From patchwork Mon May 6 09:48:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Lobakin X-Patchwork-Id: 13655225 X-Patchwork-Delegate: kuba@kernel.org Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 477B8143868; Mon, 6 May 2024 09:49:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.10 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714988971; cv=none; b=apeKb/+B+DLYVVS4GamUyyt1xwwK2ba4/Nm5K/O16LY00t/IRE2I3nYTdi26Im3UwQAhBN0ZMSj9mWV2gC0mjGmEo8Z6bA7+y4BGKfQ5c7VlWiv4YzUPZeQ4GurmM1vFWujM7+vJAo0WzlNbm+9UxwavXYpXVfSvyXV/VQNKsvE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714988971; c=relaxed/simple; bh=3SgiWVroz4YClWohZTqvdSQuz6xJr9Rgf0K+w7Mn7ZE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ywwrr+LBkLIMdoHiNYZis3MUrXr/ulXJrQEUzgYTLc2I7nSTPIdXFdbGDjKi2Dcq1dl0T7z1V2JWPspJSH82SyzpwzN5gFs8oESQEo0CpaIrG1o10B67yJWqdXmMSd90hwXb7nJK+m3PV5L0PXMYUciBzludyWI5yTHS0rt3y/U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=kXEEd7OK; arc=none smtp.client-ip=198.175.65.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="kXEEd7OK" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1714988969; x=1746524969; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=3SgiWVroz4YClWohZTqvdSQuz6xJr9Rgf0K+w7Mn7ZE=; b=kXEEd7OKRhLKvMJuxRfRm0Qed1xLZl00yjm9kWItOhiFMGWYJCunAahf QwFKMSPYv7AN2+Rl9nKw/0icSXDb5y+LihuF257Tkl7nMRw5Kevsn297W fz+kFCFjxCoDr1hZmhPI7gtiNZ2mqfuX+pwCT7g87z6JC4ZPGVQhCN9Ln TJnLhUIzURy5lUihN4e+HwR7viesufU7uOU7koojkJqCkmcNjCFkoyt11 DDNZ2imvMPuvlA7TcHqPlsInlshNcTDqQDA/ek7P9imvk/yfqgKVXBcCV Oz5/tWEVkApwsj94kmglLb4sLRDahYQjeX+PR3L6F16WwYzMRcOUpXswz Q==; X-CSE-ConnectionGUID: MsB/4bfkSYuuRtVwD3LR/w== X-CSE-MsgGUID: pGQ2QA3LRLqAvmWAWQM3YA== X-IronPort-AV: E=McAfee;i="6600,9927,11064"; a="28200991" X-IronPort-AV: E=Sophos;i="6.07,258,1708416000"; d="scan'208";a="28200991" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 May 2024 02:49:29 -0700 X-CSE-ConnectionGUID: ZTRtr7BBRfaWt5suCIJygw== X-CSE-MsgGUID: b5c56w65T9GGcO0TMm1YGA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,258,1708416000"; d="scan'208";a="58995722" Received: from newjersey.igk.intel.com ([10.102.20.203]) by orviesa002.jf.intel.com with ESMTP; 06 May 2024 02:49:25 -0700 From: Alexander Lobakin To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Alexander Lobakin , Christoph Hellwig , Marek Szyprowski , Robin Murphy , Joerg Roedel , Will Deacon , "Rafael J. Wysocki" , Magnus Karlsson , nex.sw.ncis.osdt.itp.upstreaming@intel.com, bpf@vger.kernel.org, netdev@vger.kernel.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH net-next v5 3/7] iommu/dma: avoid expensive indirect calls for sync operations Date: Mon, 6 May 2024 11:48:51 +0200 Message-ID: <20240506094855.12944-4-aleksander.lobakin@intel.com> X-Mailer: git-send-email 2.45.0 In-Reply-To: <20240506094855.12944-1-aleksander.lobakin@intel.com> References: <20240506094855.12944-1-aleksander.lobakin@intel.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org When IOMMU is on, the actual synchronization happens in the same cases as with the direct DMA. Advertise %DMA_F_CAN_SKIP_SYNC in IOMMU DMA to skip sync ops calls (indirect) for non-SWIOTLB buffers. perf profile before the patch: 18.53% [kernel] [k] gq_rx_skb 14.77% [kernel] [k] napi_reuse_skb 8.95% [kernel] [k] skb_release_data 5.42% [kernel] [k] dev_gro_receive 5.37% [kernel] [k] memcpy <*> 5.26% [kernel] [k] iommu_dma_sync_sg_for_cpu 4.78% [kernel] [k] tcp_gro_receive <*> 4.42% [kernel] [k] iommu_dma_sync_sg_for_device 4.12% [kernel] [k] ipv6_gro_receive 3.65% [kernel] [k] gq_pool_get 3.25% [kernel] [k] skb_gro_receive 2.07% [kernel] [k] napi_gro_frags 1.98% [kernel] [k] tcp6_gro_receive 1.27% [kernel] [k] gq_rx_prep_buffers 1.18% [kernel] [k] gq_rx_napi_handler 0.99% [kernel] [k] csum_partial 0.74% [kernel] [k] csum_ipv6_magic 0.72% [kernel] [k] free_pcp_prepare 0.60% [kernel] [k] __napi_poll 0.58% [kernel] [k] net_rx_action 0.56% [kernel] [k] read_tsc <*> 0.50% [kernel] [k] __x86_indirect_thunk_r11 0.45% [kernel] [k] memset After patch, lines with <*> no longer show up, and overall cpu usage looks much better (~60% instead of ~72%): 25.56% [kernel] [k] gq_rx_skb 9.90% [kernel] [k] napi_reuse_skb 7.39% [kernel] [k] dev_gro_receive 6.78% [kernel] [k] memcpy 6.53% [kernel] [k] skb_release_data 6.39% [kernel] [k] tcp_gro_receive 5.71% [kernel] [k] ipv6_gro_receive 4.35% [kernel] [k] napi_gro_frags 4.34% [kernel] [k] skb_gro_receive 3.50% [kernel] [k] gq_pool_get 3.08% [kernel] [k] gq_rx_napi_handler 2.35% [kernel] [k] tcp6_gro_receive 2.06% [kernel] [k] gq_rx_prep_buffers 1.32% [kernel] [k] csum_partial 0.93% [kernel] [k] csum_ipv6_magic 0.65% [kernel] [k] net_rx_action iavf yields +10% of Mpps on Rx. This also unblocks batched allocations of XSk buffers when IOMMU is active. Co-developed-by: Eric Dumazet Signed-off-by: Eric Dumazet Acked-by: Robin Murphy Signed-off-by: Alexander Lobakin --- drivers/iommu/dma-iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index e4cb26f6a943..0516e3e859b5 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1720,7 +1720,8 @@ static size_t iommu_dma_max_mapping_size(struct device *dev) } static const struct dma_map_ops iommu_dma_ops = { - .flags = DMA_F_PCI_P2PDMA_SUPPORTED, + .flags = DMA_F_PCI_P2PDMA_SUPPORTED | + DMA_F_CAN_SKIP_SYNC, .alloc = iommu_dma_alloc, .free = iommu_dma_free, .alloc_pages = dma_common_alloc_pages,