[PATCH v4 1/1 net-next] net: fec: add napi support to improve proformance
Frank Li
Frank.Li at freescale.com
Mon Jan 28 23:31:42 EST 2013
Add napi support
Before this patch
iperf -s -i 1
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 85.3 KByte (default)
------------------------------------------------------------
[ 4] local 10.192.242.153 port 5001 connected with 10.192.242.138 port 50004
[ ID] Interval Transfer Bandwidth
[ 4] 0.0- 1.0 sec 41.2 MBytes 345 Mbits/sec
[ 4] 1.0- 2.0 sec 43.7 MBytes 367 Mbits/sec
[ 4] 2.0- 3.0 sec 42.8 MBytes 359 Mbits/sec
[ 4] 3.0- 4.0 sec 43.7 MBytes 367 Mbits/sec
[ 4] 4.0- 5.0 sec 42.7 MBytes 359 Mbits/sec
[ 4] 5.0- 6.0 sec 43.8 MBytes 367 Mbits/sec
[ 4] 6.0- 7.0 sec 43.0 MBytes 361 Mbits/sec
After this patch
[ 4] 2.0- 3.0 sec 51.6 MBytes 433 Mbits/sec
[ 4] 3.0- 4.0 sec 51.8 MBytes 435 Mbits/sec
[ 4] 4.0- 5.0 sec 52.2 MBytes 438 Mbits/sec
[ 4] 5.0- 6.0 sec 52.1 MBytes 437 Mbits/sec
[ 4] 6.0- 7.0 sec 52.1 MBytes 437 Mbits/sec
[ 4] 7.0- 8.0 sec 52.3 MBytes 439 Mbits/sec
Signed-off-by: Frank Li <Frank.Li at freescale.com>
Signed-off-by: Fugang Duan <B38611 at freescale.com>
---
Change from v3 to v4
* remove lock to enable\disable rx irq. write expected reg value directly,
avoid read and write back.
Change from v2 to v3
* replace fec_enet_rx_int_is_enabled with fec_enet_rx_int_enable
* replace spin_lock_saveirq with spin_lock in irq handle
Change from v1 to v2
* Remove use_napi and napi_weight config. Support NAPI only.
* using napi_gro_receive replace netif_rx
drivers/net/ethernet/freescale/fec.c | 41 ++++++++++++++++++++++++++++-----
drivers/net/ethernet/freescale/fec.h | 2 +
2 files changed, 36 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c
index f52ba33..0287675 100644
--- a/drivers/net/ethernet/freescale/fec.c
+++ b/drivers/net/ethernet/freescale/fec.c
@@ -67,6 +67,7 @@
#endif
#define DRIVER_NAME "fec"
+#define FEC_NAPI_WEIGHT 64
/* Pause frame feild and FIFO threshold */
#define FEC_ENET_FCE (1 << 5)
@@ -168,6 +169,7 @@ MODULE_PARM_DESC(macaddr, "FEC Ethernet MAC address");
#define FEC_ENET_EBERR ((uint)0x00400000) /* SDMA bus error */
#define FEC_DEFAULT_IMASK (FEC_ENET_TXF | FEC_ENET_RXF | FEC_ENET_MII)
+#define FEC_RX_DISABLED_IMASK (FEC_DEFAULT_IMASK & (~FEC_ENET_RXF))
/* The FEC stores dest/src/type, data, and checksum for receive packets.
*/
@@ -656,8 +658,8 @@ fec_enet_tx(struct net_device *ndev)
* not been given to the system, we just set the empty indicator,
* effectively tossing the packet.
*/
-static void
-fec_enet_rx(struct net_device *ndev)
+static int
+fec_enet_rx(struct net_device *ndev, int budget)
{
struct fec_enet_private *fep = netdev_priv(ndev);
const struct platform_device_id *id_entry =
@@ -667,13 +669,12 @@ fec_enet_rx(struct net_device *ndev)
struct sk_buff *skb;
ushort pkt_len;
__u8 *data;
+ int pkt_received = 0;
#ifdef CONFIG_M532x
flush_cache_all();
#endif
- spin_lock(&fep->hw_lock);
-
/* First, grab all of the stats for the incoming packet.
* These get messed up if we get called due to a busy condition.
*/
@@ -681,6 +682,10 @@ fec_enet_rx(struct net_device *ndev)
while (!((status = bdp->cbd_sc) & BD_ENET_RX_EMPTY)) {
+ if (pkt_received >= budget)
+ break;
+ pkt_received++;
+
/* Since we have allocated space to hold a complete frame,
* the last indicator should be set.
*/
@@ -762,7 +767,7 @@ fec_enet_rx(struct net_device *ndev)
}
if (!skb_defer_rx_timestamp(skb))
- netif_rx(skb);
+ napi_gro_receive(&fep->napi, skb);
}
bdp->cbd_bufaddr = dma_map_single(&fep->pdev->dev, data,
@@ -796,7 +801,7 @@ rx_processing_done:
}
fep->cur_rx = bdp;
- spin_unlock(&fep->hw_lock);
+ return pkt_received;
}
static irqreturn_t
@@ -813,7 +818,13 @@ fec_enet_interrupt(int irq, void *dev_id)
if (int_events & FEC_ENET_RXF) {
ret = IRQ_HANDLED;
- fec_enet_rx(ndev);
+
+ /* Disable the RX interrupt */
+ if (napi_schedule_prep(&fep->napi)) {
+ writel(FEC_RX_DISABLED_IMASK,
+ fep->hwp + FEC_IMASK);
+ __napi_schedule(&fep->napi);
+ }
}
/* Transmit OK, or non-fatal error. Update the buffer
@@ -834,7 +845,18 @@ fec_enet_interrupt(int irq, void *dev_id)
return ret;
}
+static int fec_enet_rx_napi(struct napi_struct *napi, int budget)
+{
+ struct net_device *ndev = napi->dev;
+ int pkts = fec_enet_rx(ndev, budget);
+ struct fec_enet_private *fep = netdev_priv(ndev);
+ if (pkts < budget) {
+ napi_complete(napi);
+ writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);
+ }
+ return pkts;
+}
/* ------------------------------------------------------------------------- */
static void fec_get_mac(struct net_device *ndev)
@@ -1392,6 +1414,8 @@ fec_enet_open(struct net_device *ndev)
struct fec_enet_private *fep = netdev_priv(ndev);
int ret;
+ napi_enable(&fep->napi);
+
/* I should reset the ring buffers here, but I don't yet know
* a simple way to do that.
*/
@@ -1604,6 +1628,9 @@ static int fec_enet_init(struct net_device *ndev)
ndev->netdev_ops = &fec_netdev_ops;
ndev->ethtool_ops = &fec_enet_ethtool_ops;
+ writel(FEC_RX_DISABLED_IMASK, fep->hwp + FEC_IMASK);
+ netif_napi_add(ndev, &fep->napi, fec_enet_rx_napi, FEC_NAPI_WEIGHT);
+
/* Initialize the receive buffer descriptors. */
bdp = fep->rx_bd_base;
for (i = 0; i < RX_RING_SIZE; i++) {
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 2ebedaf..01579b8 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -249,6 +249,8 @@ struct fec_enet_private {
int bufdesc_ex;
int pause_flag;
+ struct napi_struct napi;
+
struct ptp_clock *ptp_clock;
struct ptp_clock_info ptp_caps;
unsigned long last_overflow_check;
--
1.7.1
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