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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,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 33B62C4338F for ; Wed, 11 Aug 2021 10:31:57 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B715660FC3 for ; Wed, 11 Aug 2021 10:31:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org B715660FC3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 7BDAF40393; Wed, 11 Aug 2021 10:31:56 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id T-lp2exf7Fnw; Wed, 11 Aug 2021 10:31:52 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp2.osuosl.org (Postfix) with ESMTPS id 0C96740111; Wed, 11 Aug 2021 10:31:52 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id E1CD5C001A; Wed, 11 Aug 2021 10:31:51 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 12C56C000E for ; Wed, 11 Aug 2021 10:31:50 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 0FC2083216 for ; Wed, 11 Aug 2021 10:31:50 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JdX-JR0j3O4i for ; Wed, 11 Aug 2021 10:31:49 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by smtp1.osuosl.org (Postfix) with ESMTPS id 172F2831CA for ; Wed, 11 Aug 2021 10:31:48 +0000 (UTC) Received: from fraeml735-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Gl5hK69ZTz6BDkl; Wed, 11 Aug 2021 18:31:13 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml735-chm.china.huawei.com (10.206.15.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Wed, 11 Aug 2021 12:31:46 +0200 Received: from [10.47.80.4] (10.47.80.4) 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 15.1.2176.2; Wed, 11 Aug 2021 11:31:45 +0100 Subject: Re: [PATCH RFC 2/8] iommu/arm-smmu-v3: Add and use static helper function arm_smmu_cmdq_issue_cmd_with_sync() To: Will Deacon , "Leizhen (ThunderTown)" References: <20210626110130.2416-1-thunder.leizhen@huawei.com> <20210626110130.2416-3-thunder.leizhen@huawei.com> <20210810182454.GB3296@willie-the-truck> <20210811100905.GB4426@willie-the-truck> From: John Garry Message-ID: Date: Wed, 11 Aug 2021 11:31:08 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 MIME-Version: 1.0 In-Reply-To: <20210811100905.GB4426@willie-the-truck> Content-Language: en-US X-Originating-IP: [10.47.80.4] X-ClientProxiedBy: lhreml712-chm.china.huawei.com (10.201.108.63) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Cc: iommu , Robin Murphy , linux-kernel , linux-arm-kernel X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" >>>> Obviously, inserting as many commands at a time as possible can reduce the >>>> number of times the mutex contention participates, thereby improving the >>>> overall performance. At least it reduces the number of calls to function >>>> arm_smmu_cmdq_issue_cmdlist(). >>>> >>>> Therefore, function arm_smmu_cmdq_issue_cmd_with_sync() is added to insert >>>> the 'cmd+sync' commands at a time. >>>> >>>> Signed-off-by: Zhen Lei >>>> --- >>>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 33 +++++++++++++-------- >>>> 1 file changed, 21 insertions(+), 12 deletions(-) >>>> >>>> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >>>> index 2433d3c29b49ff2..a5361153ca1d6a4 100644 >>>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >>>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >>>> @@ -858,11 +858,25 @@ static int arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu, >>>> return arm_smmu_cmdq_issue_cmdlist(smmu, cmd, 1, false); >>>> } >>>> >>>> -static int arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu) >>>> +static int __maybe_unused arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu) >>>> { >>>> return arm_smmu_cmdq_issue_cmdlist(smmu, NULL, 0, true); >>>> } >>>> >>>> +static int arm_smmu_cmdq_issue_cmd_with_sync(struct arm_smmu_device *smmu, >>>> + struct arm_smmu_cmdq_ent *ent) >>>> +{ >>>> + u64 cmd[CMDQ_ENT_DWORDS]; >>>> + >>>> + if (arm_smmu_cmdq_build_cmd(cmd, ent)) { >>>> + dev_warn(smmu->dev, "ignoring unknown CMDQ opcode 0x%x\n", >>>> + ent->opcode); >>>> + return -EINVAL; Are any of the errors returned from the "issue command" functions actually consumed? I couldn't see it on mainline code from a brief browse. >>>> + } >>>> + >>>> + return arm_smmu_cmdq_issue_cmdlist(smmu, cmd, 1, true); Thanks, John _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu