linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Len Brown <lenb@kernel.org>
Cc: Trinabh Gupta <trinabh@linux.vnet.ibm.com>,
	arjan@linux.intel.com, peterz@infradead.org,
	suresh.b.siddha@intel.com, benh@kernel.crashing.org,
	venki@google.com, ak@linux.intel.com,
	linux-kernel@vger.kernel.org, sfr@canb.auug.org.au,
	xen-devel@lists.xensource.com
Subject: Re: [RFC PATCH V4 4/5] cpuidle: driver for xen
Date: Thu, 24 Mar 2011 08:05:22 -0400	[thread overview]
Message-ID: <20110324120522.GB29294@dumpdata.com> (raw)
In-Reply-To: <alpine.LFD.2.02.1103231659210.12911@x980>

On Thu, Mar 24, 2011 at 03:18:14AM -0400, Len Brown wrote:
> Is a CONFIG_XEN kernel supposed to use just HLT in idle?

For right now..
> 
> xen_arch_setup() does this:
> 
>         pm_idle = default_idle;
>         boot_option_idle_override = IDLE_HALT;
> 
> which has that effect.  I guess this makes sense b/c the
> CONFIG_XEN kernel is Dom0 and the real C-sates are done
> by the hypervisor?

Correct. There are some patches that make the C-states 
be visible in the Linux kernel, but that hasn't been ported
over yet.

> 
> Would the same CONFIG_XEN kernel binary ever not
> run xen_arch_setup(), run on raw hardware, and want

ever not? I am not sure of the question, so let me state:
The Linux kernel if compiled with CONFIG_XEN, and if run on
native hardware, would _never_ run 'xen_arch_setup()'*. It would
run the normal, native type setup.

> to use idle states other than HLT?
> 

*: It could if you really really wanted. You would need to change
the GRUB2 to inject some extra data in the 'sub_hardware' flag to be
the Xen specific.

  reply	other threads:[~2011-03-24 12:06 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-22 12:32 [RFC PATCH V4 0/5] cpuidle: Cleanup pm_idle and include driver/cpuidle.c in-kernel Trinabh Gupta
2011-03-22 12:32 ` [RFC PATCH V4 1/5] cpuidle: Remove pm_idle pointer for x86 Trinabh Gupta
2011-03-23  1:00   ` Stephen Rothwell
2011-03-23 10:10     ` Trinabh Gupta
2011-03-22 12:32 ` [RFC PATCH V4 2/5] cpuidle: list based cpuidle driver registration and selection Trinabh Gupta
2011-03-23  2:59   ` Len Brown
2011-03-23  9:22     ` Trinabh Gupta
2011-03-23 20:51       ` Len Brown
2011-03-24  4:41         ` Len Brown
2011-03-24 14:13         ` Trinabh Gupta
2011-03-24 16:52           ` Vaidyanathan Srinivasan
2011-03-25  7:13             ` Len Brown
2011-03-25  7:05           ` Len Brown
2011-03-25 15:35             ` [Xen-devel] " Konrad Rzeszutek Wilk
2011-03-31  2:25               ` Len Brown
2011-03-22 12:33 ` [RFC PATCH V4 3/5] cpuidle: default idle driver for x86 Trinabh Gupta
2011-03-23  3:13   ` Len Brown
2011-03-23  9:31     ` Trinabh Gupta
2011-03-24 16:32       ` Vaidyanathan Srinivasan
2011-03-22 12:33 ` [RFC PATCH V4 4/5] cpuidle: driver for xen Trinabh Gupta
2011-03-22 14:50   ` Konrad Rzeszutek Wilk
2011-03-23  9:57     ` Trinabh Gupta
2011-03-24  7:18       ` Len Brown
2011-03-24 12:05         ` Konrad Rzeszutek Wilk [this message]
2011-03-25  7:19           ` Len Brown
2011-03-25 14:43             ` [Xen-devel] " Jeremy Fitzhardinge
2011-03-25 14:38           ` Jeremy Fitzhardinge
2011-03-31  2:02             ` Len Brown
2011-03-31 21:26               ` Len Brown
2011-03-31 22:36                 ` Jeremy Fitzhardinge
2011-04-01  3:03                   ` Len Brown
2011-03-22 12:33 ` [RFC PATCH V4 5/5] cpuidle: cpuidle driver for apm Trinabh Gupta
2011-03-23  1:14   ` Stephen Rothwell
2011-03-23 10:25     ` Trinabh Gupta
2011-03-23 20:32       ` Len Brown
2011-03-24 14:28         ` Trinabh Gupta
2011-03-24 16:21           ` Vaidyanathan Srinivasan
2011-03-25  7:24           ` Len Brown
2011-03-25 18:01             ` Vaidyanathan Srinivasan
2011-03-31  2:17               ` cpuidle asymmetry (was Re: [RFC PATCH V4 5/5] cpuidle: cpuidle driver for apm) Len Brown
2011-03-31 13:18                 ` Peter Zijlstra
2011-04-01  4:09                   ` Len Brown
2011-04-01  8:15                     ` Dipankar Sarma
2011-04-01 14:38                       ` Arjan van de Ven
2011-04-03 16:18                         ` Dipankar Sarma
2011-04-01 14:02                     ` Peter Zijlstra
2011-04-04 14:32                       ` Dipankar Sarma
2011-04-05 15:01                         ` Peter Zijlstra
2011-04-05 15:48                           ` Dipankar Sarma
2011-04-01  7:02                 ` Trinabh Gupta
2011-03-24  4:27   ` [RFC PATCH V4 5/5] cpuidle: cpuidle driver for apm Len Brown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20110324120522.GB29294@dumpdata.com \
    --to=konrad.wilk@oracle.com \
    --cc=ak@linux.intel.com \
    --cc=arjan@linux.intel.com \
    --cc=benh@kernel.crashing.org \
    --cc=lenb@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=sfr@canb.auug.org.au \
    --cc=suresh.b.siddha@intel.com \
    --cc=trinabh@linux.vnet.ibm.com \
    --cc=venki@google.com \
    --cc=xen-devel@lists.xensource.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).