[PATCH v5 1/5] mm: move mirrored memory overlap checking to the outer loop

[Yuan Liu]

Move the overlap memmap initialization check from memmap_init_range()
to memmap_init(), and replace the per-PFN check with a memblock-based
check.

Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx>
Reviewed-by: Jason Zeng <jason.zeng@xxxxxxxxx>
Signed-off-by: Yuan Liu <yuan1.liu@xxxxxxxxx>
---
 mm/mm_init.c | 29 +++++------------------------
 1 file changed, 5 insertions(+), 24 deletions(-)

diff --git a/mm/mm_init.c b/mm/mm_init.c
index f9f8e1af921c..24e103a402b0 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -783,28 +783,6 @@ void __meminit init_deferred_page(unsigned long pfn, int nid)
 	__init_deferred_page(pfn, nid);
 }
 
-/* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */
-static bool __meminit
-overlap_memmap_init(unsigned long zone, unsigned long *pfn)
-{
-	static struct memblock_region *r __meminitdata;
-
-	if (mirrored_kernelcore && zone == ZONE_MOVABLE) {
-		if (!r || *pfn >= memblock_region_memory_end_pfn(r)) {
-			for_each_mem_region(r) {
-				if (*pfn < memblock_region_memory_end_pfn(r))
-					break;
-			}
-		}
-		if (*pfn >= memblock_region_memory_base_pfn(r) &&
-		    memblock_is_mirror(r)) {
-			*pfn = memblock_region_memory_end_pfn(r);
-			return true;
-		}
-	}
-	return false;
-}
-
 /*
  * Only struct pages that correspond to ranges defined by memblock.memory
  * are zeroed and initialized by going through __init_single_page() during
@@ -891,8 +869,6 @@ void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone
 		 * function.  They do not exist on hotplugged memory.
 		 */
 		if (context == MEMINIT_EARLY) {
-			if (overlap_memmap_init(zone, &pfn))
-				continue;
 			if (defer_init(nid, pfn, zone_end_pfn)) {
 				deferred_struct_pages = true;
 				break;
@@ -956,6 +932,7 @@ static void __init memmap_init(void)
 	int i, j, zone_id = 0, nid;
 
 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
+		struct memblock_region *r = &memblock.memory.regions[i];
 		struct pglist_data *node = NODE_DATA(nid);
 
 		for (j = 0; j < MAX_NR_ZONES; j++) {
@@ -964,6 +941,10 @@ static void __init memmap_init(void)
 			if (!populated_zone(zone))
 				continue;
 
+			if (mirrored_kernelcore && j == ZONE_MOVABLE &&
+			    memblock_is_mirror(r))
+				continue;
+
 			memmap_init_zone_range(zone, start_pfn, end_pfn,
 					       &hole_pfn);
 			zone_id = j;
-- 
2.47.3