linux-kernel - Re: [PATCH 0/2] Run callback of device

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: <1370652132.4432.68.camel@ymzhang.sh.intel.com>
Date:	Sat, 08 Jun 2013 08:42:12 +0800
From:	Yanmin Zhang <yanmin_zhang@...ux.intel.com>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
Cc:	shuox.liu@...el.com, linux-kernel@...r.kernel.org,
	linux-pm@...r.kernel.org, pavel@....cz, len.brown@...el.com,
	gregkh@...uxfoundation.org
Subject: Re: [PATCH 0/2] Run callback of device_prepare/complete consistently

On Fri, 2013-06-07 at 12:36 +0200, Rafael J. Wysocki wrote:
> On Friday, June 07, 2013 04:20:30 PM shuox.liu@...el.com wrote:
> > dpm_run_callback is used in other stages of power states changing.
> > It provides debug info message and time measurement when call these
> > callback. We also want to benefit ->prepare and ->complete.
> > 
> > [PATCH 1/2] PM: use dpm_run_callback in device_prepare
> > [PATCH 2/2] PM: add dpm_run_callback_void and use it in device_complete
> 
> Is this an "Oh, why don't we do that?" series, or is it useful for anything
> in practice?  I'm asking, because we haven't added that stuff to start with
> since we didn't see why it would be useful to anyone.
> 
> And while patch [1/2] reduces the code size (by 1 line), so I can see some
> (tiny) benefit from applying it, patch [2/2] adds more code and is there any
> paractical reason?
Sometimes, suspend-to-ram path spends too much time (either suspend slowly
or wakeup slowly) and we need optimize it.
With the 2 patches, we could collect initcall_debug printk info and manually
check what prepare/complete callbacks consume too much time.

Thanks,
Yanmin


--
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/