sched: Disable SD_PREFER_LOCAL for MC/CPU domains

Yanmin reported that both tbench and hackbench were significantly
hurt by trying to keep tasks local on these domains, esp on small
cache machines.

So disable it in order to promote spreading outside of the cache
domains.

Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1255083400.8802.15.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index 25a9284..d823c24 100644 (file)
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -143,6 +143,7 @@ extern unsigned long node_remap_size[];
                                | 1*SD_BALANCE_FORK                     \
                                | 0*SD_BALANCE_WAKE                     \
                                | 1*SD_WAKE_AFFINE                      \
+                               | 1*SD_PREFER_LOCAL                     \
                                | 0*SD_SHARE_CPUPOWER                   \
                                | 0*SD_POWERSAVINGS_BALANCE             \
                                | 0*SD_SHARE_PKG_RESOURCES              \

diff --git a/include/linux/topology.h b/include/linux/topology.h
index fc0bf3e..57e6357 100644 (file)
--- a/include/linux/topology.h
+++ b/include/linux/topology.h
@@ -129,7 +129,7 @@ int arch_update_cpu_topology(void);
                                | 1*SD_BALANCE_FORK                     \
                                | 0*SD_BALANCE_WAKE                     \
                                | 1*SD_WAKE_AFFINE                      \
-                               | 1*SD_PREFER_LOCAL                     \
+                               | 0*SD_PREFER_LOCAL                     \
                                | 0*SD_SHARE_CPUPOWER                   \
                                | 1*SD_SHARE_PKG_RESOURCES              \
                                | 0*SD_SERIALIZE                        \
@@ -162,7 +162,7 @@ int arch_update_cpu_topology(void);
                                | 1*SD_BALANCE_FORK                     \
                                | 0*SD_BALANCE_WAKE                     \
                                | 1*SD_WAKE_AFFINE                      \
-                               | 1*SD_PREFER_LOCAL                     \
+                               | 0*SD_PREFER_LOCAL                     \
                                | 0*SD_SHARE_CPUPOWER                   \
                                | 0*SD_SHARE_PKG_RESOURCES              \
                                | 0*SD_SERIALIZE                        \