Received: by 2002:a05:6a10:6744:0:0:0:0 with SMTP id w4csp597076pxu; Thu, 15 Oct 2020 11:29:39 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxijBdaA/RKvers9ty/atKLqDczjJ2F3+WLmoaeCWTSSEn3WhU7VuoH5IrGlBRQjkPXeBMx X-Received: by 2002:a17:906:3b91:: with SMTP id u17mr5759703ejf.504.1602786579736; Thu, 15 Oct 2020 11:29:39 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1602786579; cv=none; d=google.com; s=arc-20160816; b=DjNZzRKohOqGWoQh4cLJIWoSSkLA/BM6mSOCcYcE/IK5kh0O+ZowXdRlC+nXCjGiZo mgjVnKwL+Gsz9nYzo66O5tK2s6138jGjkoDsbdMTpSOo3+Djq2CjkiE86BFjx+rtgQTH K4EkvO0tS6JVD05MExtGEj/YTOaGarVBA8tzxv2wvXOI2AyfTyRVVWI7cJ+r5mbw+NQO RZK7fNJNLz7UIcHEwXjnXfPElakoX2PREyOIayh1Al7KukKfO4+piQWo86XZQyJ1aLhq yIwlBvYwKqzocgKgmbI9jHZhGSjqeX8aPIojHysljHR88egU9A9X3I4/OU6mwjXlSW+R zVCg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:content-language :mime-version:accept-language:in-reply-to:references:message-id:date :thread-index:thread-topic:subject:cc:to:from; bh=QrQg9Bksp/1jHCLztUuS40d2hgn1n0L+/s9fyWjICeM=; b=WBG0fjCQTlUWNkE7wmIyxGsrBf9DyX42VdJXUuLmqdZLJJ1DNsgQ2AXe7Zye6tCSAc mlT25ZFwkw9DhdEiEaCq8x1+abrTuomxKcFcjpgwea0QqMjKlhTgySIdCylCDThgQmPx NV7V5rTWX4OcxmPkKatgAlF/p5BtBjPd69lxBAC384YfAQcswDV+ivieAWw44IU5xg9N BVuPw9xOAk5wfnIkFFPj1WfuZET7V2/E896yqJLF7qS2LWuonZZ2y4Xv8mFZ8+xkZvHg mDh3x/EzVBieQUUDAuL8c2Z2d2JfeA4qP9Qp1yeMd0xQjsKXp7priEgnTTMyZEj+uhVr 95fw== ARC-Authentication-Results: i=1; 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id a3si3091761ejd.238.2020.10.15.11.29.08; Thu, 15 Oct 2020 11:29:39 -0700 (PDT) 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 S2389680AbgJOPYR (ORCPT + 99 others); Thu, 15 Oct 2020 11:24:17 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:28555 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388357AbgJOPYR (ORCPT ); Thu, 15 Oct 2020 11:24:17 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-193-gJBnQdcfNGGK9k5C1zNBcw-1; Thu, 