mm/vmscan: introduce helper function reclaim_page_list()

Introduce helper function reclaim_page_list() to eliminate the duplicated
code of doing shrink_page_list() and putback_lru_page.  Also we can
separate node reclaim from node page list operation this way.  No
functional change intended.

Link: https://lkml.kernel.org/r/20220425111232.23182-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4ea2380..68d4004 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2536,14 +2536,12 @@ static void shrink_active_list(unsigned long nr_to_scan,
                        nr_deactivate, nr_rotated, sc->priority, file);
 }
 
-unsigned long reclaim_pages(struct list_head *page_list)
+static unsigned int reclaim_page_list(struct list_head *page_list,
+                                     struct pglist_data *pgdat)
 {
-       int nid = NUMA_NO_NODE;
-       unsigned int nr_reclaimed = 0;
-       LIST_HEAD(node_page_list);
        struct reclaim_stat dummy_stat;
-       struct page *page;
-       unsigned int noreclaim_flag;
+       unsigned int nr_reclaimed;
+       struct folio *folio;
        struct scan_control sc = {
                .gfp_mask = GFP_KERNEL,
                .may_writepage = 1,
@@ -2552,6 +2550,24 @@ unsigned long reclaim_pages(struct list_head *page_list)
                .no_demotion = 1,
        };
 
+       nr_reclaimed = shrink_page_list(page_list, pgdat, &sc, &dummy_stat, false);
+       while (!list_empty(page_list)) {
+               folio = lru_to_folio(page_list);
+               list_del(&folio->lru);
+               folio_putback_lru(folio);
+       }
+
+       return nr_reclaimed;
+}
+
+unsigned long reclaim_pages(struct list_head *page_list)
+{
+       int nid = NUMA_NO_NODE;
+       unsigned int nr_reclaimed = 0;
+       LIST_HEAD(node_page_list);
+       struct page *page;
+       unsigned int noreclaim_flag;
+
        noreclaim_flag = memalloc_noreclaim_save();
 
        while (!list_empty(page_list)) {
@@ -2565,28 +2581,12 @@ unsigned long reclaim_pages(struct list_head *page_list)
                        continue;
                }
 
-               nr_reclaimed += shrink_page_list(&node_page_list,
-                                               NODE_DATA(nid),
-                                               &sc, &dummy_stat, false);
-               while (!list_empty(&node_page_list)) {
-                       page = lru_to_page(&node_page_list);
-                       list_del(&page->lru);
-                       putback_lru_page(page);
-               }
-
+               nr_reclaimed += reclaim_page_list(&node_page_list, NODE_DATA(nid));
                nid = NUMA_NO_NODE;
        }
 
-       if (!list_empty(&node_page_list)) {
-               nr_reclaimed += shrink_page_list(&node_page_list,
-                                               NODE_DATA(nid),
-                                               &sc, &dummy_stat, false);
-               while (!list_empty(&node_page_list)) {
-                       page = lru_to_page(&node_page_list);
-                       list_del(&page->lru);
-                       putback_lru_page(page);
-               }
-       }
+       if (!list_empty(&node_page_list))
+               nr_reclaimed += reclaim_page_list(&node_page_list, NODE_DATA(nid));
 
        memalloc_noreclaim_restore(noreclaim_flag);