static void __init setup_memory()

in kernel/setup.c [46:92]

• 28 lines of code
• 4 McCabe index (conditional complexity)

static void __init setup_memory(void)
{
	unsigned long ram_start_pfn;
	unsigned long ram_end_pfn;
	phys_addr_t memory_start, memory_end;

	memory_end = memory_start = 0;

	/* Find main memory where is the kernel, we assume its the only one */
	memory_start = memblock_start_of_DRAM();
	memory_end = memblock_end_of_DRAM();

	if (!memory_end) {
		panic("No memory!");
	}

	ram_start_pfn = PFN_UP(memory_start);
	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());

	/* setup bootmem globals (we use no_bootmem, but mm still depends on this) */
	min_low_pfn = ram_start_pfn;
	max_low_pfn = ram_end_pfn;
	max_pfn = ram_end_pfn;

	/*
	 * initialize the boot-time allocator (with low memory only).
	 *
	 * This makes the memory from the end of the kernel to the end of
	 * RAM usable.
	 */
	memblock_reserve(__pa(_stext), _end - _stext);

#ifdef CONFIG_BLK_DEV_INITRD
	/* Then reserve the initrd, if any */
	if (initrd_start && (initrd_end > initrd_start)) {
		unsigned long aligned_start = ALIGN_DOWN(initrd_start, PAGE_SIZE);
		unsigned long aligned_end = ALIGN(initrd_end, PAGE_SIZE);

		memblock_reserve(__pa(aligned_start), aligned_end - aligned_start);
	}
#endif /* CONFIG_BLK_DEV_INITRD */

	early_init_fdt_reserve_self();
	early_init_fdt_scan_reserved_mem();

	memblock_dump_all();
}