Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753360Ab3GORtx (ORCPT ); Mon, 15 Jul 2013 13:49:53 -0400 Received: from mail-vc0-f173.google.com ([209.85.220.173]:54575 "EHLO mail-vc0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752087Ab3GORtw (ORCPT ); Mon, 15 Jul 2013 13:49:52 -0400 MIME-Version: 1.0 In-Reply-To: References: <1373361330-3946-1-git-send-email-realmz6@kernel.org> Date: Mon, 15 Jul 2013 10:49:51 -0700 X-Google-Sender-Auth: Rmpb-tr_pmWD_vcb_PjmiEgzWRE Message-ID: Subject: Re: [uclinux-dist-devel] [GIT PULL] Blackfin updates for 3.11 From: Linus Torvalds To: Geert Uytterhoeven Cc: Steven Miao , Stephen Rothwell , "uclinux-dist-devel@blackfin.uclinux.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 846 Lines: 21 On Mon, Jul 15, 2013 at 10:28 AM, Geert Uytterhoeven wrote: > > but the first one is non-trivial: using xchg() on atomic_t is a bit gross... It's also broken. There's no guarantee that an "atomic_t" is just a value. Now, the old sparc32 stuff (which hid lock bits in atomic_t) may be gone, but it's still the case that atomic_t may not actually work with xchg. (In *practice* it works on normal architectures, so I'm not saying that we don't have it, but it's a bug if we do). There are "atomic_xchg()" and "atomic_xchg64()" functions that are supported. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/