From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 4 Sep 2009 09:32:54 +0000 (+0200)
Subject: sched: Turn on SD_BALANCE_NEWIDLE
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=840a0653100dbde599ae8ddf83fa214dfa5fd1aa;p=deliverable%2Flinux.git

sched: Turn on SD_BALANCE_NEWIDLE

Start the re-tuning of the balancer by turning on newidle.

It improves hackbench performance and parallelism on a 4x4 box.
The "perf stat --repeat 10" measurements give us:

  domain0             domain1
  .......................................
 -SD_BALANCE_NEWIDLE -SD_BALANCE_NEWIDLE:
   2041.273208  task-clock-msecs         #      9.354 CPUs    ( +-   0.363% )

 +SD_BALANCE_NEWIDLE -SD_BALANCE_NEWIDLE:
   2086.326925  task-clock-msecs         #     11.934 CPUs    ( +-   0.301% )

 +SD_BALANCE_NEWIDLE +SD_BALANCE_NEWIDLE:
   2115.289791  task-clock-msecs         #     12.158 CPUs    ( +-   0.263% )

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <new-submission>
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 be29eb81fb06..ef7bc7fc2528 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -142,7 +142,7 @@ extern unsigned long node_remap_size[];
 	.forkexec_idx		= SD_FORKEXEC_IDX,			\
 									\
 	.flags			= 1*SD_LOAD_BALANCE			\
-				| 0*SD_BALANCE_NEWIDLE			\
+				| 1*SD_BALANCE_NEWIDLE			\
 				| 1*SD_BALANCE_EXEC			\
 				| 1*SD_BALANCE_FORK			\
 				| 0*SD_WAKE_IDLE			\
diff --git a/include/linux/topology.h b/include/linux/topology.h
index fe2c0329f82f..66774fddec9b 100644
--- a/include/linux/topology.h
+++ b/include/linux/topology.h
@@ -126,7 +126,7 @@ int arch_update_cpu_topology(void);
 	.forkexec_idx		= 1,					\
 									\
 	.flags			= 1*SD_LOAD_BALANCE			\
-				| 0*SD_BALANCE_NEWIDLE			\
+				| 1*SD_BALANCE_NEWIDLE			\
 				| 1*SD_BALANCE_EXEC			\
 				| 1*SD_BALANCE_FORK			\
 				| 0*SD_WAKE_IDLE			\
@@ -160,7 +160,7 @@ int arch_update_cpu_topology(void);
 	.forkexec_idx		= 1,					\
 									\
 	.flags			= 1*SD_LOAD_BALANCE			\
-				| 0*SD_BALANCE_NEWIDLE			\
+				| 1*SD_BALANCE_NEWIDLE			\
 				| 1*SD_BALANCE_EXEC			\
 				| 1*SD_BALANCE_FORK			\
 				| 0*SD_WAKE_IDLE			\