kernel-ark/include/asm-i386/topology.h
Con Kolivas 69f7c0a1be [PATCH] sched: remove SMT nice
Remove the SMT-nice feature which idles sibling cpus on SMT cpus to
facilitiate nice working properly where cpu power is shared.  The idling of
cpus in the presence of runnable tasks is considered too fragile, easy to
break with outside code, and the complexity of managing this system if an
architecture comes along with many logical cores sharing cpu power will be
unworkable.

Remove the associated per_cpu_gain variable in sched_domains used only by
this code.

Also:

  The reason is that with dynticks enabled, this code breaks without yet
  further tweaks so dynticks brought on the rapid demise of this code.  So
  either we tweak this code or kill it off entirely.  It was Ingo's preference
  to kill it off.  Either way this needs to happen for 2.6.21 since dynticks
  has gone in.

Signed-off-by: Con Kolivas <kernel@kolivas.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05 07:57:51 -08:00

122 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, \
.child = 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, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_EXEC \
| SD_BALANCE_FORK \
| SD_SERIALIZE \
| 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 */