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Subject: Re: [RFC PATCH 3/5] ixgbe: Add support for ndo_ll_poll
From: Ben Hutchings <bhutchings@solarflare.com>
To: Eliezer Tamir <eliezer.tamir@linux.jf.intel.com>
CC: <linux-kernel@vger.kernel.org>, <netdev@vger.kernel.org>,
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        Eliezer Tamir <eliezer@tamir.org.il>
Date: Tue, 5 Mar 2013 17:26:50 +0000
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On Wed, 2013-02-27 at 09:56 -0800, Eliezer Tamir wrote:
> Add the ixgbe driver code implementing ndo_ll_poll.
> It should be easy for other drivers to do something similar
> in order to enable support for CONFIG_INET_LL_RX_POLL

Yes... in fact I wonder whether the lock and state couldn't be added to
napi_struct instead of being driver-specific.

[...]
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
[...]
>  static void ixgbe_napi_disable_all(struct ixgbe_adapter *adapter)
>  {
>  	int q_idx;
>  
> -	for (q_idx = 0; q_idx < adapter->num_q_vectors; q_idx++)
> +	local_bh_disable(); /* for ixgbe_qv_lock_napi() */
> +	for (q_idx = 0; q_idx < adapter->num_q_vectors; q_idx++) {
>  		napi_disable(&adapter->q_vector[q_idx]->napi);
> +		while (!ixgbe_qv_lock_napi(adapter->q_vector[q_idx])) {
> +			pr_info("QV %d locked\n", q_idx);
> +			msleep(1);
> +		}
> +	}
> +	local_bh_enable();
>  }

Sleeping with preemption disabled?

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
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