Re: [RFC PATCH v1 2/2] chnet: Implement `get_thread()` and `put_thread()` function

[Ammar Nofan Faizi <ammar_nofan_faizi@yahoo.com>]

On 8/29/22 12:24 PM, Alviro Iskandar Setiawan wrote:
> On Mon, Aug 29, 2022 at 12:17 PM Alviro Iskandar Setiawan wrote:
>> On Mon, Aug 29, 2022 at 11:54 AM Ammar Nofan Faizi wrote:
>>> On 8/29/22 11:41 AM, Alviro Iskandar Setiawan wrote:
>>>> On Mon, Aug 29, 2022 at 8:11 AM Ammar Faizi wrote:
>>>>> +static base::Thread *get_thread(void)
>>>>> +{
>>>>> +       const uint32_t max_ch_thpool = g_max_ch_thpool;
>>>>> +       const uint32_t nr_ref_split = 2048;
>>>>> +       struct ch_thpool **thp;
>>>>> +       struct ch_thpool *ret = nullptr;
>>>>> +       struct ch_thpool *tmp;
>>>>> +       uint32_t min_ref_idx;
>>>>> +       uint32_t min_ref;
>>>>> +       uint32_t i;
>>>>> +
>>>>> +       g_thpool_lock_.lock();
>>>>> +       thp = g_thpool;
>>>>> +       if (!thp) {
>>>>> +               g_thpool_lock_.unlock();
>>>>> +               return nullptr;
>>>>> +       }
>>>>
>>>> in what situation @thp can be nullptr?
>>>
>>> When the chnet_global_destroy() is called.
> 
> btw, i missed a case on the chnet construction, you do
> 
>     thread_(*get_thread()),
> 
> if get_thread() returns a nullptr, the @thread_ will become a
> reference to a nullptr, it will definitely break, how do you handle
> this?

I don't think we need to handle that. If @thp ever be a nullptr in a
get_thread() call, then it's a misuse of the API. We must never call
get_thread() after chnet_global_destroy() is called. It doesn't make
much sense to have this situation.

-- 
Ammar Faizi