diff options
| -rw-r--r-- | drivers/net/ethernet/myricom/myri10ge/myri10ge.c | 200 |
1 files changed, 198 insertions, 2 deletions
diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c index 66c040047da7..50a1d4a04eb0 100644 --- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c +++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c @@ -74,6 +74,7 @@ #ifdef CONFIG_MTRR #include <asm/mtrr.h> #endif +#include <net/busy_poll.h> #include "myri10ge_mcp.h" #include "myri10ge_mcp_gen_header.h" @@ -194,6 +195,21 @@ struct myri10ge_slice_state { int cpu; __be32 __iomem *dca_tag; #endif +#ifdef CONFIG_NET_RX_BUSY_POLL + unsigned int state; +#define SLICE_STATE_IDLE 0 +#define SLICE_STATE_NAPI 1 /* NAPI owns this slice */ +#define SLICE_STATE_POLL 2 /* poll owns this slice */ +#define SLICE_LOCKED (SLICE_STATE_NAPI | SLICE_STATE_POLL) +#define SLICE_STATE_NAPI_YIELD 4 /* NAPI yielded this slice */ +#define SLICE_STATE_POLL_YIELD 8 /* poll yielded this slice */ +#define SLICE_USER_PEND (SLICE_STATE_POLL | SLICE_STATE_POLL_YIELD) + spinlock_t lock; + unsigned long lock_napi_yield; + unsigned long lock_poll_yield; + unsigned long busy_poll_miss; + unsigned long busy_poll_cnt; +#endif /* CONFIG_NET_RX_BUSY_POLL */ char irq_desc[32]; }; @@ -909,6 +925,92 @@ abort: return status; } +#ifdef CONFIG_NET_RX_BUSY_POLL +static inline void myri10ge_ss_init_lock(struct myri10ge_slice_state *ss) +{ + spin_lock_init(&ss->lock); + ss->state = SLICE_STATE_IDLE; +} + +static inline bool myri10ge_ss_lock_napi(struct myri10ge_slice_state *ss) +{ + int rc = true; + spin_lock(&ss->lock); + if ((ss->state & SLICE_LOCKED)) { + WARN_ON((ss->state & SLICE_STATE_NAPI)); + ss->state |= SLICE_STATE_NAPI_YIELD; + rc = false; + ss->lock_napi_yield++; + } else + ss->state = SLICE_STATE_NAPI; + spin_unlock(&ss->lock); + return rc; +} + +static inline void myri10ge_ss_unlock_napi(struct myri10ge_slice_state *ss) +{ + spin_lock(&ss->lock); + WARN_ON((ss->state & (SLICE_STATE_POLL | SLICE_STATE_NAPI_YIELD))); + ss->state = SLICE_STATE_IDLE; + spin_unlock(&ss->lock); +} + +static inline bool myri10ge_ss_lock_poll(struct myri10ge_slice_state *ss) +{ + int rc = true; + spin_lock_bh(&ss->lock); + if ((ss->state & SLICE_LOCKED)) { + ss->state |= SLICE_STATE_POLL_YIELD; + rc = false; + ss->lock_poll_yield++; + } else + ss->state |= SLICE_STATE_POLL; + spin_unlock_bh(&ss->lock); + return rc; +} + +static inline void myri10ge_ss_unlock_poll(struct myri10ge_slice_state *ss) +{ + spin_lock_bh(&ss->lock); + WARN_ON((ss->state & SLICE_STATE_NAPI)); + ss->state = SLICE_STATE_IDLE; + spin_unlock_bh(&ss->lock); +} + +static inline bool myri10ge_ss_busy_polling(struct myri10ge_slice_state *ss) +{ + WARN_ON(!