net: thunderx: Support for page recycling
authorSunil Goutham <sgoutham@cavium.com>
Tue, 2 May 2017 13:06:50 +0000 (18:36 +0530)
committerDavid S. Miller <davem@davemloft.net>
Tue, 2 May 2017 19:41:20 +0000 (15:41 -0400)
commit5836b4429777bf57ca8fc02b154263aa54d97508
tree2a3878ca7264b93ecbfbd64d82dfd660d5c4055c
parentee0d8d8482345ff97a75a7d747efc309f13b0d80
net: thunderx: Support for page recycling

Adds support for page recycling for allocating receive buffers
to reduce cost of refilling RBDR ring. Also got rid of using
compound pages when pagesize is 4K, only order-0 pages now.

Only page is recycled, DMA mappings still needs to be done for
every receive buffer allocated due to following constraints
- Cannot have just one receive buffer per 64KB page.
- There is just one buffer ring shared across 8 Rx queues, so
  buffers of same page can go to any Rx queue.
- HW gives buffer address where packet has been DMA'ed and not
  the index into buffer ring.
This makes it not possible to resue DMA mapping info. So unfortunately
have to go through costly mapping route for every buffer.

Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/cavium/thunder/nic.h
drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c
drivers/net/ethernet/cavium/thunder/nicvf_queues.c
drivers/net/ethernet/cavium/thunder/nicvf_queues.h