From 6956dc568f34107f1d02b24f87efe7250803fc87 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Fri, 20 Jul 2012 14:19:50 +0800 Subject: sched/numa: Add SD_PERFER_SIBLING to CPU domain Commit 8e7fbcbc22c ("sched: Remove stale power aware scheduling remnants and dysfunctional knobs") removed SD_PERFER_SIBLING from the CPU domain. On NUMA machines this causes that load_balance() doesn't perfer LCPU in same physical CPU package. It causes some actual performance regressions on our NUMA machines from Core2 to NHM and SNB. Adding this domain flag again recovers the performance drop. This change doesn't have any bad impact on any of my benchmarks: specjbb, kbuild, fio, hackbench .. etc, on all my machines. Signed-off-by: Alex Shi Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1342765190-21540-1-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar --- include/linux/topology.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/topology.h b/include/linux/topology.h index e91cd43394df..fec12d667211 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -164,6 +164,7 @@ int arch_update_cpu_topology(void); | 0*SD_SHARE_CPUPOWER \ | 0*SD_SHARE_PKG_RESOURCES \ | 0*SD_SERIALIZE \ + | 1*SD_PREFER_SIBLING \ , \ .last_balance = jiffies, \ .balance_interval = 1, \ -- cgit v1.2.2 From a7e4786b937a3ae918a7520cfdba557a80915fa7 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Sat, 21 Jul 2012 00:54:59 +0530 Subject: sched: Fix comment about PREEMPT_ACTIVE bit location PREEMPT_ACTIVE flag is bit 27, not 28. Fix the comment. Signed-off-by: Srivatsa S. Bhat Cc: paulmck@linux.vnet.ibm.com Cc: josh@joshtriplett.org Cc: rostedt@goodmis.org Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20120720192459.6149.14821.stgit@srivatsabhat.in.ibm.com Signed-off-by: Ingo Molnar --- include/linux/hardirq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index bb7f30971858..305f23cd7cff 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -22,7 +22,7 @@ * * - bits 16-25 are the hardirq count (max # of nested hardirqs: 1024) * - bit 26 is the NMI_MASK - * - bit 28 is the PREEMPT_ACTIVE flag + * - bit 27 is the PREEMPT_ACTIVE flag * * PREEMPT_MASK: 0x000000ff * SOFTIRQ_MASK: 0x0000ff00 -- cgit v1.2.2