virtio_net: enable premapped mode for merge and small by default

Currently, the virtio core will perform a dma operation for each
buffer. Although, the same page may be operated multiple times.

In premapped mod, we can perform only one dma operation for the pages of
the alloc frag. This is beneficial for the iommu device.

kernel command line: intel_iommu=on iommu.passthrough=0

       |  strict=0  | strict=1
Before |  775496pps | 428614pps
After  | 1109316pps | 742853pps

In the 6.11, we disabled this feature because a regress [1].

Now, we fix the problem and re-enable it.

[1]: http://lore.kernel.org/all/[email protected]

Tested-by: Darren Kenny <[email protected]>
Signed-off-by: Xuan Zhuo <[email protected]>
Acked-by: Jason Wang <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>

0 files changed, 0 insertions, 0 deletions