linux-kernel - Re: [PATCH 2/2] PM / Runtime: use deferrable timer for autosuspend

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Message-ID: <20160113190220.GC9821@amd>
Date:	Wed, 13 Jan 2016 20:02:20 +0100
From:	Pavel Machek <pavel@....cz>
To:	Lucas Stach <l.stach@...gutronix.de>
Cc:	"Rafael J . Wysocki" <rjw@...ysocki.net>,
	Thomas Gleixner <tglx@...utronix.de>, linux-pm@...r.kernel.org,
	linux-kernel@...r.kernel.org, patchwork-lst@...gutronix.de
Subject: Re: [PATCH 2/2] PM / Runtime: use deferrable timer for autosuspend

On Tue 2016-01-12 18:17:20, Lucas Stach wrote:
> The timeouts used in PM autosuspend are relatively coarse (the shortest
> I could find in a quick search through the kernel is 50ms). As they are
> already handled relaxed by saving the overhead of always rearming the
> timer by opportunistically suspending a device a bit early, it should
> not matter if the the timeout is missed slightly.
> 
> By using a deferrable timer the CPU will not be woken just to handle
> the autosuspend timeout, but handling will be batched with other
> wakeups in the system.
> 
> Signed-off-by: Lucas Stach <l.stach@...gutronix.de>

Acked-by: Pavel Machek <pavel@....cz>

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