mm, page_alloc: convert alloc_flags to unsigned

alloc_flags is a bitmask of flags but it is signed which does not
necessarily generate the best code depending on the compiler.  Even
without an impact, it makes more sense that this be unsigned.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 14 insertions, 12 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7f328cfb137d..094587a4ed81 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1525,7 +1525,7 @@ static inline bool free_pages_prezeroed(bool poisoned)
 }
 
 static int prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
-                                                                int alloc_flags)
+                                                        unsigned int alloc_flags)
 {
         int i;
         bool poisoned = true;
@@ -2391,7 +2391,8 @@ static inline void zone_statistics(struct zone *preferred_zone, struct zone *z,
 static inline
 struct page *buffered_rmqueue(struct zone *preferred_zone,
                         struct zone *zone, unsigned int order,
-                        gfp_t gfp_flags, int alloc_flags, int migratetype)
+                        gfp_t gfp_flags, unsigned int alloc_flags,
+                        int migratetype)
 {
         unsigned long flags;
         struct page *page;
@@ -2545,12 +2546,13 @@ static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
  * to check in the allocation paths if no pages are free.
  */
 static bool __zone_watermark_ok(struct zone *z, unsigned int order,
-                        unsigned long mark, int classzone_idx, int alloc_flags,
+                        unsigned long mark, int classzone_idx,
+                        unsigned int alloc_flags,
                         long free_pages)
 {
         long min = mark;
         int o;
-        const int alloc_harder = (alloc_flags & ALLOC_HARDER);
+        const bool alloc_harder = (alloc_flags & ALLOC_HARDER);
 
         /* free_pages may go negative - that's OK */
         free_pages -= (1 << order) - 1;
@@ -2613,7 +2615,7 @@ static bool __zone_watermark_ok(struct zone *z, unsigned int order,
 }
 
 bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
-                      int classzone_idx, int alloc_flags)
+                      int classzone_idx, unsigned int alloc_flags)
 {
         return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
                                         zone_page_state(z, NR_FREE_PAGES));
@@ -2957,7 +2959,7 @@ out:
 /* Try memory compaction for high-order allocations before reclaim */
 static struct page *
 __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
-                int alloc_flags, const struct alloc_context *ac,
+                unsigned int alloc_flags, const struct alloc_context *ac,
                 enum migrate_mode mode, int *contended_compaction,
                 bool *deferred_compaction)
 {
@@ -3013,7 +3015,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
 #else
 static inline struct page *
 __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
-                int alloc_flags, const struct alloc_context *ac,
+                unsigned int alloc_flags, const struct alloc_context *ac,
                 enum migrate_mode mode, int *contended_compaction,
                 bool *deferred_compaction)
 {
@@ -3053,7 +3055,7 @@ __perform_reclaim(gfp_t gfp_mask, unsigned int order,
 /* The really slow allocator path where we enter direct reclaim */
 static inline struct page *
 __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
-                int alloc_flags, const struct alloc_context *ac,
+                unsigned int alloc_flags, const struct alloc_context *ac,
                 unsigned long *did_some_progress)
 {
         struct page *page = NULL;
@@ -3092,10 +3094,10 @@ static void wake_all_kswapds(unsigned int order, const struct alloc_context *ac)
                 wakeup_kswapd(zone, order, zone_idx(ac->preferred_zone));
 }
 
-static inline int
+static inline unsigned int
 gfp_to_alloc_flags(gfp_t gfp_mask)
 {
-        int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
+        unsigned int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
 
         /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
         BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
@@ -3156,7 +3158,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
 {
         bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM;
         struct page *page = NULL;
-        int alloc_flags;
+        unsigned int alloc_flags;
         unsigned long pages_reclaimed = 0;
         unsigned long did_some_progress;
         enum migrate_mode migration_mode = MIGRATE_ASYNC;
@@ -3348,7 +3350,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
         struct zoneref *preferred_zoneref;
         struct page *page = NULL;
         unsigned int cpuset_mems_cookie;
-        int alloc_flags = ALLOC_WMARK_LOW|ALLOC_FAIR;
+        unsigned int alloc_flags = ALLOC_WMARK_LOW|ALLOC_FAIR;
         gfp_t alloc_mask; /* The gfp_t that was actually used for allocation */
         struct alloc_context ac = {
                 .high_zoneidx = gfp_zone(gfp_mask),