15 Oct 2020 16:24:10 +0100 X-MC-Unique: gJBnQdcfNGGK9k5C1zNBcw-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; Thu, 15 Oct 2020 16:24:09 +0100 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; Thu, 15 Oct 2020 16:24:09 +0100 From: David Laight To: 'Arvind Sankar' CC: Nathan Chancellor , Nick Desaulniers , "clang-built-linux@googlegroups.com" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH] compiler.h: Fix barrier_data() on clang Thread-Topic: [PATCH] compiler.h: Fix barrier_data() on clang Thread-Index: AQHWonC0tkOz0iWHskSkJuRX+uCeV6mYVxvwgABW1oCAABhpoA== Date: Thu, 15 Oct 2020 15:24:09 +0000 Message-ID: <4a8c47b5eeb44b789abbb617f0a95993@AcuMS.aculab.com> References: <20201014212631.207844-1-nivedita@alum.mit.edu> <1653ace9164c4a3a8be50b3d2c9ff816@AcuMS.aculab.com> <20201015144515.GA572410@rani.riverdale.lan> In-Reply-To: <20201015144515.GA572410@rani.riverdale.lan> 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 RnJvbTogQXJ2aW5kIFNhbmthcg0KPiBTZW50OiAxNSBPY3RvYmVyIDIwMjAgMTU6NDUNCj4gDQo+ IE9uIFRodSwgT2N0IDE1LCAyMDIwIGF0IDA4OjUwOjA1QU0gKzAwMDAsIERhdmlkIExhaWdodCB3 cm90ZToNCj4gPiBGcm9tOiBBcnZpbmQgU2Fua2FyDQo+ID4gPiBTZW50OiAxNCBPY3RvYmVyIDIw MjAgMjI6MjcNCj4gPiAuLi4NCj4gPiA+ICsvKg0KPiA+ID4gKyAqIFRoaXMgdmVyc2lvbiBpcyBp LmUuIHRvIHByZXZlbnQgZGVhZCBzdG9yZXMgZWxpbWluYXRpb24gb24gQHB0cg0KPiA+ID4gKyAq IHdoZXJlIGdjYyBhbmQgbGx2bSBtYXkgYmVoYXZlIGRpZmZlcmVudGx5IHdoZW4gb3RoZXJ3aXNl IHVzaW5nDQo+ID4gPiArICogbm9ybWFsIGJhcnJpZXIoKTogd2hpbGUgZ2NjIGJlaGF2aW9yIGdl dHMgYWxvbmcgd2l0aCBhIG5vcm1hbA0KPiA+ID4gKyAqIGJhcnJpZXIoKSwgbGx2bSBuZWVkcyBh biBleHBsaWNpdCBpbnB1dCB2YXJpYWJsZSB0byBiZSBhc3N1bWVkDQo+ID4gPiArICogY2xvYmJl cmVkLiBUaGUgaXNzdWUgaXMgYXMgZm9sbG93czogd2hpbGUgdGhlIGlubGluZSBhc20gbWlnaHQN Cj4gPiA+ICsgKiBhY2Nlc3MgYW55IG1lbW9yeSBpdCB3YW50cywgdGhlIGNvbXBpbGVyIGNvdWxk IGhhdmUgZml0IGFsbCBvZg0KPiA+ID4gKyAqIEBwdHIgaW50byBtZW1vcnkgcmVnaXN0ZXJzIGlu