On 01/19/2013 03:23 AM, Craig Hada wrote:
This patch sets the coherent DMA mask to 64-bit after the be2net driver has been acknowledged that the system is 64-bit DMA capable. The coherent DMA mask is examined by the Intel IOMMU driver to determine whether to allow pass through context mapping for all devices. With this patch, the be2net driver combined with be2net compatible hardware provides comparable performance to the case where vt-d is disabled. The main use case for this change is to decrease the time necessary to copy virtual machine memory during KVM live migration instantiations.This patch was tested on a system that enables the IOMMU in non-coherent mode. Two DMA remapper issues were encountered in the previous version and both patches have been committed. commit ea2447f700cab264019b52e2b417d689e052dcfd commit 2e12bc29fc5a12242d68e11875db3dd58efad9ff Signed-off-by: Craig Hada <craig.h...@hp.com> --- drivers/net/ethernet/emulex/benet/be_main.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c index 9dca22b..b507e99 100644 --- a/drivers/net/ethernet/emulex/benet/be_main.c +++ b/drivers/net/ethernet/emulex/benet/be_main.c @@ -4052,6 +4052,12 @@ static int be_probe(struct pci_dev *pdev, const struct pci_device_id *pdev_id) status = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)); if (!status) { + status = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64)); + if (status < 0) { + dev_err(&pdev->dev, + "dma_set_coherent_mask failed, aborting\n"); + goto free_netdev; + } netdev->features |= NETIF_F_HIGHDMA; } else { status = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
Dave, I'd like to ask when do you plan to apply this patch? Thanks, Ivan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
