Re: [PATCH net-next] net/packet: Add getsockopt support for PACKET_COPY_THRESH

[Juntong Deng]

On 2024/3/8 19:43, Willem de Bruijn wrote:
> Juntong Deng wrote:
> > Currently getsockopt does not support PACKET_COPY_THRESH,
> > and we are unable to get the value of PACKET_COPY_THRESH
> > socket option through getsockopt.
> >
> > This patch adds getsockopt support for PACKET_COPY_THRESH.
> >
> > Signed-off-by: Juntong Deng <juntong.deng@xxxxxxxxxxx>
> > ---
> >   net/packet/af_packet.c | 3 +++
> >   1 file changed, 3 insertions(+)
> >
> > diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
> > index 0db31ca4982d..65042edd1a97 100644
> > --- a/net/packet/af_packet.c
> > +++ b/net/packet/af_packet.c
> > @@ -4090,6 +4090,9 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
> >   	case PACKET_VNET_HDR_SZ:
> >   		val = READ_ONCE(po->vnet_hdr_sz);
> >   		break;
> > +	case PACKET_COPY_THRESH:
> > +		val = pkt_sk(sk)->copy_thresh;
> > +		break;
>
> This is probably a good opportunity to use READ_ONCE/WRITE_ONCE for
> this variable that can be modified and read concurrently.
>
> Alternatively I can fix up all three locations in a follow-on patch.
>
> No concerns with adding the getsockopt itself.
>
> >   	case PACKET_VERSION:
> >   		val = po->tp_version;
> >   		break;
> > --
> > 2.39.2

Thanks for reviewing.

So, do I need to send PATCH V2 to add READ_ONCE?

Or do you want you to use a follow-on patch to fix all three locations 
at once?