Subject: Re: [PATCH net-next 1/2] igb: Stop PTP related workqueues if aren't necessary

From: Leon Romanovsky <[email-masked]>
Date: Sun, 13 Aug 2023 12:01:07 +0300

On Thu, Aug 10, 2023 at 10:54:09AM -0700, Tony Nguyen wrote:
> From: Alessio Igor Bogani <[email-masked]>
> 
> The workqueues ptp_tx_work and ptp_overflow_work are unconditionally allocated
> by igb_ptp_init(). Stop them if aren't necessary (ptp_clock_register() fails
> and CONFIG_PTP is disabled).
> 
> Signed-off-by: Alessio Igor Bogani <[email-masked]>
> Tested-by: Pucha Himasekhar Reddy <[email-masked]> (A Contingent worker at Intel)
> Signed-off-by: Tony Nguyen <[email-masked]>
> ---
>  drivers/net/ethernet/intel/igb/igb_ptp.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c
> index 405886ee5261..02276c922ac0 100644
> --- a/drivers/net/ethernet/intel/igb/igb_ptp.c
> +++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
> @@ -1406,7 +1406,13 @@ void igb_ptp_init(struct igb_adapter *adapter)
>  		dev_info(&adapter->pdev->dev, "added PHC on %s\n",
>  			 adapter->netdev->name);
>  		adapter->ptp_flags |= IGB_PTP_ENABLED;
> +		return;
>  	}
> +
> +	if (adapter->ptp_flags & IGB_PTP_OVERFLOW_CHECK)
> +		cancel_delayed_work_sync(&adapter->ptp_overflow_work);
> +
> +	cancel_work_sync(&adapter->ptp_tx_work);

Is it possible to move work initialization to be after call to ptp_clock_register()?

diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c
index 405886ee5261..56fd2b0fe70c 100644
--- a/drivers/net/ethernet/intel/igb/igb_ptp.c
+++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
@@ -1386,11 +1386,6 @@ void igb_ptp_init(struct igb_adapter *adapter)
        }
 
        spin_lock_init(&adapter->tmreg_lock);
-       INIT_WORK(&adapter->ptp_tx_work, igb_ptp_tx_work);
-
-       if (adapter->ptp_flags & IGB_PTP_OVERFLOW_CHECK)
-               INIT_DELAYED_WORK(&adapter->ptp_overflow_work,
-                                 igb_ptp_overflow_check);
 
        adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
        adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
@@ -1407,6 +1402,15 @@ void igb_ptp_init(struct igb_adapter *adapter)
                         adapter->netdev->name);
                adapter->ptp_flags |= IGB_PTP_ENABLED;
        }
+
+       if (!adapter->ptp_clock)
+               return;
+
+       INIT_WORK(&adapter->ptp_tx_work, igb_ptp_tx_work);
+
+       if (adapter->ptp_flags & IGB_PTP_OVERFLOW_CHECK)
+               INIT_DELAYED_WORK(&adapter->ptp_overflow_work,
+                                 igb_ptp_overflow_check);
 }
 
 /**

>  }
>  /**
> -- 
> 2.38.1