From c9e8c93b9d09a9a8322a894f3167d2d498acc69a Mon Sep 17 00:00:00 2001 From: Jack Vogel Date: Thu, 27 Jul 2017 11:44:14 -0700 Subject: [PATCH] Revert "ixgbevf: get rid of custom busy polling code" This reverts commit 1975e69c708706b84d9462ce7c0135d33310c28a. Performance regression, because the net/core napi support is not present. Orabug: 26494997 Signed-off-by: Jack Vogel Reviewed-by: Shannon Nelson --- drivers/net/ethernet/intel/ixgbevf/ethtool.c | 38 ++++++ drivers/net/ethernet/intel/ixgbevf/ixgbevf.h | 113 ++++++++++++++++++ .../net/ethernet/intel/ixgbevf/ixgbevf_main.c | 64 ++++++++++ 3 files changed, 215 insertions(+) diff --git a/drivers/net/ethernet/intel/ixgbevf/ethtool.c b/drivers/net/ethernet/intel/ixgbevf/ethtool.c index 08fa3030276ed..2c8d9c0988205 100644 --- a/drivers/net/ethernet/intel/ixgbevf/ethtool.c +++ b/drivers/net/ethernet/intel/ixgbevf/ethtool.c @@ -432,6 +432,11 @@ static void ixgbevf_get_ethtool_stats(struct net_device *netdev, if (!ring) { data[i++] = 0; data[i++] = 0; +#ifdef BP_EXTENDED_STATS + data[i++] = 0; + data[i++] = 0; + data[i++] = 0; +#endif continue; } @@ -441,6 +446,12 @@ static void ixgbevf_get_ethtool_stats(struct net_device *netdev, data[i + 1] = ring->stats.bytes; } while (u64_stats_fetch_retry_irq(&ring->syncp, start)); i += 2; +#ifdef BP_EXTENDED_STATS + data[i] = ring->stats.yields; + data[i + 1] = ring->stats.misses; + data[i + 2] = ring->stats.cleaned; + i += 3; +#endif } /* populate Rx queue data */ @@ -449,6 +460,11 @@ static void ixgbevf_get_ethtool_stats(struct net_device *netdev, if (!ring) { data[i++] = 0; data[i++] = 0; +#ifdef BP_EXTENDED_STATS + data[i++] = 0; + data[i++] = 0; + data[i++] = 0; +#endif continue; } @@ -458,6 +474,12 @@ static void ixgbevf_get_ethtool_stats(struct net_device *netdev, data[i + 1] = ring->stats.bytes; } while (u64_stats_fetch_retry_irq(&ring->syncp, start)); i += 2; +#ifdef BP_EXTENDED_STATS + data[i] = ring->stats.yields; + data[i + 1] = ring->stats.misses; + data[i + 2] = ring->stats.cleaned; + i += 3; +#endif } } @@ -485,12 +507,28 @@ static void ixgbevf_get_strings(struct net_device *netdev, u32 stringset, p += ETH_GSTRING_LEN; sprintf(p, "tx_queue_%u_bytes", i); p += ETH_GSTRING_LEN; +#ifdef BP_EXTENDED_STATS + sprintf(p, "tx_queue_%u_bp_napi_yield", i); + p += ETH_GSTRING_LEN; + sprintf(p, "tx_queue_%u_bp_misses", i); + p += ETH_GSTRING_LEN; + sprintf(p, "tx_queue_%u_bp_cleaned", i); + p += ETH_GSTRING_LEN; +#endif /* BP_EXTENDED_STATS */ } for (i = 0; i < adapter->num_rx_queues; i++) { sprintf(p, "rx_queue_%u_packets", i); p += ETH_GSTRING_LEN; sprintf(p, "rx_queue_%u_bytes", i); p += ETH_GSTRING_LEN; +#ifdef BP_EXTENDED_STATS + sprintf(p, "rx_queue_%u_bp_poll_yield", i); + p += ETH_GSTRING_LEN; + sprintf(p, "rx_queue_%u_bp_misses", i); + p += ETH_GSTRING_LEN; + sprintf(p, "rx_queue_%u_bp_cleaned", i); + p += ETH_GSTRING_LEN; +#endif /* BP_EXTENDED_STATS */ } break; } diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h b/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h index 581f44bbd7b3b..9ac851d56e93d 100644 --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h @@ -37,6 +37,11 @@ #include "vf.h" +#ifdef CONFIG_NET_RX_BUSY_POLL +#include +#define BP_EXTENDED_STATS +#endif + #define IXGBE_MAX_TXD_PWR 14 #define IXGBE_MAX_DATA_PER_TXD BIT(IXGBE_MAX_TXD_PWR) @@ -68,6 +73,11 @@ struct ixgbevf_rx_buffer { struct ixgbevf_stats { u64 packets; u64 bytes; +#ifdef BP_EXTENDED_STATS + u64 yields; + u64 misses; + u64 cleaned; +#endif }; struct ixgbevf_tx_queue_stats { @@ -207,6 +217,109 @@ struct ixgbevf_q_vector { #endif /* CONFIG_NET_RX_BUSY_POLL */ }; +#ifdef CONFIG_NET_RX_BUSY_POLL +static inline void ixgbevf_qv_init_lock(struct ixgbevf_q_vector *q_vector) +{ + spin_lock_init(&q_vector->lock); + q_vector->state = IXGBEVF_QV_STATE_IDLE; +} + +/* called from the device poll routine to get ownership of a q_vector */ +static inline bool ixgbevf_qv_lock_napi(struct ixgbevf_q_vector *q_vector) +{ + int rc = true; + + spin_lock_bh(&q_vector->lock); + if (q_vector->state & IXGBEVF_QV_LOCKED) { + WARN_ON(q_vector->state & IXGBEVF_QV_STATE_NAPI); + q_vector->state |= IXGBEVF_QV_STATE_NAPI_YIELD; + rc = false; +#ifdef BP_EXTENDED_STATS + q_vector->tx.ring->stats.yields++; +#endif + } else { + /* we don't care if someone yielded */ + q_vector->state = IXGBEVF_QV_STATE_NAPI; + } + spin_unlock_bh(&q_vector->lock); + return rc; +} + +/* returns true is someone tried to get the qv while napi had it */ +static inline bool ixgbevf_qv_unlock_napi(struct ixgbevf_q_vector *q_vector) +{ + int rc = false; + + spin_lock_bh(&q_vector->lock); + WARN_ON(q_vector->state & (IXGBEVF_QV_STATE_POLL | + IXGBEVF_QV_STATE_NAPI_YIELD)); + + if (q_vector->state & IXGBEVF_QV_STATE_POLL_YIELD) + rc = true; + /* reset state to idle, unless QV is disabled */ + q_vector->state &= IXGBEVF_QV_STATE_DISABLED; + spin_unlock_bh(&q_vector->lock); + return rc; +} + +/* called from ixgbevf_low_latency_poll() */ +static inline bool ixgbevf_qv_lock_poll(struct ixgbevf_q_vector *q_vector) +{ + int rc = true; + + spin_lock_bh(&q_vector->lock); + if ((q_vector->state & IXGBEVF_QV_LOCKED)) { + q_vector->state |= IXGBEVF_QV_STATE_POLL_YIELD; + rc = false; +#ifdef BP_EXTENDED_STATS + q_vector->rx.ring->stats.yields++; +#endif + } else { + /* preserve yield marks */ + q_vector->state |= IXGBEVF_QV_STATE_POLL; + } + spin_unlock_bh(&q_vector->lock); + return rc; +} + +/* returns true if someone tried to get the qv while it was locked */ +static inline bool ixgbevf_qv_unlock_poll(struct ixgbevf_q_vector *q_vector) +{ + int rc = false; + + spin_lock_bh(&q_vector->lock); + WARN_ON(q_vector->state & (IXGBEVF_QV_STATE_NAPI)); + + if (q_vector->state & IXGBEVF_QV_STATE_POLL_YIELD) + rc = true; + /* reset state to idle, unless QV is disabled */ + q_vector->state &= IXGBEVF_QV_STATE_DISABLED; + spin_unlock_bh(&q_vector->lock); + return rc; +} + +/* true if a socket is polling, even if it did not get the lock */ +static inline bool ixgbevf_qv_busy_polling(struct ixgbevf_q_vector *q_vector) +{ + WARN_ON(!(q_vector->state & IXGBEVF_QV_OWNED)); + return q_vector->state & IXGBEVF_QV_USER_PEND; +} + +/* false if QV is currently owned */ +static inline bool ixgbevf_qv_disable(struct ixgbevf_q_vector *q_vector) +{ + int rc = true; + + spin_lock_bh(&q_vector->lock); + if (q_vector->state & IXGBEVF_QV_OWNED) + rc = false; + q_vector->state |= IXGBEVF_QV_STATE_DISABLED; + spin_unlock_bh(&q_vector->lock); + return rc; +} + +#endif /* CONFIG_NET_RX_BUSY_POLL */ + /* microsecond values for various ITR rates shifted by 2 to fit itr register * with the first 3 bits reserved 0 */ diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c