[PATCH] Swap Migration V5: Add CONFIG_MIGRATION for page migration support

Include page migration if the system is NUMA or having a memory model that allows distinct areas of memory (SPARSEMEM, DISCONTIGMEM). And: - Only include lru_add_drain_per_cpu if building for an SMP system. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] Swap Migration V5: Add CONFIG_MIGRATION for page migration support
Include page migration if the system is NUMA or having a memory model that allows distinct areas of memory (SPARSEMEM, DISCONTIGMEM). And: - Only include lru_add_drain_per_cpu if building for an SMP system. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Christoph Lameter · Linus Torvalds
1 parent 49d2e9cc45
Showing 3 changed files with 20 additions and 9 deletions Side-by-side Diff
include/linux/swap.h
mm/Kconfig
mm/vmscan.c
@@ -178,7 +178,9 @@
 extern int isolate_lru_page(struct page *p);
 extern int putback_lru_pages(struct list_head *l);
  
+#ifdef CONFIG_MIGRATION
 extern int migrate_pages(struct list_head *l, struct list_head *t);
+#endif
  
 #ifdef CONFIG_MMU
 /* linux/mm/shmem.c */
@@ -132,4 +132,11 @@
 	default "4096" if ARM && !CPU_CACHE_VIPT
 	default "4096" if PARISC && !PA20
 	default "4"
+
+#
+# support for page migration
+#
+config MIGRATION
+	def_bool y if NUMA || SPARSEMEM || DISCONTIGMEM
+	depends on SWAP
@@ -568,6 +568,7 @@
 	return reclaimed;
 }
  
+#ifdef CONFIG_MIGRATION
 /*
  * swapout a single page
  * page is locked upon entry, unlocked on exit
@@ -656,8 +657,9 @@
  
 		/*
 		 * Skip locked pages during the first two passes to give the
-		 * functions holding the lock time to release the page. Later we use
-		 * lock_page to have a higher chance of acquiring the lock.
+		 * functions holding the lock time to release the page. Later we
+		 * use lock_page() to have a higher chance of acquiring the
+		 * lock.
 		 */
 		if (pass > 2)
 			lock_page(page);
  
  
  
@@ -669,15 +671,15 @@
 		 * Only wait on writeback if we have already done a pass where
 		 * we we may have triggered writeouts for lots of pages.
 		 */
-		if (pass > 0)
+		if (pass > 0) {
 			wait_on_page_writeback(page);
-		else
+		} else {
 			if (PageWriteback(page)) {
 				unlock_page(page);
 				goto retry_later;
 			}
+		}
  
-#ifdef CONFIG_SWAP
 		if (PageAnon(page) && !PageSwapCache(page)) {
 			if (!add_to_swap(page)) {
 				unlock_page(page);
  
  
@@ -686,16 +688,15 @@
 				continue;
 			}
 		}
-#endif /* CONFIG_SWAP */
  
 		/*
 		 * Page is properly locked and writeback is complete.
 		 * Try to migrate the page.
 		 */
-		if (swap_page(page)) {
+		if (!swap_page(page))
+			continue;
 retry_later:
-			retry++;
-		}
+		retry++;
 	}
 	if (retry && pass++ < 10)
 		goto redo;
@@ -708,6 +709,7 @@
  
 	return nr_failed + retry;
 }
+#endif
  
 /*
  * zone->lru_lock is heavily contended.  Some of the functions that
...	...	@@ -178,7 +178,9 @@
178	178	extern int isolate_lru_page(struct page *p);
179	179	extern int putback_lru_pages(struct list_head *l);
180	180
	181	+#ifdef CONFIG_MIGRATION
181	182	extern int migrate_pages(struct list_head l, struct list_head t);
	183	+#endif
182	184
183	185	#ifdef CONFIG_MMU
184	186	/* linux/mm/shmem.c */
...	...	@@ -132,4 +132,11 @@
132	132	default "4096" if ARM && !CPU_CACHE_VIPT
133	133	default "4096" if PARISC && !PA20
134	134	default "4"
	135	+
	136	+#
	137	+# support for page migration
	138	+#
	139	+config MIGRATION
	140	+ def_bool y if NUMA \|\| SPARSEMEM \|\| DISCONTIGMEM
	141	+ depends on SWAP
...	...	@@ -568,6 +568,7 @@
568	568	return reclaimed;
569	569	}
570	570
	571	+#ifdef CONFIG_MIGRATION
571	572	/*
572	573	* swapout a single page
573	574	* page is locked upon entry, unlocked on exit
...	...	@@ -656,8 +657,9 @@
656	657
657	658	/*
658	659	* Skip locked pages during the first two passes to give the
659		- * functions holding the lock time to release the page. Later we use
660		- * lock_page to have a higher chance of acquiring the lock.
	660	+ * functions holding the lock time to release the page. Later we
	661	+ * use lock_page() to have a higher chance of acquiring the
	662	+ * lock.
661	663	*/
662	664	if (pass > 2)
663	665	lock_page(page);
664	666
665	667
666	668
...	...	@@ -669,15 +671,15 @@
669	671	* Only wait on writeback if we have already done a pass where
670	672	* we we may have triggered writeouts for lots of pages.
671	673	*/
672		- if (pass > 0)
	674	+ if (pass > 0) {
673	675	wait_on_page_writeback(page);
674		- else
	676	+ } else {
675	677	if (PageWriteback(page)) {
676	678	unlock_page(page);
677	679	goto retry_later;
678	680	}
	681	+ }
679	682
680		-#ifdef CONFIG_SWAP
681	683	if (PageAnon(page) && !PageSwapCache(page)) {
682	684	if (!add_to_swap(page)) {
683	685	unlock_page(page);
684	686
685	687
...	...	@@ -686,16 +688,15 @@
686	688	continue;
687	689	}
688	690	}
689		-#endif /* CONFIG_SWAP */
690	691
691	692	/*
692	693	* Page is properly locked and writeback is complete.
693	694	* Try to migrate the page.
694	695	*/
695		- if (swap_page(page)) {
	696	+ if (!swap_page(page))
	697	+ continue;
696	698	retry_later:
697		- retry++;
698		- }
	699	+ retry++;
699	700	}
700	701	if (retry && pass++ < 10)
701	702	goto redo;
...	...	@@ -708,6 +709,7 @@
708	709
709	710	return nr_failed + retry;
710	711	}
	712	+#endif
711	713
712	714	/*
713	715	* zone->lru_lock is heavily contended. Some of the functions that