+++ /dev/null
-From fabec3dc2234d5cdd8c87178c0ef8c6490165b77 Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Tue, 19 Feb 2019 10:38:47 +0100
-Subject: net: stmmac: Fix NAPI poll in TX path when in multi-queue
-
-From: Jose Abreu <jose.abreu@synopsys.com>
-
-[ Upstream commit 4ccb45857c2c0776d0f72e39768295062c1a0de1 ]
-
-Commit 8fce33317023 introduced the concept of NAPI per-channel and
-independent cleaning of TX path.
-
-This is currently breaking performance in some cases. The scenario
-happens when all packets are being received in Queue 0 but the TX is
-performed in Queue != 0.
-
-Fix this by using different NAPI instances per each TX and RX queue, as
-suggested by Florian.
-
-Changes from v2:
- - Only force restart transmission if there are pending packets
-Changes from v1:
- - Pass entire ring size to TX clean path (Florian)
-
-Signed-off-by: Jose Abreu <joabreu@synopsys.com>
-Cc: Florian Fainelli <f.fainelli@gmail.com>
-Cc: Joao Pinto <jpinto@synopsys.com>
-Cc: David S. Miller <davem@davemloft.net>
-Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
-Cc: Alexandre Torgue <alexandre.torgue@st.com>
-Signed-off-by: David S. Miller <davem@davemloft.net>
-Signed-off-by: Sasha Levin <sashal@kernel.org>
----
- drivers/net/ethernet/stmicro/stmmac/stmmac.h | 5 +-
- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 115 ++++++++++--------
- 2 files changed, 68 insertions(+), 52 deletions(-)
-
-diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
-index 63e1064b27a24..e697ecd9b0a64 100644
---- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
-+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
-@@ -78,11 +78,10 @@ struct stmmac_rx_queue {
- };
-
- struct stmmac_channel {
-- struct napi_struct napi ____cacheline_aligned_in_smp;
-+ struct napi_struct rx_napi ____cacheline_aligned_in_smp;
-+ struct napi_struct tx_napi ____cacheline_aligned_in_smp;
- struct stmmac_priv *priv_data;
- u32 index;
-- int has_rx;
-- int has_tx;
- };
-
- struct stmmac_tc_entry {
-diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
-index 014fe93ed2d82..f4542ac0852d2 100644
---- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
-+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
-@@ -155,7 +155,10 @@ static void stmmac_disable_all_queues(struct stmmac_priv *priv)
- for (queue = 0; queue < maxq; queue++) {
- struct stmmac_channel *ch = &priv->channel[queue];
-
-- napi_disable(&ch->napi);
-+ if (queue < rx_queues_cnt)
-+ napi_disable(&ch->rx_napi);
-+ if (queue < tx_queues_cnt)
-+ napi_disable(&ch->tx_napi);
- }
- }
-
-@@ -173,7 +176,10 @@ static void stmmac_enable_all_queues(struct stmmac_priv *priv)
- for (queue = 0; queue < maxq; queue++) {
- struct stmmac_channel *ch = &priv->channel[queue];
-
-- napi_enable(&ch->napi);
-+ if (queue < rx_queues_cnt)
-+ napi_enable(&ch->rx_napi);
-+ if (queue < tx_queues_cnt)
-+ napi_enable(&ch->tx_napi);
- }
- }
-
-@@ -1946,6 +1952,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue)
- mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer));
- }
-
-+ /* We still have pending packets, let's call for a new scheduling */
-+ if (tx_q->dirty_tx != tx_q->cur_tx)
-+ mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(10));
-+
- __netif_tx_unlock_bh(netdev_get_tx_queue(priv->dev, queue));
-
- return count;
-@@ -2036,23 +2046,15 @@ static int stmmac_napi_check(struct stmmac_priv *priv, u32 chan)
- int status = stmmac_dma_interrupt_status(priv, priv->ioaddr,
- &priv->xstats, chan);
- struct stmmac_channel *ch = &priv->channel[chan];
-- bool needs_work = false;
--
-- if ((status & handle_rx) && ch->has_rx) {
-- needs_work = true;
-- } else {
-- status &= ~handle_rx;
-- }
-
-- if ((status & handle_tx) && ch->has_tx) {
-- needs_work = true;
-- } else {
-- status &= ~handle_tx;
-+ if ((status & handle_rx) && (chan < priv->plat->rx_queues_to_use)) {
-+ stmmac_disable_dma_irq(priv, priv->ioaddr, chan);
-+ napi_schedule_irqoff(&ch->rx_napi);
- }
-
-- if (needs_work && napi_schedule_prep(&ch->napi)) {
-+ if ((status & handle_tx) && (chan < priv->plat->tx_queues_to_use)) {
- stmmac_disable_dma_irq(priv, priv->ioaddr, chan);
-- __napi_schedule(&ch->napi);
-+ napi_schedule_irqoff(&ch->tx_napi);
- }
-
- return status;
-@@ -2248,8 +2250,14 @@ static void stmmac_tx_timer(struct timer_list *t)
-
- ch = &priv->channel[tx_q->queue_index];
-
-- if (likely(napi_schedule_prep(&ch->napi)))
-- __napi_schedule(&ch->napi);
-+ /*
-+ * If NAPI is already running we can miss some events. Let's rearm
-+ * the timer and try again.
