From 5c45bf279d378d436ce45825c0f136696c7b6109 Mon Sep 17 00:00:00 2001 From: "Siddha, Suresh B" Date: Tue, 27 Jun 2006 02:54:42 -0700 Subject: [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 Cc: Ingo Molnar Cc: Nick Piggin Cc: Con Kolivas Cc: "Chen, Kenneth W" Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-x86_64/topology.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/asm-x86_64') diff --git a/include/asm-x86_64/topology.h b/include/asm-x86_64/topology.h index c4e46e7fa7b..6e7a2e976b0 100644 --- a/include/asm-x86_64/topology.h +++ b/include/asm-x86_64/topology.h @@ -59,6 +59,8 @@ extern int __node_distance(int, int); #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]) +#define mc_capable() (boot_cpu_data.x86_max_cores > 1) +#define smt_capable() (smp_num_siblings > 1) #endif #include -- cgit v1.2.3-70-g09d2