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 58C80ECAAA1 for ; Mon, 12 Sep 2022 04:57:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229520AbiILE5E (ORCPT ); Mon, 12 Sep 2022 00:57:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229636AbiILE4r (ORCPT ); Mon, 12 Sep 2022 00:56:47 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D47327FE2 for ; Sun, 11 Sep 2022 21:56:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F369260AF4 for ; Mon, 12 Sep 2022 04:56:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58A3FC433C1; Mon, 12 Sep 2022 04:56:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1662958596; bh=DTFRenkSK/6d0vSvDnajzMqoEhjS4nZaRgV/lbPIZsc=; h=Date:To:From:Subject:From; b=MlrtuPXz8T+WtyqMX1LKutV0tN0+OxrR+Bu2GgA4b4GAjcbQB4v8Yqxejz50WCxi/ uw2qRtADTtKcxPW5khJXZGi17AQfFnim2euFLdYYdKS9c5jopL32N2AWMr3WJ/MCnD iuYoEmP0vmX/EbUAdqYOukL4cD9/xoi/ImjMAxAs= Date: Sun, 11 Sep 2022 21:56:35 -0700 To: mm-commits@vger.kernel.org, viro@zeniv.linux.org.uk, bcrl@kvack.org, ubizjak@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-nonmm-stable] aio-use-atomic_try_cmpxchg-in-__get_reqs_available.patch removed from -mm tree Message-Id: <20220912045636.58A3FC433C1@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: aio: use atomic_try_cmpxchg in __get_reqs_available has been removed from the -mm tree. Its filename was aio-use-atomic_try_cmpxchg-in-__get_reqs_available.patch This patch was dropped because it was merged into the mm-nonmm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Uros Bizjak Subject: aio: use atomic_try_cmpxchg in __get_reqs_available Date: Thu, 14 Jul 2022 18:48:51 +0200 Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old in __get_reqs_available. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails, enabling further code simplifications. No functional change intended. Link: https://lkml.kernel.org/r/20220714164851.3055-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak Cc: Benjamin LaHaise Cc: Alexander Viro Signed-off-by: Andrew Morton --- fs/aio.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) --- a/fs/aio.c~aio-use-atomic_try_cmpxchg-in-__get_reqs_available +++ a/fs/aio.c @@ -951,16 +951,13 @@ static bool __get_reqs_available(struct local_irq_save(flags); kcpu = this_cpu_ptr(ctx->cpu); if (!kcpu->reqs_available) { - int old, avail = atomic_read(&ctx->reqs_available); + int avail = atomic_read(&ctx->reqs_available); do { if (avail < ctx->req_batch) goto out; - - old = avail; - avail = atomic_cmpxchg(&ctx->reqs_available, - avail, avail - ctx->req_batch); - } while (avail != old); + } while (!atomic_try_cmpxchg(&ctx->reqs_available, + &avail, avail - ctx->req_batch)); kcpu->reqs_available += ctx->req_batch; } _ Patches currently in -mm which might be from ubizjak@gmail.com are