[PATCH] SwapMig: CONFIG_MIGRATION fixes
Move move_to_lru, putback_lru_pages and isolate_lru in section surrounded by
CONFIG_MIGRATION saving some codesize for single processor kernels.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 58270ae..daed4a7 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -569,6 +569,40 @@
}
#ifdef CONFIG_MIGRATION
+static inline void move_to_lru(struct page *page)
+{
+ list_del(&page->lru);
+ if (PageActive(page)) {
+ /*
+ * lru_cache_add_active checks that
+ * the PG_active bit is off.
+ */
+ ClearPageActive(page);
+ lru_cache_add_active(page);
+ } else {
+ lru_cache_add(page);
+ }
+ put_page(page);
+}
+
+/*
+ * Add isolated pages on the list back to the LRU
+ *
+ * returns the number of pages put back.
+ */
+int putback_lru_pages(struct list_head *l)
+{
+ struct page *page;
+ struct page *page2;
+ int count = 0;
+
+ list_for_each_entry_safe(page, page2, l, lru) {
+ move_to_lru(page);
+ count++;
+ }
+ return count;
+}
+
/*
* swapout a single page
* page is locked upon entry, unlocked on exit
@@ -709,6 +743,48 @@
return nr_failed + retry;
}
+
+static void lru_add_drain_per_cpu(void *dummy)
+{
+ lru_add_drain();
+}
+
+/*
+ * Isolate one page from the LRU lists and put it on the
+ * indicated list. Do necessary cache draining if the
+ * page is not on the LRU lists yet.
+ *
+ * Result:
+ * 0 = page not on LRU list
+ * 1 = page removed from LRU list and added to the specified list.
+ * -ENOENT = page is being freed elsewhere.
+ */
+int isolate_lru_page(struct page *page)
+{
+ int rc = 0;
+ struct zone *zone = page_zone(page);
+
+redo:
+ spin_lock_irq(&zone->lru_lock);
+ rc = __isolate_lru_page(page);
+ if (rc == 1) {
+ if (PageActive(page))
+ del_page_from_active_list(zone, page);
+ else
+ del_page_from_inactive_list(zone, page);
+ }
+ spin_unlock_irq(&zone->lru_lock);
+ if (rc == 0) {
+ /*
+ * Maybe this page is still waiting for a cpu to drain it
+ * from one of the lru lists?
+ */
+ rc = schedule_on_each_cpu(lru_add_drain_per_cpu, NULL);
+ if (rc == 0 && PageLRU(page))
+ goto redo;
+ }
+ return rc;
+}
#endif
/*
@@ -758,48 +834,6 @@
return nr_taken;
}
-static void lru_add_drain_per_cpu(void *dummy)
-{
- lru_add_drain();
-}
-
-/*
- * Isolate one page from the LRU lists and put it on the
- * indicated list. Do necessary cache draining if the
- * page is not on the LRU lists yet.
- *
- * Result:
- * 0 = page not on LRU list
- * 1 = page removed from LRU list and added to the specified list.
- * -ENOENT = page is being freed elsewhere.
- */
-int isolate_lru_page(struct page *page)
-{
- int rc = 0;
- struct zone *zone = page_zone(page);
-
-redo:
- spin_lock_irq(&zone->lru_lock);
- rc = __isolate_lru_page(page);
- if (rc == 1) {
- if (PageActive(page))
- del_page_from_active_list(zone, page);
- else
- del_page_from_inactive_list(zone, page);
- }
- spin_unlock_irq(&zone->lru_lock);
- if (rc == 0) {
- /*
- * Maybe this page is still waiting for a cpu to drain it
- * from one of the lru lists?
- */
- rc = schedule_on_each_cpu(lru_add_drain_per_cpu, NULL);
- if (rc == 0 && PageLRU(page))
- goto redo;
- }
- return rc;
-}
-
/*
* shrink_cache() adds the number of pages reclaimed to sc->nr_reclaimed
*/
@@ -865,40 +899,6 @@
pagevec_release(&pvec);
}
-static inline void move_to_lru(struct page *page)
-{
- list_del(&page->lru);
- if (PageActive(page)) {
- /*
- * lru_cache_add_active checks that
- * the PG_active bit is off.
- */
- ClearPageActive(page);
- lru_cache_add_active(page);
- } else {
- lru_cache_add(page);
- }
- put_page(page);
-}
-
-/*
- * Add isolated pages on the list back to the LRU
- *
- * returns the number of pages put back.
- */
-int putback_lru_pages(struct list_head *l)
-{
- struct page *page;
- struct page *page2;
- int count = 0;
-
- list_for_each_entry_safe(page, page2, l, lru) {
- move_to_lru(page);
- count++;
- }
- return count;
-}
-
/*
* This moves pages from the active list to the inactive list.
*