c3RlYWQsIGFuZCBzaW5jZSBAcHRyIG5ldmVyIGVzY2FwZWQNCj4gPiA+ICsgKiBmcm9tIHRoYXQs IGl0IHByb3ZlZCB0aGF0IHRoZSBpbmxpbmUgYXNtIHdhc24ndCB0b3VjaGluZyBhbnkgb2YNCj4g PiA+ICsgKiBpdC4gVGhpcyB2ZXJzaW9uIHdvcmtzIHdlbGwgd2l0aCBib3RoIGNvbXBpbGVycywg aS5lLiB3ZSdyZSB0ZWxsaW5nDQo+ID4gPiArICogdGhlIGNvbXBpbGVyIHRoYXQgdGhlIGlubGlu ZSBhc20gYWJzb2x1dGVseSBtYXkgc2VlIHRoZSBjb250ZW50cw0KPiA+ID4gKyAqIG9mIEBwdHIu IFNlZSBhbHNvOiBodHRwczovL2xsdm0ub3JnL2J1Z3Mvc2hvd19idWcuY2dpP2lkPTE1NDk1DQo+ ID4gPiArICovDQo+ID4gPiArIyBkZWZpbmUgYmFycmllcl9kYXRhKHB0cikgX19hc21fXyBfX3Zv bGF0aWxlX18oIiI6IDoiciIocHRyKSA6Im1lbW9yeSIpDQo+ID4NCj4gPiBUaGF0IGNvbW1lbnQg ZG9lc24ndCBhY3R1YWxseSBtYXRjaCB0aGUgYXNtIHN0YXRlbWVudC4NCj4gPiBBbHRob3VnaCB0 aGUgYXNtIHN0YXRlbWVudCBwcm9iYWJseSBoYXMgdGhlIGRlc2lyZWQgZWZmZWN0Lg0KPiA+DQo+ ID4gVGhlICJyIihwdHIpIGNvbnN0cmFpbnQgb25seSBwYXNzZXMgdGhlIGFkZHJlc3Mgb2YgdGhl IGJ1ZmZlcg0KPiA+IGludG8gdGhlIGFzbSAtIGl0IGRvZXNuJ3Qgc2F5IGFueXRoaW5nIGF0IGFs bCBhYm91dCB0aGUgYXNzb2NpYXRlZA0KPiA+IG1lbW9yeS4NCj4gPg0KPiA+IFdoYXQgdGhlICJy IihwdHIpIGFjdHVhbGx5IGRvZXMgaXMgdG8gZm9yY2UgdGhlIGFkZHJlc3Mgb2YgdGhlDQo+ID4g YXNzb2NpYXRlZCBkYXRhIHRvIGJlIHRha2VuLg0KPiA+IFRoaXMgbWVhbnMgdGhhdCBvbi1zdGFj ayBzcGFjZSBtdXN0IGFjdHVhbGx5IGJlIGFsbG9jYXRlZC4NCj4gPiBUaGUgIm1lbW9yeSIgY2xv YmJlciB3aWxsIHRoZW4gZm9yY2UgdGhlIHJlZ2lzdGVycyBjYWNoaW5nDQo+ID4gdGhlIHZhcmlh YmxlIGJlIHdyaXR0ZW4gb3V0IHRvIHN0YWNrLg0KPiA+DQo+IA0KPiBJIHRoaW5rIHRoZSBjb21t ZW50IGlzIHVuY2xlYXIgbm93IHRoYXQgeW91IGJyaW5nIGl0IHVwLCBidXQgdGhlIHByb2JsZW0N Cj4gaXQgYWN0dWFsbHkgYWRkcmVzc2VzIGlzIG5vdCB0aGF0IHRoZSBkYXRhIGlzIGhlbGQgaW4g cmVnaXN0ZXJzOiBpbiB0aGUNCj4gc2hhMjU2X3RyYW5zZm9ybSgpIGNhc2UgbWVudGlvbmVkIGlu IHRoZSBjb21taXQgbWVzc2FnZSwgZm9yIGV4YW1wbGUsDQo+IHRoZSBkYXRhIGlzIGluIGZhY3Qg aW4gbWVtb3J5IGV2ZW4gYmVmb3JlIHRoaXMgY2hhbmdlIChpdCdzIGEgMjU2LWJ5dGUNCj4gYXJy YXkpLCBhbmQgdGhhdCB0b2dldGhlciB3aXRoIHRoZSBtZW1vcnkgY2xvYmJlciBpcyBlbm91Z2gg Zm9yIGdjYyB0bw0KPiBhc3N1bWUgdGhhdCB0aGUgYXNtIG1pZ2h0IHVzZSBpdC4gQnV0IHdpdGgg