define MAX_NR_ZONES		3
-
 /*
  * One allocation request operates on a zonelist. A zonelist
  * is a list of zones, the first one is the 'goal' of the
@@ -143,8 +168,8 @@
 extern int numnodes;
 extern pg_data_t *pgdat_list;
 
-#define memclass(pgzone, classzone)	(((pgzone)->zone_pgdat == (classzone)->zone_pgdat) \
-			&& ((pgzone) <= (classzone)))
+#define zone_idx(zone)                 ((zone) - (zone)->zone_pgdat->node_zones)
+#define memclass(pgzone, classzone)    (zone_idx(pgzone) <= zone_idx(classzone))
 
 /*
  * The following two are not meant for general usage. They are here as