[PATCH 1/2 net-next] net: fec: add napi support to improve proformance
Frank Li
Frank.Li at freescale.com
Tue Jan 22 23:12:10 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>
---
drivers/net/ethernet/freescale/fec.c | 68 ++++++++++++++++++++++++++++++---
drivers/net/ethernet/freescale/fec.h | 4 ++
2 files changed, 65 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c
index f52ba33..8fa420c 100644
--- a/drivers/net/ethernet/freescale/fec.c
+++ b/drivers/net/ethernet/freescale/fec.c
@@ -67,6 +67,8 @@
#endif
#define DRIVER_NAME "fec"
+#define FEC_NAPI_WEIGHT 64
+#define INT32_MAX 0x7FFFFFFF
/* Pause frame feild and FIFO threshold */
#define FEC_ENET_FCE (1 << 5)
@@ -565,6 +567,20 @@ fec_timeout(struct net_device *ndev)
}
static void
+fec_enet_rx_int_is_enabled(struct net_device *ndev, bool enabled)
+{
+ struct fec_enet_private *fep = netdev_priv(ndev);
+ uint int_events;
+
+ int_events = readl(fep->hwp + FEC_IMASK);
+ if (enabled)
+ int_events |= FEC_ENET_RXF;
+ else
+ int_events &= ~FEC_ENET_RXF;
+ writel(int_events, fep->hwp + FEC_IMASK);
+}
+
+static void
fec_enet_tx(struct net_device *ndev)
{
struct fec_enet_private *fep;
@@ -656,8 +672,8 @@ 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 +683,12 @@ 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 +696,10 @@ 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.
*/
@@ -796,7 +815,7 @@ rx_processing_done:
}
fep->cur_rx = bdp;
- spin_unlock(&fep->hw_lock);
+ return pkt_received;
}
static irqreturn_t
@@ -805,6 +824,7 @@ fec_enet_interrupt(int irq, void *dev_id)
struct net_device *ndev = dev_id;
struct fec_enet_private *fep = netdev_priv(ndev);
uint int_events;
+ ulong flags;
irqreturn_t ret = IRQ_NONE;
do {
@@ -813,7 +833,18 @@ fec_enet_interrupt(int irq, void *dev_id)
if (int_events & FEC_ENET_RXF) {
ret = IRQ_HANDLED;
- fec_enet_rx(ndev);
+ spin_lock_irqsave(&fep->hw_lock, flags);
+
+ if (fep->use_napi) {
+ /* Disable the RX interrupt */
+ if (napi_schedule_prep(&fep->napi)) {
+ fec_enet_rx_int_is_enabled(ndev, false);
+ __napi_schedule(&fep->napi);
+ }
+ } else
+ fec_enet_rx(ndev, INT32_MAX);
+
+ spin_unlock_irqrestore(&fep->hw_lock, flags);
}
/* Transmit OK, or non-fatal error. Update the buffer
@@ -834,7 +865,16 @@ 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 pkgs = fec_enet_rx(ndev, budget);
+ if (pkgs < budget) {
+ napi_complete(napi);
+ fec_enet_rx_int_is_enabled(ndev, true);
+ }
+ return pkgs;
+}
/* ------------------------------------------------------------------------- */
static void fec_get_mac(struct net_device *ndev)
@@ -1392,6 +1432,9 @@ fec_enet_open(struct net_device *ndev)
struct fec_enet_private *fep = netdev_priv(ndev);
int ret;
+ if (fep->use_napi)
+ 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 +1647,11 @@ static int fec_enet_init(struct net_device *ndev)
ndev->netdev_ops = &fec_netdev_ops;
ndev->ethtool_ops = &fec_enet_ethtool_ops;
+ if (fep->use_napi) {
+ fec_enet_rx_int_is_enabled(ndev, false);
+ netif_napi_add(ndev, &fep->napi, fec_enet_rx_napi, fep->napi_weight);
+ }
+
/* Initialize the receive buffer descriptors. */
bdp = fep->rx_bd_base;
for (i = 0; i < RX_RING_SIZE; i++) {
@@ -1698,6 +1746,7 @@ fec_probe(struct platform_device *pdev)
static int dev_id;
struct pinctrl *pinctrl;
struct regulator *reg_phy;
+ struct device_node *np = pdev->dev.of_node;
of_id = of_match_device(fec_dt_ids, &pdev->dev);
if (of_id)
@@ -1811,6 +1860,11 @@ fec_probe(struct platform_device *pdev)
}
}
+ fep->use_napi = !of_property_read_bool(np, "disable_napi");
+
+ if (of_property_read_u32(np, "napi_weight", &fep->napi_weight))
+ fep->napi_weight = FEC_NAPI_WEIGHT; /*using default value*/
+
fec_reset_phy(pdev);
ret = fec_enet_init(ndev);
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 2ebedaf..31fcdd0 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -249,6 +249,10 @@ struct fec_enet_private {
int bufdesc_ex;
int pause_flag;
+ struct napi_struct napi;
+ int napi_weight;
+ bool use_napi;
+
struct ptp_clock *ptp_clock;
struct ptp_clock_info ptp_caps;
unsigned long last_overflow_check;
--
1.7.1
More information about the linux-arm-kernel
mailing list