From 1466643489241e2c9480c181129a7d83e96fa137 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Wed, 26 Apr 2017 17:36:41 +0200
Subject: [PATCH] sched/topology: Remove FORCE_SD_OVERLAP

References: bnc#978907 Scheduler performance -- topology
Patch-mainline: v4.13-rc1
Git-commit: af85596c74de2fd9abb87501ae280038ac28a3f4

Its an obsolete debug mechanism and future code wants to rely on
properties this undermines.

Namely, it would be good to assume that SD_OVERLAP domains have
children, but if we build the entire hierarchy with SD_OVERLAP this is
obviously false.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 kernel/sched/features.h | 1 -
 kernel/sched/topology.c | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index ce7b4b6ac733..d3fb15555291 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -77,7 +77,6 @@ SCHED_FEAT(WARN_DOUBLE_CLOCK, false)
 SCHED_FEAT(RT_PUSH_IPI, true)
 #endif
 
-SCHED_FEAT(FORCE_SD_OVERLAP, false)
 SCHED_FEAT(RT_RUNTIME_SHARE, true)
 SCHED_FEAT(LB_MIN, false)
 SCHED_FEAT(ATTACH_AGE_LOAD, true)
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 20ca78d2514c..09563c1d1d5b 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1455,7 +1455,7 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att
 			sd = build_sched_domain(tl, cpu_map, attr, sd, i);
 			if (tl == sched_domain_topology)
 				*per_cpu_ptr(d.sd, i) = sd;
-			if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP))
+			if (tl->flags & SDTL_OVERLAP)
 				sd->flags |= SD_OVERLAP;
 			if (cpumask_equal(cpu_map, sched_domain_span(sd)))
 				break;