From: raghavendra.koushik@neterion.com Date: Wed, 3 Aug 2005 19:32:00 +0000 (-0700) Subject: [PATCH] S2io: Performance improvements X-Git-Tag: v2.6.14-rc1~1055^2~40 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fe113638328995b69d8797e6466b29661b1602d1;p=linux-2.6 [PATCH] S2io: Performance improvements Hi, This patch relates to mostly performance related changes. 1. Fixed incorrect computation of PANIC level in rx_buffer_level(). 2. Removed unnecessary PIOs(read/write of tx_traffic_int and rx_traffic_int) from interrupt handler and removed read of general_int_status register from xmit routine. 3. Enable two-buffer mode(for Rx path) automatically for SGI systems. This improves Rx performance dramatically on SGI systems. Signed-off-by: Ravinandan Arakali Signed-off-by: Raghavendra Koushik Signed-off-by: Jeff Garzik --- diff --git a/drivers/net/s2io.c b/drivers/net/s2io.c index 6668b99025..28d6d3746c 100644 --- a/drivers/net/s2io.c +++ b/drivers/net/s2io.c @@ -100,8 +100,7 @@ static inline int rx_buffer_level(nic_t * sp, int rxb_size, int ring) mac_control = &sp->mac_control; if ((mac_control->rings[ring].pkt_cnt - rxb_size) > 16) { level = LOW; - if ((mac_control->rings[ring].pkt_cnt - rxb_size) < - MAX_RXDS_PER_BLOCK) { + if (rxb_size <= MAX_RXDS_PER_BLOCK) { level = PANIC; } } @@ -2193,7 +2192,6 @@ static void rx_intr_handler(ring_info_t *ring_data) { nic_t *nic = ring_data->nic; struct net_device *dev = (struct net_device *) nic->dev; - XENA_dev_config_t __iomem *bar0 = nic->bar0; int get_block, get_offset, put_block, put_offset, ring_bufs; rx_curr_get_info_t get_info, put_info; RxD_t *rxdp; @@ -2201,8 +2199,6 @@ static void rx_intr_handler(ring_info_t *ring_data) #ifndef CONFIG_S2IO_NAPI int pkt_cnt = 0; #endif - register u64 val64; - spin_lock(&nic->rx_lock); if (atomic_read(&nic->card_state) == CARD_DOWN) { DBG_PRINT(ERR_DBG, "%s: %s going down for reset\n", @@ -2210,13 +2206,6 @@ static void rx_intr_handler(ring_info_t *ring_data) spin_unlock(&nic->rx_lock); } - /* - * rx_traffic_int reg is an R1 register, hence we read and write - * back the same value in the register to clear it - */ - val64 = readq(&bar0->tx_traffic_int); - writeq(val64, &bar0->tx_traffic_int); - get_info = ring_data->rx_curr_get_info; get_block = get_info.block_index; put_info = ring_data->rx_curr_put_info; @@ -2312,20 +2301,11 @@ static void rx_intr_handler(ring_info_t *ring_data) static void tx_intr_handler(fifo_info_t *fifo_data) { nic_t *nic = fifo_data->nic; - XENA_dev_config_t __iomem *bar0 = nic->bar0; struct net_device *dev = (struct net_device *) nic->dev; tx_curr_get_info_t get_info, put_info; struct sk_buff *skb; TxD_t *txdlp; u16 j, frg_cnt; - register u64 val64 = 0; - - /* - * tx_traffic_int reg is an R1 register, hence we read and write - * back the same value in the register to clear it - */ - val64 = readq(&bar0->tx_traffic_int); - writeq(val64, &bar0->tx_traffic_int); get_info = fifo_data->tx_curr_get_info; put_info = fifo_data->tx_curr_put_info; @@ -2818,7 +2798,6 @@ int s2io_xmit(struct sk_buff *skb, struct net_device *dev) #endif mac_info_t *mac_control; struct config_param *config; - XENA_dev_config_t __iomem *bar0 = sp->bar0; mac_control = &sp->mac_control; config = &sp->config; @@ -2870,7 +2849,6 @@ int s2io_xmit(struct sk_buff *skb, struct net_device *dev) } txdp->Control_2 |= config->tx_intr_type; - txdp->Control_1 |= (TXD_BUFFER0_SIZE(frg_len) | TXD_GATHER_CODE_FIRST); txdp->Control_1 |= TXD_LIST_OWN_XENA; @@ -2890,6 +2868,8 @@ int s2io_xmit(struct sk_buff *skb, struct net_device *dev) val64 = mac_control->fifos[queue].list_info[put_off].list_phy_addr; writeq(val64, &tx_fifo->TxDL_Pointer); + wmb(); + val64 = (TX_FIFO_LAST_TXD_NUM(frg_cnt) | TX_FIFO_FIRST_LIST | TX_FIFO_LAST_LIST); @@ -2899,9 +2879,6 @@ int s2io_xmit(struct sk_buff *skb, struct net_device *dev) #endif writeq(val64, &tx_fifo->List_Control); - /* Perform a PCI read to flush previous writes */ - val64 = readq(&bar0->general_int_status); - put_off++; put_off %= mac_control->fifos[queue].tx_curr_put_info.fifo_len + 1; mac_control->fifos[queue].tx_curr_put_info.offset = put_off; @@ -2940,7 +2917,7 @@ static irqreturn_t s2io_isr(int irq, void *dev_id, struct pt_regs *regs) nic_t *sp = dev->priv; XENA_dev_config_t __iomem *bar0 = sp->bar0; int i; - u64 reason = 0; + u64 reason = 0, val64; mac_info_t *mac_control; struct config_param *config; @@ -2978,6 +2955,13 @@ static irqreturn_t s2io_isr(int irq, void *dev_id, struct pt_regs *regs) #else /* If Intr is because of Rx Traffic */ if (reason & GEN_INTR_RXTRAFFIC) { + /* + * rx_traffic_int reg is an R1 register, writing all 1's + * will ensure that the actual interrupt causing bit get's + * cleared and hence a read can be avoided. + */ + val64 = 0xFFFFFFFFFFFFFFFFULL; + writeq(val64, &bar0->rx_traffic_int); for (i = 0; i < config->rx_ring_num; i++) { rx_intr_handler(&mac_control->rings[i]); } @@ -2986,6 +2970,14 @@ static irqreturn_t s2io_isr(int irq, void *dev_id, struct pt_regs *regs) /* If Intr is because of Tx Traffic */ if (reason & GEN_INTR_TXTRAFFIC) { + /* + * tx_traffic_int reg is an R1 register, writing all 1's + * will ensure that the actual interrupt causing bit get's + * cleared and hence a read can be avoided. + */ + val64 = 0xFFFFFFFFFFFFFFFFULL; + writeq(val64, &bar0->tx_traffic_int); + for (i = 0; i < config->tx_fifo_num; i++) tx_intr_handler(&mac_control->fifos[i]); } diff --git a/drivers/net/s2io.h b/drivers/net/s2io.h index 69dd0e51dd..ce9bf6d5ee 100644 --- a/drivers/net/s2io.h +++ b/drivers/net/s2io.h @@ -13,6 +13,11 @@ #ifndef _S2IO_H #define _S2IO_H +/* Enable 2 buffer mode by default for SGI system */ +#ifdef CONFIG_IA64_SGI_SN2 +#define CONFIG_2BUFF_MODE +#endif + #define TBD 0 #define BIT(loc) (0x8000000000000000ULL >> (loc)) #define vBIT(val, loc, sz) (((u64)val) << (64-loc-sz))