From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shimoda, Yoshihiro" <yoshihiro.shimoda.uh@renesas.com>
Subject: Re: [PATCH v3 6/6] net: sh_eth: use NAPI
Date: Tue, 15 May 2012 18:46:25 +0900
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 <20120514.185034.399229364191924851.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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2012/05/15 14:07, David Miller wrote:
> From: "Shimoda, Yoshihiro" <yoshihiro.shimoda.uh@renesas.com>
> Date: Tue, 15 May 2012 13:47:44 +0900
> 
>> 2012/05/15 7:50, David Miller wrote:
>>> You need strict synchronization between your TX queueing and TX
>>> liberation flows.  So that queue stop and wake are only performed
>>> at the correct moment.
>>
>> I will add netif_queue_stopped() in the sh_eth_poll().
> 
> That doesn't fix the bug.  What if someone transmits a packet and
> fills the TX queue between the netif_queue_stopped() test and the
> call to netif_wake_queue()?
> 
> Adding another test doesn't create the necessary synchronization.
> 

Thank you for the reply again.
I will modify the code as the following. Is it correct?

	if (txfree_num) {
		netif_tx_lock(ndev);
		if (netif_queue_stopped(ndev))
			netif_wake_queue(ndev);
		netif_tx_unlock(ndev);
	}

Best regards,
Yoshihiro Shimoda