mm: compaction: refactor compact_node()

Refactor compact_node() to handle both proactive and synchronous compact
memory, which cleanups code a bit.

Link: https://lkml.kernel.org/r/20240208013607.1731817-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/compaction.c b/mm/compaction.c
index 0ea5519e28333cfc8cfbc09e747ee96377f49ec5..12709d0bcf402a6349e9005ca0465a784b7ed23a 100644 (file)
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -2796,25 +2796,27 @@ enum compact_result try_to_compact_pages(gfp_t gfp_mask, unsigned int order,
 }
 
 /*
- * Compact all zones within a node till each zone's fragmentation score
- * reaches within proactive compaction thresholds (as determined by the
- * proactiveness tunable).
+ * compact_node() - compact all zones within a node
+ * @pgdat: The node page data
+ * @proactive: Whether the compaction is proactive
  *
- * It is possible that the function returns before reaching score targets
- * due to various back-off conditions, such as, contention on per-node or
- * per-zone locks.
+ * For proactive compaction, compact till each zone's fragmentation score
+ * reaches within proactive compaction thresholds (as determined by the
+ * proactiveness tunable), it is possible that the function returns before
+ * reaching score targets due to various back-off conditions, such as,
+ * contention on per-node or per-zone locks.
  */
-static void proactive_compact_node(pg_data_t *pgdat)
+static void compact_node(pg_data_t *pgdat, bool proactive)
 {
        int zoneid;
        struct zone *zone;
        struct compact_control cc = {
                .order = -1,
-               .mode = MIGRATE_SYNC_LIGHT,
+               .mode = proactive ? MIGRATE_SYNC_LIGHT : MIGRATE_SYNC,
                .ignore_skip_hint = true,
                .whole_zone = true,
                .gfp_mask = GFP_KERNEL,
-               .proactive_compaction = true,
+               .proactive_compaction = proactive,
        };
 
        for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
@@ -2826,41 +2828,16 @@ static void proactive_compact_node(pg_data_t *pgdat)
 
                compact_zone(&cc, NULL);
 
-               count_compact_events(KCOMPACTD_MIGRATE_SCANNED,
-                                    cc.total_migrate_scanned);
-               count_compact_events(KCOMPACTD_FREE_SCANNED,
-                                    cc.total_free_scanned);
-       }
-}
-
-/* Compact all zones within a node */
-static void compact_node(int nid)
-{
-       pg_data_t *pgdat = NODE_DATA(nid);
-       int zoneid;
-       struct zone *zone;
-       struct compact_control cc = {
-               .order = -1,
-               .mode = MIGRATE_SYNC,
-               .ignore_skip_hint = true,
-               .whole_zone = true,
-               .gfp_mask = GFP_KERNEL,
-       };
-
-
-       for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
-
-               zone = &pgdat->node_zones[zoneid];
-               if (!populated_zone(zone))
-                       continue;
-
-               cc.zone = zone;
-
-               compact_zone(&cc, NULL);
+               if (proactive) {
+                       count_compact_events(KCOMPACTD_MIGRATE_SCANNED,
+                                            cc.total_migrate_scanned);
+                       count_compact_events(KCOMPACTD_FREE_SCANNED,
+                                            cc.total_free_scanned);
+               }
        }
 }
 
-/* Compact all nodes in the system */
+/* Compact all zones of all nodes in the system */
 static void compact_nodes(void)
 {
        int nid;
@@ -2869,7 +2846,7 @@ static void compact_nodes(void)
        lru_add_drain_all();
 
        for_each_online_node(nid)
-               compact_node(nid);
+               compact_node(NODE_DATA(nid), false);
 }
 
 static int compaction_proactiveness_sysctl_handler(struct ctl_table *table, int write,
@@ -2931,7 +2908,7 @@ static ssize_t compact_store(struct device *dev,
                /* Flush pending updates to the LRU lists */
                lru_add_drain_all();
 
-               compact_node(nid);
+               compact_node(NODE_DATA(nid), false);
        }
 
        return count;
@@ -3140,7 +3117,7 @@ static int kcompactd(void *p)
                        unsigned int prev_score, score;
 
                        prev_score = fragmentation_score_node(pgdat);
-                       proactive_compact_node(pgdat);
+                       compact_node(pgdat, true);
                        score = fragmentation_score_node(pgdat);
                        /*
                         * Defer proactive compaction if the fragmentation