From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752708AbbKKRf4 (ORCPT ); Wed, 11 Nov 2015 12:35:56 -0500 Received: from shards.monkeyblade.net ([149.20.54.216]:49278 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751881AbbKKRfx (ORCPT ); Wed, 11 Nov 2015 12:35:53 -0500 Date: Wed, 11 Nov 2015 12:35:48 -0500 (EST) Message-Id: <20151111.123548.1039494689070388545.davem@davemloft.net> To: alexei.starovoitov@gmail.com Cc: will.deacon@arm.com, daniel@iogearbox.net, peterz@infradead.org, arnd@arndb.de, yang.shi@linaro.org, linaro-kernel@lists.linaro.org, eric.dumazet@gmail.com, zlim.lnx@gmail.com, ast@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, xi.wang@gmail.com, catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, yhs@plumgrid.com, bblanco@plumgrid.com Subject: Re: [PATCH 2/2] arm64: bpf: add BPF XADD instruction From: David Miller In-Reply-To: <20151111172659.GA86334@ast-mbp.thefacebook.com> References: <56436420.9090401@iogearbox.net> <20151111162341.GN9562@arm.com> <20151111172659.GA86334@ast-mbp.thefacebook.com> X-Mailer: Mew version 6.6 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Wed, 11 Nov 2015 09:35:53 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexei Starovoitov Date: Wed, 11 Nov 2015 09:27:00 -0800 > BPF_XADD == atomic_add() in kernel. period. > we are not going to deprecate it or introduce something else. Agreed, it makes no sense to try and tie C99 or whatever atomic semantics to something that is already clearly defined to have exactly kernel atomic_add() semantics.