mm: pass migratetype into memmap_init_zone() and move_pfn_range_to_zone()

On the memory onlining path, we want to start with MIGRATE_ISOLATE, to
un-isolate the pages after memory onlining is complete.  Let's allow
passing in the migratetype.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Charan Teja Reddy <charante@codeaurora.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Link: https://lkml.kernel.org/r/20200819175957.28465-10-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 22 insertions, 13 deletions

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 113edf95b908..bb30e99b7383 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -701,9 +701,14 @@ static void __meminit resize_pgdat_range(struct pglist_data *pgdat, unsigned lon
  * Associate the pfn range with the given zone, initializing the memmaps
  * and resizing the pgdat/zone data to span the added pages. After this
  * call, all affected pages are PG_reserved.
+ *
+ * All aligned pageblocks are initialized to the specified migratetype
+ * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related
+ * zone stats (e.g., nr_isolate_pageblock) are touched.
  */
 void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
-		unsigned long nr_pages, struct vmem_altmap *altmap)
+				  unsigned long nr_pages,
+				  struct vmem_altmap *altmap, int migratetype)
 {
 	struct pglist_data *pgdat = zone->zone_pgdat;
 	int nid = pgdat->node_id;
@@ -728,7 +733,7 @@ void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 	 * are reserved so nobody should be touching them so we should be safe
 	 */
 	memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn,
-			 MEMINIT_HOTPLUG, altmap);
+			 MEMINIT_HOTPLUG, altmap, migratetype);
 
 	set_zone_contiguous(zone);
 }
@@ -808,7 +813,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
 
 	/* associate pfn range with the zone */
 	zone = zone_for_pfn_range(online_type, nid, pfn, nr_pages);
-	move_pfn_range_to_zone(zone, pfn, nr_pages, NULL);
+	move_pfn_range_to_zone(zone, pfn, nr_pages, NULL, MIGRATE_MOVABLE);
 
 	arg.start_pfn = pfn;
 	arg.nr_pages = nr_pages;
diff --git a/mm/memremap.c b/mm/memremap.c
index 198083453182..73a206d0f645 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -266,7 +266,8 @@ static int pagemap_range(struct dev_pagemap *pgmap, struct mhp_params *params,
 
 		zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE];
 		move_pfn_range_to_zone(zone, PHYS_PFN(range->start),
-				PHYS_PFN(range_len(range)), params->altmap);
+				PHYS_PFN(range_len(range)), params->altmap,
+				MIGRATE_MOVABLE);
 	}
 
 	mem_hotplug_done();
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7a99ed299443..f7f292f1d108 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5990,10 +5990,15 @@ overlap_memmap_init(unsigned long zone, unsigned long *pfn)
  * Initially all pages are reserved - free ones are freed
  * up by memblock_free_all() once the early boot process is
  * done. Non-atomic initialization, single-pass.
+ *
+ * All aligned pageblocks are initialized to the specified migratetype
+ * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related
+ * zone stats (e.g., nr_isolate_pageblock) are touched.
  */
 void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
-		unsigned long start_pfn, enum meminit_context context,
-		struct vmem_altmap *altmap)
+		unsigned long start_pfn,
+		enum meminit_context context,
+		struct vmem_altmap *altmap, int migratetype)
 {
 	unsigned long pfn, end_pfn = start_pfn + size;
 	struct page *page;
@@ -6037,14 +6042,12 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 			__SetPageReserved(page);
 
 		/*
-		 * Mark the block movable so that blocks are reserved for
-		 * movable at startup. This will force kernel allocations
-		 * to reserve their blocks rather than leaking throughout
-		 * the address space during boot when many long-lived
-		 * kernel allocations are made.
+		 * Usually, we want to mark the pageblock MIGRATE_MOVABLE,
+		 * such that unmovable allocations won't be scattered all
+		 * over the place during system boot.
 		 */
 		if (IS_ALIGNED(pfn, pageblock_nr_pages)) {
-			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
+			set_pageblock_migratetype(page, migratetype);
 			cond_resched();
 		}
 		pfn++;
@@ -6144,7 +6147,7 @@ void __meminit __weak memmap_init(unsigned long size, int nid,
 		if (end_pfn > start_pfn) {
 			size = end_pfn - start_pfn;
 			memmap_init_zone(size, nid, zone, start_pfn,
-					 MEMINIT_EARLY, NULL);
+					 MEMINIT_EARLY, NULL, MIGRATE_MOVABLE);
 		}
 	}
 }