linux-stable-rt/arch/ia64/mm/numa.c

74 lines
2.1 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* This file contains NUMA specific variables and functions which can
* be split away from DISCONTIGMEM and are used on NUMA machines with
* contiguous memory.
*
* 2002/08/07 Erich Focht <efocht@ess.nec.de>
*/
#include <linux/config.h>
#include <linux/cpu.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/node.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <asm/mmzone.h>
#include <asm/numa.h>
/*
* The following structures are usually initialized by ACPI or
* similar mechanisms and describe the NUMA characteristics of the machine.
*/
int num_node_memblks;
struct node_memblk_s node_memblk[NR_NODE_MEMBLKS];
struct node_cpuid_s node_cpuid[NR_CPUS];
/*
* This is a matrix with "distances" between nodes, they should be
* proportional to the memory access latency ratios.
*/
u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
/* Identify which cnode a physical address resides on */
int
paddr_to_nid(unsigned long paddr)
{
int i;
for (i = 0; i < num_node_memblks; i++)
if (paddr >= node_memblk[i].start_paddr &&
paddr < node_memblk[i].start_paddr + node_memblk[i].size)
break;
return (i < num_node_memblks) ? node_memblk[i].nid : (num_node_memblks ? -1 : 0);
}
#if defined(CONFIG_SPARSEMEM) && defined(CONFIG_NUMA)
/*
* Because of holes evaluate on section limits.
* If the section of memory exists, then return the node where the section
* resides. Otherwise return node 0 as the default. This is used by
* SPARSEMEM to allocate the SPARSEMEM sectionmap on the NUMA node where
* the section resides.
*/
int early_pfn_to_nid(unsigned long pfn)
{
int i, section = pfn >> PFN_SECTION_SHIFT, ssec, esec;
for (i = 0; i < num_node_memblks; i++) {
ssec = node_memblk[i].start_paddr >> PA_SECTION_SHIFT;
esec = (node_memblk[i].start_paddr + node_memblk[i].size +
((1L << PA_SECTION_SHIFT) - 1)) >> PA_SECTION_SHIFT;
if (section >= ssec && section < esec)
return node_memblk[i].nid;
}
return 0;
}
#endif