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[23.128.96.18]) by mx.google.com with ESMTP id y23si895183ejc.508.2020.12.15.06.00.04; Tue, 15 Dec 2020 06:00:29 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=aculab.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729027AbgLON4t (ORCPT + 99 others); Tue, 15 Dec 2020 08:56:49 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:43062 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727093AbgLON4D (ORCPT ); Tue, 15 Dec 2020 08:56:03 -0500 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-256-kyP4j1eZN0iEOkzo-w1qBQ-1; Tue, 15 Dec 2020 13:54:22 +0000 X-MC-Unique: kyP4j1eZN0iEOkzo-w1qBQ-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Tue, 15 Dec 2020 13:54:17 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Tue, 15 Dec 2020 13:54:17 +0000 From: David Laight To: 'Pavel Begunkov' , "linux-block@vger.kernel.org" CC: Jens Axboe , Christoph Hellwig , Matthew Wilcox , Ming Lei , Johannes Weiner , Alexander Viro , "Darrick J . Wong" , "Martin K . Petersen" , Jonathan Corbet , "linux-xfs@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "io-uring@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "target-devel@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "linux-doc@vger.kernel.org" Subject: RE: [PATCH v1 2/6] iov_iter: optimise bvec iov_iter_advance() Thread-Topic: [PATCH v1 2/6] iov_iter: optimise bvec iov_iter_advance() Thread-Index: AQHW0njgRO60UNrAz0qHNwIRx20dYqn35EKAgAAgPwCAACb+4A== Date: Tue, 15 Dec 2020 13:54:16 +0000 Message-ID: References: <5c9c22dbeecad883ca29b31896c262a8d2a77132.1607976425.git.asml.silence@gmail.com> <262132648a8f4e7a9d1c79003ea74b3f@AcuMS.aculab.com> 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-kernel@vger.kernel.org RnJvbTogUGF2ZWwgQmVndW5rb3YNCj4gU2VudDogMTUgRGVjZW1iZXIgMjAyMCAxMToyNA0KPiAN Cj4gT24gMTUvMTIvMjAyMCAwOTozNywgRGF2aWQgTGFpZ2h0IHdyb3RlOg0KPiA+IEZyb206IFBh dmVsIEJlZ3Vua292DQo+ID4+IFNlbnQ6IDE1IERlY2VtYmVyIDIwMjAgMDA6MjANCj4gPj4NCj4g Pj4gaW92X2l0ZXJfYWR2YW5jZSgpIGlzIGhlYXZpbHkgdXNlZCwgYnV0IGltcGxlbWVudGVkIHRo cm91Z2ggZ2VuZXJpYw0KPiA+PiBpdGVyYXRpb24uIEFzIGJ2ZWNzIGhhdmUgYSBzcGVjaWZpY2Fs bHkgY3JhZnRlZCBhZHZhbmNlKCkgZnVuY3Rpb24sIGkuZS4NCj4gPj4gYnZlY19pdGVyX2FkdmFu