[dpdk-dev] [PATCH v4 04/10] power: add simple power management API and callback

[Burakov, Anatoly]

On 09-Oct-20 5:51 PM, Ananyev, Konstantin wrote:

>>>
>>>> +case RTE_POWER_MGMT_TYPE_PAUSE:
>>>> +rte_eth_remove_rx_callback(port_id, queue_id,
>>>> +   queue_cfg->cur_cb);
>>>> +break;
>>>> +case RTE_POWER_MGMT_TYPE_SCALE:
>>>> +rte_power_freq_max(lcore_id);
>>>> +rte_eth_remove_rx_callback(port_id, queue_id,
>>>> +   queue_cfg->cur_cb);
>>>> +rte_power_exit(lcore_id);
>>>> +break;
>>>> +}
>>>> +/* it's not recommend to free callback instance here.
>>>> + * it cause memory leak which is a known issue.
>>>> + */
>>>> +queue_cfg->cur_cb = NULL;
>>>> +queue_cfg->pwr_mgmt_state = PMD_MGMT_DISABLED;
>>>> +port_cfg[port_id].ref_cnt--;
>>>> +
>>>> +if (port_cfg[port_id].ref_cnt == 0) {
>>>> +rte_free(port_cfg[port_id].queue_cfg);
>>>
>>> It is not safe to do so, unless device is already stopped.
>>> Otherwise you need some sync mechanism here (hand-made as bpf lib, or rcu online/offline, or...)
>>
>> Not sure what you mean. We're not freeing the callback structure, we're
>> freeing the local data structure holding the per-port status.
> 
> What is the difference?
> You still trying to free memory that might be used by your DP thread
> that still executes the callback.

Welp, you're right :/ I'll see what i can do to fix it.

-- 
Thanks,
Anatoly