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| author | Siddha, Suresh B <suresh.b.siddha@intel.com> | 2006-06-27 02:54:42 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-27 17:32:45 -0700 |
| commit | 5c45bf279d378d436ce45825c0f136696c7b6109 (patch) | |
| tree | 80e2fcf4866b84fccb787562e1a83b16f4bc8850 /arch/x86_64/kernel/smpboot.c | |
| parent | 369381694ddcf03f1de403501c8b97099b5109ec (diff) | |
| download | linux-5c45bf279d378d436ce45825c0f136696c7b6109.tar.gz | |
[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>
Diffstat (limited to 'arch/x86_64/kernel/smpboot.c')
| -rw-r--r-- | arch/x86_64/kernel/smpboot.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c index 4e9755179ecf5..540c0ccbcccc8 100644 --- a/arch/x86_64/kernel/smpboot.c +++ b/arch/x86_64/kernel/smpboot.c @@ -455,10 +455,12 @@ cpumask_t cpu_coregroup_map(int cpu) struct cpuinfo_x86 *c = cpu_data + cpu; /* * For perf, we return last level cache shared map. - * TBD: when power saving sched policy is added, we will return - * cpu_core_map when power saving policy is enabled + * And for power savings, we return cpu_core_map */ - return c->llc_shared_map; + if (sched_mc_power_savings || sched_smt_power_savings) + return cpu_core_map[cpu]; + else + return c->llc_shared_map; } /* representing cpus for which sibling maps can be computed */ |