mm: simplify parameter of setup_usemap()

Parameter 'zone' has got needed information, let's remove other
unnecessary parameters.

Link: https://lkml.kernel.org/r/20210122135956.5946-5-bhe@redhat.comSigned-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -6765,25 +6765,22 @@ static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned l
 	return usemapsize / 8;
 }
 
-static void __ref setup_usemap(struct pglist_data *pgdat,
-				struct zone *zone,
-				unsigned long zone_start_pfn,
-				unsigned long zonesize)
+static void __ref setup_usemap(struct zone *zone)
 {
-	unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize);
+	unsigned long usemapsize = usemap_size(zone->zone_start_pfn,
+					       zone->spanned_pages);
 	zone->pageblock_flags = NULL;
 	if (usemapsize) {
 		zone->pageblock_flags =
 			memblock_alloc_node(usemapsize, SMP_CACHE_BYTES,
-					    pgdat->node_id);
+					    zone_to_nid(zone));
 		if (!zone->pageblock_flags)
 			panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n",
-			      usemapsize, zone->name, pgdat->node_id);
+			      usemapsize, zone->name, zone_to_nid(zone));
 	}
 }
 #else
-static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone,
-				unsigned long zone_start_pfn, unsigned long zonesize) {}
+static inline void setup_usemap(struct zone *zone) {}
 #endif /* CONFIG_SPARSEMEM */
 
 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
@@ -6978,7 +6975,7 @@ static void __init free_area_init_core(struct pglist_data *pgdat)
 			continue;
 
 		set_pageblock_order();
-		setup_usemap(pgdat, zone, zone_start_pfn, size);
+		setup_usemap(zone);
 		init_currently_empty_zone(zone, zone_start_pfn, size);
 		memmap_init_zone(zone);
 	}