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 X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C796EC433B4 for ; Tue, 13 Apr 2021 15:06:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93581613B7 for ; Tue, 13 Apr 2021 15:06:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346456AbhDMPG0 (ORCPT ); Tue, 13 Apr 2021 11:06:26 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.85.151]:21628 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242462AbhDMPGZ (ORCPT ); Tue, 13 Apr 2021 11:06:25 -0400 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-228-VDU7HPf7PQSHs4NDsnQDhw-1; Tue, 13 Apr 2021 16:06:01 +0100 X-MC-Unique: VDU7HPf7PQSHs4NDsnQDhw-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 15.0.1497.2; Tue, 13 Apr 2021 16:06:00 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.012; Tue, 13 Apr 2021 16:06:00 +0100 From: David Laight To: 'Mathieu Desnoyers' , Peter Zijlstra CC: Eric Dumazet , Ingo Molnar , paulmck , Boqun Feng , Arjun Roy , linux-kernel , "Eric Dumazet" Subject: RE: [PATCH 3/3] rseq: optimise for 64bit arches Thread-Topic: [PATCH 3/3] rseq: optimise for 64bit arches Thread-Index: AQHXMETc4NN4/ddyHEK6qBKOxo8eAaqyQOlAaWt3qjT8tO0Y8A== Date: Tue, 13 Apr 2021 15:06:00 +0000 Message-ID: <56c227c1defe4b9ca9c6a75537234e20@AcuMS.aculab.com> References: <20210413073657.2308450-1-eric.dumazet@gmail.com> <20210413073657.2308450-4-eric.dumazet@gmail.com> <644332839.71291.1618323708305.JavaMail.zimbra@efficios.com> In-Reply-To: <644332839.71291.1618323708305.JavaMail.zimbra@efficios.com> 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-kernel@vger.kernel.org RnJvbTogTWF0aGlldSBEZXNub3llcnMgPG1hdGhpZXUuZGVzbm95ZXJzQGVmZmljaW9zLmNvbT4N Cj4gU2VudDogMTMgQXByaWwgMjAyMSAxNToyMg0KLi4uDQo+ID4JRGF2aWQNCj4gPg0KPiA+PiBT byBJIHN1cHBvc2UgdGhhdCBpZiB3ZSdyZSBnb2luZyB0byAjaWZkZWYgdGhpcywgd2UgbWlnaHQg YXMgd2VsbCBkbyB0aGUNCj4gPj4gd2hvbGUgdGhpbmcuDQo+ID4+DQo+ID4+IE1hdGhpZXU7IGRp ZCBJIGZvcmdldCBhIHJlYXNvbiB3aHkgdGhpcyBjYW5ub3Qgd29yaz8NCj4gDQo+IFRoZSBvbmx5 IGRpZmZlcmVuY2UgaXQgYnJpbmdzIG9uIDMyLWJpdCBpcyB0aGF0IHRoZSB0cnVuY2F0aW9uIG9m IGhpZ2ggYml0cw0KPiB3aWxsIGJlIGRvbmUgYmVmb3JlIHRoZSBmb2xsb3dpbmcgdmFsaWRhdGlv bjoNCj4gDQo+ICAgICAgICAgaWYgKCFwdHIpIHsNCj4gICAgICAgICAgICAgICAgIG1lbXNldChy c2VxX2NzLCAwLCBzaXplb2YoKnJzZXFfY3MpKTsNCj4gICAgICAgICAgICAgICAgIHJldHVybiAw Ow0KPiAgICAgICAgIH0NCj4gICAgICAgICBpZiAocHRyID49IFRBU0tfU0laRSkNCj4gICAgICAg ICAgICAgICAgIHJldHVybiAtRUlOVkFMOw0KPiANCj4gVGhlIHF1ZXN0aW9uIGlzIHdoZXRoZXIg d2UgcmVhbGx5IHdhbnQgdG8gaXNzdWUgYSBzZWdtZW50YXRpb24gZmF1bHQgaWYgMzItYml0DQo+ IHVzZXItc3BhY2UgaGFzIHNldCBub24temVybyBoaWdoIGJpdHMsIG9yIGlmIHNpbGVudGx5IGln