| Message ID | 1359077343-8271-1-git-send-email-Frank.Li@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jan 25, 2013 at 09:29:03AM +0800, Frank Li wrote: [...] > static void > +fec_enet_rx_int_enable(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); > +} You hold your hw_lock when this is called to disable the interrupt, but not when you re-enable it. See below. [...] > @@ -813,7 +831,14 @@ fec_enet_interrupt(int irq, void *dev_id) > > if (int_events & FEC_ENET_RXF) { > ret = IRQ_HANDLED; > - fec_enet_rx(ndev); > + > + spin_lock(&fep->hw_lock); > + /* Disable the RX interrupt */ > + if (napi_schedule_prep(&fep->napi)) { > + fec_enet_rx_int_enable(ndev, false); > + __napi_schedule(&fep->napi); > + } > + spin_unlock(&fep->hw_lock); > } > > /* Transmit OK, or non-fatal error. Update the buffer > @@ -834,7 +859,16 @@ 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_enable(ndev, true); Here you're not locking when re-enabling, but you do in the disable path. Also, when you're disabling interrupts above, you're doing that in your HW interrupt handler, you should be using spin_lock_irqsave()/irq_restore(). Cheers, -PJ
2013/1/25 Waskiewicz Jr, Peter P <peter.p.waskiewicz.jr@intel.com>: > On Fri, Jan 25, 2013 at 09:29:03AM +0800, Frank Li wrote: > > [...] > >> static void >> +fec_enet_rx_int_enable(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); >> +} > > You hold your hw_lock when this is called to disable the interrupt, but > not when you re-enable it. See below. > > [...] > >> @@ -813,7 +831,14 @@ fec_enet_interrupt(int irq, void *dev_id) >> >> if (int_events & FEC_ENET_RXF) { >> ret = IRQ_HANDLED; >> - fec_enet_rx(ndev); >> + >> + spin_lock(&fep->hw_lock); >> + /* Disable the RX interrupt */ >> + if (napi_schedule_prep(&fep->napi)) { >> + fec_enet_rx_int_enable(ndev, false); >> + __napi_schedule(&fep->napi); >> + } >> + spin_unlock(&fep->hw_lock); >> } >> >> /* Transmit OK, or non-fatal error. Update the buffer >> @@ -834,7 +859,16 @@ 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_enable(ndev, true); > > Here you're not locking when re-enabling, but you do in the disable path. > > Also, when you're disabling interrupts above, you're doing that in your > HW interrupt handler, you should be using spin_lock_irqsave()/irq_restore(). Good catch. Thanks! > > Cheers, > -PJ
Waskiewicz Jr, Peter P <peter.p.waskiewicz.jr@intel.com> : [...] > Also, when you're disabling interrupts above, you're doing that in your > HW interrupt handler, you should be using spin_lock_irqsave()/irq_restore(). Does the platform forbid to defer FEC_EIR / FEC_IEVENT write to the napi poll handler and only disable the irq through FEC_EIMR / FEC_IMASK in fec_enet_interrupt so as to remove the spinlock ? (Frank, please keep an empty line between variables declarations and function body).
2013/1/26 Francois Romieu <romieu@fr.zoreil.com>: > Waskiewicz Jr, Peter P <peter.p.waskiewicz.jr@intel.com> : > [...] >> Also, when you're disabling interrupts above, you're doing that in your >> HW interrupt handler, you should be using spin_lock_irqsave()/irq_restore(). > > Does the platform forbid to defer FEC_EIR / FEC_IEVENT write to the napi I can clean FEC_IEVENT, but rx irq still issue if new package received. I tested, performance drop if just clean FEC_IEVENT > poll handler and only disable the irq through FEC_EIMR / FEC_IMASK in > fec_enet_interrupt so as to remove the spinlock ? I can remove this spin lock in other way. I will send new patch. > > (Frank, please keep an empty line between variables declarations and > function body). Okay. > > -- > Ueimor
diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c index f52ba33..1d9e019 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) @@ -565,6 +566,20 @@ fec_timeout(struct net_device *ndev) } static void +fec_enet_rx_int_enable(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 +671,8 @@ 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 +682,12 @@ 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 +695,10 @@ 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 +780,7 @@ 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 +814,7 @@ rx_processing_done: } fep->cur_rx = bdp; - spin_unlock(&fep->hw_lock); + return pkt_received; } static irqreturn_t @@ -813,7 +831,14 @@ fec_enet_interrupt(int irq, void *dev_id) if (int_events & FEC_ENET_RXF) { ret = IRQ_HANDLED; - fec_enet_rx(ndev); + + spin_lock(&fep->hw_lock); + /* Disable the RX interrupt */ + if (napi_schedule_prep(&fep->napi)) { + fec_enet_rx_int_enable(ndev, false); + __napi_schedule(&fep->napi); + } + spin_unlock(&fep->hw_lock); } /* Transmit OK, or non-fatal error. Update the buffer @@ -834,7 +859,16 @@ 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_enable(ndev, true); + } + return pkgs; +} /* ------------------------------------------------------------------------- */ static void fec_get_mac(struct net_device *ndev) @@ -1392,6 +1426,8 @@ 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 +1640,9 @@ static int fec_enet_init(struct net_device *ndev) ndev->netdev_ops = &fec_netdev_ops; ndev->ethtool_ops = &fec_enet_ethtool_ops; + fec_enet_rx_int_enable(ndev, false); + 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;