From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42644) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bzmKs-0004kt-2A for qemu-devel@nongnu.org; Thu, 27 Oct 2016 11:11:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bzmKo-0007jr-G5 for qemu-devel@nongnu.org; Thu, 27 Oct 2016 11:11:18 -0400 Received: from mail-wm0-x22d.google.com ([2a00:1450:400c:c09::22d]:35296) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1bzmKo-0007iz-9F for qemu-devel@nongnu.org; Thu, 27 Oct 2016 11:11:14 -0400 Received: by mail-wm0-x22d.google.com with SMTP id e69so40999673wmg.0 for ; Thu, 27 Oct 2016 08:11:14 -0700 (PDT) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Thu, 27 Oct 2016 16:10:19 +0100 Message-Id: <20161027151030.20863-23-alex.bennee@linaro.org> In-Reply-To: <20161027151030.20863-1-alex.bennee@linaro.org> References: <20161027151030.20863-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v5 22/33] atomic: introduce cmpxchg_bool List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: pbonzini@redhat.com Cc: qemu-devel@nongnu.org, mttcg@listserver.greensocs.com, fred.konrad@greensocs.com, a.rigo@virtualopensystems.com, cota@braap.org, bobby.prani@gmail.com, nikunj@linux.vnet.ibm.com, mark.burton@greensocs.com, jan.kiszka@siemens.com, serge.fdrv@gmail.com, rth@twiddle.net, peter.maydell@linaro.org, claudio.fontana@huawei.com, =?UTF-8?q?Alex=20Benn=C3=A9e?= This allows for slightly neater code when checking for success of a cmpxchg operation. Signed-off-by: Alex Bennée --- v4 (base-patches) - brought forward from ARM enabling patches - remove the un-needed extra temps --- include/qemu/atomic.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/qemu/atomic.h b/include/qemu/atomic.h index 49cf55f..bd74b75 100644 --- a/include/qemu/atomic.h +++ b/include/qemu/atomic.h @@ -205,6 +205,14 @@ atomic_cmpxchg__nocheck(ptr, old, new); \ }) +#define atomic_bool_cmpxchg(ptr, old, new) \ + ({ \ + typeof(*ptr) _old = (old), _new = (new); \ + __atomic_compare_exchange(ptr, &_old, &_new, false, \ + __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); \ + }) + + /* Provide shorter names for GCC atomic builtins, return old value */ #define atomic_fetch_inc(ptr) __atomic_fetch_add(ptr, 1, __ATOMIC_SEQ_CST) #define atomic_fetch_dec(ptr) __atomic_fetch_sub(ptr, 1, __ATOMIC_SEQ_CST) @@ -432,6 +440,7 @@ #define atomic_cmpxchg(ptr, old, new) __sync_val_compare_and_swap(ptr, old, new) #define atomic_cmpxchg__nocheck(ptr, old, new) atomic_cmpxchg(ptr, old, new) +#define atomic_bool_cmpxchg(ptr, old, new) __sync_bool_compare_and_swap(ptr, old, new) /* And even shorter names that return void. */ #define atomic_inc(ptr) ((void) __sync_fetch_and_add(ptr, 1)) -- 2.10.1