From dfff7144b14bab3d8baaeba8926fab371fa4a01e Mon Sep 17 00:00:00 2001 From: Simon Kagstrom Date: Wed, 25 Nov 2009 22:10:26 +0000 Subject: [PATCH] via-velocity: Implement NAPI support This patch adds NAPI support for VIA velocity. The new velocity_poll function also pairs tx/rx handling twice which improves perforamance on some workloads (e.g., netperf UDP_STREAM) significantly (that part is from the VIA driver). Signed-off-by: Simon Kagstrom Signed-off-by: David S. Miller --- drivers/net/via-velocity.c | 81 ++++++++++++++++++++++++++-------------------- drivers/net/via-velocity.h | 3 ++ 2 files changed, 49 insertions(+), 35 deletions(-) diff --git a/drivers/net/via-velocity.c b/drivers/net/via-velocity.c index 7c362b2..47b2882 100644 --- a/drivers/net/via-velocity.c +++ b/drivers/net/via-velocity.c @@ -354,12 +354,6 @@ VELOCITY_PARAM(ValPktLen, "Receiving or Drop invalid 802.3 frame"); */ VELOCITY_PARAM(wol_opts, "Wake On Lan options"); -#define INT_WORKS_DEF 20 -#define INT_WORKS_MIN 10 -#define INT_WORKS_MAX 64 - -VELOCITY_PARAM(int_works, "Number of packets per interrupt services"); - static int rx_copybreak = 200; module_param(rx_copybreak, int, 0644); MODULE_PARM_DESC(rx_copybreak, "Copy breakpoint for copy-only-tiny-frames"); @@ -503,7 +497,6 @@ static void __devinit velocity_get_options(struct velocity_opt *opts, int index, velocity_set_bool_opt(&opts->flags, ValPktLen[index], VAL_PKT_LEN_DEF, VELOCITY_FLAGS_VAL_PKT_LEN, "ValPktLen", devname); velocity_set_int_opt((int *) &opts->spd_dpx, speed_duplex[index], MED_LNK_MIN, MED_LNK_MAX, MED_LNK_DEF, "Media link mode", devname); velocity_set_int_opt((int *) &opts->wol_opts, wol_opts[index], WOL_OPT_MIN, WOL_OPT_MAX, WOL_OPT_DEF, "Wake On Lan options", devname); - velocity_set_int_opt((int *) &opts->int_works, int_works[index], INT_WORKS_MIN, INT_WORKS_MAX, INT_WORKS_DEF, "Interrupt service works", devname); opts->numrx = (opts->numrx & ~3); } @@ -2109,13 +2102,14 @@ static int velocity_receive_frame(struct velocity_info *vptr, int idx) * any received packets from the receive queue. Hand the ring * slots back to the adapter for reuse. */ -static int velocity_rx_srv(struct velocity_info *vptr, int status) +static int velocity_rx_srv(struct velocity_info *vptr, int status, + int budget_left) { struct net_device_stats *stats = &vptr->dev->stats; int rd_curr = vptr->rx.curr; int works = 0; - do { + while (works < budget_left) { struct rx_desc *rd = vptr->rx.ring + rd_curr; if (!vptr->rx.info[rd_curr].skb) @@ -2146,7 +2140,8 @@ static int velocity_rx_srv(struct velocity_info *vptr, int status) rd_curr++; if (rd_curr >= vptr->options.numrx) rd_curr = 0; - } while (++works <= 15); + works++; + } vptr->rx.curr = rd_curr; @@ -2157,6 +2152,40 @@ static int velocity_rx_srv(struct velocity_info *vptr, int status) return works; } +static int velocity_poll(struct napi_struct *napi, int budget) +{ + struct velocity_info *vptr = container_of(napi, + struct velocity_info, napi); + unsigned int rx_done; + u32 isr_status; + + spin_lock(&vptr->lock); + isr_status = mac_read_isr(vptr->mac_regs); + + /* Ack the interrupt */ + mac_write_isr(vptr->mac_regs, isr_status); + if (isr_status & (~(ISR_PRXI | ISR_PPRXI | ISR_PTXI | ISR_PPTXI))) + velocity_error(vptr, isr_status); + + /* + * Do rx and tx twice for performance (taken from the VIA + * out-of-tree driver). + */ + rx_done = velocity_rx_srv(vptr, isr_status, budget / 2); + velocity_tx_srv(vptr, isr_status); + rx_done += velocity_rx_srv(vptr, isr_status, budget - rx_done); + velocity_tx_srv(vptr, isr_status); + + spin_unlock(&vptr->lock); + + /* If budget not fully consumed, exit the polling mode */ + if (rx_done < budget) { + napi_complete(napi); + mac_enable_int(vptr->mac_regs); + } + + return rx_done; +} /** * velocity_intr - interrupt callback @@ -2173,8 +2202,6 @@ static irqreturn_t velocity_intr(int irq, void *dev_instance) struct net_device *dev = dev_instance; struct velocity_info *vptr = netdev_priv(dev); u32 isr_status; - int max_count = 0; - spin_lock(&vptr->lock); isr_status = mac_read_isr(vptr->mac_regs); @@ -2185,32 +2212,13 @@ static irqreturn_t velocity_intr(int irq, void *dev_instance) return IRQ_NONE; } - mac_disable_int(vptr->mac_regs); - - /* - * Keep processing the ISR until we have completed - * processing and the isr_status becomes zero - */ - - while (isr_status != 0) { - mac_write_isr(vptr->mac_regs, isr_status); - if (isr_status & (~(ISR_PRXI | ISR_PPRXI | ISR_PTXI | ISR_PPTXI))) - velocity_error(vptr, isr_status); - if (isr_status & (ISR_PRXI | ISR_PPRXI)) - max_count += velocity_rx_srv(vptr, isr_status); - if (isr_status & (ISR_PTXI | ISR_PPTXI)) - max_count += velocity_tx_srv(vptr, isr_status); - isr_status = mac_read_isr(vptr->mac_regs); - if (max_count > vptr->options.int_works) { - printk(KERN_WARNING "%s: excessive work at interrupt.\n", - dev->name); - max_count = 0; - } + if (likely(napi_schedule_prep(&vptr->napi))) { + mac_disable_int(vptr->mac_regs); + __napi_schedule(&vptr->napi); } spin_unlock(&vptr->lock); - mac_enable_int(vptr->mac_regs); - return IRQ_HANDLED; + return IRQ_HANDLED; } /** @@ -2250,6 +2258,7 @@ static int velocity_open(struct net_device *dev) mac_enable_int(vptr->mac_regs); netif_start_queue(dev); + napi_enable(&vptr->napi); vptr->flags |= VELOCITY_FLAGS_OPENED; out: return ret; @@ -2485,6 +2494,7 @@ static int velocity_close(struct net_device *dev) { struct velocity_info *vptr = netdev_priv(dev); + napi_disable(&vptr->napi); netif_stop_queue(dev); velocity_shutdown(vptr); @@ -2803,6 +2813,7 @@ static int __devinit velocity_found1(struct pci_dev *pdev, const struct pci_devi dev->irq = pdev->irq; dev->netdev_ops = &velocity_netdev_ops; dev->ethtool_ops = &velocity_ethtool_ops; + netif_napi_add(dev, &vptr->napi, velocity_poll, VELOCITY_NAPI_WEIGHT); dev->features |= NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_FILTER | NETIF_F_HW_VLAN_RX; diff --git a/drivers/net/via-velocity.h b/drivers/net/via-velocity.h index 499da64..d37a303 100644 --- a/drivers/net/via-velocity.h +++ b/drivers/net/via-velocity.h @@ -32,6 +32,7 @@ #define VELOCITY_VERSION "1.14" #define VELOCITY_IO_SIZE 256 +#define VELOCITY_NAPI_WEIGHT 64 #define PKT_BUF_SZ 1540 @@ -1562,6 +1563,8 @@ struct velocity_info { u32 ticks; u8 rev_id; + + struct napi_struct napi; }; /** -- 2.7.4