mm: change isolate mode from #define to bitwise type

commit 4356f21d09283dc6d39a6f7287a65ddab61e2808 upstream.

Stable note: Not tracked in Bugzilla. This patch makes later patches
	easier to apply but has no other impact.

Change ISOLATE_XXX macro with bitwise isolate_mode_t type.  Normally,
macro isn't recommended as it's type-unsafe and making debugging harder as
symbol cannot be passed throught to the debugger.

Quote from Johannes
" Hmm, it would probably be cleaner to fully convert the isolation mode
into independent flags.  INACTIVE, ACTIVE, BOTH is currently a
tri-state among flags, which is a bit ugly."

This patch moves isolate mode from swap.h to mmzone.h by memcontrol.h

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

8 files changed, 43 insertions, 34 deletions

diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
index 12cecc83cd9..4a37c4759cd 100644
--- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
+++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
@@ -379,10 +379,10 @@ EVENT_PROCESS:
 
                         # To closer match vmstat scanning statistics, only count isolate_both
                         # and isolate_inactive as scanning. isolate_active is rotation
-                        # isolate_inactive == 0
-                        # isolate_active   == 1
-                        # isolate_both     == 2
-                        if ($isolate_mode != 1) {
+                        # isolate_inactive == 1
+                        # isolate_active   == 2
+                        # isolate_both     == 3
+                        if ($isolate_mode != 2) {
                                 $perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned;
                         }
                         $perprocesspid{$process_pid}->{HIGH_NR_CONTIG_DIRTY} += $nr_contig_dirty;
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 313a00eca40..4a8da84487b 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -35,7 +35,8 @@ enum mem_cgroup_page_stat_item {
 extern unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
                                         struct list_head *dst,
                                         unsigned long *scanned, int order,
-                                        int mode, struct zone *z,
+                                        isolate_mode_t mode,
+                                        struct zone *z,
                                         struct mem_cgroup *mem_cont,
                                         int active, int file);
 
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index aa2d80b61d4..047ea6521cc 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -158,6 +158,14 @@ static inline int is_unevictable_lru(enum lru_list l)
         return (l == LRU_UNEVICTABLE);
 }
 
+/* Isolate inactive pages */
+#define ISOLATE_INACTIVE        ((__force isolate_mode_t)0x1)
+/* Isolate active pages */
+#define ISOLATE_ACTIVE          ((__force isolate_mode_t)0x2)
+
+/* LRU Isolation modes. */
+typedef unsigned __bitwise__ isolate_mode_t;
+
 enum zone_watermarks {
         WMARK_MIN,
         WMARK_LOW,
diff --git a/include/linux/swap.h b/include/linux/swap.h
index a273468f828..e73799d3b1c 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -243,11 +243,6 @@ static inline void lru_cache_add_file(struct page *page)
         __lru_cache_add(page, LRU_INACTIVE_FILE);
 }
 
-/* LRU Isolation modes. */
-#define ISOLATE_INACTIVE 0      /* Isolate inactive pages. */
-#define ISOLATE_ACTIVE 1        /* Isolate active pages. */
-#define ISOLATE_BOTH 2          /* Isolate both active and inactive pages. */
-
 /* linux/mm/vmscan.c */
 extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
                                         gfp_t gfp_mask, nodemask_t *mask);
@@ -259,7 +254,7 @@ extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
                                                 unsigned int swappiness,
                                                 struct zone *zone,
                                                 unsigned long *nr_scanned);
-extern int __isolate_lru_page(struct page *page, int mode, int file);
+extern int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file);
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 36851f7f13d..edc4b3d25a2 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -266,7 +266,7 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,
                 unsigned long nr_lumpy_taken,
                 unsigned long nr_lumpy_dirty,
                 unsigned long nr_lumpy_failed,
-                int isolate_mode),
+                isolate_mode_t isolate_mode),
 
         TP_ARGS(order, nr_requested, nr_scanned, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, isolate_mode),
 
@@ -278,7 +278,7 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,
                 __field(unsigned long, nr_lumpy_taken)
                 __field(unsigned long, nr_lumpy_dirty)
                 __field(unsigned long, nr_lumpy_failed)
-                __field(int, isolate_mode)
+                __field(isolate_mode_t, isolate_mode)
         ),
 
         TP_fast_assign(
@@ -312,7 +312,7 @@ DEFINE_EVENT(mm_vmscan_lru_isolate_template, mm_vmscan_lru_isolate,
                 unsigned long nr_lumpy_taken,
                 unsigned long nr_lumpy_dirty,
                 unsigned long nr_lumpy_failed,
-                int isolate_mode),
+                isolate_mode_t isolate_mode),
 
         TP_ARGS(order, nr_requested, nr_scanned, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, isolate_mode)
 
@@ -327,7 +327,7 @@ DEFINE_EVENT(mm_vmscan_lru_isolate_template, mm_vmscan_memcg_isolate,
                 unsigned long nr_lumpy_taken,
                 unsigned long nr_lumpy_dirty,
                 unsigned long nr_lumpy_failed,
-                int isolate_mode),
+                isolate_mode_t isolate_mode),
 