(ss->state & SLICE_LOCKED)); + return (ss->state & SLICE_USER_PEND); +} +#else /* CONFIG_NET_RX_BUSY_POLL */ +static inline void myri10ge_ss_init_lock(struct myri10ge_slice_state *ss) +{ +} + +static inline bool myri10ge_ss_lock_napi(struct myri10ge_slice_state *ss) +{ + return false; +} + +static inline void myri10ge_ss_unlock_napi(struct myri10ge_slice_state *ss) +{ +} + +static inline bool myri10ge_ss_lock_poll(struct myri10ge_slice_state *ss) +{ + return false; +} + +static inline void myri10ge_ss_unlock_poll(struct myri10ge_slice_state *ss) +{ +} + +static inline bool myri10ge_ss_busy_polling(struct myri10ge_slice_state *ss) +{ + return false; +} +#endif + static int myri10ge_reset(struct myri10ge_priv *mgp) { struct myri10ge_cmd cmd; @@ -1300,6 +1402,8 @@ myri10ge_vlan_rx(struct net_device *dev, void *addr, struct sk_buff *skb) } } +#define MYRI10GE_HLEN 64 /* Bytes to copy from page to skb linear memory */ + static inline int myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum) { @@ -1311,6 +1415,7 @@ myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum) struct pci_dev *pdev = mgp->pdev; struct net_device *dev = mgp->dev; u8 *va; + bool polling; if (len <= mgp->small_bytes) { rx = &ss->rx_small; @@ -1325,7 +1430,15 @@ myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum) va = page_address(rx->info[idx].page) + rx->info[idx].page_offset; prefetch(va); - skb = napi_get_frags(&ss->napi); + /* When busy polling in user context, allocate skb and copy headers to + * skb's linear memory ourselves. When not busy polling, use the napi + * gro api. + */ + polling = myri10ge_ss_busy_polling(ss); + if (polling) + skb = netdev_alloc_skb(dev, MYRI10GE_HLEN + 16); + else + skb = napi_get_frags(&ss->napi); if (unlikely(skb == NULL)) { ss->stats.rx_dropped++; for (i = 0, remainder = len; remainder > 0; i++) { @@ -1364,8 +1477,29 @@ myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum) } myri10ge_vlan_rx(mgp->dev, va, skb); skb_record_rx_queue(skb, ss - &mgp->ss[0]); + skb_mark_napi_id(skb, &ss->napi); + + if (polling) { + int hlen; + + /* myri10ge_vlan_rx might have moved the header, so compute + * length and address again. + */ + hlen = MYRI10GE_HLEN > skb->len ? skb->len : MYRI10GE_HLEN; + va = page_address(skb_frag_page(&rx_frags[0])) + + rx_frags[0].page_offset; + /* Copy header into the skb linear memory */ + skb_copy_to_linear_data(skb, va, hlen); + rx_frags[0].page_offset += hlen; + rx_frags[0].size -= hlen; + skb->data_len -= hlen; + skb->tail += hlen; + skb->protocol = eth_type_trans(skb, dev); + netif_receive_skb(skb); + } + else + napi_gro_frags(&ss->napi); - napi_gro_frags(&ss->napi); return 1; } @@ -1524,10 +1658,14 @@ static int myri10ge_poll(struct napi_struct *napi, int budget) if (ss->mgp->dca_enabled) myri10ge_update_dca(ss); #endif + /* Try later if the busy_poll handler is running. */ + if (!myri10ge_ss_lock_napi(ss)) + return budget; /* process as many rx events as NAPI will allow */ work_done = myri10ge_clean_rx_done(ss, budget); + myri10ge_ss_unlock_napi(ss); if (work_done < budget) { napi_complete(napi); put_be32(htonl(3), ss->irq_claim); @@ -1535,6 +1673,34 @@ static int myri10ge_poll(struct napi_struct *napi, int budget) return work_done; } +#ifdef CONFIG_NET_RX_BUSY_POLL +static int myri10ge_busy_poll(struct napi_struct *napi) +{ + struct myri10ge_slice_state *ss = + container_of(napi, struct myri10ge_slice_state, napi); + struct myri10ge_priv *mgp = ss->mgp; + int work_done; + + /* Poll only when