kernel-aes67/include/linux/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

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5.0 KiB
C

/*
* include/linux/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 _LINUX_TOPOLOGY_H
#define _LINUX_TOPOLOGY_H
#include <linux/cpumask.h>
#include <linux/bitops.h>
#include <linux/mmzone.h>
#include <linux/smp.h>
#include <asm/topology.h>
#ifndef node_has_online_mem
#define node_has_online_mem(nid) (1)
#endif
#ifndef nr_cpus_node
#define nr_cpus_node(node) \
({ \
cpumask_t __tmp__; \
__tmp__ = node_to_cpumask(node); \
cpus_weight(__tmp__); \
})
#endif
#define for_each_node_with_cpus(node) \
for_each_online_node(node) \
if (nr_cpus_node(node))
#ifndef node_distance
/* Conform to ACPI 2.0 SLIT distance definitions */
#define LOCAL_DISTANCE 10
#define REMOTE_DISTANCE 20
#define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
#endif
#ifndef RECLAIM_DISTANCE
/*
* If the distance between nodes in a system is larger than RECLAIM_DISTANCE
* (in whatever arch specific measurement units returned by node_distance())
* then switch on zone reclaim on boot.
*/
#define RECLAIM_DISTANCE 20
#endif
#ifndef PENALTY_FOR_NODE_WITH_CPUS
#define PENALTY_FOR_NODE_WITH_CPUS (1)
#endif
/*
* Below are the 3 major initializers used in building sched_domains:
* SD_SIBLING_INIT, for SMT domains
* SD_CPU_INIT, for SMP domains
* SD_NODE_INIT, for NUMA domains
*
* Any architecture that cares to do any tuning to these values should do so
* by defining their own arch-specific initializer in include/asm/topology.h.
* A definition there will automagically override these default initializers
* and allow arch-specific performance tuning of sched_domains.
*/
#ifdef CONFIG_SCHED_SMT
/* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
* so can't we drop this in favor of CONFIG_SCHED_SMT?
*/
#define ARCH_HAS_SCHED_WAKE_IDLE
/* Common values for SMT siblings */
#ifndef SD_SIBLING_INIT
#define SD_SIBLING_INIT (struct sched_domain) { \
.span = CPU_MASK_NONE, \
.parent = NULL, \
.groups = NULL, \
.min_interval = 1, \
.max_interval = 2, \
.busy_factor = 8, \
.imbalance_pct = 110, \
.cache_nice_tries = 0, \
.per_cpu_gain = 25, \
.busy_idx = 0, \
.idle_idx = 0, \
.newidle_idx = 1, \
.wake_idx = 0, \
.forkexec_idx = 0, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_NEWIDLE \
| SD_BALANCE_EXEC \
| SD_WAKE_AFFINE \
| SD_WAKE_IDLE \
| SD_SHARE_CPUPOWER, \
.last_balance = jiffies, \
.balance_interval = 1, \
.nr_balance_failed = 0, \
}
#endif
#endif /* CONFIG_SCHED_SMT */
/* Common values for CPUs */
#ifndef SD_CPU_INIT
#define SD_CPU_INIT (struct sched_domain) { \
.span = CPU_MASK_NONE, \
.parent = NULL, \
.groups = NULL, \
.min_interval = 1, \
.max_interval = 4, \
.busy_factor = 64, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.per_cpu_gain = 100, \
.busy_idx = 2, \
.idle_idx = 1, \
.newidle_idx = 2, \
.wake_idx = 1, \
.forkexec_idx = 1, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_NEWIDLE \
| SD_BALANCE_EXEC \
| SD_WAKE_AFFINE \
| BALANCE_FOR_POWER, \
.last_balance = jiffies, \
.balance_interval = 1, \
.nr_balance_failed = 0, \
}
#endif
/* sched_domains SD_ALLNODES_INIT for NUMA machines */
#define SD_ALLNODES_INIT (struct sched_domain) { \
.span = CPU_MASK_NONE, \
.parent = NULL, \
.groups = NULL, \
.min_interval = 64, \
.max_interval = 64*num_online_cpus(), \
.busy_factor = 128, \
.imbalance_pct = 133, \
.cache_hot_time = (10*1000000), \
.cache_nice_tries = 1, \
.busy_idx = 3, \
.idle_idx = 3, \
.newidle_idx = 0, /* unused */ \
.wake_idx = 0, /* unused */ \
.forkexec_idx = 0, /* unused */ \
.per_cpu_gain = 100, \
.flags = SD_LOAD_BALANCE, \
.last_balance = jiffies, \
.balance_interval = 64, \
.nr_balance_failed = 0, \
}
#ifdef CONFIG_SCHED_MC
#ifndef SD_MC_INIT
/* for now its same as SD_CPU_INIT.
* TBD: Tune Domain parameters!
*/
#define SD_MC_INIT SD_CPU_INIT
#endif
#endif
#ifdef CONFIG_NUMA
#ifndef SD_NODE_INIT
#error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
#endif
#endif /* CONFIG_NUMA */
#endif /* _LINUX_TOPOLOGY_H */