         TP_ARGS(order, nr_requested, nr_scanned, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, isolate_mode)
 
diff --git a/mm/compaction.c b/mm/compaction.c
index d6ba0377e26..26521a12f22 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -371,7 +371,8 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
                 }
 
                 /* Try isolate the page */
-                if (__isolate_lru_page(page, ISOLATE_BOTH, 0) != 0)
+                if (__isolate_lru_page(page,
+                                ISOLATE_ACTIVE|ISOLATE_INACTIVE, 0) != 0)
                         continue;
 
                 VM_BUG_ON(PageTransCompound(page));
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ffb99b4e752..57cdf5ad692 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1251,7 +1251,8 @@ mem_cgroup_get_reclaim_stat_from_page(struct page *page)
 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
                                         struct list_head *dst,
                                         unsigned long *scanned, int order,
-                                        int mode, struct zone *z,
+                                        isolate_mode_t mode,
+                                        struct zone *z,
                                         struct mem_cgroup *mem_cont,
                                         int active, int file)
 {
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b146b427cda..9267ba1b664 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1012,23 +1012,27 @@ keep_lumpy:
  *
  * returns 0 on success, -ve errno on failure.
  */
-int __isolate_lru_page(struct page *page, int mode, int file)
+int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file)
 {
+        bool all_lru_mode;
         int ret = -EINVAL;
 
         /* Only take pages on the LRU. */
         if (!PageLRU(page))
                 return ret;
 
+        all_lru_mode = (mode & (ISOLATE_ACTIVE|ISOLATE_INACTIVE)) ==
+                (ISOLATE_ACTIVE|ISOLATE_INACTIVE);
+
         /*
          * When checking the active state, we need to be sure we are
          * dealing with comparible boolean values.  Take the logical not
          * of each.
          */
-        if (mode != ISOLATE_BOTH && (!PageActive(page) != !mode))
+        if (!all_lru_mode && !PageActive(page) != !(mode & ISOLATE_ACTIVE))
                 return ret;
 
-        if (mode != ISOLATE_BOTH && page_is_file_cache(page) != file)
+        if (!all_lru_mode && !!page_is_file_cache(page) != file)
                 return ret;
 
         /*
@@ -1076,7 +1080,8 @@ int __isolate_lru_page(struct page *page, int mode, int file)
  */
 static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
                 struct list_head *src, struct list_head *dst,
-                unsigned long *scanned, int order, int mode, int file)
+                unsigned long *scanned, int order, isolate_mode_t mode,
+                int file)
 {
         unsigned long nr_taken = 0;
         unsigned long nr_lumpy_taken = 0;
@@ -1201,8 +1206,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
 static unsigned long isolate_pages_global(unsigned long nr,
                                         struct list_head *dst,
                                         unsigned long *scanned, int order,
-                                        int mode, struct zone *z,
-                                        int active, int file)
+                                        isolate_mode_t mode,
+                                        struct zone *z, int active, int file)
 {
         int lru = LRU_BASE;
         if (active)
@@ -1448,6 +1453,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
         unsigned long nr_taken;
         unsigned long nr_anon;
         unsigned long nr_file;
+        isolate_mode_t reclaim_mode = ISOLATE_INACTIVE;
 
         while (unlikely(too_many_isolated(zone, file, sc))) {
                 congestion_wait(BLK_RW_ASYNC, HZ/10);
@@ -1458,15 +1464,15 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
         }
 
         set_reclaim_mode(priority, sc, false);
+        if (sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM)
+                reclaim_mode |= ISOLATE_ACTIVE;
+
         lru_add_drain();
         spin_lock_irq(&zone->lru_lock);
 
         if (scanning_global_lru(sc)) {
-                nr_taken = isolate_pages_global(nr_to_scan,
-                        &page_list, &nr_scanned, sc->order,
-                        sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM ?
-                                        ISOLATE_BOTH : ISOLATE_INACTIVE,
-                        zone, 0, file);
+                nr_taken = isolate_pages_global(nr_to_scan, &page_list,
+                        &nr_scanned, sc->order, reclaim_mode, zone, 0, file);
                 zone->pages_scanned += nr_scanned;
                 if (current_is_kswapd())
                         __count_zone_vm_events(PGSCAN_KSWAPD, zone,
@@ -1475,12 +1481,9 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
                         __count_zone_vm_events(PGSCAN_DIRECT, zone,
                                                nr_scanned);
         } else {
-                nr_taken = mem_cgroup_isolate_pages(nr_to_scan,
-                        &page_list, &nr_scanned, sc->order,
-                        sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM ?
-                                        ISOLATE_BOTH : ISOLATE_INACTIVE,
-                        zone, sc->mem_cgroup,
-                        0, file);
+                nr_taken = mem_cgroup_isolate_pages(nr_to_scan, &page_list,
+                        &nr_scanned, sc->order, reclaim_mode, zone,
+                        sc->mem_cgroup, 0, file);
                 /*
                  * mem_cgroup_isolate_pages() keeps track of
                  * scanned pages on its own.