linux/include/asm-i386/topology.h
Zhang, Yanmin 69dcc99199 [PATCH] Export cpu topology in sysfs
The patch implements cpu topology exportation by sysfs.

Items (attributes) are similar to /proc/cpuinfo.

1) /sys/devices/system/cpu/cpuX/topology/physical_package_id:
	represent the physical package id of  cpu X;
2) /sys/devices/system/cpu/cpuX/topology/core_id:
	represent the cpu core id to cpu X;
3) /sys/devices/system/cpu/cpuX/topology/thread_siblings:
	represent the thread siblings to cpu X in the same core;
4) /sys/devices/system/cpu/cpuX/topology/core_siblings:
	represent the thread siblings to cpu X in the same physical package;

To implement it in an architecture-neutral way, a new source file,
driver/base/topology.c, is to export the 5 attributes.

If one architecture wants to support this feature, it just needs to
implement 4 defines, typically in file include/asm-XXX/topology.h.
The 4 defines are:
#define topology_physical_package_id(cpu)
#define topology_core_id(cpu)
#define topology_thread_siblings(cpu)
#define topology_core_siblings(cpu)

The type of **_id is int.
The type of siblings is cpumask_t.

To be consistent on all architectures, the 4 attributes should have
deafult values if their values are unavailable. Below is the rule.

1) physical_package_id: If cpu has no physical package id, -1 is the
default value.

2) core_id: If cpu doesn't support multi-core, its core id is 0.

3) thread_siblings: Just include itself, if the cpu doesn't support
HT/multi-thread.

4) core_siblings: Just include itself, if the cpu doesn't support
multi-core and HT/Multi-thread.

So be careful when declaring the 4 defines in include/asm-XXX/topology.h.

If an attribute isn't defined on an architecture, it won't be exported.

Thank Nathan, Greg, Andi, Paul and Venki.

The patch provides defines for i386/x86_64/ia64.

Signed-off-by: Zhang, Yanmin <yanmin.zhang@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:09 -08:00

116 lines
3.2 KiB
C

/*
* linux/include/asm-i386/topology.h
*
* Written by: Matthew Dobson, IBM Corporation
*
* Copyright (C) 2002, IBM Corp.
*
* All rights reserved.
*
* 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, GOOD TITLE or
* NON INFRINGEMENT. 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <colpatch@us.ibm.com>
*/
#ifndef _ASM_I386_TOPOLOGY_H
#define _ASM_I386_TOPOLOGY_H
#ifdef CONFIG_SMP
#define topology_physical_package_id(cpu) \
(phys_proc_id[cpu] == BAD_APICID ? -1 : phys_proc_id[cpu])
#define topology_core_id(cpu) \
(cpu_core_id[cpu] == BAD_APICID ? 0 : cpu_core_id[cpu])
#define topology_core_siblings(cpu) (cpu_core_map[cpu])
#define topology_thread_siblings(cpu) (cpu_sibling_map[cpu])
#endif
#ifdef CONFIG_NUMA
#include <asm/mpspec.h>
#include <linux/cpumask.h>
/* Mappings between logical cpu number and node number */
extern cpumask_t node_2_cpu_mask[];
extern int cpu_2_node[];
/* Returns the number of the node containing CPU 'cpu' */
static inline int cpu_to_node(int cpu)
{
return cpu_2_node[cpu];
}
/* Returns the number of the node containing Node 'node'. This architecture is flat,
so it is a pretty simple function! */
#define parent_node(node) (node)
/* Returns a bitmask of CPUs on Node 'node'. */
static inline cpumask_t node_to_cpumask(int node)
{
return node_2_cpu_mask[node];
}
/* Returns the number of the first CPU on Node 'node'. */
static inline int node_to_first_cpu(int node)
{
cpumask_t mask = node_to_cpumask(node);
return first_cpu(mask);
}
#define pcibus_to_node(bus) ((long) (bus)->sysdata)
#define pcibus_to_cpumask(bus) node_to_cpumask(pcibus_to_node(bus))
/* sched_domains SD_NODE_INIT for NUMAQ machines */
#define SD_NODE_INIT (struct sched_domain) { \
.span = CPU_MASK_NONE, \
.parent = NULL, \
.groups = NULL, \
.min_interval = 8, \
.max_interval = 32, \
.busy_factor = 32, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.busy_idx = 3, \
.idle_idx = 1, \
.newidle_idx = 2, \
.wake_idx = 1, \
.per_cpu_gain = 100, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_EXEC \
| SD_BALANCE_FORK \
| SD_WAKE_BALANCE, \
.last_balance = jiffies, \
.balance_interval = 1, \
.nr_balance_failed = 0, \
}
extern unsigned long node_start_pfn[];
extern unsigned long node_end_pfn[];
extern unsigned long node_remap_size[];
#define node_has_online_mem(nid) (node_start_pfn[nid] != node_end_pfn[nid])
#else /* !CONFIG_NUMA */
/*
* Other i386 platforms should define their own version of the
* above macros here.
*/
#include <asm-generic/topology.h>
#endif /* CONFIG_NUMA */
#endif /* _ASM_I386_TOPOLOGY_H */