Subject: Re: [PATCH v6 3/4] bpf: Implement function bpf_perf_event_read() that get the selected hardware PMU conuter

From: xiakaixu <[email-masked]>
Date: Wed, 5 Aug 2015 10:09:22 +0800

于 2015/8/5 1:55, Alexei Starovoitov 写道:
> On 8/4/15 1:58 AM, Kaixu Xia wrote:
>> +static int check_func_limit(struct bpf_map **mapp, int func_id)
> 
> how about 'check_map_func_compatibility' or 'check_map_func_affinity' ?
> 
>> +{
>> +    struct bpf_map *map = *mapp;
> 
> why pass pointer to a pointer? single pointer would be be fine.
> 
>> +    bool bool_map, bool_func;
>> +    int i;
>> +
>> +    if (!map)
>> +        return 0;
>> +
>> +    for (i = 0; i <= ARRAY_SIZE(func_limit); i++) {
>> +        bool_map = (map->map_type == func_limit[i].map_type);
>> +        bool_func = (func_id == func_limit[i].func_id);
>> +        /* only when map & func pair match it can continue.
>> +         * don't allow any other map type to be passed into
>> +         * the special func;
>> +         */
>> +        if (bool_map != bool_func)
>> +            return -EINVAL;
>> +    }
> 
> nice simplification!
> 
> the rest of the changes look good.
> please respin your next set against net-next.

Thanks for your review! I will follow them in the next set.
> .