mm/ARM64: prepare for removing num_physpages and simplify mem_init()

Prepare for removing num_physpages and simplify mem_init().
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm64/mm/init.c

@@ -272,59 +272,17 @@ static void __init free_unused_memmap(void)
  */
 void __init mem_init(void)
 {
-	unsigned long reserved_pages, free_pages;
-	struct memblock_region *reg;
-
 	arm64_swiotlb_init();
 
 	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 
 #ifndef CONFIG_SPARSEMEM_VMEMMAP
-	/* this will put all unused low memory onto the freelists */
 	free_unused_memmap();
 #endif
-
+	/* this will put all unused low memory onto the freelists */
 	free_all_bootmem();
 
-	reserved_pages = free_pages = 0;
-
-	for_each_memblock(memory, reg) {
-		unsigned int pfn1, pfn2;
-		struct page *page, *end;
-
-		pfn1 = __phys_to_pfn(reg->base);
-		pfn2 = pfn1 + __phys_to_pfn(reg->size);
-
-		page = pfn_to_page(pfn1);
-		end  = pfn_to_page(pfn2 - 1) + 1;
-
-		do {
-			if (PageReserved(page))
-				reserved_pages++;
-			else if (!page_count(page))
-				free_pages++;
-			page++;
-		} while (page < end);
-	}
-
-	/*
-	 * Since our memory may not be contiguous, calculate the real number
-	 * of pages we have in this system.
-	 */
-	pr_info("Memory:");
-	num_physpages = 0;
-	for_each_memblock(memory, reg) {
-		unsigned long pages = memblock_region_memory_end_pfn(reg) -
-			memblock_region_memory_base_pfn(reg);
-		num_physpages += pages;
-		printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
-	}
-	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
-
-	pr_notice("Memory: %luk/%luk available, %luk reserved\n",
-		  nr_free_pages() << (PAGE_SHIFT-10),
-		  free_pages << (PAGE_SHIFT-10),
-		  reserved_pages << (PAGE_SHIFT-10));
+	mem_init_print_info();
 
 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 #define MLM(b, t) b, t, ((t) - (b)) >> 20
@@ -366,7 +324,7 @@ void __init mem_init(void)
 	BUILD_BUG_ON(TASK_SIZE_64			> MODULES_VADDR);
 	BUG_ON(TASK_SIZE_64				> MODULES_VADDR);
 
-	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
+	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 		extern int sysctl_overcommit_memory;
 		/*
 		 * On a machine this small we won't get anywhere without