mm: simplify code of swap.c
Shaohua Li [Tue, 22 Mar 2011 23:33:45 +0000 (16:33 -0700)]
Clean up code and remove duplicate code. Next patch will use
pagevec_lru_move_fn introduced here too.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hiroyuki Kamezawa <kamezawa.hiroyuki@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/swap.c

index 0a33714..a448db3 100644 (file)
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -179,15 +179,13 @@ void put_pages_list(struct list_head *pages)
 }
 EXPORT_SYMBOL(put_pages_list);
 
-/*
- * pagevec_move_tail() must be called with IRQ disabled.
- * Otherwise this may cause nasty races.
- */
-static void pagevec_move_tail(struct pagevec *pvec)
+static void pagevec_lru_move_fn(struct pagevec *pvec,
+                               void (*move_fn)(struct page *page, void *arg),
+                               void *arg)
 {
        int i;
-       int pgmoved = 0;
        struct zone *zone = NULL;
+       unsigned long flags = 0;
 
        for (i = 0; i < pagevec_count(pvec); i++) {
                struct page *page = pvec->pages[i];
@@ -195,30 +193,50 @@ static void pagevec_move_tail(struct pagevec *pvec)
 
                if (pagezone != zone) {
                        if (zone)
-                               spin_unlock(&zone->lru_lock);
+                               spin_unlock_irqrestore(&zone->lru_lock, flags);
                        zone = pagezone;
-                       spin_lock(&zone->lru_lock);
-               }
-               if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
-                       enum lru_list lru = page_lru_base_type(page);
-                       list_move_tail(&page->lru, &zone->lru[lru].list);
-                       mem_cgroup_rotate_reclaimable_page(page);
-                       pgmoved++;
+                       spin_lock_irqsave(&zone->lru_lock, flags);
                }
+
+               (*move_fn)(page, arg);
        }
        if (zone)
-               spin_unlock(&zone->lru_lock);
-       __count_vm_events(PGROTATED, pgmoved);
+               spin_unlock_irqrestore(&zone->lru_lock, flags);
        release_pages(pvec->pages, pvec->nr, pvec->cold);
        pagevec_reinit(pvec);
 }
 
+static void pagevec_move_tail_fn(struct page *page, void *arg)
+{
+       int *pgmoved = arg;
+       struct zone *zone = page_zone(page);
+
+       if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
+               enum lru_list lru = page_lru_base_type(page);
+               list_move_tail(&page->lru, &zone->lru[lru].list);
+               mem_cgroup_rotate_reclaimable_page(page);
+               (*pgmoved)++;
+       }
+}
+
+/*
+ * pagevec_move_tail() must be called with IRQ disabled.
+ * Otherwise this may cause nasty races.
+ */
+static void pagevec_move_tail(struct pagevec *pvec)
+{
+       int pgmoved = 0;
+
+       pagevec_lru_move_fn(pvec, pagevec_move_tail_fn, &pgmoved);
+       __count_vm_events(PGROTATED, pgmoved);
+}
+
 /*
  * Writeback is about to end against a page which has been marked for immediate
  * reclaim.  If it still appears to be reclaimable, move it to the tail of the
  * inactive list.
  */
-void  rotate_reclaimable_page(struct page *page)
+void rotate_reclaimable_page(struct page *page)
 {
        if (!PageLocked(page) && !PageDirty(page) && !PageActive(page) &&
            !PageUnevictable(page) && PageLRU(page)) {
@@ -369,10 +387,11 @@ void add_page_to_unevictable_list(struct page *page)
  * be write it out by flusher threads as this is much more effective
  * than the single-page writeout from reclaim.
  */
-static void lru_deactivate(struct page *page, struct zone *zone)
+static void lru_deactivate_fn(struct page *page, void *arg)
 {
        int lru, file;
        bool active;
+       struct zone *zone = page_zone(page);
 
        if (!PageLRU(page))
                return;
@@ -412,31 +431,6 @@ static void lru_deactivate(struct page *page, struct zone *zone)
        update_page_reclaim_stat(zone, page, file, 0);
 }
 
