Re: [PATCH v4 net-next 8/9] net: add a hardware buffer management helper API

[Marcin Wojtas]

Hi Gregory,


> +int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num, gfp_t gfp)
> +{
> +       int err, i;
> +       unsigned long flags;
> +
> +       spin_lock_irqsave(&bm_pool->lock, flags);
> +       if (bm_pool->buf_num == bm_pool->size) {

'size' field is used as a 'frag_size' but here it means pool capacity.
I think it's better to keep 'size' for pool capacity and add
'buf_size' field to struct hwbm_pool.

> +               pr_warn("pool already filled\n");
> +               return bm_pool->buf_num;
> +       }
> +
> +       if (buf_num + bm_pool->buf_num > bm_pool->size) {
> +               pr_warn("cannot allocate %d buffers for pool\n",
> +                       buf_num);
> +               return 0;
> +       }
> +
> +       if ((buf_num + bm_pool->buf_num) < bm_pool->buf_num) {

What is a point of this condition? How possibly after checking if
capacity of pool is not exceeded, this one would ever be true?

> +               pr_warn("Adding %d buffers to the %d current buffers will overflow\n",
> +                       buf_num,  bm_pool->buf_num);
> +               return 0;
> +       }
> +

Best regards,
Marcin