mm: compaction: remove unnecessary is_via_compact_memory() checks

Remove from all paths not reachable via /proc/sys/vm/compact_memory.

Link: https://lkml.kernel.org/r/20230519123959.77335-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/compaction.c

@@ -2280,9 +2280,6 @@ bool compaction_zonelist_suitable(struct alloc_context *ac, int order,
 		unsigned long available;
 		unsigned long watermark;
 
-		if (is_via_compact_memory(order))
-			return true;
-
 		/* Allocation can already succeed, nothing to do */
 		watermark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK);
 		if (zone_watermark_ok(zone, order, watermark,
@@ -2848,9 +2845,6 @@ static bool kcompactd_node_suitable(pg_data_t *pgdat)
 		if (!populated_zone(zone))
 			continue;
 
-		if (is_via_compact_memory(pgdat->kcompactd_max_order))
-			return true;
-
 		/* Allocation can already succeed, check other zones */
 		if (zone_watermark_ok(zone, pgdat->kcompactd_max_order,
 				      min_wmark_pages(zone),
@@ -2895,9 +2889,6 @@ static void kcompactd_do_work(pg_data_t *pgdat)
 		if (compaction_deferred(zone, cc.order))
 			continue;
 
-		if (is_via_compact_memory(cc.order))
-			goto compact;
-
 		/* Allocation can already succeed, nothing to do */
 		if (zone_watermark_ok(zone, cc.order,
 				      min_wmark_pages(zone), zoneid, 0))
@@ -2906,7 +2897,7 @@ static void kcompactd_do_work(pg_data_t *pgdat)
 		if (compaction_suitable(zone, cc.order,
 					zoneid) != COMPACT_CONTINUE)
 			continue;
-compact:
+
 		if (kthread_should_stop())
 			return;
 

mm/vmscan.c

@@ -6399,9 +6399,6 @@ static inline bool should_continue_reclaim(struct pglist_data *pgdat,
 		if (!managed_zone(zone))
 			continue;
 
-		if (sc->order == -1) /* is_via_compact_memory() */
-			return false;
-
 		/* Allocation can already succeed, nothing to do */
 		if (zone_watermark_ok(zone, sc->order, min_wmark_pages(zone),
 				      sc->reclaim_idx, 0))
@@ -6598,9 +6595,6 @@ static inline bool compaction_ready(struct zone *zone, struct scan_control *sc)
 {
 	unsigned long watermark;
 
-	if (sc->order == -1) /* is_via_compact_memory() */
-		goto suitable;
-
 	/* Allocation can already succeed, nothing to do */
 	if (zone_watermark_ok(zone, sc->order, min_wmark_pages(zone),
 			      sc->reclaim_idx, 0))
@@ -6610,7 +6604,7 @@ static inline bool compaction_ready(struct zone *zone, struct scan_control *sc)
 	if (compaction_suitable(zone, sc->order,
 				sc->reclaim_idx) == COMPACT_SKIPPED)
 		return false;
-suitable:
+
 	/*
 	 * Compaction is already possible, but it takes time to run and there
 	 * are potentially other callers using the pages just freed. So proceed