+ mm-compaction-refactor-compact_node.patch added to mm-unstable branch

+ mm-compaction-refactor-compact_node.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: compaction: refactor compact_node()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-compaction-refactor-compact_node.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-compaction-refactor-compact_node.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Kefeng Wang <wangkefeng.wang@huawei.com>
Subject: mm: compaction: refactor compact_node()
Date: Thu, 8 Feb 2024 09:36:07 +0800

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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/compaction.c |   65 ++++++++++++++--------------------------------
 1 file changed, 21 insertions(+), 44 deletions(-)

--- a/mm/compaction.c~mm-compaction-refactor-compact_node
+++ a/mm/compaction.c
@@ -2885,25 +2885,27 @@ enum compact_result try_to_compact_pages
 }
 
 /*
- * 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++) {
@@ -2915,41 +2917,16 @@ static void proactive_compact_node(pg_da
 
 		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;
@@ -2958,7 +2935,7 @@ 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,
@@ -3020,7 +2997,7 @@ static ssize_t compact_store(struct devi
 		/* Flush pending updates to the LRU lists */
 		lru_add_drain_all();
 
-		compact_node(nid);
+		compact_node(NODE_DATA(nid), false);
 	}
 
 	return count;
@@ -3229,7 +3206,7 @@ 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
_

Patches currently in -mm which might be from wangkefeng.wang@huawei.com are

mm-memory-use-nth_page-in-clear-copy_subpage.patch
s390-use-pfn_swap_entry_folio-in-ptep_zap_swap_entry.patch
mm-use-pfn_swap_entry_folio-in-__split_huge_pmd_locked.patch
mm-use-pfn_swap_entry_to_folio-in-zap_huge_pmd.patch
mm-use-pfn_swap_entry_folio-in-copy_nonpresent_pte.patch
mm-convert-to-should_zap_page-to-should_zap_folio.patch
mm-convert-to-should_zap_page-to-should_zap_folio-fix.patch
mm-convert-mm_counter-to-take-a-folio.patch
mm-convert-mm_counter_file-to-take-a-folio.patch
mm-memory-move-mem_cgroup_charge-into-alloc_anon_folio.patch
mm-compaction-refactor-compact_node.patch