Re: [PATCH bpf 2/3] devmap: Add missing bulk queue free

[Toshiaki Makita <toshiaki.makita1@gmail.com>]

On 19/06/14 (金) 20:58:06, Jesper Dangaard Brouer wrote:
> On Fri, 14 Jun 2019 17:20:14 +0900
> Toshiaki Makita <toshiaki.makita1@gmail.com> wrote:
> 
>> dev_map_free() forgot to free bulk queue when freeing its entries.
>>
>> Fixes: 5d053f9da431 ("bpf: devmap prepare xdp frames for bulking")
>> Signed-off-by: Toshiaki Makita <toshiaki.makita1@gmail.com>
>> ---
>>   kernel/bpf/devmap.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
>> index e001fb1..a126d95 100644
>> --- a/kernel/bpf/devmap.c
>> +++ b/kernel/bpf/devmap.c
>> @@ -186,6 +186,7 @@ static void dev_map_free(struct bpf_map *map)
>>   		if (!dev)
>>   			continue;
>>   
>> +		free_percpu(dev->bulkq);
>>   		dev_put(dev->dev);
>>   		kfree(dev);
>>   	}
> 
> Do we need to call need to call dev_map_flush_old() before
> free_percpu(dev->bulkq) ?
> 
> Looking the code, I guess this is not needed as, above we are ensuring
> all pending flush operations have completed.

My understanding is the same. The code waits for NAPI to flush the 
queue, so no need for dev_map_flush_old().

> 
> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>

Thanks!

Toshiaki Makita