Re: [linux-pm] [PATCH 0/8] Suspend block api (version 8)

Felipe Balbi
2010-05-27T17:17:29Z

On Thu, May 27, 2010 at 07:04:24PM +0200, ext Alan Stern wrote:
>On Thu, 27 May 2010, Felipe Balbi wrote:
>
>> On Thu, May 27, 2010 at 05:06:23PM +0200, ext Alan Stern wrote:
>> >If people don't mind, here is a greatly simplified summary of the
>> >comments and objections I have seen so far on this thread:
>> >
>> > The in-kernel suspend blocker implementation is okay, even
>> > beneficial.
>>
>> I disagree here. I believe expressing that as QoS is much better. Let
>> the kernel decide which power state is better as long as I can say I
>> need 100us IRQ latency or 100ms wakeup latency.
>
>Does this mean you believe "echo mem >/sys/power/state" is bad and
>should be removed? Or "echo disk >/sys/power/state"? They pay no
>attention to latencies or other requirements.

no, not at all. I think they are also really useful. But I also think
in-kernel suspend blockers are unnecessary. I think runtime pm + cpuidle
+ cpufreq is well enough for all cases. We just need to give those three
information about desired latencies.

--
balbi

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