linux-kernel - Re: [linux-pm] [PATCH] - race-free suspend. Was: Re: [PATCH 0/8] Suspend block api (version 8)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <AANLkTinbLQNRyDC2PRUwoVXMF16RLHa2xZl3gJr-ftgB@mail.gmail.com>
Date:	Thu, 3 Jun 2010 10:26:58 -0700
From:	Brian Swetland <swetland@...gle.com>
To:	markgross@...gnar.org
Cc:	Neil Brown <neilb@...e.de>, Peter Zijlstra <peterz@...radead.org>,
	"Paul@...p1.linux-foundation.org" <Paul@...p1.linux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Florian Mickler <florian@...kler.org>,
	James Bottomley <James.Bottomley@...e.de>,
	Linux PM <linux-pm@...ts.linux-foundation.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Linux OMAP Mailing List <linux-omap@...r.kernel.org>,
	Felipe Balbi <felipe.balbi@...ia.com>,
	Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: Re: [linux-pm] [PATCH] - race-free suspend. Was: Re: [PATCH 0/8] 
	Suspend block api (version 8)

On Thu, Jun 3, 2010 at 6:36 AM, mark gross <640e9920@...il.com> wrote:
> On Wed, Jun 02, 2010 at 11:12:39PM -0700, Brian Swetland wrote:
>> On Wed, Jun 2, 2010 at 11:04 PM, mark gross <640e9920@...il.com> wrote:
>> >>
>> >> There are many wakeup events possible in a typical system --
>> >> keypresses or other input events, network traffic, telephony events,
>> >> media events (fill audio buffer, fill video decoder buffer, etc), and
>> >> I think requiring that all wakeup event processing bottleneck through
>> >> a single userspace process is non-optimal here.
>> >
>> > Um doesn't the android framework bottleneck the user mode lock
>> > processing through the powermanager and any wake up event processing
>> > eventually has to grab a lock through this bottleneck anyway?
>>
>> For "high level" framework/application level wakelocks, yes, but lower
>> level components beneath the java api layer use the kernel interface
>> directly.
>>
> Oh.  I thought everything went through
> hardware/libhardware_legacy/power/power.c
> who else is hitting /sys/power/* in the android user mode then?

I believe everything does -- that's the thin wrapper around the kernel
interface (which will have to change slightly to meet the
suspend_blocker device/fd vs wakelock proc/sys interface, etc), which
is used by the powermanager service, the RIL, and any other low level
code.  At the App/Service level, wakelocks are provided by a java
level API that is a remote interface to the powermanager.

Brian
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/