This is a note to let you know that I've just added the patch titled net: stmmac: reduce unnecessary wakeups from eee sw timer to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-stmmac-reduce-unnecessary-wakeups-from-eee-sw-ti.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b9d40ccf03c4f8e98518e52899faf5722cd68153 Author: Jisheng Zhang <jszhang@xxxxxxxxxx> Date: Sun Jan 23 23:54:58 2022 +0800 net: stmmac: reduce unnecessary wakeups from eee sw timer [ Upstream commit c74ead223deb88bdf18af8c772d7ca5a9b6c3c2b ] Currently, on EEE capable platforms, if EEE SW timer is used, the SW timer cause 1 wakeup/s even if the TX has successfully entered EEE. Remove this unnecessary wakeup by only calling mod_timer() if we haven't successfully entered EEE. Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 161e65333ed94..e6af26b2dcb81 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -400,7 +400,7 @@ static void stmmac_lpi_entry_timer_config(struct stmmac_priv *priv, bool en) * Description: this function is to verify and enter in LPI mode in case of * EEE. */ -static void stmmac_enable_eee_mode(struct stmmac_priv *priv) +static int stmmac_enable_eee_mode(struct stmmac_priv *priv) { u32 tx_cnt = priv->plat->tx_queues_to_use; u32 queue; @@ -410,13 +410,14 @@ static void stmmac_enable_eee_mode(struct stmmac_priv *priv) struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue]; if (tx_q->dirty_tx != tx_q->cur_tx) - return; /* still unfinished work */ + return -EBUSY; /* still unfinished work */ } /* Check and enter in LPI mode */ if (!priv->tx_path_in_lpi_mode) stmmac_set_eee_mode(priv, priv->hw, priv->plat->en_tx_lpi_clockgating); + return 0; } /** @@ -448,8 +449,8 @@ static void stmmac_eee_ctrl_timer(struct timer_list *t) { struct stmmac_priv *priv = from_timer(priv, t, eee_ctrl_timer); - stmmac_enable_eee_mode(priv); - mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(priv->tx_lpi_timer)); + if (stmmac_enable_eee_mode(priv)) + mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(priv->tx_lpi_timer)); } /** @@ -2637,8 +2638,8 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue) if (priv->eee_enabled && !priv->tx_path_in_lpi_mode && priv->eee_sw_timer_en) { - stmmac_enable_eee_mode(priv); - mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(priv->tx_lpi_timer)); + if (stmmac_enable_eee_mode(priv)) + mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(priv->tx_lpi_timer)); } /* We still have pending packets, let's call for a new scheduling */