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 D45B4C25B08 for ; Wed, 17 Aug 2022 10:36:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238502AbiHQKge (ORCPT ); Wed, 17 Aug 2022 06:36:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41742 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232195AbiHQKgb (ORCPT ); Wed, 17 Aug 2022 06:36:31 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 727FC51A33 for ; Wed, 17 Aug 2022 03:36:30 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 06EF7113E; Wed, 17 Aug 2022 03:36:31 -0700 (PDT) Received: from [10.57.13.141] (unknown [10.57.13.141]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 530193F67D; Wed, 17 Aug 2022 03:36:29 -0700 (PDT) Message-ID: <388efa0d-d8b8-a837-b301-ef04ba3d6e4e@arm.com> Date: Wed, 17 Aug 2022 11:36:25 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Subject: Re: [PATCH 1/3] iova: Remove some magazine pointer NULL checks Content-Language: en-GB To: John Garry , joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org References: <1660730984-30333-1-git-send-email-john.garry@huawei.com> <1660730984-30333-2-git-send-email-john.garry@huawei.com> From: Robin Murphy In-Reply-To: <1660730984-30333-2-git-send-email-john.garry@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-08-17 11:09, John Garry wrote: > Since commit 32e92d9f6f87 ("iommu/iova: Separate out rcache init") it > has not been possible to have NULL CPU rcache "loaded" or "prev" magazine > pointers. As such, the checks in iova_magazine_full(), > iova_magazine_empty(), and iova_magazine_free_pfns() may be dropped. Reviewed-by: Robin Murphy > Signed-off-by: John Garry > --- > drivers/iommu/iova.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c > index 47d1983dfa2a..580fdf669922 100644 > --- a/drivers/iommu/iova.c > +++ b/drivers/iommu/iova.c > @@ -661,9 +661,6 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad) > unsigned long flags; > int i; > > - if (!mag) > - return; > - > spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); > > for (i = 0 ; i < mag->size; ++i) { > @@ -683,12 +680,12 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad) > > static bool iova_magazine_full(struct iova_magazine *mag) > { > - return (mag && mag->size == IOVA_MAG_SIZE); > + return mag->size == IOVA_MAG_SIZE; > } > > static bool iova_magazine_empty(struct iova_magazine *mag) > { > - return (!mag || mag->size == 0); > + return mag->size == 0; > } > > static unsigned long iova_magazine_pop(struct iova_magazine *mag,