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From:   Paul Thomas <pthomas8589@gmail.com>
Date:   Mon, 11 Jan 2021 14:45:54 -0500
Message-ID: <CAD56B7fYivPF33BhXWDPskYqNE5jRxd-sA=6+ushNXhyiCrwiQ@mail.gmail.com>
Subject: net: macb: can macb use __napi_schedule_irqoff() instead of __napi_schedule()
To:     Nicolas Ferre <nicolas.ferre@microchip.com>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Russell King <linux@armlinux.org.uk>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        netdev@vger.kernel.org,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-riscv@lists.infradead.org
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Hello, recently I was doing a lot of tracing/profiling to understand
an issue we were having. Anyway, during this I ran across
__napi_schedule_irqoff() where the comment in dev.c says "Variant of
__napi_schedule() assuming hard irqs are masked".

It looks like the queue_writel(queue, IDR, bp->rx_intr_mask); call
just before the __napi_schedule() call in macb_main.c is doing this
hard irq masking? So could it change to be like this?

--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -1616,7 +1623,7 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id)

                        if (napi_schedule_prep(&queue->napi)) {
                                netdev_vdbg(bp->dev, "scheduling RX softirq\n");
-                               __napi_schedule(&queue->napi);
+                               __napi_schedule_irqoff(&queue->napi);
                        }
                }

-Paul