mm, compaction: pass gfp mask to compact_control

struct compact_control currently converts the gfp mask to a migratetype,
but we need the entire gfp mask in a follow-up patch.

Pass the entire gfp mask as part of struct compact_control.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/compaction.c

@@ -1032,8 +1032,8 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
 	return cc->nr_migratepages ? ISOLATE_SUCCESS : ISOLATE_NONE;
 }
 
-static int compact_finished(struct zone *zone,
-			    struct compact_control *cc)
+static int compact_finished(struct zone *zone, struct compact_control *cc,
+			    const int migratetype)
 {
 	unsigned int order;
 	unsigned long watermark;
@@ -1079,7 +1079,7 @@ static int compact_finished(struct zone *zone,
 		struct free_area *area = &zone->free_area[order];
 
 		/* Job done if page is free of the right migratetype */
-		if (!list_empty(&area->free_list[cc->migratetype]))
+		if (!list_empty(&area->free_list[migratetype]))
 			return COMPACT_PARTIAL;
 
 		/* Job done if allocation would set block type */
@@ -1145,6 +1145,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 	int ret;
 	unsigned long start_pfn = zone->zone_start_pfn;
 	unsigned long end_pfn = zone_end_pfn(zone);
+	const int migratetype = gfpflags_to_migratetype(cc->gfp_mask);
 	const bool sync = cc->mode != MIGRATE_ASYNC;
 
 	ret = compaction_suitable(zone, cc->order);
@@ -1187,7 +1188,8 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 
 	migrate_prep_local();
 
-	while ((ret = compact_finished(zone, cc)) == COMPACT_CONTINUE) {
+	while ((ret = compact_finished(zone, cc, migratetype)) ==
+						COMPACT_CONTINUE) {
 		int err;
 
 		switch (isolate_migratepages(zone, cc)) {
@@ -1242,7 +1244,7 @@ static unsigned long compact_zone_order(struct zone *zone, int order,
 		.nr_freepages = 0,
 		.nr_migratepages = 0,
 		.order = order,
-		.migratetype = gfpflags_to_migratetype(gfp_mask),
+		.gfp_mask = gfp_mask,
 		.zone = zone,
 		.mode = mode,
 	};

mm/internal.h

@@ -142,7 +142,7 @@ struct compact_control {
 	bool finished_update_migrate;
 
 	int order;			/* order a direct compactor needs */
-	int migratetype;		/* MOVABLE, RECLAIMABLE etc */
+	const gfp_t gfp_mask;		/* gfp mask of a direct compactor */
 	struct zone *zone;
 	int contended;			/* Signal need_sched() or lock
 					 * contention detected during