vmscan: Use an indexed array for LRU variables

[linux-2.6-omap-h63xx.git] / include / linux / mmzone.h

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 443bc7cd8c626ca140ce97e3bec258f101f0ff23..156e18f3919b0f9e2132cd6a81dabb35abc38ad1 100644 (file)
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -81,8 +81,9 @@ struct zone_padding {
 enum zone_stat_item {
        /* First 128 byte cacheline (assuming 64 bit words) */
        NR_FREE_PAGES,
-       NR_INACTIVE,
-       NR_ACTIVE,
+       NR_LRU_BASE,
+       NR_INACTIVE = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
+       NR_ACTIVE,      /*  "     "     "   "       "         */
        NR_ANON_PAGES,  /* Mapped anonymous pages */
        NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
                           only modified from process context */
@@ -107,6 +108,19 @@ enum zone_stat_item {
 #endif
        NR_VM_ZONE_STAT_ITEMS };
 
+enum lru_list {
+       LRU_BASE,
+       LRU_INACTIVE=LRU_BASE,  /* must match order of NR_[IN]ACTIVE */
+       LRU_ACTIVE,             /*  "     "     "   "       "        */
+       NR_LRU_LISTS };
+
+#define for_each_lru(l) for (l = 0; l < NR_LRU_LISTS; l++)
+
+static inline int is_active_lru(enum lru_list l)
+{
+       return (l == LRU_ACTIVE);
+}
+
 struct per_cpu_pages {
        int count;              /* number of pages in the list */
        int high;               /* high watermark, emptying needed */
@@ -251,10 +265,10 @@ struct zone {
 
        /* Fields commonly accessed by the page reclaim scanner */
        spinlock_t              lru_lock;       
-       struct list_head        active_list;
-       struct list_head        inactive_list;
-       unsigned long           nr_scan_active;
-       unsigned long           nr_scan_inactive;
+       struct {
+               struct list_head list;
+               unsigned long nr_scan;
+       } lru[NR_LRU_LISTS];
        unsigned long           pages_scanned;     /* since last reclaim */
        unsigned long           flags;             /* zone flags, see below */
 
@@ -751,8 +765,9 @@ static inline int zonelist_node_idx(struct zoneref *zoneref)
  *
  * This function returns the next zone at or below a given zone index that is
  * within the allowed nodemask using a cursor as the starting point for the
- * search. The zoneref returned is a cursor that is used as the next starting
- * point for future calls to next_zones_zonelist().
+ * search. The zoneref returned is a cursor that represents the current zone
+ * being examined. It should be advanced by one before calling
+ * next_zones_zonelist again.
  */
 struct zoneref *next_zones_zonelist(struct zoneref *z,
                                        enum zone_type highest_zoneidx,
@@ -768,9 +783,8 @@ struct zoneref *next_zones_zonelist(struct zoneref *z,
  *
  * This function returns the first zone at or below a given zone index that is
  * within the allowed nodemask. The zoneref returned is a cursor that can be
- * used to iterate the zonelist with next_zones_zonelist. The cursor should
- * not be used by the caller as it does not match the value of the zone
- * returned.
+ * used to iterate the zonelist with next_zones_zonelist by advancing it by
+ * one before calling.
  */
 static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
                                        enum zone_type highest_zoneidx,
@@ -795,7 +809,7 @@ static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
        for (z = first_zones_zonelist(zlist, highidx, nodemask, &zone); \
                zone;                                                   \
-               z = next_zones_zonelist(z, highidx, nodemask, &zone))   \
+               z = next_zones_zonelist(++z, highidx, nodemask, &zone)) \
 
 /**
  * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index