Re: [tipc-discussion] [net-next v1] tipc: introduce new socket option TIPC_SOCK_RECVQ_USED

[David M. <da...@da...>]

From: Jon Maloy <jon...@er...>
Date: Fri, 19 Apr 2019 21:51:31 +0000

> 
> 
>> -----Original Message-----
>> From: net...@vg... <net...@vg...>
>> On Behalf Of David Miller
>> Sent: 19-Apr-19 17:41
>> To: Tung Quang Nguyen <tun...@de...>
>> Cc: ne...@vg...; tip...@li...
>> Subject: Re: [tipc-discussion][net-next v1] tipc: introduce new socket option
>> TIPC_SOCK_RECVQ_USED
>> 
>> From: Tung Nguyen <tun...@de...>
>> Date: Thu, 18 Apr 2019 21:02:19 +0700
>> 
>> > When using TIPC_SOCK_RECVQ_DEPTH for getsockopt(), it returns the
>> > number of buffers in receive socket buffer which is not so helpful for
>> > user space applications.
>> >
>> > This commit introduces the new option TIPC_SOCK_RECVQ_USED which
>> > returns the current allocated bytes of the receive socket buffer.
>> > This helps user space applications dimension its buffer usage to avoid
>> > buffer overload issue.
>> >
>> > Signed-off-by: Tung Nguyen <tun...@de...>
>> 
>> TIPC folks, please review.
> 
> Acked-by: Jon Maloy <jon...@er...>

Applied, thanks for reviewing.

> It would of course be nicer if we could recycle
> TIPC_SOCK_RECV_QUEUE_DEPTH for this purpose, but that would mean
> altering the current ABI and incur a (probably very low) risk of
> breaking existing application.  I am not particularly happy with
> this, but do we have users who claim it would be useful for them.

Better safe than sorry when it comes to user facing ABIs.