From mboxrd@z Thu Jan  1 00:00:00 1970
From: lukas@wunner.de (Lukas Wunner)
Date: Mon, 4 Sep 2017 07:46:37 +0200
Subject: [PATCH v3 0/8] PM / ACPI / i2c: Deploy runtime PM centric path
 for system sleep
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Message-ID: <20170904054637.GA23707@wunner.de>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, Sep 04, 2017 at 02:17:21AM +0200, Rafael J. Wysocki wrote:
> OTOH I'm starting to think that direct_complete is only theoretically
> useful and may not be actually set very often in practice, whereas it
> adds significant complexity to the code, so I'm not sure about it any
> more.

That makes me come out of the woodwork as a direct_complete fan:

Runtime resuming a discrete GPU on a modern dual GPU laptop takes about
1.5 sec, runtime resuming Thunderbolt controllers more than 2 sec.
A discrete GPU easily consumes 10W, a Thunderbolt controller 2W.

So not having direct_complete would noticeably delay system suspend and
resume as well as reduce battery life.

Lukas