-+ */
-+ if (likely(napi_schedule_prep(&ch->tx_napi)))
-+ __napi_schedule(&ch->tx_napi);
-+ else
-+ mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(10));
- }
-
- /**
-@@ -3506,7 +3514,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
- else
- skb->ip_summed = CHECKSUM_UNNECESSARY;
-
-- napi_gro_receive(&ch->napi, skb);
-+ napi_gro_receive(&ch->rx_napi, skb);
-
- priv->dev->stats.rx_packets++;
- priv->dev->stats.rx_bytes += frame_len;
-@@ -3520,40 +3528,45 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
- return count;
- }
-
--/**
-- * stmmac_poll - stmmac poll method (NAPI)
-- * @napi : pointer to the napi structure.
-- * @budget : maximum number of packets that the current CPU can receive from
-- * all interfaces.
-- * Description :
-- * To look at the incoming frames and clear the tx resources.
-- */
--static int stmmac_napi_poll(struct napi_struct *napi, int budget)
-+static int stmmac_napi_poll_rx(struct napi_struct *napi, int budget)
- {
- struct stmmac_channel *ch =
-- container_of(napi, struct stmmac_channel, napi);
-+ container_of(napi, struct stmmac_channel, rx_napi);
- struct stmmac_priv *priv = ch->priv_data;
-- int work_done, rx_done = 0, tx_done = 0;
- u32 chan = ch->index;
-+ int work_done;
-
- priv->xstats.napi_poll++;
-
-- if (ch->has_tx)
-- tx_done = stmmac_tx_clean(priv, budget, chan);
-- if (ch->has_rx)
-- rx_done = stmmac_rx(priv, budget, chan);
-+ work_done = stmmac_rx(priv, budget, chan);
-+ if (work_done < budget && napi_complete_done(napi, work_done))
-+ stmmac_enable_dma_irq(priv, priv->ioaddr, chan);
-+ return work_done;
-+}
-
-- work_done = max(rx_done, tx_done);
-- work_done = min(work_done, budget);
-+static int stmmac_napi_poll_tx(struct napi_struct *napi, int budget)
-+{
-+ struct stmmac_channel *ch =
-+ container_of(napi, struct stmmac_channel, tx_napi);
-+ struct stmmac_priv *priv = ch->priv_data;
-+ struct stmmac_tx_queue *tx_q;
-+ u32 chan = ch->index;
-+ int work_done;
-
-- if (work_done < budget && napi_complete_done(napi, work_done)) {
-- int stat;
-+ priv->xstats.napi_poll++;
-+
-+ work_done = stmmac_tx_clean(priv, DMA_TX_SIZE, chan);
-+ work_done = min(work_done, budget);
-
-+ if (work_done < budget && napi_complete_done(napi, work_done))
- stmmac_enable_dma_irq(priv, priv->ioaddr, chan);
-- stat = stmmac_dma_interrupt_status(priv, priv->ioaddr,
-- &priv->xstats, chan);
-- if (stat && napi_reschedule(napi))
-- stmmac_disable_dma_irq(priv, priv->ioaddr, chan);
-+
-+ /* Force transmission restart */
-+ tx_q = &priv->tx_queue[chan];
-+ if (tx_q->cur_tx != tx_q->dirty_tx) {
-+ stmmac_enable_dma_transmission(priv, priv->ioaddr);
-+ stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr,
-+ chan);
- }
-
- return work_done;
-@@ -4376,13 +4389,14 @@ int stmmac_dvr_probe(struct device *device,
- ch->priv_data = priv;
- ch->index = queue;
-
-- if (queue < priv->plat->rx_queues_to_use)
-- ch->has_rx = true;
-- if (queue < priv->plat->tx_queues_to_use)
-- ch->has_tx = true;
--
-- netif_napi_add(ndev, &ch->napi, stmmac_napi_poll,
-- NAPI_POLL_WEIGHT);
-+ if (queue < priv->plat->rx_queues_to_use) {
-+ netif_napi_add(ndev, &ch->rx_napi, stmmac_napi_poll_rx,
-+ NAPI_POLL_WEIGHT);
-+ }
-+ if (queue < priv->plat->tx_queues_to_use) {
-+ netif_napi_add(ndev, &ch->tx_napi, stmmac_napi_poll_tx,
-+ NAPI_POLL_WEIGHT);
-+ }
- }
-
- mutex_init(&priv->lock);
-@@ -4438,7 +4452,10 @@ error_mdio_register:
- for (queue = 0; queue < maxq; queue++) {
- struct stmmac_channel *ch = &priv->channel[queue];
-
-- netif_napi_del(&ch->napi);
-+ if (queue < priv->plat->rx_queues_to_use)
-+ netif_napi_del(&ch->rx_napi);
-+ if (queue < priv->plat->tx_queues_to_use)
-+ netif_napi_del(&ch->tx_napi);
- }
- error_hw_init:
- destroy_workqueue(priv->wq);
---
-2.20.1
-
projects / thirdparty / kernel / stable-queue.git / commitdiff
