remarkable-linux/include/asm-powerpc/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

117 lines
2.3 KiB
C

#ifndef _ASM_POWERPC_TOPOLOGY_H
#define _ASM_POWERPC_TOPOLOGY_H
#ifdef __KERNEL__
struct sys_device;
struct device_node;
#ifdef CONFIG_NUMA
#include <asm/mmzone.h>
static inline int cpu_to_node(int cpu)
{
return numa_cpu_lookup_table[cpu];
}
#define parent_node(node) (node)
static inline cpumask_t node_to_cpumask(int node)
{
return numa_cpumask_lookup_table[node];
}
static inline int node_to_first_cpu(int node)
{
cpumask_t tmp;
tmp = node_to_cpumask(node);
return first_cpu(tmp);
}
int of_node_to_nid(struct device_node *device);
struct pci_bus;
#ifdef CONFIG_PCI
extern int pcibus_to_node(struct pci_bus *bus);
#else
static inline int pcibus_to_node(struct pci_bus *bus)
{
return -1;
}
#endif
#define pcibus_to_cpumask(bus) (pcibus_to_node(bus) == -1 ? \
CPU_MASK_ALL : \
node_to_cpumask(pcibus_to_node(bus)) \
)
/* sched_domains SD_NODE_INIT for PPC64 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_NEWIDLE \
| SD_WAKE_IDLE \
| SD_SERIALIZE \
| SD_WAKE_BALANCE, \
.last_balance = jiffies, \
.balance_interval = 1, \
.nr_balance_failed = 0, \
}
extern void __init dump_numa_cpu_topology(void);
extern int sysfs_add_device_to_node(struct sys_device *dev, int nid);
extern void sysfs_remove_device_from_node(struct sys_device *dev, int nid);
#else
static inline int of_node_to_nid(struct device_node *device)
{
return 0;
}
static inline void dump_numa_cpu_topology(void) {}
static inline int sysfs_add_device_to_node(struct sys_device *dev, int nid)
{
return 0;
}
static inline void sysfs_remove_device_from_node(struct sys_device *dev,
int nid)
{
}
#include <asm-generic/topology.h>
#endif /* CONFIG_NUMA */
#ifdef CONFIG_SMP
#include <asm/cputable.h>
#define smt_capable() (cpu_has_feature(CPU_FTR_SMT))
#ifdef CONFIG_PPC64
#include <asm/smp.h>
#define topology_thread_siblings(cpu) (cpu_sibling_map[cpu])
#endif
#endif
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_TOPOLOGY_H */