This is a preparation patch that copies the GFP flag __GFP_KSWAPD_RECLAIM
into alloc_flags. This is a preparation patch only that avoids having to
pass gfp_mask through a long callchain in a future patch.

Note that the setting in the fast path happens in alloc_flags_nofragment()
and it may be claimed that this has nothing to do with ALLOC_NO_FRAGMENT.
That's true in this patch but is not true later so it's done now for
easier review to show where the flag needs to be recorded.

No functional change.

Signed-off-by: Mel Gorman <mgor...@techsingularity.net>
---
 mm/internal.h   |  1 +
 mm/page_alloc.c | 25 +++++++++++++++++--------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/mm/internal.h b/mm/internal.h
index 544355156c92..be826ee9dc7f 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -489,6 +489,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone 
*zone,
 #else
 #define ALLOC_NOFRAGMENT         0x0
 #endif
+#define ALLOC_KSWAPD           0x200 /* allow waking of kswapd */
 
 enum ttu_flags;
 struct tlbflush_unmap_batch;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4ba84cd2977a..e44eb68744ed 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3278,10 +3278,15 @@ static bool zone_allows_reclaim(struct zone 
*local_zone, struct zone *zone)
  * fragmentation between the Normal and DMA32 zones.
  */
 static inline unsigned int
-alloc_flags_nofragment(struct zone *zone)
+alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask)
 {
+       unsigned int alloc_flags = 0;
+
+       if (gfp_mask & __GFP_KSWAPD_RECLAIM)
+               alloc_flags |= ALLOC_KSWAPD;
+
        if (zone_idx(zone) != ZONE_NORMAL)
-               return 0;
+               goto out;
 
        /*
         * If ZONE_DMA32 exists, assume it is the one after ZONE_NORMAL and
@@ -3290,13 +3295,14 @@ alloc_flags_nofragment(struct zone *zone)
         */
        BUILD_BUG_ON(ZONE_NORMAL - ZONE_DMA32 != 1);
        if (nr_online_nodes > 1 && !populated_zone(--zone))
-               return 0;
+               goto out;
 
-       return ALLOC_NOFRAGMENT;
+out:
+       return alloc_flags;
 }
 #else
 static inline unsigned int
-alloc_flags_nofragment(struct zone *zone)
+alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask)
 {
        return 0;
 }
@@ -3939,6 +3945,9 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
        } else if (unlikely(rt_task(current)) && !in_interrupt())
                alloc_flags |= ALLOC_HARDER;
 
+       if (gfp_mask & __GFP_KSWAPD_RECLAIM)
+               alloc_flags |= ALLOC_KSWAPD;
+
 #ifdef CONFIG_CMA
        if (gfpflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE)
                alloc_flags |= ALLOC_CMA;
@@ -4170,7 +4179,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
        if (!ac->preferred_zoneref->zone)
                goto nopage;
 
-       if (gfp_mask & __GFP_KSWAPD_RECLAIM)
+       if (alloc_flags & ALLOC_KSWAPD)
                wake_all_kswapds(order, gfp_mask, ac);
 
        /*
@@ -4228,7 +4237,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
 
 retry:
        /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */
-       if (gfp_mask & __GFP_KSWAPD_RECLAIM)
+       if (alloc_flags & ALLOC_KSWAPD)
                wake_all_kswapds(order, gfp_mask, ac);
 
        reserve_flags = __gfp_pfmemalloc_flags(gfp_mask);
@@ -4451,7 +4460,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int 
order, int preferred_nid,
         * Forbid the first pass from falling back to types that fragment
         * memory until all local zones are considered.
         */
-       alloc_flags |= alloc_flags_nofragment(ac.preferred_zoneref->zone);
+       alloc_flags |= alloc_flags_nofragment(ac.preferred_zoneref->zone, 
gfp_mask);
 
        /* First allocation attempt */
        page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac);
-- 
2.16.4

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