Y2xhbmcsIGlmIHRoZSBhZGRyZXNzIG9mIHRoYXQNCj4gZGF0YSBoYXMgbmV2ZXIgZXNjYXBlZCAt LSBpbiB0aGlzIGNhc2UgdGhlIGRhdGEgaXMgYSBsb2NhbCB2YXJpYWJsZQ0KPiB3aG9zZSBhZGRy ZXNzIHdhcyBuZXZlciBwYXNzZWQgb3V0IG9mIHRoZSBmdW5jdGlvbiAtLSB0aGUgY29tcGlsZXIN Cj4gYXNzdW1lcyB0aGF0IHRoZSBhc20gY2Fubm90IHBvc3NpYmx5IGRlcGVuZCBvbiB0aGF0IG1l bW9yeSwgYmVjYXVzZSBpdA0KPiBoYXMgbm8gd2F5IG9mIGdldHRpbmcgaXRzIGFkZHJlc3MuDQoN Ck9rLCBzbGlnaHRseSBkaWZmZXJlbnQgZnJvbSB3aGF0IGkgdGhvdWdodC4NCkJ1dCB0aGUgY3Vy cmVudCBjb21tZW50IGlzIGp1c3Qgd3JvbmcuDQoNCj4gUGFzc2luZyBwdHIgdG8gdGhlIGlubGlu ZSBhc20gdGVsbHMgY2xhbmcgdGhhdCB0aGUgYXNtIGtub3dzIHRoZQ0KPiBhZGRyZXNzLCBhbmQg c2luY2UgaXQgYWxzbyBoYXMgYSBtZW1vcnkgY2xvYmJlciwgdGhhdCBpdCBtYXkgdXNlIHRoZQ0K PiBkYXRhLiBUaGlzIGlzIHNvbWV3aGF0IHN1Ym9wdGltYWwsIHNpbmNlIGlmIHRoZSBkYXRhIHdh cyBzb21lIHNtYWxsDQo+IHN0cnVjdHVyZSB0aGF0IHRoZSBjb21waWxlciB3YXMganVzdCBob2xk aW5nIGluIHJlZ2lzdGVycyBvcmlnaW5hbGx5LA0KPiBmb3JjaW5nIGl0IG91dCB0byBtZW1vcnkg aXMgYSBiYWQgdGhpbmcgdG8gZG8uDQo+IA0KPiA+IElmIHlvdSBvbmx5IHdhbnQgdG8gZm9yY2Ug c3RvcmVzIG9uIGEgc2luZ2xlIGRhdGEgc3RydWN0dXJlDQo+ID4geW91IGFjdHVhbGx5IHdhbnQ6 DQo+ID4gI2RlZmluZSBiYXJyaWVyX2RhdGEocHRyKSBhc20gdm9sYXRpbGUoIiIgOjogIm0iKCpw dHIpKQ0KPiA+IGFsdGhvdWdoIGl0IHdvdWxkIGJlIGJlc3QgdGhlbiB0byBhZGQgYW4gZXhwbGlj aXQgc2l6ZQ0KPiA+IGFuZCBhc3NvY2lhdGVkIGNhc3QuDQo+ID4NCj4gDQo+IGkuZS4gc29tZXRo aW5nIGxpa2U6DQo+IAlzdGF0aWMgaW5saW5lIHZvaWQgYmFycmllcl9kYXRhKHZvaWQgKnB0ciwg c2l6ZV90IHNpemUpDQo+IAl7DQo+IAkJYXNtIHZvbGF0aWxlKCIiIDogIittIigqKGNoYXIgKCop W3NpemVdKXB0cikpOw0KDQpJIHRoaW5rIGl0IGhhcyB0byBiZSBhIHN0cnVjdCB3aXRoIGFuIGFy cmF5IG1lbWJlcj8NCg0KPiAJfQ0KPiBwbHVzIHNvbWUgbWFnaWMgdG8gZGlzYWJsZSB0aGUgVkxB IHdhcm5pbmcsIG90aGVyd2lzZSBpdCBjYXVzZXMgYSBidWlsZA0KPiBlcnJvci4NCg0KSXQgc2hv dWxkbid0IGlmIHRoZSBzaXplIGlzIGEgY29tcGlsZSB0aW1lIGNvbnN0YW50Lg0KQW5kIGdpdmVu IHRoaXMgaXMgYW4gaW5zdHJ1Y3Rpb24gdG8gdGhlIGNvbXBpbGVyIGl0IGJldHRlciBiZS4NCg0K