netdev - [PATCH net-next] r8169: improve handling task scheduling

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Date: Mon, 27 Nov 2023 18:20:11 +0100
From: Heiner Kallweit <hkallweit1@...il.com>
To: Realtek linux nic maintainers <nic_swsd@...ltek.com>,
 Paolo Abeni <pabeni@...hat.com>, David Miller <davem@...emloft.net>,
 Jakub Kicinski <kuba@...nel.org>, Eric Dumazet <edumazet@...gle.com>
Cc: "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: [PATCH net-next] r8169: improve handling task scheduling

If we know that the task is going to be a no-op, don't even schedule it.
And remove the check for netif_running() in the worker function, the
check for flag RTL_FLAG_TASK_ENABLED is sufficient. Note that we can't
remove the check for flag RTL_FLAG_TASK_ENABLED in the worker function
because we have no guarantee when it will be executed.

Signed-off-by: Heiner Kallweit <hkallweit1@...il.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index b74d7cc50..91d9dc5a7 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -2228,6 +2228,9 @@ u16 rtl8168h_2_get_adc_bias_ioffset(struct rtl8169_private *tp)
 
 static void rtl_schedule_task(struct rtl8169_private *tp, enum rtl_flag flag)
 {
+	if (!test_bit(RTL_FLAG_TASK_ENABLED, tp->wk.flags))
+		return;
+
 	set_bit(flag, tp->wk.flags);
 	schedule_work(&tp->wk.work);
 }
@@ -4468,8 +4471,7 @@ static void rtl_task(struct work_struct *work)
 
 	rtnl_lock();
 
-	if (!netif_running(tp->dev) ||
-	    !test_bit(RTL_FLAG_TASK_ENABLED, tp->wk.flags))
+	if (!test_bit(RTL_FLAG_TASK_ENABLED, tp->wk.flags))
 		goto out_unlock;
 
 	if (test_and_clear_bit(RTL_FLAG_TASK_TX_TIMEOUT, tp->wk.flags)) {
-- 
2.43.0