index 9c81c52790ebd..db919958ecce9 100644 --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c @@ -456,6 +456,16 @@ static bool ixgbevf_clean_tx_irq(struct ixgbevf_q_vector *q_vector, static void ixgbevf_rx_skb(struct ixgbevf_q_vector *q_vector, struct sk_buff *skb) { +#ifdef CONFIG_NET_RX_BUSY_POLL + skb_mark_napi_id(skb, &q_vector->napi); + + if (ixgbevf_qv_busy_polling(q_vector)) { + netif_receive_skb(skb); + /* exit early if we busy polled */ + return; + } +#endif /* CONFIG_NET_RX_BUSY_POLL */ + napi_gro_receive(&q_vector->napi, skb); } @@ -1018,6 +1028,10 @@ static int ixgbevf_poll(struct napi_struct *napi, int budget) if (budget <= 0) return budget; +#ifdef CONFIG_NET_RX_BUSY_POLL + if (!ixgbevf_qv_lock_napi(q_vector)) + return budget; +#endif /* attempt to distribute budget to each queue fairly, but don't allow * the budget to go below 1 because we'll exit polling @@ -1034,6 +1048,10 @@ static int ixgbevf_poll(struct napi_struct *napi, int budget) clean_complete &= (cleaned < per_ring_budget); } +#ifdef CONFIG_NET_RX_BUSY_POLL + ixgbevf_qv_unlock_napi(q_vector); +#endif + /* If all work not completed, return budget and keep polling */ if (!clean_complete) return budget; @@ -1068,6 +1086,40 @@ void ixgbevf_write_eitr(struct ixgbevf_q_vector *q_vector) IXGBE_WRITE_REG(hw, IXGBE_VTEITR(v_idx), itr_reg); } +#ifdef CONFIG_NET_RX_BUSY_POLL +/* must be called with local_bh_disable()d */ +static int ixgbevf_busy_poll_recv(struct napi_struct *napi) +{ + struct ixgbevf_q_vector *q_vector = + container_of(napi, struct ixgbevf_q_vector, napi); + struct ixgbevf_adapter *adapter = q_vector->adapter; + struct ixgbevf_ring *ring; + int found = 0; + + if (test_bit(__IXGBEVF_DOWN, &adapter->state)) + return LL_FLUSH_FAILED; + + if (!ixgbevf_qv_lock_poll(q_vector)) + return LL_FLUSH_BUSY; + + ixgbevf_for_each_ring(ring, q_vector->rx) { + found = ixgbevf_clean_rx_irq(q_vector, ring, 4); +#ifdef BP_EXTENDED_STATS + if (found) + ring->stats.cleaned += found; + else + ring->stats.misses++; +#endif + if (found) + break; + } + + ixgbevf_qv_unlock_poll(q_vector); + + return found; +} +#endif /* CONFIG_NET_RX_BUSY_POLL */ + /** * ixgbevf_configure_msix - Configure MSI-X hardware * @adapter: board private structure @@ -1925,6 +1977,9 @@ static void ixgbevf_napi_enable_all(struct ixgbevf_adapter *adapter) for (q_idx = 0; q_idx < q_vectors; q_idx++) { q_vector = adapter->q_vector[q_idx]; +#ifdef CONFIG_NET_RX_BUSY_POLL + ixgbevf_qv_init_lock(adapter->q_vector[q_idx]); +#endif napi_enable(&q_vector->napi); } } @@ -1938,6 +1993,12 @@ static void ixgbevf_napi_disable_all(struct ixgbevf_adapter *adapter) for (q_idx = 0; q_idx < q_vectors; q_idx++) { q_vector = adapter->q_vector[q_idx]; napi_disable(&q_vector->napi); +#ifdef CONFIG_NET_RX_BUSY_POLL + while (!ixgbevf_qv_disable(adapter->q_vector[q_idx])) { + pr_info("QV %d locked\n", q_idx); + usleep_range(1000, 20000); + } +#endif /* CONFIG_NET_RX_BUSY_POLL */ } } @@ -3931,6 +3992,9 @@ static const struct net_device_ops ixgbevf_netdev_ops = { .ndo_tx_timeout = ixgbevf_tx_timeout, .ndo_vlan_rx_add_vid = ixgbevf_vlan_rx_add_vid, .ndo_vlan_rx_kill_vid = ixgbevf_vlan_rx_kill_vid, +#ifdef CONFIG_NET_RX_BUSY_POLL + .ndo_busy_poll = ixgbevf_busy_poll_recv, +#endif #ifdef CONFIG_NET_POLL_CONTROLLER .ndo_poll_controller = ixgbevf_netpoll, #endif -- 2.50.1