PiBCdXQgSSB0aGluayB0aGF0IG1pZ2h0IGxlYWQgdG8gZXZlbiBtb3JlIHN1YnRsZSBpc3N1ZXMg YnkgZHJvcHBpbmcgdGhlDQo+IG1lbW9yeSBjbG9iYmVyLiBGb3IgZXhhbXBsZSAoYW5kIHRoaXMg aXMgYWN0dWFsbHkgZG9uZSBpbg0KPiBzaGEyNTZfdHJhbnNmb3JtKCkgYXMgd2VsbCwgdGhvdWdo IHRoZSB6ZXJvJ2luZyBzaW1wbHkgZG9lc24ndCB3b3JrIHdpdGgNCj4gYW55IGNvbXBpbGVyLCBh cyBpdCdzIG1pc3NpbmcgdGhlIGJhcnJpZXJfZGF0YSgpJ3MpOg0KPiANCj4gCXVuc2lnbmVkIGxv bmcgeCwgeTsNCj4gCS4uLiBkbyBzb21ldGhpbmcgc2VjcmV0IHdpdGggeC95IC4uLg0KPiAJeCA9 IHkgPSAwOw0KPiAJYmFycmllcl9kYXRhKCZ4LCBzaXplb2YoeCkpOw0KPiAJYmFycmllcl9kYXRh KCZ5LCBzaXplb2YoeSkpOw0KPiAJcmV0dXJuOw0KPiANCj4gU2luY2UgeCBpcyBub3QgdXNlZCBh ZnRlciBpdHMgYmFycmllcl9kYXRhKCksIEkgdGhpbmsgdGhlIGNvbXBpbGVyIHdvdWxkDQo+IGJl IHdpdGhpbiBpdHMgcmlnaHRzIHRvIHR1cm4gdGhhdCBpbnRvOg0KPiANCj4gCXhvcmwJJWVheCwg JWVheA0KPiAJbGVhcQktMTYoJXJicCksICVyZHgJLy8gJnggPT0gLTE2KCVyYnApDQo+IAltb3Zx CSVlYXgsICglcmR4KQkvLyB4ID0gMDsNCj4gCS8vIGlubGluZSBhc20gZm9yIGJhcnJpZXJfZGF0 YSgmeCwgc2l6ZW9mKHgpKTsNCj4gCW1vdnEJJWVheCwgKCVyZHgpCS8vIHkgPSAwOyAoISkNCj4g CS8vIGlubGluZSBhc20gZm9yIGJhcnJpZXJfZGF0YSgmeSwgc2l6ZW9mKHkpKTsNCj4gDQo+IHdo aWNoIHNhdmVzIG9uZSBpbnN0cnVjdGlvbiBieSBwdXR0aW5nIHkgYXQgdGhlIHNhbWUgbG9jYXRp b24gYXMgeCwgb25jZQ0KPiB4IGlzIGRlYWQuDQo+IA0KPiBXaXRoIGEgbWVtb3J5IGNsb2JiZXIs IHRoZSBjb21waWxlciBoYXMgdG8ga2VlcCB4IGFuZCB5IGF0IGRpZmZlcmVudA0KPiBhZGRyZXNz ZXMsIHNpbmNlIHRoZSBmaXJzdCBiYXJyaWVyX2RhdGEoKSBtaWdodCBoYXZlIHNhdmVkIHRoZSBh ZGRyZXNzDQo+IG9mIHguDQoNCk1heWJlICIrbSIoKnB0cikgOiAiciIocHRyKSB3b3VsZCB3b3Jr Lg0KT1RPSCBhICJtZW1vcnkiIGNsb2JiZXIgYXQgdGhlIGJvdHRvbSBvZiBhIGZ1bmN0aW9uIGlz bid0IGdvaW5nIHRvDQpjYXVzZSBibG9hdC4NCg0KVGhlIGV4cGxpY2l0IHJhbmdlZCBtZW1vcnkg YWNjZXNzICh3aXRob3V0ICJtZW1vcnkiKSBwcm9iYWJseSBoYXMgaXRzDQp1c2VzIC0gYnV0IG9u bHkgaWYgdGhlIGZ1bGwgIm1lbW9yeSIgY2xvYmJlciBjYXVzZXMgZ3JpZWYuDQoNCglEYXZpZA0K DQotDQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFy bSwgTWlsdG9uIEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAo V2FsZXMpDQo=