[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Xen-devel] emulated tsc and frequency info
- To: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
- From: Juergen Gross <juergen.gross@xxxxxxxxxxxxxx>
- Date: Tue, 20 Jul 2010 11:20:37 +0200
- Delivery-date: Tue, 20 Jul 2010 02:21:43 -0700
- Dkim-signature: v=1; a=rsa-sha256; c=simple/simple; d=ts.fujitsu.com; i=juergen.gross@xxxxxxxxxxxxxx; q=dns/txt; s=s1536b; t=1279617750; x=1311153750; h=message-id:date:from:mime-version:to:subject: content-transfer-encoding; z=Message-ID:=20<4C456A65.2020100@xxxxxxxxxxxxxx>|Date:=20 Tue,=2020=20Jul=202010=2011:20:37=20+0200|From:=20Juergen =20Gross=20<juergen.gross@xxxxxxxxxxxxxx>|MIME-Version: =201.0|To:=20"xen-devel@xxxxxxxxxxxxxxxxxxx"=20<xen-devel @lists.xensource.com>|Subject:=20emulated=20tsc=20and=20f requency=20info|Content-Transfer-Encoding:=207bit; bh=mUjwcALYtuPvv3YzSDhDKahMzfK9wPoy2267oJzo/v0=; b=I3wR7LGhoZdKvIYGvgh3fRQllrj7jD4t82hTFnPXxJxbptR8ABX0h5M5 301ycBIusZVIyXCC0YOt80JBDiF5tw8I5iDIFxXSs9tN1zeRjhwIVBudL SuxnirdTPp5qlaL85Kuohk+KPNdoIjWvB80VIIR4/OB66QXMkfSzdDbMM NYsU5Ym2JE+3oYK2pK9l7eWR+nIOtavle+52xqWsmewH18ZQ95A5Y3Pm4 FC40i/uUCTxRkiug0d7G88dLTyvPc;
- Domainkey-signature: s=s1536a; d=ts.fujitsu.com; c=nofws; q=dns; h=X-SBRSScore:X-IronPort-AV:Received:X-IronPort-AV: Received:Received:Message-ID:Date:From:Organization: User-Agent:MIME-Version:To:Subject:Content-Type: Content-Transfer-Encoding; b=UbXotHa4xnPF5WJ5ECgMks3Co4CQUyoQF62T1QIoTwrjY8HA1aEomN0n j5LkeVcEig9bFf+d17yayxPv3sVXsA4sKLBMWA4F62YjfDgRzqvCKEQpy gHqHNNUqu/3N9cAa+u2Elchkh/3aUzuIHLstZBdBpav2LM2uAg0yoR2jZ qvU1bRd2BH2CJz87uGqtwzckDnV+H3xcc8tm0/26VQeXq9I8KRnKBPI3O AsPBg5MMSDuAbDT276+Oyf2OTBLi1;
- List-id: Xen developer discussion <xen-devel.lists.xensource.com>
Hi,
with xen 4.0 and xen-unstable I see weird tsc information in my HVM-domain
with PV-driver, if xen chooses to emulate tsc (d->arch.vtsc is set):
In the shared info page the tsc_to_system_mul is still reflecting the host
cpu frequency instead of the emulated 1 GHz.
The reason is quite simple: tsc_set_info() is never called with a gtsc_khz
value other than 0. I wonder which solution is the correct one:
- if tsc_set_info() is called with gtsc_khz=0, assume 1 GHz (my favorite).
- don't use 0 as default value for gtsc_khz when calling tsc_set_info()
(this would require changes in the tools, too).
- let the domU check the vtsc-flag in cpuid-info and assume 1 GHz then (very
ugly in my opinion).
Any thoughts?
Juergen
--
Juergen Gross Principal Developer Operating Systems
TSP ES&S SWE OS6 Telephone: +49 (0) 89 3222 2967
Fujitsu Technology Solutions e-mail: juergen.gross@xxxxxxxxxxxxxx
Domagkstr. 28 Internet: ts.fujitsu.com
D-80807 Muenchen Company details: ts.fujitsu.com/imprint.html
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel