mm: use pgdat_end_pfn() to simplify the code in others

Use "pgdat_end_pfn()" instead of "pgdat->node_start_pfn +
pgdat->node_spanned_pages".  Simplify the code, no functional change.
Signed-off-by: NXishi Qiu <qiuxishi@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/proc/kcore.c

@@ -255,8 +255,7 @@ static int kcore_update_ram(void)
 	end_pfn = 0;
 	for_each_node_state(nid, N_MEMORY) {
 		unsigned long node_end;
-		node_end  = NODE_DATA(nid)->node_start_pfn +
-			NODE_DATA(nid)->node_spanned_pages;
+		node_end = node_end_pfn(nid);
 		if (end_pfn < node_end)
 			end_pfn = node_end;
 	}

mm/bootmem.c

@@ -784,7 +784,7 @@ void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
 		return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 
 	/* update goal according ...MAX_DMA32_PFN */
-	end_pfn = pgdat->node_start_pfn + pgdat->node_spanned_pages;
+	end_pfn = pgdat_end_pfn(pgdat);
 
 	if (end_pfn > MAX_DMA32_PFN + (128 >> (20 - PAGE_SHIFT)) &&
 	    (goal >> PAGE_SHIFT) < MAX_DMA32_PFN) {

mm/memory_hotplug.c

@@ -365,8 +365,7 @@ static int __meminit move_pfn_range_right(struct zone *z1, struct zone *z2,
 static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
 			    unsigned long end_pfn)
 {
-	unsigned long old_pgdat_end_pfn =
-		pgdat->node_start_pfn + pgdat->node_spanned_pages;
+	unsigned long old_pgdat_end_pfn = pgdat_end_pfn(pgdat);
 
 	if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
 		pgdat->node_start_pfn = start_pfn;
@@ -579,9 +578,9 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
 static void shrink_pgdat_span(struct pglist_data *pgdat,
 			      unsigned long start_pfn, unsigned long end_pfn)
 {
-	unsigned long pgdat_start_pfn =  pgdat->node_start_pfn;
-	unsigned long pgdat_end_pfn =
-		pgdat->node_start_pfn + pgdat->node_spanned_pages;
+	unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
+	unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */
+	unsigned long pgdat_end_pfn = p;
 	unsigned long pfn;
 	struct mem_section *ms;
 	int nid = pgdat->node_id;