Re: [PATCH] sched: add parentheses to if clause

[Stephen Hemminger <stephen@networkplumber.org>]

On Sat, 26 Feb 2022 22:55:30 +0800
Weiguo Li <liwg06@foxmail.com> wrote:

> Add parentheses to 'if' clause, otherwise will enlarged the
> chance of error return.
> 
> Fixes: 44c730b0e37971 ("sched: add PIE based congestion management")
> 
> Signed-off-by: Weiguo Li <liwg06@foxmail.com>
> ---
>  lib/sched/rte_pie.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/lib/sched/rte_pie.c b/lib/sched/rte_pie.c
> index cdb7bab697..51df403a25 100644
> --- a/lib/sched/rte_pie.c
> +++ b/lib/sched/rte_pie.c
> @@ -18,10 +18,10 @@ rte_pie_rt_data_init(struct rte_pie *pie)
>  		/* Allocate memory to use the PIE data structure */
>  		pie = rte_malloc(NULL, sizeof(struct rte_pie), 0);
>  
> -		if (pie == NULL)
> +		if (pie == NULL) {
>  			RTE_LOG(ERR, SCHED, "%s: Memory allocation fails\n", __func__);
> -
> -		return -1;
> +			return -1;
> +		}
>  	}
>  
>  	pie->active = 0;

This will make the test in test_pie.c fail.

The concept of passing NULL to the routine and expecting allocation
is bad idea because the allocated structure is never initialized.

Since rte_pie_rt_data_init(NULL) always returned -1.
It would make more sense to take out the rte_malloc().
And document it.

P.s: the routing should return a negative rte_errno instead of -1
as well.