mm: introduce for_each_populated_zone() macro
Impact: cleanup
In almost cases, for_each_zone() is used with populated_zone(). It's
because almost function doesn't need memoryless node information.
Therefore, for_each_populated_zone() can help to make code simplify.
This patch has no functional change.
[akpm@linux-foundation.org: small cleanup]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 1aca6ce..26ef240 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -806,6 +806,14 @@
zone; \
zone = next_zone(zone))
+#define for_each_populated_zone(zone) \
+ for (zone = (first_online_pgdat())->node_zones; \
+ zone; \
+ zone = next_zone(zone)) \
+ if (!populated_zone(zone)) \
+ ; /* do nothing */ \
+ else
+
static inline struct zone *zonelist_zone(struct zoneref *zoneref)
{
return zoneref->zone;
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index f5fc2d7..33e2e4a 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -321,13 +321,10 @@
INIT_LIST_HEAD(list);
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
unsigned long zone_start, zone_end;
struct mem_extent *ext, *cur, *aux;
- if (!populated_zone(zone))
- continue;
-
zone_start = zone->zone_start_pfn;
zone_end = zone->zone_start_pfn + zone->spanned_pages;
@@ -804,8 +801,8 @@
struct zone *zone;
unsigned int cnt = 0;
- for_each_zone(zone)
- if (populated_zone(zone) && is_highmem(zone))
+ for_each_populated_zone(zone)
+ if (is_highmem(zone))
cnt += zone_page_state(zone, NR_FREE_PAGES);
return cnt;
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index a92c914..1ee66364 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -229,17 +229,16 @@
size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES;
tmp = size;
size += highmem_size;
- for_each_zone (zone)
- if (populated_zone(zone)) {
- tmp += snapshot_additional_pages(zone);
- if (is_highmem(zone)) {
- highmem_size -=
+ for_each_populated_zone(zone) {
+ tmp += snapshot_additional_pages(zone);
+ if (is_highmem(zone)) {
+ highmem_size -=
zone_page_state(zone, NR_FREE_PAGES);
- } else {
- tmp -= zone_page_state(zone, NR_FREE_PAGES);
- tmp += zone->lowmem_reserve[ZONE_NORMAL];
- }
+ } else {
+ tmp -= zone_page_state(zone, NR_FREE_PAGES);
+ tmp += zone->lowmem_reserve[ZONE_NORMAL];
}
+ }
if (highmem_size < 0)
highmem_size = 0;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a3803ea..cbd5321 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -922,13 +922,10 @@
unsigned long flags;
struct zone *zone;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
struct per_cpu_pageset *pset;
struct per_cpu_pages *pcp;
- if (!populated_zone(zone))
- continue;
-
pset = zone_pcp(zone, cpu);
pcp = &pset->pcp;
@@ -1879,10 +1876,7 @@
int cpu;
struct zone *zone;
- for_each_zone(zone) {
- if (!populated_zone(zone))
- continue;
-
+ for_each_populated_zone(zone) {
show_node(zone);
printk("%s per-cpu:\n", zone->name);
@@ -1922,12 +1916,9 @@
global_page_state(NR_PAGETABLE),
global_page_state(NR_BOUNCE));
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
int i;
- if (!populated_zone(zone))
- continue;
-
show_node(zone);
printk("%s"
" free:%lukB"
@@ -1967,12 +1958,9 @@
printk("\n");
}
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
unsigned long nr[MAX_ORDER], flags, order, total = 0;
- if (!populated_zone(zone))
- continue;
-
show_node(zone);
printk("%s: ", zone->name);
@@ -2784,11 +2772,7 @@
node_set_state(node, N_CPU); /* this node has a cpu */
- for_each_zone(zone) {
-
- if (!populated_zone(zone))
- continue;
-
+ for_each_populated_zone(zone) {
zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset),
GFP_KERNEL, node);
if (!zone_pcp(zone, cpu))
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 1bca60f..301f057 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2061,11 +2061,9 @@
struct zone *zone;
unsigned long ret = 0;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
enum lru_list l;
- if (!populated_zone(zone))
- continue;
if (zone_is_all_unreclaimable(zone) && prio != DEF_PRIORITY)
continue;
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 8cd81ea..9826766 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -135,11 +135,7 @@
int cpu;
int threshold;
- for_each_zone(zone) {
-
- if (!zone->present_pages)
- continue;
-
+ for_each_populated_zone(zone) {
threshold = calculate_threshold(zone);
for_each_online_cpu(cpu)
@@ -301,12 +297,9 @@
int i;
int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
struct per_cpu_pageset *p;
- if (!populated_zone(zone))
- continue;
-
p = zone_pcp(zone, cpu);
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)