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 73C3BC0015E for ; Fri, 21 Jul 2023 11:51:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230268AbjGULvs (ORCPT ); Fri, 21 Jul 2023 07:51:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230224AbjGULvq (ORCPT ); Fri, 21 Jul 2023 07:51:46 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 707982D7F for ; Fri, 21 Jul 2023 04:51:43 -0700 (PDT) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with both STARTTLS and AUTH (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-148-z_DqXMMUPVCfSx5Bf5_Iew-1; Fri, 21 Jul 2023 12:51:40 +0100 X-MC-Unique: z_DqXMMUPVCfSx5Bf5_Iew-1 Received: from AcuMS.Aculab.com (10.202.163.4) by AcuMS.aculab.com (10.202.163.4) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Fri, 21 Jul 2023 12:51:39 +0100 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.048; Fri, 21 Jul 2023 12:51:39 +0100 From: David Laight To: 'Alan Huang' , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , "rcu@vger.kernel.org" CC: "Paul E. McKenney" , Eric Dumazet , "roman.gushchin@linux.dev" Subject: RE: Question about the barrier() in hlist_nulls_for_each_entry_rcu() Thread-Topic: Question about the barrier() in hlist_nulls_for_each_entry_rcu() Thread-Index: AQHZuzuWW9UBwZmf30GL9p6MGC4yBq/EGshg Date: Fri, 21 Jul 2023 11:51:39 +0000 Message-ID: References: <04C1E631-725C-47AD-9914-25D5CE04DFF4@gmail.com> In-Reply-To: <04C1E631-725C-47AD-9914-25D5CE04DFF4@gmail.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 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 RnJvbTogQWxhbiBIdWFuZw0KPiBTZW50OiAyMCBKdWx5IDIwMjMgMTk6NTQNCj4gDQo+IEkgbm90 aWNlZCBhIGNvbW1pdCBjODdhMTI0YTVkNWUo4oCcbmV0OiBmb3JjZSBhIHJlbG9hZCBvZiBmaXJz dCBpdGVtIGluIGhsaXN0X251bGxzX2Zvcl9lYWNoX2VudHJ5X3JjdeKAnSkNCj4gYW5kIGEgcmVs YXRlZCBkaXNjdXNzaW9uIFsxXS4NCg0KSG1tbS4uLiB0aGF0IHdhcyBhbGwgYWJvdXQgdGhlIHJl dHJ5IGxvb3AgaW4gaXB2NC91ZHAuYw0KDQpBRkFJQ1QgdGhhdCByZXRyeSBnb3QgZGVsZXRlZCBi eSBjYTA2NWQwYy4NCg0KVGhhdCBhbHNvIGNoYW5nZXMgdGhlIGxpc3QgZnJvbSBobGlzdF9udWxs c194eHggdG8gaGxpc3RfeHh4Lg0KKEknbSBub3Qgc3VyZSBvZiB0aGUgZGlmZmVyZW5jZSkNCg0K VGhpcyBtaWdodCBiZSB3aHkgd2UncmUgc2VlaW5nIHVuZXhwZWN0ZWQgJ3BvcnQgdW5yZWFjaGFi bGUnIG1lc3NhZ2VzPw0KDQpRdWl0ZSB3aHkgdGhhdCBoYXMganVzdCBzdGFydGVkIGhhcHBlbmlu ZyBpcyBhbm90aGVyIGlzc3VlLg0KTW9zdCBvZiB0aGUgVURQIHNvY2tldHMgd2UgY3JlYXRlIGFy ZW4ndCAnY29ubmVjdGVkJyBzbyBJIGRvbid0DQpiZWxpZXZlIHRoZXkgZ2V0IG1vdmVkIGJldHdl ZW4gaGFzaCBjaGFpbnMgLSBqdXN0IGRlbGV0ZWQuDQpUaGUgZGVsZXRpb24gc2hvdWxkIGxlYXZl IHRoZSBoYXNoIGNoYWluIGludGFjdC4NCg0KCURhdmlkDQoNCi0NClJlZ2lzdGVyZWQgQWRkcmVz cyBMYWtlc2lkZSwgQnJhbWxleSBSb2FkLCBNb3VudCBGYXJtLCBNaWx0b24gS2V5bmVzLCBNSzEg MVBULCBVSw0KUmVnaXN0cmF0aW9uIE5vOiAxMzk3Mzg2IChXYWxlcykNCg==