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>

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>
KOSAKI Motohiro · Linus Torvalds
1 parent a6dc60f897
Showing 6 changed files with 27 additions and 48 deletions Side-by-side Diff
include/linux/mmzone.h
kernel/power/snapshot.c
kernel/power/swsusp.c
mm/page_alloc.c
mm/vmscan.c
mm/vmstat.c
@@ -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;
@@ -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;
@@ -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;
@@ -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))
@@ -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;
  
@@ -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)
  
@@ -301,11 +297,8 @@
 	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);
...	...	@@ -806,6 +806,14 @@
806	806	zone; \
807	807	zone = next_zone(zone))
808	808
	809	+#define for_each_populated_zone(zone) \
	810	+ for (zone = (first_online_pgdat())->node_zones; \
	811	+ zone; \
	812	+ zone = next_zone(zone)) \
	813	+ if (!populated_zone(zone)) \
	814	+ ; /* do nothing */ \
	815	+ else
	816	+
809	817	static inline struct zone zonelist_zone(struct zoneref zoneref)
810	818	{
811	819	return zoneref->zone;
...	...	@@ -321,13 +321,10 @@
321	321
322	322	INIT_LIST_HEAD(list);
323	323
324		- for_each_zone(zone) {
	324	+ for_each_populated_zone(zone) {
325	325	unsigned long zone_start, zone_end;
326	326	struct mem_extent ext, cur, *aux;
327	327
328		- if (!populated_zone(zone))
329		- continue;
330		-
331	328	zone_start = zone->zone_start_pfn;
332	329	zone_end = zone->zone_start_pfn + zone->spanned_pages;
333	330
...	...	@@ -804,8 +801,8 @@
804	801	struct zone *zone;
805	802	unsigned int cnt = 0;
806	803
807		- for_each_zone(zone)
808		- if (populated_zone(zone) && is_highmem(zone))
	804	+ for_each_populated_zone(zone)
	805	+ if (is_highmem(zone))
809	806	cnt += zone_page_state(zone, NR_FREE_PAGES);
810	807
811	808	return cnt;
...	...	@@ -229,17 +229,16 @@
229	229	size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES;
230	230	tmp = size;
231	231	size += highmem_size;
232		- for_each_zone (zone)
233		- if (populated_zone(zone)) {
234		- tmp += snapshot_additional_pages(zone);
235		- if (is_highmem(zone)) {
236		- highmem_size -=
	232	+ for_each_populated_zone(zone) {
	233	+ tmp += snapshot_additional_pages(zone);
	234	+ if (is_highmem(zone)) {
	235	+ highmem_size -=
237	236	zone_page_state(zone, NR_FREE_PAGES);
238		- } else {
239		- tmp -= zone_page_state(zone, NR_FREE_PAGES);
240		- tmp += zone->lowmem_reserve[ZONE_NORMAL];
241		- }
	237	+ } else {
	238	+ tmp -= zone_page_state(zone, NR_FREE_PAGES);
	239	+ tmp += zone->lowmem_reserve[ZONE_NORMAL];
242	240	}
	241	+ }
243	242
244	243	if (highmem_size < 0)
245	244	highmem_size = 0;
...	...	@@ -922,13 +922,10 @@
922	922	unsigned long flags;
923	923	struct zone *zone;
924	924
925		- for_each_zone(zone) {
	925	+ for_each_populated_zone(zone) {
926	926	struct per_cpu_pageset *pset;
927	927	struct per_cpu_pages *pcp;
928	928
929		- if (!populated_zone(zone))
930		- continue;
931		-
932	929	pset = zone_pcp(zone, cpu);
933	930
934	931	pcp = &pset->pcp;
...	...	@@ -1879,10 +1876,7 @@
1879	1876	int cpu;
1880	1877	struct zone *zone;
1881	1878
1882		- for_each_zone(zone) {
1883		- if (!populated_zone(zone))
1884		- continue;
1885		-
	1879	+ for_each_populated_zone(zone) {
1886	1880	show_node(zone);
1887	1881	printk("%s per-cpu:\n", zone->name);
1888	1882
1889	1883
...	...	@@ -1922,12 +1916,9 @@
1922	1916	global_page_state(NR_PAGETABLE),
1923	1917	global_page_state(NR_BOUNCE));
1924	1918
1925		- for_each_zone(zone) {
	1919	+ for_each_populated_zone(zone) {
1926	1920	int i;
1927	1921
1928		- if (!populated_zone(zone))
1929		- continue;
1930		-
1931	1922	show_node(zone);
1932	1923	printk("%s"
1933	1924	" free:%lukB"
1934	1925
...	...	@@ -1967,12 +1958,9 @@
1967	1958	printk("\n");
1968	1959	}
1969	1960
1970		- for_each_zone(zone) {
	1961	+ for_each_populated_zone(zone) {
1971	1962	unsigned long nr[MAX_ORDER], flags, order, total = 0;
1972	1963
1973		- if (!populated_zone(zone))
1974		- continue;
1975		-
1976	1964	show_node(zone);
1977	1965	printk("%s: ", zone->name);
1978	1966
...	...	@@ -2784,11 +2772,7 @@
2784	2772
2785	2773	node_set_state(node, N_CPU); /* this node has a cpu */
2786	2774
2787		- for_each_zone(zone) {
2788		-
2789		- if (!populated_zone(zone))
2790		- continue;
2791		-
	2775	+ for_each_populated_zone(zone) {
2792	2776	zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset),
2793	2777	GFP_KERNEL, node);
2794	2778	if (!zone_pcp(zone, cpu))
...	...	@@ -2061,11 +2061,9 @@
2061	2061	struct zone *zone;
2062	2062	unsigned long ret = 0;
2063	2063
2064		- for_each_zone(zone) {
	2064	+ for_each_populated_zone(zone) {
2065	2065	enum lru_list l;
2066	2066
2067		- if (!populated_zone(zone))
2068		- continue;
2069	2067	if (zone_is_all_unreclaimable(zone) && prio != DEF_PRIORITY)
2070	2068	continue;
2071	2069
...	...	@@ -135,11 +135,7 @@
135	135	int cpu;
136	136	int threshold;
137	137
138		- for_each_zone(zone) {
139		-
140		- if (!zone->present_pages)
141		- continue;
142		-
	138	+ for_each_populated_zone(zone) {
143	139	threshold = calculate_threshold(zone);
144	140
145	141	for_each_online_cpu(cpu)
146	142
...	...	@@ -301,11 +297,8 @@
301	297	int i;
302	298	int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
303	299
304		- for_each_zone(zone) {
	300	+ for_each_populated_zone(zone) {
305	301	struct per_cpu_pageset *p;
306		-
307		- if (!populated_zone(zone))
308		- continue;
309	302
310	303	p = zone_pcp(zone, cpu);
311	304