From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755051AbaIWKDi (ORCPT ); Tue, 23 Sep 2014 06:03:38 -0400 Received: from mail-bn1bon0115.outbound.protection.outlook.com ([157.56.111.115]:23264 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754283AbaIWKDg (ORCPT ); Tue, 23 Sep 2014 06:03:36 -0400 X-Greylist: delayed 891 seconds by postgrey-1.27 at vger.kernel.org; Tue, 23 Sep 2014 06:03:36 EDT From: Thomas Shao To: Olaf Hering CC: "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "driverdev-devel@linuxdriverproject.org" , "apw@canonical.com" , "jasowang@redhat.com" , "KY Srinivasan" , Haiyang Zhang Subject: RE: [PATCH] Drivers: hv: util: Implement Time Synchronization using host time sample Thread-Topic: [PATCH] Drivers: hv: util: Implement Time Synchronization using host time sample Thread-Index: AQHP1vKMtDPVAvlpRESa+FlYjIeumZwOWccAgAAXQzA= Date: Tue, 23 Sep 2014 09:47:59 +0000 Message-ID: References: <1411451081-13423-1-git-send-email-huishao@microsoft.com> <20140923075610.GA10933@aepfle.de> In-Reply-To: <20140923075610.GA10933@aepfle.de> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [141.251.55.4] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:131.107.125.37;CTRY:US;IPV:NLI;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10019020)(6009001)(438002)(189002)(13464003)(377454003)(199003)(24454002)(51704005)(64706001)(84676001)(77096002)(50986999)(85852003)(90102001)(4396001)(95666004)(76176999)(86362001)(20776003)(21056001)(47776003)(66066001)(99396002)(86612001)(54356999)(33656002)(87936001)(50466002)(86146001)(81156004)(106466001)(2656002)(81342003)(74502003)(46102003)(6806004)(77982003)(76482002)(80022003)(107046002)(79102003)(81542003)(74662003)(19580395003)(68736004)(55846006)(69596002)(83322001)(19580405001)(44976005)(110136001)(31966008)(83072002)(106116001)(92566001)(92726001)(23676002)(85306004)(120916001)(16796002)(10300001)(97736003);DIR:OUT;SFP:1102;SCL:1;SRVR:CY1PR0301MB1209;H:mail.microsoft.com;FPR:;MLV:sfv;PTR:InfoDomainNonexistent;MX:1;A:1;LANG:en; X-Microsoft-Antispam: UriScan:; X-Microsoft-Antispam: BCL:0;PCL:0;RULEID:;SRVR:CY1PR0301MB1209; X-O365ENT-EOP-Header: Message processed by - O365_ENT: Allow from ranges (Engineering ONLY) X-Forefront-PRVS: 0343AC1D30 Authentication-Results: spf=pass (sender IP is 131.107.125.37) smtp.mailfrom=huishao@microsoft.com; X-OriginatorOrg: microsoft.onmicrosoft.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id s8NA3hnx003177 > -----Original Message----- > From: Olaf Hering [mailto:olaf@aepfle.de] > Sent: Tuesday, September 23, 2014 3:56 PM > To: Thomas Shao > Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; > driverdev-devel@linuxdriverproject.org; apw@canonical.com; > jasowang@redhat.com; KY Srinivasan; Haiyang Zhang > Subject: Re: [PATCH] Drivers: hv: util: Implement Time Synchronization using > host time sample > > On Tue, Sep 23, Thomas Shao wrote: > > > In current hyper-v time sync service,it only gets the initial clock > > time from the host. It didn't process the following time samples. This > > change introduced a module parameter called host_time_sync. If it is > > set to true, the guest will periodically sychronize it's time with the > > host clock using host time sample. By default it is disabled, because > > we still recommend user to configure NTP for time synchronization. > > Is that new knob a temporary thing to aid testing and development? > Because once it sneaks in it becomes some sort of ABIT. > So if the outcome of all that is that 'sync with host every once in a while' will be > the default, the new knob is not required. > Hi Olaf, If the guest is configured with other time sync source, like NTP, we don't want the guest to periodically sync with host. This feature is useful when the guest didn't have Internet connection to setup NTP. So the new knob is to allow users to only turn on the host-guest sync when they need. Regards Thomas > Olaf {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Thomas Shao Subject: RE: [PATCH] Drivers: hv: util: Implement Time Synchronization using host time sample Date: Tue, 23 Sep 2014 09:47:59 +0000 Message-ID: References: <1411451081-13423-1-git-send-email-huishao@microsoft.com> <20140923075610.GA10933@aepfle.de> In-Reply-To: <20140923075610.GA10933@aepfle.de> Content-Language: en-US Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 List-ID: To: Olaf Hering Cc: "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "driverdev-devel@linuxdriverproject.org" , "apw@canonical.com" , "jasowang@redhat.com" , KY Srinivasan , Haiyang Zhang DQo+IC0tLS0tT3JpZ2luYWwgTWVzc2FnZS0tLS0tDQo+IEZyb206IE9sYWYgSGVyaW5nIFttYWls dG86b2xhZkBhZXBmbGUuZGVdDQo+IFNlbnQ6IFR1ZXNkYXksIFNlcHRlbWJlciAyMywgMjAxNCAz OjU2IFBNDQo+IFRvOiBUaG9tYXMgU2hhbw0KPiBDYzogZ3JlZ2toQGxpbnV4Zm91bmRhdGlvbi5v cmc7IGxpbnV4LWtlcm5lbEB2Z2VyLmtlcm5lbC5vcmc7DQo+IGRyaXZlcmRldi1kZXZlbEBsaW51 eGRyaXZlcnByb2plY3Qub3JnOyBhcHdAY2Fub25pY2FsLmNvbTsNCj4gamFzb3dhbmdAcmVkaGF0 LmNvbTsgS1kgU3Jpbml2YXNhbjsgSGFpeWFuZyBaaGFuZw0KPiBTdWJqZWN0OiBSZTogW1BBVENI XSBEcml2ZXJzOiBodjogdXRpbDogSW1wbGVtZW50IFRpbWUgU3luY2hyb25pemF0aW9uIHVzaW5n DQo+IGhvc3QgdGltZSBzYW1wbGUNCj4gDQo+IE9uIFR1ZSwgU2VwIDIzLCBUaG9tYXMgU2hhbyB3 cm90ZToNCj4gDQo+ID4gSW4gY3VycmVudCBoeXBlci12IHRpbWUgc3luYyBzZXJ2aWNlLGl0IG9u bHkgZ2V0cyB0aGUgaW5pdGlhbCBjbG9jaw0KPiA+IHRpbWUgZnJvbSB0aGUgaG9zdC4gSXQgZGlk bid0IHByb2Nlc3MgdGhlIGZvbGxvd2luZyB0aW1lIHNhbXBsZXMuIFRoaXMNCj4gPiBjaGFuZ2Ug aW50cm9kdWNlZCBhIG1vZHVsZSBwYXJhbWV0ZXIgY2FsbGVkIGhvc3RfdGltZV9zeW5jLiBJZiBp dCBpcw0KPiA+IHNldCB0byB0cnVlLCB0aGUgZ3Vlc3Qgd2lsbCBwZXJpb2RpY2FsbHkgc3ljaHJv bml6ZSBpdCdzIHRpbWUgd2l0aCB0aGUNCj4gPiBob3N0IGNsb2NrIHVzaW5nIGhvc3QgdGltZSBz YW1wbGUuIEJ5IGRlZmF1bHQgaXQgaXMgZGlzYWJsZWQsIGJlY2F1c2UNCj4gPiB3ZSBzdGlsbCBy ZWNvbW1lbmQgdXNlciB0byBjb25maWd1cmUgTlRQIGZvciB0aW1lIHN5bmNocm9uaXphdGlvbi4N Cj4gDQo+IElzIHRoYXQgbmV3IGtub2IgYSB0ZW1wb3JhcnkgdGhpbmcgdG8gYWlkIHRlc3Rpbmcg YW5kIGRldmVsb3BtZW50Pw0KPiBCZWNhdXNlIG9uY2UgaXQgc25lYWtzIGluIGl0IGJlY29tZXMg c29tZSBzb3J0IG9mIEFCSVQuDQo+IFNvIGlmIHRoZSBvdXRjb21lIG9mIGFsbCB0aGF0IGlzIHRo YXQgJ3N5bmMgd2l0aCBob3N0IGV2ZXJ5IG9uY2UgaW4gYSB3aGlsZScgd2lsbCBiZQ0KPiB0aGUg ZGVmYXVsdCwgdGhlIG5ldyBrbm9iIGlzIG5vdCByZXF1aXJlZC4NCj4gDQoNCkhpIE9sYWYsIA0K SWYgdGhlIGd1ZXN0IGlzIGNvbmZpZ3VyZWQgd2l0aCBvdGhlciB0aW1lIHN5bmMgc291cmNlLCBs aWtlIE5UUCwgd2UgZG9uJ3Qgd2FudCB0aGUgDQpndWVzdCB0byBwZXJpb2RpY2FsbHkgc3luYyB3 aXRoIGhvc3QuIFRoaXMgZmVhdHVyZSBpcyB1c2VmdWwgd2hlbiB0aGUgZ3Vlc3QgZGlkbid0IGhh dmUNCkludGVybmV0IGNvbm5lY3Rpb24gdG8gc2V0dXAgTlRQLiBTbyB0aGUgbmV3IGtub2IgaXMg dG8gYWxsb3cgdXNlcnMgdG8gb25seSB0dXJuIG9uIHRoZQ0KaG9zdC1ndWVzdCBzeW5jIHdoZW4g dGhleSBuZWVkLg0KDQpSZWdhcmRzDQpUaG9tYXMNCg0KPiBPbGFmDQo=