linux/arch/ia64/kernel/numa.c
KAMEZAWA Hiroyuki 3212fe1594 [PATCH] cpu to node relationship fixup: map cpu to node
Assume that a cpu is *physically* offlined at boot time...

Because smpboot.c::smp_boot_cpu_map() canoot find cpu's sapicid,
numa.c::build_cpu_to_node_map() cannot build cpu<->node map for
offlined cpu.

For such cpus, cpu_to_node map should be fixed at cpu-hot-add.
This mapping should be done before cpu onlining.

This patch also handles cpu hotremove case.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-25 17:38:36 -07:00

85 lines
2.4 KiB
C

/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* ia64 kernel NUMA specific stuff
*
* Copyright (C) 2002 Erich Focht <efocht@ess.nec.de>
* Copyright (C) 2004 Silicon Graphics, Inc.
* Jesse Barnes <jbarnes@sgi.com>
*/
#include <linux/topology.h>
#include <linux/module.h>
#include <asm/processor.h>
#include <asm/smp.h>
u16 cpu_to_node_map[NR_CPUS] __cacheline_aligned;
EXPORT_SYMBOL(cpu_to_node_map);
cpumask_t node_to_cpu_mask[MAX_NUMNODES] __cacheline_aligned;
void __cpuinit map_cpu_to_node(int cpu, int nid)
{
int oldnid;
if (nid < 0) { /* just initialize by zero */
cpu_to_node_map[cpu] = 0;
return;
}
/* sanity check first */
oldnid = cpu_to_node_map[cpu];
if (cpu_isset(cpu, node_to_cpu_mask[oldnid])) {
return; /* nothing to do */
}
/* we don't have cpu-driven node hot add yet...
In usual case, node is created from SRAT at boot time. */
if (!node_online(nid))
nid = first_online_node;
cpu_to_node_map[cpu] = nid;
cpu_set(cpu, node_to_cpu_mask[nid]);
return;
}
void __cpuinit unmap_cpu_from_node(int cpu, int nid)
{
WARN_ON(!cpu_isset(cpu, node_to_cpu_mask[nid]));
WARN_ON(cpu_to_node_map[cpu] != nid);
cpu_to_node_map[cpu] = 0;
cpu_clear(cpu, node_to_cpu_mask[nid]);
}
/**
* build_cpu_to_node_map - setup cpu to node and node to cpumask arrays
*
* Build cpu to node mapping and initialize the per node cpu masks using
* info from the node_cpuid array handed to us by ACPI.
*/
void __init build_cpu_to_node_map(void)
{
int cpu, i, node;
for(node=0; node < MAX_NUMNODES; node++)
cpus_clear(node_to_cpu_mask[node]);
for(cpu = 0; cpu < NR_CPUS; ++cpu) {
node = -1;
for (i = 0; i < NR_CPUS; ++i)
if (cpu_physical_id(cpu) == node_cpuid[i].phys_id) {
node = node_cpuid[i].nid;
break;
}
map_cpu_to_node(cpu, node);
}
}