mm: clean up zone flags

Page reclaim tests zone_is_reclaim_dirty(), but the site that actually
sets this state does zone_set_flag(zone, ZONE_TAIL_LRU_DIRTY), sending the
reader through layers indirection just to track down a simple bit.

Remove all zone flag wrappers and just use bitops against zone->flags
directly.  It's just as readable and the lines are barely any longer.

Also rename ZONE_TAIL_LRU_DIRTY to ZONE_DIRTY to match ZONE_WRITEBACK, and
remove the zone_flags_t typedef.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 318df70518509249bb67a8e9811bf20fdf5fc519..48bf12ef6620ccc863c27afc615a2e2e460a6c99 100644 (file)
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -521,13 +521,13 @@ struct zone {
        atomic_long_t           vm_stat[NR_VM_ZONE_STAT_ITEMS];
 } ____cacheline_internodealigned_in_smp;
 
-typedef enum {
+enum zone_flags {
        ZONE_RECLAIM_LOCKED,            /* prevents concurrent reclaim */
        ZONE_OOM_LOCKED,                /* zone is in OOM killer zonelist */
        ZONE_CONGESTED,                 /* zone has many dirty pages backed by
                                         * a congested BDI
                                         */
-       ZONE_TAIL_LRU_DIRTY,            /* reclaim scanning has recently found
+       ZONE_DIRTY,                     /* reclaim scanning has recently found
                                         * many dirty file pages at the tail
                                         * of the LRU.
                                         */
@@ -535,52 +535,7 @@ typedef enum {
                                         * many pages under writeback
                                         */
        ZONE_FAIR_DEPLETED,             /* fair zone policy batch depleted */
-} zone_flags_t;
-
-static inline void zone_set_flag(struct zone *zone, zone_flags_t flag)
-{
-       set_bit(flag, &zone->flags);
-}
-
-static inline int zone_test_and_set_flag(struct zone *zone, zone_flags_t flag)
-{
-       return test_and_set_bit(flag, &zone->flags);
-}
-
-static inline void zone_clear_flag(struct zone *zone, zone_flags_t flag)
-{
-       clear_bit(flag, &zone->flags);
-}
-
-static inline int zone_is_reclaim_congested(const struct zone *zone)
-{
-       return test_bit(ZONE_CONGESTED, &zone->flags);
-}
-
-static inline int zone_is_reclaim_dirty(const struct zone *zone)
-{
-       return test_bit(ZONE_TAIL_LRU_DIRTY, &zone->flags);
-}
-
-static inline int zone_is_reclaim_writeback(const struct zone *zone)
-{
-       return test_bit(ZONE_WRITEBACK, &zone->flags);
-}
-
-static inline int zone_is_reclaim_locked(const struct zone *zone)
-{
-       return test_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
-}
-
-static inline int zone_is_fair_depleted(const struct zone *zone)
-{
-       return test_bit(ZONE_FAIR_DEPLETED, &zone->flags);
-}
-
-static inline int zone_is_oom_locked(const struct zone *zone)
-{
-       return test_bit(ZONE_OOM_LOCKED, &zone->flags);
-}
+};
 
 static inline unsigned long zone_end_pfn(const struct zone *zone)
 {

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 1706cbbdf5f0381aaf81f21f6bc47b1133e2746b..b27714f1b40fbef79c547ebeedcdcb5863a0b49d 100644 (file)
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -631,7 +631,7 @@ long wait_iff_congested(struct zone *zone, int sync, long timeout)
         * of sleeping on the congestion queue
         */
        if (atomic_read(&nr_bdi_congested[sync]) == 0 ||
-                       !zone_is_reclaim_congested(zone)) {
+           !test_bit(ZONE_CONGESTED, &zone->flags)) {
                cond_resched();
 
                /* In case we scheduled, work out time remaining */

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 1e11df8fa7ecaecd274a3d0aaa1fe0aea4bb38ab..bbf405a3a18f5acd8fbe57fabc06c3e5ce973e29 100644 (file)
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -565,7 +565,7 @@ bool oom_zonelist_trylock(struct zonelist *zonelist, gfp_t gfp_mask)
 
        spin_lock(&zone_scan_lock);
        for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask))
-               if (zone_is_oom_locked(zone)) {
+               if (test_bit(ZONE_OOM_LOCKED, &zone->flags)) {
                        ret = false;
                        goto out;
                }
@@ -575,7 +575,7 @@ bool oom_zonelist_trylock(struct zonelist *zonelist, gfp_t gfp_mask)
         * call to oom_zonelist_trylock() doesn't succeed when it shouldn't.
         */
        for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask))
-               zone_set_flag(zone, ZONE_OOM_LOCKED);
+               set_bit(ZONE_OOM_LOCKED, &zone->flags);
 
 out:
        spin_unlock(&zone_scan_lock);
@@ -594,7 +594,7 @@ void oom_zonelist_unlock(struct zonelist *zonelist, gfp_t gfp_mask)
 
        spin_lock(&zone_scan_lock);
        for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask))
-               zone_clear_flag(zone, ZONE_OOM_LOCKED);
+               clear_bit(ZONE_OOM_LOCKED, &zone->flags);
        spin_unlock(&zone_scan_lock);
 }
 

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ae2f8474273cd8cb2d545f55f16c8c8b0709db61..f3769f0fce3cea4237ff5b436b64cf28fbe1ca86 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1614,8 +1614,8 @@ again:
 
        __mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order));
        if (atomic_long_read(&zone->vm_stat[NR_ALLOC_BATCH]) <= 0 &&
-           !zone_is_fair_depleted(zone))
-               zone_set_flag(zone, ZONE_FAIR_DEPLETED);
+           !test_bit(ZONE_FAIR_DEPLETED, &zone->flags))
+               set_bit(ZONE_FAIR_DEPLETED, &zone->flags);
 
