diff options
| author | Maciej Sosnowski <maciej.sosnowski@intel.com> | 2008-07-22 17:30:57 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2008-07-22 17:30:57 -0700 |
| commit | 16a37acaaf4aaa631ba3f83710ed6cdb1a597520 (patch) | |
| tree | 5826c763c70dc6b798c0d12216a80f4596dec284 | |
| parent | 09177e85d6a0bffac8b55afd28ed8b82bd873f0b (diff) | |
I/OAT: tcp_dma_copybreak default value dependent on I/OAT version
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.
[dan.j.williams@intel.com: remove some ifdefs]
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| -rw-r--r-- | drivers/dma/ioat_dma.c | 2 | ||||
| -rw-r--r-- | drivers/dma/ioatdma.h | 15 | ||||
| -rw-r--r-- | net/core/user_dma.c | 1 |
3 files changed, 18 insertions, 0 deletions
diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c index da572968a7d..ece5a0e3a33 100644 --- a/drivers/dma/ioat_dma.c +++ b/drivers/dma/ioat_dma.c @@ -1581,6 +1581,8 @@ 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); INIT_DELAYED_WORK(&device->work, ioat_dma_chan_watchdog); diff --git a/drivers/dma/ioatdma.h b/drivers/dma/ioatdma.h index c6ec933f989..685adb62aa5 100644 --- a/drivers/dma/ioatdma.h +++ b/drivers/dma/ioatdma.h @@ -27,6 +27,7 @@ #include <linux/dmapool.h> #include <linux/cache.h> #include <linux/pci_ids.h> +#include <net/tcp.h> #define IOAT_DMA_VERSION "2.18" @@ -129,6 +130,20 @@ 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 0ad1cd57bc3..de760504f6f 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. |