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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 580A2C4338F for ; Wed, 11 Aug 2021 10:33:41 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 1EDDD60C3E for ; Wed, 11 Aug 2021 10:33:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1EDDD60C3E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:CC:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GSENR98Nl7PRDdhZWGlEyWY2V4Fd+d7gK1MchnahEAM=; b=qXuEzaHIg51vMTHYZ76SU7eqv5 CNhSrSMxg/4yrmzs0OcpESkWXZxcBFw4vK7KoJxUsaXrXfIG7HUcGxyo5VOfEgK7QNxfQFonpycti f+Ic0Hl3S5S6FzXfH4b73n/yizr8ow4ZOdJ57U70BdKDVHXaKvKTd7dLPPhtOcSuPcnGHjL0R3qp1 UHUprXMqX12BALf+R6EtQjpbghwulcmmX0TZ0nTVVSgI+GppS6z28kfo8X6yO0MUg7cfk5Dr2ldcP USyy4JVrZbZE/RC7L0TeUn3Yyuy/W20Y67CnsGlGJJQr0dWiZVkjoiF1FK43FBPN4nCY5ecfMD0Rn n9EJaZVA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mDlWu-006dk8-2Y; Wed, 11 Aug 2021 10:32:12 +0000 Received: from frasgout.his.huawei.com ([185.176.79.56]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mDlWY-006dbW-Ug for linux-arm-kernel@lists.infradead.org; Wed, 11 Aug 2021 10:31:53 +0000 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)" CC: Robin Murphy , iommu , linux-arm-kernel , linux-kernel 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210811_033151_197615_EF4B25DC X-CRM114-Status: GOOD ( 11.62 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org >>>> 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel