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 25a92842dd994f688239186211b0d76b8d5772cb..d823c245f63bf0fc26bd2ac9425b913903f928bb 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 fc0bf3edeb6705814af2b1ba8428fc0a39e78e0b..57e63579bfdd7f193511675fc9ed26141b586638 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                        \