        __count_zone_vm_events(PGALLOC, zone, 1 << order);
        zone_statistics(preferred_zone, zone, gfp_flags);
@@ -1935,7 +1935,7 @@ static void reset_alloc_batches(struct zone *preferred_zone)
                mod_zone_page_state(zone, NR_ALLOC_BATCH,
                        high_wmark_pages(zone) - low_wmark_pages(zone) -
                        atomic_long_read(&zone->vm_stat[NR_ALLOC_BATCH]));
-               zone_clear_flag(zone, ZONE_FAIR_DEPLETED);
+               clear_bit(ZONE_FAIR_DEPLETED, &zone->flags);
        } while (zone++ != preferred_zone);
 }
 
@@ -1986,7 +1986,7 @@ zonelist_scan:
                if (alloc_flags & ALLOC_FAIR) {
                        if (!zone_local(preferred_zone, zone))
                                break;
-                       if (zone_is_fair_depleted(zone)) {
+                       if (test_bit(ZONE_FAIR_DEPLETED, &zone->flags)) {
                                nr_fair_skipped++;
                                continue;
                        }

diff --git a/mm/vmscan.c b/mm/vmscan.c
index af72fe8e8d74478769334739647d6b41d09c59ae..06123f20a3269fde64db1d94bb121197db59fdec 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -920,7 +920,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                        /* Case 1 above */
                        if (current_is_kswapd() &&
                            PageReclaim(page) &&
-                           zone_is_reclaim_writeback(zone)) {
+                           test_bit(ZONE_WRITEBACK, &zone->flags)) {
                                nr_immediate++;
                                goto keep_locked;
 
@@ -1002,7 +1002,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                         */
                        if (page_is_file_cache(page) &&
                                        (!current_is_kswapd() ||
-                                        !zone_is_reclaim_dirty(zone))) {
+                                        !test_bit(ZONE_DIRTY, &zone->flags))) {
                                /*
                                 * Immediately reclaim when written back.
                                 * Similar in principal to deactivate_page()
@@ -1563,7 +1563,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
         * are encountered in the nr_immediate check below.
         */
        if (nr_writeback && nr_writeback == nr_taken)
-               zone_set_flag(zone, ZONE_WRITEBACK);
+               set_bit(ZONE_WRITEBACK, &zone->flags);
 
        /*
         * memcg will stall in page writeback so only consider forcibly
@@ -1575,16 +1575,16 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
                 * backed by a congested BDI and wait_iff_congested will stall.
                 */
                if (nr_dirty && nr_dirty == nr_congested)
-                       zone_set_flag(zone, ZONE_CONGESTED);
+                       set_bit(ZONE_CONGESTED, &zone->flags);
 
                /*
                 * If dirty pages are scanned that are not queued for IO, it
                 * implies that flushers are not keeping up. In this case, flag
-                * the zone ZONE_TAIL_LRU_DIRTY and kswapd will start writing
-                * pages from reclaim context.
+                * the zone ZONE_DIRTY and kswapd will start writing pages from
+                * reclaim context.
                 */
                if (nr_unqueued_dirty == nr_taken)
-                       zone_set_flag(zone, ZONE_TAIL_LRU_DIRTY);
+                       set_bit(ZONE_DIRTY, &zone->flags);
 
                /*
                 * If kswapd scans pages marked marked for immediate
@@ -2984,7 +2984,7 @@ static bool kswapd_shrink_zone(struct zone *zone,
        /* Account for the number of pages attempted to reclaim */
        *nr_attempted += sc->nr_to_reclaim;
 
-       zone_clear_flag(zone, ZONE_WRITEBACK);
+       clear_bit(ZONE_WRITEBACK, &zone->flags);
 
        /*
         * If a zone reaches its high watermark, consider it to be no longer
@@ -2994,8 +2994,8 @@ static bool kswapd_shrink_zone(struct zone *zone,
         */
        if (zone_reclaimable(zone) &&
            zone_balanced(zone, testorder, 0, classzone_idx)) {
-               zone_clear_flag(zone, ZONE_CONGESTED);
-               zone_clear_flag(zone, ZONE_TAIL_LRU_DIRTY);
+               clear_bit(ZONE_CONGESTED, &zone->flags);
+               clear_bit(ZONE_DIRTY, &zone->flags);
        }
 
        return sc->nr_scanned >= sc->nr_to_reclaim;
@@ -3086,8 +3086,8 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order,
                                 * If balanced, clear the dirty and congested
                                 * flags
                                 */
-                               zone_clear_flag(zone, ZONE_CONGESTED);
-                               zone_clear_flag(zone, ZONE_TAIL_LRU_DIRTY);
+                               clear_bit(ZONE_CONGESTED, &zone->flags);
+                               clear_bit(ZONE_DIRTY, &zone->flags);
                        }
                }
 
@@ -3714,11 +3714,11 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
        if (node_state(node_id, N_CPU) && node_id != numa_node_id())
                return ZONE_RECLAIM_NOSCAN;
 
-       if (zone_test_and_set_flag(zone, ZONE_RECLAIM_LOCKED))
+       if (test_and_set_bit(ZONE_RECLAIM_LOCKED, &zone->flags))
                return ZONE_RECLAIM_NOSCAN;
 
        ret = __zone_reclaim(zone, gfp_mask, order);
-       zone_clear_flag(zone, ZONE_RECLAIM_LOCKED);
+       clear_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
 
        if (!ret)
                count_vm_event(PGSCAN_ZONE_RECLAIM_FAILED);