Y2UoKSwgd2hpY2ggaXMgZmFzdGVyIGFuZCBzbGltbWVyLCB1c2UgaXQgaW5zdGVhZC4NCj4gPj4N Cj4gPj4gIGxpYi9pb3ZfaXRlci5jIHwgMTkgKysrKysrKysrKysrKysrKysrKw0KPiBbLi4uXQ0K PiA+PiAgdm9pZCBpb3ZfaXRlcl9hZHZhbmNlKHN0cnVjdCBpb3ZfaXRlciAqaSwgc2l6ZV90IHNp emUpDQo+ID4+ICB7DQo+ID4+ICAJaWYgKHVubGlrZWx5KGlvdl9pdGVyX2lzX3BpcGUoaSkpKSB7 DQo+ID4+IEBAIC0xMDc3LDYgKzEwOTIsMTAgQEAgdm9pZCBpb3ZfaXRlcl9hZHZhbmNlKHN0cnVj dCBpb3ZfaXRlciAqaSwgc2l6ZV90IHNpemUpDQo+ID4+ICAJCWktPmNvdW50IC09IHNpemU7DQo+ ID4+ICAJCXJldHVybjsNCj4gPj4gIAl9DQo+ID4+ICsJaWYgKGlvdl9pdGVyX2lzX2J2ZWMoaSkp IHsNCj4gPj4gKwkJaW92X2l0ZXJfYnZlY19hZHZhbmNlKGksIHNpemUpOw0KPiA+PiArCQlyZXR1 cm47DQo+ID4+ICsJfQ0KPiA+PiAgCWl0ZXJhdGVfYW5kX2FkdmFuY2UoaSwgc2l6ZSwgdiwgMCwg MCwgMCkNCj4gPj4gIH0NCj4gPg0KPiA+IFRoaXMgc2VlbXMgdG8gYWRkIHlldCBhbm90aGVyIGNv bXBhcmlzb24gYmVmb3JlIHdoYXQgaXMgcHJvYmFibHkNCj4gPiB0aGUgY29tbW9uIGNhc2Ugb24g YW4gSU9WRUMgKGllIG5vcm1hbCB1c2Vyc3BhY2UgYnVmZmVyKS4NCj4gDQo+IElmIEFsIGZpbmFs bHkgdGFrZXMgdGhlIHBhdGNoIGZvciBpb3ZfaXRlcl9pc18qKCkgaGVscGVycyBpdCB3b3VsZA0K PiBiZSBjb21wbGV0ZWx5IG9wdGltaXNlZCBvdXQuDQoNCkkga25ldyBJIGRpZG4ndCBoYXZlIHRo YXQgcGF0aCAtIHRoZSBzb3VyY2VzIEkgbG9va2VkIGF0IGFyZW4ndCB0aGF0IG5ldy4NCkRpZG4n dCBrbm93IGl0cyBzdGF0ZS4NCg0KSW4gYW55IGNhc2UgdGhhdCBqdXN0IHN0b3BzIHRoZSBzYW1l IHRlc3QgYmVpbmcgZG9uZSB0d2ljZS4NCkluIHN0aWxsIGNoYW5nZXMgdGhlIG9yZGVyIG9mIHRo ZSB0ZXN0cy4NCg0KVGhlIHRocmVlICd1bmxpa2VseScgY2FzZXMgc2hvdWxkIHJlYWxseSBiZSBp bnNpZGUgYSBzaW5nbGUNCid1bmxpa2VseScgdGVzdCBmb3IgYWxsIHRocmVlIGJpdHMuDQpUaGVu IHRoZXJlIGlzIG9ubHkgb25lIG1pcy1wcmVkaWN0YWJsZSBqdW1wIHByaW9yIHRvIHRoZSB1c3Vh bCBwYXRoLg0KDQpCeSBhZGRpbmcgdGhlIHRlc3QgYmVmb3JlIGl0ZXJhdGVfYW5kX2FkdmFuY2Uo KSB5b3UgYXJlIChlZmZlY3RpdmVseSkNCm9wdGltaXNpbmcgZm9yIHRoZSBidmVjIChhbmQgZGlz Y2FyZCkgY2FzZXMuDQpBZGRpbmcgJ3VubGlrZWx5KCknIHdvbid0IG1ha2UgYW55IGRpZmZlcmVu Y2Ugb24gc29tZSBhcmNoaXRlY3R1cmVzLg0KSUlSQyByZWNlbnQgaW50ZWwgeDg2IGRvbid0IGhh dmUgYSAnc3RhdGljIHByZWRpY3Rpb24nIGZvciB1bmtub3duDQpicmFuY2hlcyAtIHRoZXkganVz dCB1c2Ugd2hhdGV2ZXIgaW4gaXMgdGhlIGJyYW5jaCBwcmVkaWN0b3IgdGFibGVzLg0KDQoJRGF2 aWQNCg0KLQ0KUmVnaXN0ZXJlZCBBZGRyZXNzIExha2VzaWRlLCBCcmFtbGV5IFJvYWQsIE1vdW50 IEZhcm0sIE1pbHRvbiBLZXluZXMsIE1LMSAxUFQsIFVLDQpSZWdpc3RyYXRpb24gTm86IDEzOTcz ODYgKFdhbGVzKQ0K