WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] ring buffer overflow

To: David Xu <davidxu06@xxxxxxxxx>
Subject: Re: [Xen-devel] ring buffer overflow
From: Ian Campbell <Ian.Campbell@xxxxxxxxxx>
Date: Fri, 7 Oct 2011 17:50:41 +0100
Cc: xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Fri, 07 Oct 2011 09:51:16 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <CAGjowiTvPu4KFTeLLCVUvoRombjXGscVWAgHLNi6+T7uQs2jPA@xxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Organization: Citrix Systems, Inc.
References: <CAGjowiTc0NAJbWR-RxwLTrz+bhbAFfvcPKPAB_F8r1ef6__PbA@xxxxxxxxxxxxxx> <1317368064.26672.198.camel@xxxxxxxxxxxxxxxxxxxxxx> <CAGjowiQE_3gTJxK+Ja850QU9g1+97hZ8hAgdv_a4B18jxmCNGw@xxxxxxxxxxxxxx> <1317393663.26672.288.camel@xxxxxxxxxxxxxxxxxxxxxx> <CAGjowiSrPCY50-iBK67nGfOGdK7z1htc58ohtrqJtmutmRRQzQ@xxxxxxxxxxxxxx> <1317394559.26672.293.camel@xxxxxxxxxxxxxxxxxxxxxx> <CAGjowiSkwN9Oz-qevYk2G1NgwBmFOLWFLtT30aBu0SAe=jqtog@xxxxxxxxxxxxxx> <CAGjowiSQO_Hzdbz0FxQK_7ppr-yvBSWYVbzoSUd_RfiWytZKPw@xxxxxxxxxxxxxx> <1318002580.21903.361.camel@xxxxxxxxxxxxxxxxxxxxxx> <CAGjowiTvPu4KFTeLLCVUvoRombjXGscVWAgHLNi6+T7uQs2jPA@xxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
On Fri, 2011-10-07 at 17:23 +0100, David Xu wrote:
> Hi,
> 
> This time I want to call it in the user-space. I wrote a user-level
> application and call the xc_sched_credit_domain_set( int
>  xc_handle, uint32_t domid, struct xen_domctl_sched_credit *sdom) in
> it. But I don't know how to pass the xc_handle parameter in this
> function. Thanks.

Tim already answered this. But why do you persist in top posting? You've
been asked not to _repeatedly_.

Please re-read http://wiki.xen.org/xenwiki/AskingXenDevelQuestions. In
particular the etiquette section.

Perhaps I should start ignoring top posted emails. :-/

Ian.

> 
> Regards,
> Cong
> 
> 2011/10/7 Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx>:
> > Stop top posting, I've asked you this before.
> >
> > On Fri, 2011-10-07 at 16:23 +0100, David Xu wrote:
> >> Hi,
> >>
> >> I want to use the libxc function xc_sched_credit_domain_set( int
> >> xc_handle, uint32_t domid, struct xen_domctl_sched_credit *sdom) in a
> >> user-level application. But I don't know how to set the value of
> >> xc_handle. Is there somebody familiar with it? Thanks.
> >
> > You can't use xc_* functions in the kernel, they are userspace. You
> > could in theory look at the implementation of xc_sched_credit_domain_set
> > to find out what that hypercall is and make the underlying hypercall
> > instead, But:
> >
> > The hypercall in question here is a domctl which are not available /
> > allowed from kernel space (for policy and semantic reasons rather than
> > technological ones).
> >
> > As I explained elsewhere I don't think the architecture you have in mind
> > is correct. I think you should look at exporting the necessary
> > statistics from the kernel to userspace and have a daemon implement the
> > logic and mechanisms for changing the scheduling parameters as required.
> >
> > Ian.
> >
> >
> >



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel