From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16695C433F5 for ; Sat, 4 Dec 2021 14:34:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233973AbhLDOhe (ORCPT ); Sat, 4 Dec 2021 09:37:34 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:49905 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229553AbhLDOhd (ORCPT ); Sat, 4 Dec 2021 09:37:33 -0500 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-267-MTGFJstEMMy1CY558vknEA-1; Sat, 04 Dec 2021 14:34:04 +0000 X-MC-Unique: MTGFJstEMMy1CY558vknEA-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.26; Sat, 4 Dec 2021 14:34:04 +0000 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.026; Sat, 4 Dec 2021 14:34:04 +0000 From: David Laight To: 'Subhashini Rao Beerisetty' , "linux-pci@vger.kernel.org" , LKML , kernelnewbies Subject: RE: latency Thread-Topic: latency Thread-Index: AQHX6GdhmNv7avsZu0CbwMJv9zlFaKwiXsGw Date: Sat, 4 Dec 2021 14:34:04 +0000 Message-ID: <3b914a515b1d4e749e58d3b46cf12b26@AcuMS.aculab.com> References: In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org RnJvbTogU3ViaGFzaGluaSBSYW8gQmVlcmlzZXR0eSA8c3ViaGFzaGJlZXJpc2V0dHlAZ21haWwu Y29tPg0KPiBTZW50OiAwMyBEZWNlbWJlciAyMDIxIDE3OjAxDQo+IA0KPiAgWyBQbGVhc2Uga2Vl cCBtZSBpbiBDQyBhcyBJJ20gbm90IHN1YnNjcmliZWQgdG8gdGhlIGxpc3RdDQo+IA0KPiBIaSBh bGwsDQo+IA0KPiBXZSBhcmUgdXNpbmcgdGhlIExpbnV4IE9TIG9uIGFuIHg4Nl82NCBtYWNoaW5l LiBJIG5lZWQgdG8gbWVhc3VyZSB0aGUNCj4gUENJZSBsYXRlbmN5IG9uIG15IHN5c3RlbSwgZG9l cyBrZXJuZWwgaGF2ZSBhbnkgbGF0ZW5jeSBtZWFzdXJlbWVudA0KPiBtb2R1bGUgZm9yIHRoZSBQ Q0llIGJ1cz8NCg0KU2xvd2VyIHRoYW4geW91IGV4cGVjdCA6LSkNCg0KV3JpdGVzIGFyZSBhc3lu Y2hyb25vdXMgc28gcmVhbGx5IG9ubHkgbGltaXRlZCBieSB0aGUgYWN0dWFsIHNwZWVkDQpvZiB0 aGUgUENJZSBsaW5rIGFuZCB0aGUgcmF0ZSB0aGUgc2xhdmUgY2FuIHByb2Nlc3MgdGhlbS4NClNv IHRoZSBhY3R1YWwgbGF0ZW5jeSBvZiB3cml0ZXMgZG9lc24ndCBtYXR0ZXIgYW5kIHRoZSB0aHJv dWdocHV0DQppcyByZWFzb25hYmxlLg0KDQpSZWFkcyBhcmUgbXVjaCBtb3JlIHByb2JsZW1hdGlj Lg0KV2hpbGUgdGhlIFBDSWUgYnVzIGFsbG93cyBtdWx0aXBsZSBvdXRzdGFuZGluZyByZWFkIHJl cXVlc3RzIHRoZQ0KSW50ZWwgeDg2IEkndmUgdGVzdGVkIHdpbGwgb25seSBnZW5lcmF0ZSBvbmUg b3V0c3RhbmRpbmcgcmVxdWVzdA0KZm9yIGVhY2ggY3B1IGNvcmUuDQpTbyBidWZmZXIgcmVhZHMg YXJlIHBhcnRpY3VsYXJseSBzbG93Lg0KDQpUaGUgZGVsYXlzIGJldHdlZW4gb24gcmVhZCBjb21w bGV0aW5nIGFuZCB0aGUgbmV4dCByZWFkIFRMUCBiZWluZw0Kc2VudCBhcmUgKHByb2JhYmx5KSBu ZWdsaWdpYmxlIGNvbXBhcmVkIHRvIHRoZSBvdGhlciBkZWxheXMuDQpTbyB0aGUgbGF0ZW5jeSBv ZiBhIHJlYWQgaXMganVzdCB0aGUgdGltZSB0aGUgdHdvIFRMUCB0YWtlIHRvDQpiZSB0cmFuc21p dHRlZCBvdmVyIHRoZSB3aXJlIChpbmNsdWRpbmcgZGVsYXlzIGZvciBQQ0llIGJyaWRnZXMpDQpw bHVzIHRoZSB0aW1lIHRoZSBzbGF2ZSB0YWtlcyB0byBnZW5lcmF0ZSB0aGUgcmVzcG9uc2UgVExQ Lg0KT24gdGhlIGZwZ2Egc2xhdmVzIHdlIGFyZSB1c2luZyB0aGF0IGlzIChmcm9tIG1lbW9yeSkg YWJvdXQgMTI4DQpjeWNsZXMgb2YgdGhlIDYyLjVNSHogY2xvY2sgLSBpZSBhYnNvbHV0ZWx5IGFn ZXMuDQoNCkZvciByZWFkcyB5b3UgZGVmaW5pdGVseSBuZWVkIHRvIHVzZSB0aGUgbGFyZ2VzdCBy ZWdpc3RlciBzaXplDQpwb3NzaWJsZSAtIGVhY2ggcmVhZCBpbnN0cnVjdGlvbiAoZXZlbiBtaXNh bGlnbmVkIG9uZXMpIGdlbmVyYXRlcw0KZXhhY3RseSBvbmUgcmVhZCBUTFAuDQoNCklmIHlvdSBh cmUgZGVzaWduaW5nIGFuIGludGVyZmFjZSBmb3IgYW4gZnBnYSB0aGVuIGNvbnNpZGVyIHVzaW5n DQp3cml0ZXMgZnJvbSBib3RoIHNpZGVzIGZvciBldmVyeXRoaW5nIGV4Y2VwdCBidWxrIGRhdGEu DQoNCllvdSBjYW4gKHByb2JhYmx5KSBtZWFzdXJlIHRoZSBsYXRlbmN5IG9mIHlvdXIgYWN0dWFs IHN5c3RlbSB1c2luZzoNCgl4ID0gcmR0c2MoKTsNCgl2ID0gcmVhZGwoKTsNCglsZmVuY2U7DQoJ ZWxhcHNlZCA9IHJkdHNjKCkgLSB4Ow0KSG93ZXZlciB0aGUgVFNDIHZhbHVlcyBkZXBlbmQgb24g dGhlIGN1cnJlbnQgY3B1IGZyZXF1ZW5jeSAod2hpY2gNCndpbGwgY2hhbmdlICdyYW5kb21seScp Lg0KT3IgcHV0IHRoZSByZWFkbCgpIGludG8gYSBsb29wIGFuZCBkbyBlbm91Z2ggdGhhdCB0aGUg aGlnaC1yZXMNCnN5c3RlbSB0aW1lIGRlbHRzIG1ha2VzIHNlbnNlLg0KDQoJRGF2aWQNCg0KLQ0K UmVnaXN0ZXJlZCBBZGRyZXNzIExha2VzaWRlLCBCcmFtbGV5IFJvYWQsIE1vdW50IEZhcm0sIE1p bHRvbiBLZXluZXMsIE1LMSAxUFQsIFVLDQpSZWdpc3RyYXRpb24gTm86IDEzOTczODYgKFdhbGVz KQ0K