linux/include/asm-i386/topology.h
Siddha, Suresh B 5c45bf279d [PATCH] sched: mc/smt power savings sched policy
sysfs entries 'sched_mc_power_savings' and 'sched_smt_power_savings' in
/sys/devices/system/cpu/ control the MC/SMT power savings policy for the
scheduler.

Based on the values (1-enable, 0-disable) for these controls, sched groups
cpu power will be determined for different domains.  When power savings
policy is enabled and under light load conditions, scheduler will minimize
the physical packages/cpu cores carrying the load and thus conserving
power(with a perf impact based on the workload characteristics...  see OLS
2005 CMP kernel scheduler paper for more details..)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Con Kolivas <kernel@kolivas.org>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:45 -07:00

121 lines
3.3 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_X86_HT
#define topology_physical_package_id(cpu) (cpu_data[cpu].phys_proc_id)
#define topology_core_id(cpu) (cpu_data[cpu].cpu_core_id)
#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 */
extern cpumask_t cpu_coregroup_map(int cpu);
#ifdef CONFIG_SMP
#define mc_capable() (boot_cpu_data.x86_max_cores > 1)
#define smt_capable() (smp_num_siblings > 1)
#endif
#endif /* _ASM_I386_TOPOLOGY_H */