netdev - [PATCH net-next] r8169: don't try to disable interrupts if NAPI is scheduled already

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Message-ID: <78c7f2fb-9772-1015-8c1d-632cbdff253f@gmail.com>
Date:   Fri, 5 Feb 2021 22:48:53 +0100
From:   Heiner Kallweit <hkallweit1@...il.com>
To:     Jakub Kicinski <kuba@...nel.org>,
        David Miller <davem@...emloft.net>,
        Realtek linux nic maintainers <nic_swsd@...ltek.com>
Cc:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: [PATCH net-next] r8169: don't try to disable interrupts if NAPI is
 scheduled already

There's no benefit in trying to disable interrupts if NAPI is
scheduled already. This allows us to save a PCI write in this case.

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 eb4c2e678..c15c285a0 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4544,8 +4544,10 @@ static irqreturn_t rtl8169_interrupt(int irq, void *dev_instance)
 		rtl_schedule_task(tp, RTL_FLAG_TASK_RESET_PENDING);
 	}
 
-	rtl_irq_disable(tp);
-	napi_schedule(&tp->napi);
+	if (napi_schedule_prep(&tp->napi)) {
+		rtl_irq_disable(tp);
+		__napi_schedule(&tp->napi);
+	}
 out:
 	rtl_ack_events(tp, status);
 
-- 
2.30.0