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[23.128.96.18]) by mx.google.com with ESMTP id f15si1607837ejr.2.2020.11.20.05.12.53; Fri, 20 Nov 2020 05:13:18 -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 S1726123AbgKTNLR (ORCPT + 99 others); Fri, 20 Nov 2020 08:11:17 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:52168 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725801AbgKTNLQ (ORCPT ); Fri, 20 Nov 2020 08:11:16 -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-288-Y6MrcUSgPimyebEP3mYpQw-1; Fri, 20 Nov 2020 13:11:12 +0000 X-MC-Unique: Y6MrcUSgPimyebEP3mYpQw-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; Fri, 20 Nov 2020 13:11:12 +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; Fri, 20 Nov 2020 13:11:12 +0000 From: David Laight To: 'Waiman Long' , Davidlohr Bueso CC: Peter Zijlstra , Ingo Molnar , Will Deacon , "linux-kernel@vger.kernel.org" , Phil Auld Subject: RE: [RFC PATCH 5/5] locking/rwsem: Remove reader optimistic spinning Thread-Topic: [RFC PATCH 5/5] locking/rwsem: Remove reader optimistic spinning Thread-Index: AQHWvqN0O6hwIV/IOUmlkB4qEdd62KnQ/N3Q Date: Fri, 20 Nov 2020 13:11:12 +0000 Message-ID: <5fe76531782f4a8492b341d5f381147b@AcuMS.aculab.com> References: <20201118030429.23017-1-longman@redhat.com> <20201118030429.23017-6-longman@redhat.com> <20201118053556.3fmmtat7upv6dtvd@linux-p48b.lan> 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 RnJvbTogV2FpbWFuIExvbmcNCj4gU2VudDogMTkgTm92ZW1iZXIgMjAyMCAxODo0MA0KLi4uDQo+ IE15IG93biB0ZXN0aW5nIGFsc28gc2hvdyBub3QgdG9vIG11Y2ggcGVyZm9ybWFuY2UgZGlmZmVy ZW5jZSB3aGVuDQo+IHJlbW92aW5nIHJlYWRlciBzcGlubmluZyBleGNlcHQgaW4gdGhlIGxpZ2h0 bHkgbG9hZGVkIGNhc2VzLg0KDQpJJ20gY29uZnVzZWQuDQoNCkkgZ290IG1hc3NpdmUgcGVyZm9y bWFuY2UgaW1wcm92ZW1lbnRzIGZyb20gY2hhbmdpbmcgYSBkcml2ZXINCndlIGhhdmUgdG8gdXNl IG11dGV4IGluc3RlYWQgb2YgdGhlIG9sZCBzZW1hcGhvcmVzICh0aGUgZHJpdmVyDQp3YXMgd3Jp dHRlbiBhIGxvbmcgdGltZSBhZ28pLg0KDQpXaGlsZSB0aGVzZSB3ZXJlbid0ICdydycgdGhlIHNh bWUgaXNzdWUgd2lsbCBhcHBseS4NCg0KVGhlIHByb2JsZW0gd2FzIHRoYXQgdGhlIHNlbWFwaG9y ZS9tdXRleCB3YXMgdHlwaWNhbGx5IG9ubHkgaGVsZCBvdmVyDQphIGZldyBpbnN0cnVjdGlvbnMg KGVnIHRvIGFkZCBhbiBpdGVtIHRvIGEgbGlzdCkuDQpCdXQgd2l0aCBzZW1hcGhvcmUgaWYgeW91 IGdvdCBjb250ZW50aW9uIHRoZSBwcm9jZXNzIGFsd2F5cyBzbGVwdC4NCk9UT0ggbXV0ZXggc3Bp biAnZm9yIGEgd2hpbGUnIGJlZm9yZSBzbGVlcGluZyBzbyB0aGUgY29kZSByYXJlbHkgc2xlcHQu DQoNClNvIEkgcmVhbGx5IGV4cGVjdCB0aGF0IHJlYWRlcnMgbmVlZCB0byBzcGluIChmb3IgYSB3 aGlsZSkgaWYNCmEgcndzZW0gKGV0YykgaXMgbG9ja2VkIGZvciB3cml0aW5nLg0KDQpDbGVhcmx5 IHlvdSByZWFsbHkgbmVlZCBhIENCVSAoQ3J5c3RhbCBCYWxsIFVuaXQpIHRvIHdvcmsgb3V0DQp3 aGV0aGVyIHRvIHNwaW4gb3Igbm90Lg0KDQoJRGF2aWQNCg0KLQ0KUmVnaXN0ZXJlZCBBZGRyZXNz IExha2VzaWRlLCBCcmFtbGV5IFJvYWQsIE1vdW50IEZhcm0sIE1pbHRvbiBLZXluZXMsIE1LMSAx UFQsIFVLDQpSZWdpc3RyYXRpb24gTm86IDEzOTczODYgKFdhbGVzKQ0K