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=unavailable 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 76D64C4338F for ; Wed, 11 Aug 2021 02:18:31 +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 108BC60EBC for ; Wed, 11 Aug 2021 02:18:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 108BC60EBC 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-Transfer-Encoding:Content-Type: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=ZPI3hL56NuaW301XicgnXMcBgit7JYjdXzTi5oBeW10=; b=Dwh856JjhI9kc+5HEsqUS8KccN YX81uJdpynsZ7rvuCqUNqpABIlPriGO8RrJaLJA3MCWKX0V6Ccxocncx5xdInJ+PHOo/JQAtFW4Ps +f4yvyyrAimYEqSCERgqQF9u6mE6oJiGX8WqrXFjgcEgZAmtx5ZFGhHSOLK3lOVTKshWBSUpjJ4S8 4RIX3T6H3HGuLeptgOMxPDoDGUTOjExQXEzngHNEFcp9hrKHMr2uVARDDtFgj5Y4fu3K517Qu8g4y PuPr+5QPyOIC8T08dvtwN6HRuXs+7hqL2xTDNGyTGmaBGf970NFNTKRLj0vhSIKhVk7bBHyTz4y8c o6EMt4TQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mDdnV-005GsR-LX; Wed, 11 Aug 2021 02:16:49 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mDdnP-005GqY-8D for linux-arm-kernel@lists.infradead.org; Wed, 11 Aug 2021 02:16:46 +0000 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4GktdT5F3Nzb0kW; Wed, 11 Aug 2021 10:13:01 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggemv704-chm.china.huawei.com (10.3.19.47) 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 10:16:40 +0800 Received: from [10.174.179.0] (10.174.179.0) by dggpemm500006.china.huawei.com (7.185.36.236) 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 10:16:40 +0800 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 CC: Robin Murphy , Joerg Roedel , linux-arm-kernel , iommu , linux-kernel References: <20210626110130.2416-1-thunder.leizhen@huawei.com> <20210626110130.2416-3-thunder.leizhen@huawei.com> <20210810182454.GB3296@willie-the-truck> From: "Leizhen (ThunderTown)" Message-ID: Date: Wed, 11 Aug 2021 10:16:39 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20210810182454.GB3296@willie-the-truck> Content-Language: en-US X-Originating-IP: [10.174.179.0] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210810_191643_677878_7836CC39 X-CRM114-Status: GOOD ( 18.92 ) 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2021/8/11 2:24, Will Deacon wrote: > On Sat, Jun 26, 2021 at 07:01:24PM +0800, Zhen Lei wrote: >> The obvious key to the performance optimization of commit 587e6c10a7ce >> ("iommu/arm-smmu-v3: Reduce contention during command-queue insertion") is >> to allow multiple cores to insert commands in parallel after a brief mutex >> contention. >> >> 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; >> + } >> + >> + return arm_smmu_cmdq_issue_cmdlist(smmu, cmd, 1, true); >> +} > > This function is almost identical to arm_smmu_cmdq_issue_cmd(). How about > moving the guts out into a helper: > > static int __arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu, > struct arm_smmu_cmdq_ent *ent, > bool sync); > > and then having arm_smmu_cmdq_issue_cmd_with_sync() and > arm_smmu_cmdq_issue_cmd() wrap that? OK, I will do it. How about remove arm_smmu_cmdq_issue_sync()? It's unused now. > > Will > . > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel