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

From: Felipe Contreras
Date: Sat Jun 05 2010 - 15:53:57 EST


On Sat, Jun 5, 2010 at 10:04 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote:
> On Saturday 05 June 2010, Felipe Contreras wrote:
>> On Mon, May 31, 2010 at 11:47 PM, Florian Mickler <florian@xxxxxxxxxxx> wrote:
>> > On Mon, 31 May 2010 22:12:19 +0200
>> > Florian Mickler <florian@xxxxxxxxxxx> wrote:
>> >> If I have a simple shell script then I don't wanna jump through
>> >> hoops just to please your fragile kernel.
>> >
>> > Also why should that code on one device kill my uptime and on the
>> > other machine (my wall-plugged desktop) work just well? That doesn't
>> > sound right.
>>
>> Sounds perfectly right to me; one code runs perfectly fine on one
>> machine, and on the other doesn't even compile. Well, sure, it wasn't
>> written with that use-case in mind.
>>
>> > Clearly opportunistic suspend is a workaround for battery-driven devices
>> > and no general solution. But it is not specific to android. At least
>> > not inherently. It could be useful for any embedded or mobile device
>> > where you can clearly distinguish important functions from convenience
>> > functions.
>>
>> Yes, it could, but why go for the hacky solution when we know how to
>> achieve the ideal one?
>>
>> > I really can't understand the whole _fundamental_ opposition to this
>> > design choice.
>>
>> Nobody is using it, except Android. Nobody will use it, except Android.
>
> That's like saying "Android is not a legitimate user of the kernel". ÂIs that
> you wanted to say?

Read the context: opportunistic suspend, which is considered a
workaround, which requires new user-space API for suspend blockers,
might be remotely considered for inclusion *if* it indeed solves a
problem for battery-driven devices, which other parties also
experience and could benefit from this solution.

The answer: no, it doesn't: only Android user-space will benefit from it.

>> I have seen recent proposals that don't require changing the whole
>> user-space. That might actually be used by other players.
>
> Sure, an approach benefitting more platforms than just Android would be better,
> but saying that the kernel shouldn't address the Android's specific needs as a
> rule if no one else has those needs too is quite too far reaching to me.

There are no Android specific needs, why should certain user-space
ecosystem need certain API that somehow *nobody* else does? I think in
this huge thread it has become obvious that people are reluctant to
this idea... whatever problem Android user-space presents (I don't
think there's any), it can be solved for "he rest of the world" too,
and such generic solution is worth exploring.

--
Felipe Contreras
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