Re: [PATCH net-next v2] net: pktgen: return bool from __pktgen_NN_threads()

[Hangbin Liu]

On Sun, Sep 27, 2026 at 09:54:05PM +0800, Chengfeng Ye wrote:
> Callers of __pktgen_NN_threads() only check whether a pktgen_dev was
> found. Returning the pointer exposes it outside the helper even though
> neither caller uses the object itself.
> 
> Return bool instead and keep the pktgen_dev pointer internal to the
> helper.
> 
> Suggested-by: Paolo Abeni <pabeni@xxxxxxxxxx>
> Signed-off-by: Chengfeng Ye <nicoyip.dev@xxxxxxxxx>
> ---
> Changes in v2:
> - Rebase directly onto the current net-next tree, independently of the
>   deferred RCU lifetime fix.
> - Update the commit message for the current helper implementation.
> 
> Link: https://lore.kernel.org/netdev/20260825185313.239861-1-nicoyip.dev@xxxxxxxxx/ [v1]
> ---
>  net/core/pktgen.c | 17 +++++++----------
>  1 file changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/net/core/pktgen.c b/net/core/pktgen.c
> index 7f81aed46672..a89cb0760821 100644
> --- a/net/core/pktgen.c
> +++ b/net/core/pktgen.c
> @@ -2024,11 +2024,11 @@ static const struct proc_ops pktgen_thread_proc_ops = {
>  };
>  
>  /* Think find or remove for NN */
> -static struct pktgen_dev *__pktgen_NN_threads(const struct pktgen_net *pn,
> -					      const char *ifname, int remove)
> +static bool __pktgen_NN_threads(const struct pktgen_net *pn,
> +				const char *ifname, int remove)
>  {
>  	struct pktgen_thread *t;
> -	struct pktgen_dev *pkt_dev = NULL;
> +	struct pktgen_dev *pkt_dev;
>  	bool exact = (remove == FIND);
>  
>  	list_for_each_entry(t, &pn->pktgen_threads, th_list) {
> @@ -2038,10 +2038,10 @@ static struct pktgen_dev *__pktgen_NN_threads(const struct pktgen_net *pn,
>  				pkt_dev->removal_mark = 1;
>  				t->control |= T_REMDEV;
>  			}
> -			break;
> +			return true;
>  		}
>  	}
> -	return pkt_dev;
> +	return false;
>  }
>  
>  /*
> @@ -2049,7 +2049,6 @@ static struct pktgen_dev *__pktgen_NN_threads(const struct pktgen_net *pn,
>   */
>  static void pktgen_mark_device(const struct pktgen_net *pn, const char *ifname)
>  {
> -	struct pktgen_dev *pkt_dev = NULL;
>  	const int max_tries = 10, msec_per_try = 125;
>  	int i = 0;
>  
> @@ -2058,8 +2057,7 @@ static void pktgen_mark_device(const struct pktgen_net *pn, const char *ifname)
>  
>  	while (1) {
>  
> -		pkt_dev = __pktgen_NN_threads(pn, ifname, REMOVE);
> -		if (pkt_dev == NULL)
> +		if (!__pktgen_NN_threads(pn, ifname, REMOVE))
>  			break;	/* success */
>  
>  		mutex_unlock(&pktgen_thread_lock);
> @@ -3835,8 +3833,7 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname)
>  
>  	/* We don't allow a device to be on several threads */
>  
> -	pkt_dev = __pktgen_NN_threads(t->net, ifname, FIND);
> -	if (pkt_dev) {
> +	if (__pktgen_NN_threads(t->net, ifname, FIND)) {
>  		pr_err("ERROR: interface already used\n");
>  		return -EBUSY;
>  	}
> -- 
> 2.43.0

Reviewed-by: Hangbin Liu <liuhangbin@xxxxxxxxxx>