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-tools

Re: [Xen-tools] hi, all. I have a question about xentrace?

To: xen-tools@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-tools] hi, all. I have a question about xentrace?
From: Mark Williamson <mark.williamson@xxxxxxxxxxxx>
Date: Thu, 22 Mar 2007 16:20:57 +0000
Cc: 宋懿gmail <sjtusongyi@xxxxxxxxx>
Delivery-date: Thu, 22 Mar 2007 09:18:04 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <e2a5d9ae0703212321w4ae2c278w9aac0d0616ed9ff5@xxxxxxxxxxxxxx>
List-help: <mailto:xen-tools-request@lists.xensource.com?subject=help>
List-id: Xen control tools developers <xen-tools.lists.xensource.com>
List-post: <mailto:xen-tools@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-tools>, <mailto:xen-tools-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-tools>, <mailto:xen-tools-request@lists.xensource.com?subject=unsubscribe>
References: <e2a5d9ae0703212321w4ae2c278w9aac0d0616ed9ff5@xxxxxxxxxxxxxx>
Sender: xen-tools-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.9.5
> as we all known, xentrace is a lightweight event logging facility present
> in Xen. XenTrace
> can log events at arbitrary control points in the hypervisor.
> my question is that which API or interface does Xen provide to xentrace?
> what is the principle of xentrace? how does the event logged into trace
> buffer?
>
> I had read xentrace.c file; but found no result.

You also need to read xen/common/trace.c and xen/include/xen/trace.h and 
xen/include/public/trace.h

Tracepoints are written into the Xen source code and compiled in.  These use 
the macros in xen/include/xen/trace.h - these cause data to be queued into 
per-CPU buffers that are shared with domain 0.

xentrace.c contains the code for mapping these buffers and reading their 
contents, which are then dumped out to a file.  xentrace_format parses this 
data and prints it out in a readable form.

Cheers,
Mark

-- 
Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
Mark: To answer a question with a question: What use is a skateboard?
Dave: Skateboards have wheels.
Mark: My wheel has a wheel!

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

<Prev in Thread] Current Thread [Next in Thread>