bm9yaW5nIHRob3NlIGhpZ2gNCj4gYml0cyBpcyBhY2NlcHRhYmxlLg0KDQpXZWxsLCAzMmJpdCBw cm9ncmFtcyBydW5uaW5nIG9uIDY0Yml0IGtlcm5lbHMgYmV0dGVyIHplcm8gdGhlICdwYWRkaW5n Jy4NCg0KSXQgaXMgYSBzaGFtZSB0aGF0IHRoZSAzMmJpdCBjb21waWxlcnMgZG9uJ3QgaGF2ZSBh biBhdHRyaWJ1dGUoNjRiaXQpDQpmb3IgcG9pbnRlcnMuDQoNCj4gLi4uDQo+IEkgYW0gYWx3YXlz IHJlbHVjdGFudCB0byB1c2UgbG9uZy91bnNpZ25lZCBsb25nIHR5cGUgYXMgdHlwZSBmb3IgdGhl IGdldC9wdXRfdXNlcg0KPiAoeCkgYXJndW1lbnQsIGJlY2F1c2UgaXQgaGlkZXMgdGhlIGNhc3Qg ZGVlcCB3aXRoaW4gYXJjaGl0ZWN0dXJlLXNwZWNpZmljIG1hY3Jvcy4NCj4gSSB1bmRlcnN0YW5k IHRoYXQgaW4gdGhpcyBzcGVjaWZpYyBjYXNlIGl0IGhhcHBlbnMgdGhhdCBvbiA2NC1iaXQgYXJj aHMgd2UgZW5kIHVwDQo+IGNhc3RpbmcgYSB1NjQgdG8gdW5zaWduZWQgbG9uZyAoc2FtZSBzaXpl KSwgYW5kIG9uIDMyLWJpdCBhcmNocyB3ZSBlbmQgdXAgY2FzdGluZyBhDQo+IHUzMiB0byB1bnNp Z25lZCBsb25nIChhbHNvIHNhbWUgc2l6ZSksIHNvIHRoZXJlIGlzIG5vIHByYWN0aWNhbCBjb25j ZXJuIGFib3V0IHR5cGUNCj4gcHJvbW90aW9uIGFuZCBzaWduLWV4dGVuc2lvbiwgYnV0IEkgdGhp bmsgaXQgd291bGQgYmUgYmV0dGVyIHRvIGhhdmUgc29tZXRoaW5nDQo+IGV4cGxpY2l0LCBlLmcu Og0KDQpJZiB0aGUgQUJJIHBhc3NlcyBzbWFsbCBzdHJ1Y3R1cmVzIGluIHJlZ2lzdGVycyAobW9z dCBtb2Rlcm4gb25lcykNCnRoZW4gdXNlciBwb2ludGVycyBwcm9iYWJseSBvdWdodCB0byBiZSBl bmNhcHN1bGF0ZWQgaW4gYSBzdHJ1Y3R1cmUuDQpQb3NzaWJseSBhcyBhIHBvaW50ZXIgdG8gYW4g dW5rbm93biBzdHJ1Y3R1cmUuDQpUaGF0IHdvdWxkIGZvcmNlIGFsbCB0aGUgcmVxdWlyZWQgdHlw ZSBjaGVja2luZy4NClVuZm9ydHVuYXRlbHkgdGhlIGZhbGxvdXQvY2h1cm4gd291bGQgYmUgbWFz c2l2ZS4NCg0KPiAjaWZkZWYgQ09ORklHXzY0QklUDQo+IHN0YXRpYyBpbnQgcnNlcV9nZXRfY3Nf cHRyKHN0cnVjdCByc2VxX2NzIF9fdXNlciAqKnVwdHJwLCBzdHJ1Y3QgcnNlcV9jcyAqcnNlcV9j cykNCj4gew0KPiAgICAgdTY0IHB0cjsNCj4gDQo+ICAgICBpZiAoZ2V0X3VzZXIocHRyLCAmcnNl cV9jcy0+cHRyNjQpKQ0KPiAgICAgICAgIHJldHVybiAtRUZBVUxUOw0KPiAgICAgKnB0cnAgPSAo c3RydWN0IHJzZXFfY3MgX191c2VyICopcHRyOw0KPiAgICAgcmV0dXJuIDA7DQo+IH0NCj4gI2Vs c2UNCj4gc3RhdGljIGludCByc2VxX2dldF9jc19wdHIoc3RydWN0IHJzZXFfY3MgX191c2VyICoq dXB0cnAsIHN0cnVjdCByc2VxX2NzICpyc2VxX2NzKQ0KPiB7DQo+ICAgICB1MzIgcHRyOw0KPiAN Cj4gICAgIGlmIChnZXRfdXNlcihwdHIsICZyc2VxX2NzLT5wdHIucHRyMzIpKQ0KPiAgICAgICAg IHJldHVybiAtRUZBVUxUOw0KPiAgICAgKnB0cnAgPSAoc3RydWN0IHJzZXFfY3MgX191c2VyICop cHRyOw0KPiAgICAgcmV0dXJuIDA7DQo+IH0NCj4gI2VuZGlmDQoNCkhtbW0uLi4gdG9vIG11Y2gg cmVwbGljYXRpb24uDQpZb3UgY291bGQgZG86DQojaWZkZWYgQ09ORklHXzY0QklUDQojZGVmaW5l IFBUUl9UWVBFIHU2NA0KI2RlZmluZSBQVFJfRkxEIHB0cjY0DQojZWxzZQ0KI2RlZmluZSBQVFJf VFlQRSB1MzINCiNkZWZpbmUgUFRSX0ZMRCBwdHIzMg0KI2VuZGlmDQoNClRoZW4gaGF2ZSBvbmUg Y29weSBvZiB0aGUgY29kZSBhbmQgdGhlICN1bmRlZnMuDQouLi4NCg0KCURhdmlkDQoNCi0NClJl Z2lzdGVyZWQgQWRkcmVzcyBMYWtlc2lkZSwgQnJhbWxleSBSb2FkLCBNb3VudCBGYXJtLCBNaWx0 b24gS2V5bmVzLCBNSzEgMVBULCBVSw0KUmVnaXN0cmF0aW9uIE5vOiAxMzk3Mzg2IChXYWxlcykN Cg==