mm: rename RECLAIM_SWAP to RECLAIM_UNMAP

The name SWAP implies that we are dealing with anonymous pages only.  In
fact, the original patch that introduced the min_unmapped_ratio logic
was to fix an issue related to file pages.  Rename it to RECLAIM_UNMAP
to match what does.

Historically, commit a6dc60f8975a ("vmscan: rename sc.may_swap to
may_unmap") renamed .may_swap to .may_unmap, leaving RECLAIM_SWAP
behind.  commit 2e2e42598908 ("vmscan,memcg: reintroduce sc->may_swap")
reintroduced .may_swap for memory controller.

Signed-off-by: Zhihui Zhang <zzhsuny@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index c627fa4..19ef01e 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3597,7 +3597,7 @@ int zone_reclaim_mode __read_mostly;
 #define RECLAIM_OFF 0
 #define RECLAIM_ZONE (1<<0)    /* Run shrink_inactive_list on the zone */
 #define RECLAIM_WRITE (1<<1)   /* Writeout pages during reclaim */
-#define RECLAIM_SWAP (1<<2)    /* Swap pages out during reclaim */
+#define RECLAIM_UNMAP (1<<2)   /* Unmap pages during reclaim */
 
 /*
  * Priority for ZONE_RECLAIM. This determines the fraction of pages
@@ -3639,12 +3639,12 @@ static long zone_pagecache_reclaimable(struct zone *zone)
        long delta = 0;
 
        /*
-        * If RECLAIM_SWAP is set, then all file pages are considered
+        * If RECLAIM_UNMAP is set, then all file pages are considered
         * potentially reclaimable. Otherwise, we have to worry about
         * pages like swapcache and zone_unmapped_file_pages() provides
         * a better estimate
         */
-       if (zone_reclaim_mode & RECLAIM_SWAP)
+       if (zone_reclaim_mode & RECLAIM_UNMAP)
                nr_pagecache_reclaimable = zone_page_state(zone, NR_FILE_PAGES);
        else
                nr_pagecache_reclaimable = zone_unmapped_file_pages(zone);
@@ -3675,15 +3675,15 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
                .order = order,
                .priority = ZONE_RECLAIM_PRIORITY,
                .may_writepage = !!(zone_reclaim_mode & RECLAIM_WRITE),
-               .may_unmap = !!(zone_reclaim_mode & RECLAIM_SWAP),
+               .may_unmap = !!(zone_reclaim_mode & RECLAIM_UNMAP),
                .may_swap = 1,
        };
 
        cond_resched();
        /*
-        * We need to be able to allocate from the reserves for RECLAIM_SWAP
+        * We need to be able to allocate from the reserves for RECLAIM_UNMAP
         * and we also need to be able to write out pages for RECLAIM_WRITE
-        * and RECLAIM_SWAP.
+        * and RECLAIM_UNMAP.
         */
        p->flags |= PF_MEMALLOC | PF_SWAPWRITE;
        lockdep_set_current_reclaim_state(gfp_mask);