Merge branch 'netsec-driver-improvements'

Ilias Apalodimas says:

====================
netsec driver improvements

This patchset introduces some improvements on socionext netsec driver.
 - patch 1/2, avoids unneeded MMIO reads on the Rx path
 - patch 2/2, is adjusting the numbers of descriptors used

Changes since v1:
 - Move dma_rmb() to protect descriptor accesses until the device
 has updated the NETSEC_RX_PKT_OWN_FIELD bit
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2018-08-11 12:11:36 -07:00
commit 8a8982d1e2

View File

@ -232,8 +232,7 @@
#define NETSEC_EEPROM_PKT_ME_ADDRESS 0x20
#define NETSEC_EEPROM_PKT_ME_SIZE 0x24
#define DESC_NUM 128
#define NAPI_BUDGET (DESC_NUM / 2)
#define DESC_NUM 256
#define DESC_SZ sizeof(struct netsec_de)
@ -642,8 +641,6 @@ static struct sk_buff *netsec_get_rx_pkt_data(struct netsec_priv *priv,
tmp_skb = netsec_alloc_skb(priv, &td);
dma_rmb();
tail = dring->tail;
if (!tmp_skb) {
@ -657,8 +654,6 @@ static struct sk_buff *netsec_get_rx_pkt_data(struct netsec_priv *priv,
/* move tail ahead */
dring->tail = (dring->tail + 1) % DESC_NUM;
dring->pkt_cnt--;
return skb;
}
@ -731,25 +726,24 @@ static int netsec_process_rx(struct netsec_priv *priv, int budget)
struct netsec_desc_ring *dring = &priv->desc_ring[NETSEC_RING_RX];
struct net_device *ndev = priv->ndev;
struct netsec_rx_pkt_info rx_info;
int done = 0, rx_num = 0;
int done = 0;
struct netsec_desc desc;
struct sk_buff *skb;
u16 len;
while (done < budget) {
if (!rx_num) {
rx_num = netsec_read(priv, NETSEC_REG_NRM_RX_PKTCNT);
dring->pkt_cnt += rx_num;
u16 idx = dring->tail;
struct netsec_de *de = dring->vaddr + (DESC_SZ * idx);
/* move head 'rx_num' */
dring->head = (dring->head + rx_num) % DESC_NUM;
if (de->attr & (1U << NETSEC_RX_PKT_OWN_FIELD))
break;
rx_num = dring->pkt_cnt;
if (!rx_num)
break;
}
/* This barrier is needed to keep us from reading
* any other fields out of the netsec_de until we have
* verified the descriptor has been written back
*/
dma_rmb();
done++;
rx_num--;
skb = netsec_get_rx_pkt_data(priv, &rx_info, &desc, &len);
if (unlikely(!skb) || rx_info.err_flag) {
netif_err(priv, drv, priv->ndev,
@ -1664,7 +1658,7 @@ static int netsec_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "hardware revision %d.%d\n",
hw_ver >> 16, hw_ver & 0xffff);
netif_napi_add(ndev, &priv->napi, netsec_napi_poll, NAPI_BUDGET);
netif_napi_add(ndev, &priv->napi, netsec_napi_poll, NAPI_POLL_WEIGHT);
ndev->netdev_ops = &netsec_netdev_ops;
ndev->ethtool_ops = &netsec_ethtool_ops;