Subject: Re: [PATCH 1/2 RFC] ath10k: move code out of the parameter list

From: Pat Erley <[email-masked]>
Date: Wed, 11 Mar 2015 12:41:09 -0500

On 03/11/2015 12:19 PM, Nicholas Mc Guire wrote:
> Putting code into the parameter list of wait_event_timeout() might be
> legal C-code but not really readable - the "inline" code is simply
> moved into a function and that passed to wait_event_timeout() as the
> condition.
>
> Signed-off-by: Nicholas Mc Guire <[email-masked]>
> ---
>
> Thanks to Bjorn Mork <[email-masked]> for clarifying my initial confusion !
>
> Patch was only compile tested with x86_64_defconfig + CONFIG_ATH_CARDS=m,
> CONFIG_ATH10K=m
>
> Patch is against 4.0-rc3 (localversion-next is -next-20150311)
>
>   drivers/net/wireless/ath/ath10k/mac.c |   32 ++++++++++++++++++--------------
>   1 file changed, 18 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
> index e8cc19f..7b27d99 100644
> --- a/drivers/net/wireless/ath/ath10k/mac.c
> +++ b/drivers/net/wireless/ath/ath10k/mac.c
> @@ -4463,11 +4463,25 @@ static int ath10k_set_rts_threshold(struct ieee80211_hw *hw, u32 value)
>   	return ret;
>   }
>
> +static bool check_htt_state(struct ath10k *ar, bool skip)
> +{
> +	bool empty;
> +
> +	spin_lock_bh(&ar->htt.tx_lock);
> +	empty = (ar->htt.num_pending_tx == 0);
> +	spin_unlock_bh(&ar->htt.tx_lock);
> +
> +	skip = (ar->state == ATH10K_STATE_WEDGED) ||
> +		test_bit(ATH10K_FLAG_CRASH_FLUSH,
> +			 &ar->dev_flags);
> +	return (empty || skip);
> +}
> +
>   static void ath10k_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
>   			 u32 queues, bool drop)
>   {
>   	struct ath10k *ar = hw->priv;
> -	bool skip;
> +	bool skip = false;
>   	int ret;
>
>   	/* mac80211 doesn't care if we really xmit queued frames or not
> @@ -4480,19 +4494,9 @@ static void ath10k_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
>   	if (ar->state == ATH10K_STATE_WEDGED)
>   		goto skip;
>
> -	ret = wait_event_timeout(ar->htt.empty_tx_wq, ({
> -			bool empty;
> -
> -			spin_lock_bh(&ar->htt.tx_lock);
> -			empty = (ar->htt.num_pending_tx == 0);
> -			spin_unlock_bh(&ar->htt.tx_lock);
> -
> -			skip = (ar->state == ATH10K_STATE_WEDGED) ||
> -			       test_bit(ATH10K_FLAG_CRASH_FLUSH,
> -					&ar->dev_flags);
> -
> -			(empty || skip);
> -		}), ATH10K_FLUSH_TIMEOUT_HZ);
> +	ret = wait_event_timeout(ar->htt.empty_tx_wq,
> +				 check_htt_state(ar, skip),
> +				 ATH10K_FLUSH_TIMEOUT_HZ);
>
>   	if (ret <= 0 || skip)
>   		ath10k_warn(ar, "failed to flush transmit queue (skip %i ar-state %i): %i\n",
>

Doesn't this change not assign to 'skip' in the calling function?  So 
you'd want to make it:

static bool check_htt_state(struct ath10k *ar, bool *skip)
{
	bool empty;

	spin_lock_bh(&ar->htt.tx_lock);
	empty = (ar->htt.num_pending_tx == 0);
	spin_unlock_bh(&ar->htt.tx_lock);

	*skip = (ar->state == ATH10K_STATE_WEDGED) ||
		test_bit(ATH10K_FLAG_CRASH_FLUSH,
			 &ar->dev_flags);
	return (empty || *skip);
}

ret = wait_event_timeout(ar->htt.empty_tx_wq,
				 check_htt_state(ar, &skip),
				 ATH10K_FLUSH_TIMEOUT_HZ);

To preserve the previous behavior?