the link is up */ + if (mgp->link_state != MXGEFW_LINK_UP) + return LL_FLUSH_FAILED; + + if (!myri10ge_ss_lock_poll(ss)) + return LL_FLUSH_BUSY; + + /* Process a small number of packets */ + work_done = myri10ge_clean_rx_done(ss, 4); + if (work_done) + ss->busy_poll_cnt += work_done; + else + ss->busy_poll_miss++; + + myri10ge_ss_unlock_poll(ss); + + return work_done; +} +#endif /* CONFIG_NET_RX_BUSY_POLL */ + static irqreturn_t myri10ge_intr(int irq, void *arg) { struct myri10ge_slice_state *ss = arg; @@ -1742,6 +1908,10 @@ static const char myri10ge_gstrings_slice_stats[][ETH_GSTRING_LEN] = { "tx_pkt_start", "tx_pkt_done", "tx_req", "tx_done", "rx_small_cnt", "rx_big_cnt", "wake_queue", "stop_queue", "tx_linearized", +#ifdef CONFIG_NET_RX_BUSY_POLL + "rx_lock_napi_yield", "rx_lock_poll_yield", "rx_busy_poll_miss", + "rx_busy_poll_cnt", +#endif }; #define MYRI10GE_NET_STATS_LEN 21 @@ -1842,6 +2012,12 @@ myri10ge_get_ethtool_stats(struct net_device *netdev, data[i++] = (unsigned int)ss->tx.wake_queue; data[i++] = (unsigned int)ss->tx.stop_queue; data[i++] = (unsigned int)ss->tx.linearized; +#ifdef CONFIG_NET_RX_BUSY_POLL + data[i++] = ss->lock_napi_yield; + data[i++] = ss->lock_poll_yield; + data[i++] = ss->busy_poll_miss; + data[i++] = ss->busy_poll_cnt; +#endif } } @@ -2405,6 +2581,9 @@ static int myri10ge_open(struct net_device *dev) goto abort_with_rings; } + /* Initialize the slice spinlock and state used for polling */ + myri10ge_ss_init_lock(ss); + /* must happen prior to any irq */ napi_enable(&(ss)->napi); } @@ -2481,9 +2660,19 @@ static int myri10ge_close(struct net_device *dev) del_timer_sync(&mgp->watchdog_timer); mgp->running = MYRI10GE_ETH_STOPPING; + local_bh_disable(); /* myri10ge_ss_lock_napi needs bh disabled */ for (i = 0; i < mgp->num_slices; i++) { napi_disable(&mgp->ss[i].napi); + /* Lock the slice to prevent the busy_poll handler from + * accessing it. Later when we bring the NIC up, myri10ge_open + * resets the slice including this lock. + */ + while (!myri10ge_ss_lock_napi(&mgp->ss[i])) { + pr_info("Slice %d locked\n", i); + mdelay(1); + } } + local_bh_enable(); netif_carrier_off(dev); netif_tx_stop_all_queues(dev); @@ -3569,8 +3758,11 @@ static void myri10ge_free_slices(struct myri10ge_priv *mgp) ss->fw_stats, ss->fw_stats_bus); ss->fw_stats = NULL; } + napi_hash_del(&ss->napi); netif_napi_del(&ss->napi); } + /* Wait till napi structs are no longer used, and then free ss. */ + synchronize_rcu(); kfree(mgp->ss); mgp->ss = NULL; } @@ -3606,6 +3798,7 @@ static int myri10ge_alloc_slices(struct myri10ge_priv *mgp) ss->dev = mgp->dev; netif_napi_add(ss->dev, &ss->napi, myri10ge_poll, myri10ge_napi_weight); + napi_hash_add(&ss->napi); } return 0; abort: @@ -3748,6 +3941,9 @@ static const struct net_device_ops myri10ge_netdev_ops = { .ndo_change_mtu = myri10ge_change_mtu, .ndo_set_rx_mode = myri10ge_set_multicast_list, .ndo_set_mac_address = myri10ge_set_mac_address, +#ifdef CONFIG_NET_RX_BUSY_POLL + .ndo_busy_poll = myri10ge_busy_poll, +#endif }; static int myri10ge_probe(struct pci_dev *pdev, const struct pci_device_id *ent) |
