Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 3 Jun 2021 06:14:52 -0700
From:   Richard Cochran <richardcochran@gmail.com>
To:     Guangbin Huang <huangguangbin2@huawei.com>
Cc:     davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, salil.mehta@huawei.com,
        lipeng321@huawei.com, tanhuazhong@huawei.com
Subject: Re: [RESEND net-next 1/2] net: hns3: add support for PTP
Message-ID: <20210603131452.GA6216@hoboy.vegasvil.org>
References: <1622602664-20274-1-git-send-email-huangguangbin2@huawei.com>
 <1622602664-20274-2-git-send-email-huangguangbin2@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1622602664-20274-2-git-send-email-huangguangbin2@huawei.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

On Wed, Jun 02, 2021 at 10:57:43AM +0800, Guangbin Huang wrote:

> @@ -4342,12 +4352,34 @@ static void hclge_periodic_service_task(struct hclge_dev *hdev)
>  	hclge_task_schedule(hdev, delta);
>  }
>  
> +static void hclge_ptp_service_task(struct hclge_dev *hdev)
> +{
> +	if (!test_bit(HCLGE_STATE_PTP_EN, &hdev->state) ||
> +	    !test_bit(HCLGE_STATE_PTP_TX_HANDLING, &hdev->state) ||
> +	    !time_is_before_jiffies(hdev->ptp->tx_start + HZ))
> +		return;
> +
> +	/* to prevent concurrence with the irq handler, disable vector0
> +	 * before handling ptp service task.
> +	 */
> +	disable_irq(hdev->misc_vector.vector_irq);

This won't work.  After all, the ISR thread might already be running.
Use a proper spinlock instead.

> +	/* check HCLGE_STATE_PTP_TX_HANDLING here again, since the irq
> +	 * handler may handle it just before disable_irq().
> +	 */
> +	if (test_bit(HCLGE_STATE_PTP_TX_HANDLING, &hdev->state))
> +		hclge_ptp_clean_tx_hwts(hdev);
> +
> +	enable_irq(hdev->misc_vector.vector_irq);
> +}

Thanks,
Richard