blob: 77118bbf3d8b0096a5d30430652c5decdf73093f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * This file contains NUMA specific variables and functions which can
7 * be split away from DISCONTIGMEM and are used on NUMA machines with
8 * contiguous memory.
9 *
10 * 2002/08/07 Erich Focht <efocht@ess.nec.de>
11 */
12
13#include <linux/config.h>
14#include <linux/cpu.h>
15#include <linux/kernel.h>
16#include <linux/mm.h>
17#include <linux/node.h>
18#include <linux/init.h>
19#include <linux/bootmem.h>
20#include <asm/mmzone.h>
21#include <asm/numa.h>
22
23
24/*
25 * The following structures are usually initialized by ACPI or
26 * similar mechanisms and describe the NUMA characteristics of the machine.
27 */
28int num_node_memblks;
29struct node_memblk_s node_memblk[NR_NODE_MEMBLKS];
30struct node_cpuid_s node_cpuid[NR_CPUS];
31/*
32 * This is a matrix with "distances" between nodes, they should be
33 * proportional to the memory access latency ratios.
34 */
35u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
36
37/* Identify which cnode a physical address resides on */
38int
39paddr_to_nid(unsigned long paddr)
40{
41 int i;
42
43 for (i = 0; i < num_node_memblks; i++)
44 if (paddr >= node_memblk[i].start_paddr &&
45 paddr < node_memblk[i].start_paddr + node_memblk[i].size)
46 break;
47
48 return (i < num_node_memblks) ? node_memblk[i].nid : (num_node_memblks ? -1 : 0);
49}