From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jimmy Perchet Subject: [PATCH RFC 5/5] net:stmmac: asynchronous tx_clean Date: Wed, 16 Oct 2013 17:24:12 +0200 Message-ID: <1381937052-8999-6-git-send-email-jimmy.perchet@parrot.com> References: <1381937052-8999-1-git-send-email-jimmy.perchet@parrot.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , Jimmy Perchet To: Return-path: Received: from co202.xi-lite.net ([149.6.83.202]:60758 "EHLO co202.xi-lite.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760771Ab3JPPja (ORCPT ); Wed, 16 Oct 2013 11:39:30 -0400 In-Reply-To: <1381937052-8999-1-git-send-email-jimmy.perchet@parrot.com> Sender: netdev-owner@vger.kernel.org List-ID: Tx descriptor's cleanup and preparation are serialized, which is not necessary and decrease performance. In addition TX descriptor's cleanup is performed on NET_RX softirq, this is confusing. This patch unserialize tx descriptor's cleanup and preparation and defer cleanup in workqueue. Signed-off-by: Jimmy Perchet --- drivers/net/ethernet/stmicro/stmmac/chain_mode.c | 6 +-- drivers/net/ethernet/stmicro/stmmac/stmmac.h | 6 ++- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 52 +++++++++++++---------- 3 files changed, 37 insertions(+), 27 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c index d6ed0ce..8ab83cb 100644 --- a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c +++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c @@ -120,7 +120,7 @@ static void stmmac_refill_desc3(void *priv_ptr, struct dma_desc *p) * to keep explicit chaining in the descriptor. */ p->des3 = (unsigned int)(priv->dma_rx_phy + - (((priv->dirty_rx) + 1) % + ((priv->dirty_rx + 1) % priv->dma_rx_size) * sizeof(struct dma_desc)); } @@ -135,9 +135,9 @@ static void stmmac_clean_desc3(void *priv_ptr, struct dma_desc *p) * to keep explicit chaining in the descriptor. */ p->des3 = (unsigned int)(priv->dma_tx_phy + - (((priv->dirty_tx + 1) % + ((atomic_read(&priv->dirty_tx) + 1) % priv->dma_tx_size) * - sizeof(struct dma_desc))); + sizeof(struct dma_desc)); } const struct stmmac_chain_mode_ops chain_mode_ops = { diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h index f16a9bd..d5b8906 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h @@ -38,8 +38,8 @@ struct stmmac_priv { struct dma_extended_desc *dma_etx ____cacheline_aligned_in_smp; struct dma_desc *dma_tx; struct sk_buff **tx_skbuff; - unsigned int cur_tx; - unsigned int dirty_tx; + atomic_t cur_tx; + atomic_t dirty_tx; unsigned int dma_tx_size; u32 tx_count_frames; u32 tx_coal_frames; @@ -106,6 +106,8 @@ struct stmmac_priv { u32 adv_ts; int use_riwt; spinlock_t ptp_lock; + struct work_struct txclean_work; + struct workqueue_struct *wq; }; extern int phyaddr; diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 5873246..de614ad 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -48,6 +48,7 @@ #include #endif /* CONFIG_STMMAC_DEBUG_FS */ #include +#include #include "stmmac_ptp.h" #include "stmmac.h" @@ -205,7 +206,8 @@ static void print_pkt(unsigned char *buf, int len) static inline u32 stmmac_tx_avail(struct stmmac_priv *priv) { - return priv->dirty_tx + priv->dma_tx_size - priv->cur_tx - 1; + return atomic_read(&priv->dirty_tx) + priv->dma_tx_size + - atomic_read(&priv->cur_tx) - 1; } /** @@ -230,7 +232,7 @@ static inline void stmmac_hw_fix_mac_speed(struct stmmac_priv *priv) static void stmmac_enable_eee_mode(struct stmmac_priv *priv) { /* Check and enter in LPI mode */ - if ((priv->dirty_tx == priv->cur_tx) && + if ((atomic_read(&priv->dirty_tx) == atomic_read(&priv->cur_tx)) && (priv->tx_path_in_lpi_mode == false)) priv->hw->mac->set_eee_mode(priv->ioaddr); } @@ -1118,8 +1120,8 @@ static int init_dma_desc_rings(struct net_device *dev) priv->tx_skbuff[i] = NULL; } - priv->dirty_tx = 0; - priv->cur_tx = 0; + atomic_set(&priv->dirty_tx, 0); + atomic_set(&priv->cur_tx, 0); stmmac_clear_descriptors(priv); @@ -1264,17 +1266,17 @@ static void stmmac_dma_operation_mode(int mtu, struct stmmac_priv *priv) * @priv: driver private structure * Description: it reclaims resources after transmission completes. */ -static void stmmac_tx_clean(struct stmmac_priv *priv) +static void stmmac_tx_clean(struct work_struct *work) { + struct stmmac_priv *priv = + container_of(work, struct stmmac_priv, txclean_work); unsigned int txsize = priv->dma_tx_size; - spin_lock(&priv->tx_lock); - priv->xstats.tx_clean++; - while (priv->dirty_tx != priv->cur_tx) { + while (atomic_read(&priv->dirty_tx) != atomic_read(&priv->cur_tx)) { int last; - unsigned int entry = priv->dirty_tx % txsize; + unsigned int entry = atomic_read(&priv->dirty_tx) % txsize; struct sk_buff *skb = priv->tx_skbuff[entry]; struct dma_desc *p; @@ -1308,7 +1310,8 @@ static void stmmac_tx_clean(struct stmmac_priv *priv) } if (netif_msg_tx_done(priv)) pr_debug("%s: curr %d, dirty %d\n", __func__, - priv->cur_tx, priv->dirty_tx); + atomic_read(&priv->cur_tx), + atomic_read(&priv->dirty_tx)); if (likely(priv->tx_skbuff_dma[entry])) { dma_unmap_single(priv->device, @@ -1326,7 +1329,8 @@ static void stmmac_tx_clean(struct stmmac_priv *priv) priv->hw->desc->release_tx_desc(p, priv->mode); - priv->dirty_tx++; + wmb(); + atomic_inc(&priv->dirty_tx); } if (unlikely(netif_queue_stopped(priv->dev) && stmmac_tx_avail(priv) > STMMAC_TX_THRESH(priv))) { @@ -1344,7 +1348,6 @@ static void stmmac_tx_clean(struct stmmac_priv *priv) stmmac_enable_eee_mode(priv); mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer)); } - spin_unlock(&priv->tx_lock); } static inline void stmmac_enable_dma_irq(struct stmmac_priv *priv) @@ -1380,8 +1383,8 @@ static void stmmac_tx_err(struct stmmac_priv *priv) priv->hw->desc->init_tx_desc(&priv->dma_tx[i], priv->mode, (i == txsize - 1)); - priv->dirty_tx = 0; - priv->cur_tx = 0; + atomic_set(&priv->dirty_tx, 0); + atomic_set(&priv->cur_tx, 0); priv->hw->dma->start_tx(priv->ioaddr); priv->dev->stats.tx_errors++; @@ -1401,12 +1404,16 @@ static void stmmac_dma_interrupt(struct stmmac_priv *priv) int status; status = priv->hw->dma->dma_interrupt(priv->ioaddr, &priv->xstats); - if (likely((status & handle_rx)) || (status & handle_tx)) { + if (likely(status & handle_rx)) { if (likely(napi_schedule_prep(&priv->napi))) { stmmac_disable_dma_irq(priv); __napi_schedule(&priv->napi); } } + if (likely(status & handle_tx)) + queue_work(priv->wq, &priv->txclean_work); + + if (unlikely(status & tx_hard_error_bump_tc)) { /* Try to bump up the dma threshold on this failure */ if (unlikely(tc != SF_DMA_MODE) && (tc <= 256)) { @@ -1596,8 +1603,7 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv) static void stmmac_tx_timer(unsigned long data) { struct stmmac_priv *priv = (struct stmmac_priv *)data; - - stmmac_tx_clean(priv); + queue_work(priv->wq, &priv->txclean_work); } /** @@ -1876,7 +1882,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) if (priv->tx_path_in_lpi_mode) stmmac_disable_eee_mode(priv); - first_entry = entry = priv->cur_tx % txsize; + first_entry = entry = atomic_read(&priv->cur_tx) % txsize; csum_insertion = (skb->ip_summed == CHECKSUM_PARTIAL); /* To program the descriptors according to the size of the frame */ @@ -1944,12 +1950,13 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) priv->hw->desc->set_tx_owner(first); wmb(); - priv->cur_tx += nb_desc; + atomic_add(nb_desc, &priv->cur_tx); if (netif_msg_pktdata(priv)) { pr_debug("%s: curr %d dirty=%d entry=%d, first=%p, nfrags=%d", - __func__, (priv->cur_tx % txsize), - (priv->dirty_tx % txsize), entry, first, nfrags); + __func__, (atomic_read(&priv->cur_tx) % txsize), + (atomic_read(&priv->dirty_tx) % txsize), entry, + first, nfrags); if (priv->extend_desc) stmmac_display_ring((void *)priv->dma_etx, txsize, 1); @@ -2171,7 +2178,6 @@ static int stmmac_poll(struct napi_struct *napi, int budget) int work_done = 0; priv->xstats.napi_poll++; - stmmac_tx_clean(priv); work_done = stmmac_rx(priv, budget); if (work_done < budget) { @@ -2747,6 +2753,8 @@ struct stmmac_priv *stmmac_dvr_probe(struct device *device, spin_lock_init(&priv->lock); spin_lock_init(&priv->tx_lock); + priv->wq = create_singlethread_workqueue("stmmac_wq"); + INIT_WORK(&priv->txclean_work, stmmac_tx_clean); ret = register_netdev(ndev); if (ret) { -- 1.8.1.2