On 03/30/2018 03:44 PM, Kirill Tkhai wrote:
> Hi, Eric,
>
> thanks for more small patches in v2. One comment below.
>
>> -
>> -struct inet_frag_bucket {
>> - struct hlist_head chain;
>> - spinlock_t chain_lock;
>> + struct netns_frags *net;
>> + struct rcu_head rcu;
>
> inet_frag_destroy() calls call_rcu() after frags are destroyed.
> It looks like we may place this rcu in union with fragments and
> fragments_tail and to sa
No, because I am planning to free skbs in the rcu call back very shortly.
As I mentioned, I believe we could use pure RCU lookups, without grabing a
reference and then release it after packet is processed/added to the queue.
This is not urgent, I wanted to get the first patches for review before doing
this final step, as I do not expect more than 5 % improvement from this
optimization.
Also note that the ipq structure is 192 bytes, nicely using 3 cache lines.
Trying to save 16 bytes will likely reduce performance, unless we force padding
to reach 192 bytes again :)
