net: thunderx: Optimize RBDR descriptor handling
Receive buffer's physical address or iova will anyway not
go beyond 49bits, since it is the max supported HW address.
As per perf, updating bitfields i.e buf_addr:42 in RBDR
descriptor entry consumes lots of cpu cycles, hence changed
it to a 64bit field with alignment requirements taken care of.
Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
index 12f9709..dfc85a1 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -257,7 +257,7 @@ static int nicvf_init_rbdr(struct nicvf *nic, struct rbdr *rbdr,
}
desc = GET_RBDR_DESC(rbdr, idx);
- desc->buf_addr = (u64)rbuf >> NICVF_RCV_BUF_ALIGN;
+ desc->buf_addr = (u64)rbuf & ~(NICVF_RCV_BUF_ALIGN_BYTES - 1);
}
nicvf_get_page(nic);
@@ -286,7 +286,7 @@ static void nicvf_free_rbdr(struct nicvf *nic, struct rbdr *rbdr)
/* Release page references */
while (head != tail) {
desc = GET_RBDR_DESC(rbdr, head);
- buf_addr = ((u64)desc->buf_addr) << NICVF_RCV_BUF_ALIGN;
+ buf_addr = desc->buf_addr;
phys_addr = nicvf_iova_to_phys(nic, buf_addr);
dma_unmap_page_attrs(&nic->pdev->dev, buf_addr, RCV_FRAG_LEN,
DMA_FROM_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
@@ -297,7 +297,7 @@ static void nicvf_free_rbdr(struct nicvf *nic, struct rbdr *rbdr)
}
/* Release buffer of tail desc */
desc = GET_RBDR_DESC(rbdr, tail);
- buf_addr = ((u64)desc->buf_addr) << NICVF_RCV_BUF_ALIGN;
+ buf_addr = desc->buf_addr;
phys_addr = nicvf_iova_to_phys(nic, buf_addr);
dma_unmap_page_attrs(&nic->pdev->dev, buf_addr, RCV_FRAG_LEN,
DMA_FROM_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
@@ -364,7 +364,7 @@ static void nicvf_refill_rbdr(struct nicvf *nic, gfp_t gfp)
break;
desc = GET_RBDR_DESC(rbdr, tail);
- desc->buf_addr = (u64)rbuf >> NICVF_RCV_BUF_ALIGN;
+ desc->buf_addr = (u64)rbuf & ~(NICVF_RCV_BUF_ALIGN_BYTES - 1);
refill_rb_cnt--;
new_rb++;
}