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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 0F60EC432BE for ; Wed, 11 Aug 2021 15:54:28 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 7CE2A60FD9 for ; Wed, 11 Aug 2021 15:54:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7CE2A60FD9 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 smtp4.osuosl.org (Postfix) with ESMTP id 3C81B40175; Wed, 11 Aug 2021 15:54:27 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id hn3kKFzRBcc6; Wed, 11 Aug 2021 15:54:23 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTPS id 0A23640570; Wed, 11 Aug 2021 15:54:23 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id D6B4CC0010; Wed, 11 Aug 2021 15:54:22 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [IPv6:2605:bc80:3010::133]) by lists.linuxfoundation.org (Postfix) with ESMTP id A3F6EC000E for ; Wed, 11 Aug 2021 15:54:21 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 9248F40163 for ; Wed, 11 Aug 2021 15:54:21 +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 5RlDCO7UNyJy for ; Wed, 11 Aug 2021 15:54:20 +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 smtp2.osuosl.org (Postfix) with ESMTPS id 28142400FC for ; Wed, 11 Aug 2021 15:54:20 +0000 (UTC) Received: from fraeml705-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4GlDrP41YTz6G9PZ; Wed, 11 Aug 2021 23:53:41 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml705-chm.china.huawei.com (10.206.15.54) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.8; Wed, 11 Aug 2021 17:54:16 +0200 Received: from localhost.localdomain (10.69.192.58) 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 16:54:14 +0100 From: John Garry To: , Subject: [PATCH] iommu/arm-smmu-v3: Stop pre-zeroing batch commands Date: Wed, 11 Aug 2021 23:49:26 +0800 Message-ID: <1628696966-88386-1-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Cc: linuxarm@huawei.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Pre-zeroing the batched commands structure is inefficient, as individual commands are zeroed later in arm_smmu_cmdq_build_cmd(). The size is quite large and commonly most commands won't even be used: struct arm_smmu_cmdq_batch cmds = {}; 345c: 52800001 mov w1, #0x0 // #0 3460: d2808102 mov x2, #0x408 // #1032 3464: 910143a0 add x0, x29, #0x50 3468: 94000000 bl 0 Stop pre-zeroing the complete structure and only zero the num member. Signed-off-by: John Garry 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 cbc57edfa4e2..2a4f3fb938f6 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -1082,7 +1082,7 @@ static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain, size_t i; unsigned long flags; struct arm_smmu_master *master; - struct arm_smmu_cmdq_batch cmds = {}; + struct arm_smmu_cmdq_batch cmds; struct arm_smmu_device *smmu = smmu_domain->smmu; struct arm_smmu_cmdq_ent cmd = { .opcode = CMDQ_OP_CFGI_CD, @@ -1092,6 +1092,8 @@ static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain, }, }; + cmds.num = 0; + spin_lock_irqsave(&smmu_domain->devices_lock, flags); list_for_each_entry(master, &smmu_domain->devices, domain_head) { for (i = 0; i < master->num_streams; i++) { @@ -1908,7 +1910,7 @@ int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain, int ssid, unsigned long flags; struct arm_smmu_cmdq_ent cmd; struct arm_smmu_master *master; - struct arm_smmu_cmdq_batch cmds = {}; + struct arm_smmu_cmdq_batch cmds; if (!(smmu_domain->smmu->features & ARM_SMMU_FEAT_ATS)) return 0; @@ -1932,6 +1934,8 @@ int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain, int ssid, arm_smmu_atc_inv_to_cmd(ssid, iova, size, &cmd); + cmds.num = 0; + spin_lock_irqsave(&smmu_domain->devices_lock, flags); list_for_each_entry(master, &smmu_domain->devices, domain_head) { if (!master->ats_enabled) @@ -1980,7 +1984,7 @@ static void __arm_smmu_tlb_inv_range(struct arm_smmu_cmdq_ent *cmd, struct arm_smmu_device *smmu = smmu_domain->smmu; unsigned long end = iova + size, num_pages = 0, tg = 0; size_t inv_range = granule; - struct arm_smmu_cmdq_batch cmds = {}; + struct arm_smmu_cmdq_batch cmds; if (!size) return; @@ -1998,6 +2002,8 @@ static void __arm_smmu_tlb_inv_range(struct arm_smmu_cmdq_ent *cmd, num_pages = size >> tg; } + cmds.num = 0; + while (iova < end) { if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) { /* -- 2.26.2 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu