Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   =?UTF-8?q?Jan=20H=2E=20Sch=C3=B6nherr?= <jschoenh@amazon.de>
To:     Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     =?UTF-8?q?Jan=20H=2E=20Sch=C3=B6nherr?= <jschoenh@amazon.de>,
        linux-kernel@vger.kernel.org
Subject: [RFC 38/60] cosched: Skip updates on non-CPU runqueues in cfs_rq_util_change()
Date:   Fri,  7 Sep 2018 23:40:25 +0200
Message-Id: <20180907214047.26914-39-jschoenh@amazon.de>
In-Reply-To: <20180907214047.26914-1-jschoenh@amazon.de>
References: <20180907214047.26914-1-jschoenh@amazon.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

The function cfs_rq_util_change() notifies frequency governors of
utilization changes, so that they can be scheduler driven. This is
coupled to per CPU runqueue statistics. So, don't do anything
when called for non-CPU runqueues.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
---
 kernel/sched/fair.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a2945355f823..33e3f759eb99 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3015,7 +3015,16 @@ static inline void update_cfs_group(struct sched_entity *se)
 
 static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq, int flags)
 {
-	struct rq *rq = rq_of(cfs_rq);
+	struct rq *rq = hrq_of(cfs_rq);
+
+#ifdef CONFIG_COSCHEDULING
+	/*
+	 * This function is currently only well defined for per-CPU
+	 * runqueues. Don't execute it for anything else.
+	 */
+	if (rq->sdrq_data.level)
+		return;
+#endif
 
 	if (&rq->cfs == cfs_rq || (flags & SCHED_CPUFREQ_MIGRATION)) {
 		/*
-- 
2.9.3.1.gcba166c.dirty