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From: Joel Fernandes <joelaf@google.com>
To: linux-kernel@vger.kernel.org
Cc: Joel Fernandes <joelaf@google.com>, Ingo Molnar <mingo@redhat.com>,
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Subject: [PATCH RFC 5/5] sched/fair: remove impossible condition from find_idlest_group_cpu
Date: Sat, 28 Oct 2017 02:59:41 -0700
Message-Id: <20171028095941.4773-6-joelaf@google.com>
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find_idlest_group_cpu goes through CPUs of a group previous selected by
find_idlest_group. find_idlest_group returns NULL if the local group is the
selected one and doesn't execute find_idlest_group_cpu if the group to which
'cpu' belongs to is chosen. So we're always guaranteed to call
find_idlest_group_cpu with a group to which cpu is non-local. This makes one of
the conditions in find_idlest_group_cpu an impossible one, which we can get rid
off.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brendan Jackman <brendan.jackman@arm.com>
Cc: Dietmar <dietmar.eggemann@arm.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 5c49fdb4c508..740602ce799f 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5922,7 +5922,7 @@ find_idlest_group_cpu(struct sched_group *group, struct task_struct *p, int this
 			}
 		} else if (shallowest_idle_cpu == -1) {
 			load = weighted_cpuload(cpu_rq(i));
-			if (load < min_load || (load == min_load && i == this_cpu)) {
+			if (load < min_load) {
 				min_load = load;
 				least_loaded_cpu = i;
 			}
-- 
2.15.0.rc2.357.g7e34df9404-goog