Re: [PATCH bpf-next v2 05/11] bpf: add hashtab support for bpf_for_each_map_elem() helper

[Yonghong Song <yhs@xxxxxx>]

On 2/22/21 2:56 PM, Alexei Starovoitov wrote:
> On Wed, Feb 17, 2021 at 10:18:08AM -0800, Yonghong Song wrote:
> > +			ret = BPF_CAST_CALL(callback_fn)((u64)(long)map,
> > +					(u64)(long)key, (u64)(long)val,
> > +					(u64)(long)callback_ctx, 0);
> > +			if (ret) {
> > +				rcu_read_unlock();
> > +				ret = (ret == 1) ? 0 : -EINVAL;
> > +				goto out;
>
> There is a tnum(0,1) check in patch 4.
> I'm missing the purpose of this additional check.

I missed this one after I added tnum(0, 1) checking. Will fix in the 
next revision.

> > +			}
> > +		}
> > +		rcu_read_unlock();
> > +	}
> > +out:
> > +	migrate_enable();
> > +	return ret ?: num_calls;
> > +}