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 X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76499C433E2 for ; Mon, 14 Sep 2020 08:46:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 320ED221EB for ; Mon, 14 Sep 2020 08:46:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726135AbgINIqa (ORCPT ); Mon, 14 Sep 2020 04:46:30 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:2811 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726078AbgINIq2 (ORCPT ); Mon, 14 Sep 2020 04:46:28 -0400 Received: from lhreml724-chm.china.huawei.com (unknown [172.18.7.106]) by Forcepoint Email with ESMTP id E1553BC8B82C58024CAD; Mon, 14 Sep 2020 09:46:26 +0100 (IST) Received: from [127.0.0.1] (10.47.10.249) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Mon, 14 Sep 2020 09:46:26 +0100 Subject: Re: [PATCH 2/2] iommu/iova: Free global iova rcache on iova alloc failure To: Vijayanand Jitta , Joerg Roedel CC: , , , , Robin Murphy References: <1593785835-27250-1-git-send-email-vjitta@codeaurora.org> <1593785835-27250-2-git-send-email-vjitta@codeaurora.org> <29f44540-44f8-570d-886f-2090596a3b8e@codeaurora.org> <20200812151608.GG3721@8bytes.org> From: John Garry Message-ID: <8f3cbf23-eedc-d734-e4b3-41e8baabca15@huawei.com> Date: Mon, 14 Sep 2020 09:43:43 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.10.249] X-ClientProxiedBy: lhreml743-chm.china.huawei.com (10.201.108.193) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13/08/2020 06:36, Vijayanand Jitta wrote: > > > On 8/12/2020 8:46 PM, Joerg Roedel wrote: >> On Mon, Aug 03, 2020 at 03:30:48PM +0530, Vijayanand Jitta wrote: >>> ping? >> >> Please repost when v5.9-rc1 is released and add >> >> Robin Murphy >> >> on your Cc list. >> >> Thanks, >> >> Joerg >> > > Sure, will do. > > Thanks, > Vijay > And a cover letter would be useful also, to at least us know what changes have been made per version. > > diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c > index 4e77116..5836c87 100644 > --- a/drivers/iommu/iova.c > +++ b/drivers/iommu/iova.c > @@ -442,6 +442,7 @@ struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn) > flush_rcache = false; > for_each_online_cpu(cpu) > free_cpu_cached_iovas(cpu, iovad); > + free_global_cached_iovas(iovad); Have you seen an issue where this is needed? If we have filled the IOVA space, then as a measure we flush all the CPU rcaches, and then there should be free IOVA space and we can make progress. And it may be useful to still have the global depots to use straightaway then to swap into empty CPU rcaches. > goto retry; > } > > @@ -1055,5 +1056,27 @@ void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad) > } > } > > +/* > + * free all the IOVA ranges of global cache > + */ > +void free_global_cached_iovas(struct iova_domain *iovad) > +{ > + struct iova_rcache *rcache; > + unsigned long flags; > + int i, j; > + > + for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { > + rcache = &iovad->rcaches[i]; > + spin_lock_irqsave(&rcache->lock, flags); > + for (j = 0; j < rcache->depot_size; ++j) { > + iova_magazine_free_pfns(rcache->depot[j], iovad); > + iova_magazine_free(rcache->depot[j]); > + rcache->depot[j] = NULL; > + } > + rcache->depot_size = 0; > + spin_unlock_irqrestore(&rcache->lock, flags); > + } > +} > + > MODULE_AUTHOR("Anil S Keshavamurthy "); > MODULE_LICENSE("GPL"); > diff --git a/include/linux/iova.h b/include/linux/iova.h > index a0637ab..a905726 100644 > --- a/include/linux/iova.h > +++ b/include/linux/iova.h why is this in the iova.h, when it is only used internally in iova.c? > @@ -163,6 +163,7 @@ int init_iova_flush_queue(struct iova_domain *iovad, > struct iova *split_and_remove_iova(struct iova_domain *iovad, > struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi); > void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad); > +void free_global_cached_iovas(struct iova_domain *iovad); > #else > static inline int iova_cache_get(void) > { > @@ -270,6 +271,11 @@ static inline void free_cpu_cached_iovas(unsigned int cpu, > struct iova_domain *iovad) > { > } > + > +static inline void free_global_cached_iovas(struct iova_domain *iovad) > +{ > +} > + > #endif > > #endif