Re: [PATCHv5 for-rc1 v5 4/8] RDMA/rxe: Implement dellink in rxe

[Zhu Yanjun <yanjun.zhu@xxxxxxxxx>]

在 2023/6/21 4:21, Bob Pearson 写道:
> On 4/28/23 04:39, Zhu Yanjun wrote:
> > From: Zhu Yanjun <yanjun.zhu@xxxxxxxxx>
> >
> > When running "rdma link del" command, dellink function will be called.
> > If the sock refcnt is greater than the refcnt needed for udp tunnel,
> > the sock refcnt will be decreased by 1.
> >
> > If equal, the last rdma link is removed. The udp tunnel will be
> > destroyed.
> >
> > Tested-by: Rain River <rain.1986.08.12@xxxxxxxxx>
> > Signed-off-by: Zhu Yanjun <yanjun.zhu@xxxxxxxxx>
> > ---
> >   drivers/infiniband/sw/rxe/rxe.c     | 12 +++++++++++-
> >   drivers/infiniband/sw/rxe/rxe_net.c | 17 +++++++++++++++--
> >   drivers/infiniband/sw/rxe/rxe_net.h |  1 +
> >   3 files changed, 27 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
> > index 0ce6adb43cfc..ebfabc6d6b76 100644
> > --- a/drivers/infiniband/sw/rxe/rxe.c
> > +++ b/drivers/infiniband/sw/rxe/rxe.c
> > @@ -166,10 +166,12 @@ void rxe_set_mtu(struct rxe_dev *rxe, unsigned int ndev_mtu)
> >   /* called by ifc layer to create new rxe device.
> >    * The caller should allocate memory for rxe by calling ib_alloc_device.
> >    */
> > +static struct rdma_link_ops rxe_link_ops;
> >   int rxe_add(struct rxe_dev *rxe, unsigned int mtu, const char *ibdev_name)
> >   {
> >   	rxe_init(rxe);
> >   	rxe_set_mtu(rxe, mtu);
> > +	rxe->ib_dev.link_ops = &rxe_link_ops;
> >   
> >   	return rxe_register_device(rxe, ibdev_name);
> >   }
> > @@ -206,9 +208,17 @@ static int rxe_newlink(const char *ibdev_name, struct net_device *ndev)
> >   	return err;
> >   }
> >   
> > -struct rdma_link_ops rxe_link_ops = {
> > +static int rxe_dellink(struct ib_device *dev)
> > +{
> > +	rxe_net_del(dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct rdma_link_ops rxe_link_ops = {
> >   	.type = "rxe",
> >   	.newlink = rxe_newlink,
> > +	.dellink = rxe_dellink,
> >   };
> >   
> >   static int __init rxe_module_init(void)
> > diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
> > index 3ca92e062800..4cc7de7b115b 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_net.c
> > +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> > @@ -530,6 +530,21 @@ int rxe_net_add(const char *ibdev_name, struct net_device *ndev)
> >   	return 0;
> >   }
> >   
> > +#define SK_REF_FOR_TUNNEL	2
> > +void rxe_net_del(struct ib_device *dev)
> > +{
> > +	if (refcount_read(&recv_sockets.sk6->sk->sk_refcnt) > SK_REF_FOR_TUNNEL)
> > +		__sock_put(recv_sockets.sk6->sk);
> > +	else
> > +		rxe_release_udp_tunnel(recv_sockets.sk6);
> > +
> > +	if (refcount_read(&recv_sockets.sk4->sk->sk_refcnt) > SK_REF_FOR_TUNNEL)
> > +		__sock_put(recv_sockets.sk4->sk);
> > +	else
> > +		rxe_release_udp_tunnel(recv_sockets.sk4);
> > +}
> > +#undef SK_REF_FOR_TUNNEL
> > +
> >   static void rxe_port_event(struct rxe_dev *rxe,
> >   			   enum ib_event_type event)
> >   {
> > @@ -689,8 +704,6 @@ int rxe_register_notifier(void)
> >   
> >   void rxe_net_exit(void)
> >   {
> > -	rxe_release_udp_tunnel(recv_sockets.sk6);
> > -	rxe_release_udp_tunnel(recv_sockets.sk4);
> >   	unregister_netdevice_notifier(&rxe_net_notifier);
> >   }
> These calls are moved to rxe_net_del which is called by an explicit unlink command.
> But if rxe_net_init fails and returns an error code this will never happen.
> This will result in leaking resources.

Thanks a lot. Bob.

Sure, if ipv6 tunnel fails to be created, the resource related with ipv4 
should be released.

I will fix it in the latest version.

Zhu Yanjun

> Bob
> >   
> > diff --git a/drivers/infiniband/sw/rxe/rxe_net.h b/drivers/infiniband/sw/rxe/rxe_net.h
> > index a222c3eeae12..f48f22f3353b 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_net.h
> > +++ b/drivers/infiniband/sw/rxe/rxe_net.h
> > @@ -17,6 +17,7 @@ struct rxe_recv_sockets {
> >   };
> >   
> >   int rxe_net_add(const char *ibdev_name, struct net_device *ndev);
> > +void rxe_net_del(struct ib_device *dev);
> >   
> >   int rxe_register_notifier(void);
> >   int rxe_net_init(void);