Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760241AbYGRSy0 (ORCPT ); Fri, 18 Jul 2008 14:54:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756031AbYGRSyQ (ORCPT ); Fri, 18 Jul 2008 14:54:16 -0400 Received: from mga14.intel.com ([143.182.124.37]:32126 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755644AbYGRSyP (ORCPT ); Fri, 18 Jul 2008 14:54:15 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.31,211,1215414000"; d="scan'208";a="22097386" Subject: Re: [PATCH v2 3/4] I/OAT: tcp_dma_copybreak default value dependant onI/OAT version From: Dan Williams To: "Sosnowski, Maciej" Cc: "Nelson, Shannon" , linux-kernel@vger.kernel.org, netdev@vger.kernel.org In-Reply-To: <20080718152838.21235.78883.stgit@linux.site> References: <20080718152541.21235.85961.stgit@linux.site> <20080718152838.21235.78883.stgit@linux.site> Content-Type: text/plain Date: Fri, 18 Jul 2008 11:54:14 -0700 Message-Id: <1216407254.18755.4.camel@dwillia2-linux.ch.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-5.fc8) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2258 Lines: 77 On Fri, 2008-07-18 at 08:29 -0700, Sosnowski, Maciej wrote: > I/OAT DMA performance tuning showed different optimal values > of tcp_dma_copybreak for different I/OAT versions > (4096 for 1.2 and 2048 for 2.0). > This patch lets ioatdma driver set tcp_dma_copybreak value > according to these results. > > Signed-off-by: Maciej Sosnowski Let's kill some ifdef's... how about the following instead? diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c index 171cad6..1c0dafc 100644 --- a/drivers/dma/ioat_dma.c +++ b/drivers/dma/ioat_dma.c @@ -1330,6 +1330,8 @@ struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev, if (err) goto err_self_test; + ioat_set_tcp_copy_break(device); + dma_async_device_register(&device->common); return device; diff --git a/drivers/dma/ioatdma.h b/drivers/dma/ioatdma.h index f2c7fed..23e3196 100644 --- a/drivers/dma/ioatdma.h +++ b/drivers/dma/ioatdma.h @@ -27,6 +27,7 @@ #include #include #include +#include #define IOAT_DMA_VERSION "2.04" @@ -121,6 +122,20 @@ struct ioat_desc_sw { struct dma_async_tx_descriptor async_tx; }; +static inline void ioat_set_tcp_copy_break(struct ioatdma_device *dev) +{ + #ifdef CONFIG_NET_DMA + switch (dev->version) { + case IOAT_VER_1_2: + sysctl_tcp_dma_copybreak = 4096; + break; + case IOAT_VER_2_0: + sysctl_tcp_dma_copybreak = 2048; + break; + } + #endif +} + #if defined(CONFIG_INTEL_IOATDMA) || defined(CONFIG_INTEL_IOATDMA_MODULE) struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev, void __iomem *iobase); diff --git a/net/core/user_dma.c b/net/core/user_dma.c index 0ad1cd5..de76050 100644 --- a/net/core/user_dma.c +++ b/net/core/user_dma.c @@ -34,6 +34,7 @@ #define NET_DMA_DEFAULT_COPYBREAK 4096 int sysctl_tcp_dma_copybreak = NET_DMA_DEFAULT_COPYBREAK; +EXPORT_SYMBOL(sysctl_tcp_dma_copybreak); /** * dma_skb_copy_datagram_iovec - Copy a datagram to an iovec. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/