-static void ____pagevec_lru_deactivate(struct pagevec *pvec)
-{
-       int i;
-       struct zone *zone = NULL;
-
-       for (i = 0; i < pagevec_count(pvec); i++) {
-               struct page *page = pvec->pages[i];
-               struct zone *pagezone = page_zone(page);
-
-               if (pagezone != zone) {
-                       if (zone)
-                               spin_unlock_irq(&zone->lru_lock);
-                       zone = pagezone;
-                       spin_lock_irq(&zone->lru_lock);
-               }
-               lru_deactivate(page, zone);
-       }
-       if (zone)
-               spin_unlock_irq(&zone->lru_lock);
-
-       release_pages(pvec->pages, pvec->nr, pvec->cold);
-       pagevec_reinit(pvec);
-}
-
-
 /*
  * Drain pages out of the cpu's pagevecs.
  * Either "cpu" is the current CPU, and preemption has already been
@@ -466,7 +460,7 @@ static void drain_cpu_pagevecs(int cpu)
 
        pvec = &per_cpu(lru_deactivate_pvecs, cpu);
        if (pagevec_count(pvec))
-               ____pagevec_lru_deactivate(pvec);
+               pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
 }
 
 /**
@@ -483,7 +477,7 @@ void deactivate_page(struct page *page)
                struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
 
                if (!pagevec_add(pvec, page))
-                       ____pagevec_lru_deactivate(pvec);
+                       pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
                put_cpu_var(lru_deactivate_pvecs);
        }
 }
@@ -630,44 +624,33 @@ void lru_add_page_tail(struct zone* zone,
        }
 }
 
+static void ____pagevec_lru_add_fn(struct page *page, void *arg)
+{
+       enum lru_list lru = (enum lru_list)arg;
+       struct zone *zone = page_zone(page);
+       int file = is_file_lru(lru);
+       int active = is_active_lru(lru);
+
+       VM_BUG_ON(PageActive(page));
+       VM_BUG_ON(PageUnevictable(page));
+       VM_BUG_ON(PageLRU(page));
+
+       SetPageLRU(page);
+       if (active)
+               SetPageActive(page);
+       update_page_reclaim_stat(zone, page, file, active);
+       add_page_to_lru_list(zone, page, lru);
+}
+
 /*
  * Add the passed pages to the LRU, then drop the caller's refcount
  * on them.  Reinitialises the caller's pagevec.
  */
 void ____pagevec_lru_add(struct pagevec *pvec, enum lru_list lru)
 {
-       int i;
-       struct zone *zone = NULL;
-
        VM_BUG_ON(is_unevictable_lru(lru));
 
-       for (i = 0; i < pagevec_count(pvec); i++) {
-               struct page *page = pvec->pages[i];
-               struct zone *pagezone = page_zone(page);
-               int file;
-               int active;
-
-               if (pagezone != zone) {
-                       if (zone)
-                               spin_unlock_irq(&zone->lru_lock);
-                       zone = pagezone;
-                       spin_lock_irq(&zone->lru_lock);
-               }
-               VM_BUG_ON(PageActive(page));
-               VM_BUG_ON(PageUnevictable(page));
-               VM_BUG_ON(PageLRU(page));
-               SetPageLRU(page);
-               active = is_active_lru(lru);
-               file = is_file_lru(lru);
-               if (active)
-                       SetPageActive(page);
-               update_page_reclaim_stat(zone, page, file, active);
-               add_page_to_lru_list(zone, page, lru);
-       }
-       if (zone)
-               spin_unlock_irq(&zone->lru_lock);
-       release_pages(pvec->pages, pvec->nr, pvec->cold);
-       pagevec_reinit(pvec);
+       pagevec_lru_move_fn(pvec, ____pagevec_lru_add_fn, (void *)lru);
 }
 
 EXPORT_SYMBOL(____pagevec_lru_add);