RE: [Patch v5 08/21] CIFS: SMBD: Upper layer reconnects to SMB Direct session

From: Long Li
Date: Sun Nov 05 2017 - 14:20:10 EST




> -----Original Message-----
> From: samba-technical [mailto:samba-technical-bounces@xxxxxxxxxxxxxxx]
> On Behalf Of Long Li via samba-technical
> Sent: Sunday, November 5, 2017 10:37 AM
> To: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>; Pavel Shilovsky
> <piastryyy@xxxxxxxxx>
> Cc: linux-cifs <linux-cifs@xxxxxxxxxxxxxxx>; Stephen Hemminger
> <sthemmin@xxxxxxxxxxxxx>; linux-rdma@xxxxxxxxxxxxxxx; samba-technical
> <samba-technical@xxxxxxxxxxxxxxx>; Kernel Mailing List <linux-
> kernel@xxxxxxxxxxxxxxx>; Steve French <sfrench@xxxxxxxxx>
> Subject: RE: [Patch v5 08/21] CIFS: SMBD: Upper layer reconnects to SMB
> Direct session
>
> > -----Original Message-----
> > From: Matthew Wilcox
> > Sent: Wednesday, November 1, 2017 12:45 PM
> > To: Pavel Shilovsky <piastryyy@xxxxxxxxx>; Long Li
> > <longli@xxxxxxxxxxxxx>
> > Cc: Steve French <sfrench@xxxxxxxxx>; linux-cifs <linux-
> > cifs@xxxxxxxxxxxxxxx>; samba-technical
> > <samba-technical@xxxxxxxxxxxxxxx>;
> > Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>; linux-
> > rdma@xxxxxxxxxxxxxxx; Tom Talpey <ttalpey@xxxxxxxxxxxxx>; Stephen
> > Hemminger <sthemmin@xxxxxxxxxxxxx>; Long Li <longli@xxxxxxxxxxxxx>
> > Subject: RE: [Patch v5 08/21] CIFS: SMBD: Upper layer reconnects to
> > SMB Direct session
> >
> > From: Pavel Shilovsky [mailto:piastryyy@xxxxxxxxx]
> > > 2017-10-18 16:09 GMT-07:00 Long Li <longli@xxxxxxxxxxxxxxxxxxxxxx>:
> > > > From: Long Li <longli@xxxxxxxxxxxxx>
> > > >
> > > > Do a reconnect on SMB Direct when it is used as the connection.
> > > > Reconnect
> > > can
> > > > happen for many reasons and it's mostly the decision of SMB2 upper
> > layer.
> > > >
> > > > Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
> > > > ---
> > > > fs/cifs/connect.c | 7 +++++++
> > > > 1 file changed, 7 insertions(+)
> > > >
> > > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index
> > > > 2c0b34a..8ca3c13 100644
> > > > --- a/fs/cifs/connect.c
> > > > +++ b/fs/cifs/connect.c
> > > > @@ -406,7 +406,14 @@ cifs_reconnect(struct TCP_Server_Info
> > > > *server)
> > > >
> > > > /* we should try only the port we connected to before */
> > > > mutex_lock(&server->srv_mutex);
> > > > +#ifdef CONFIG_CIFS_SMB_DIRECT
> > > > + if (server->rdma)
> > > > + rc = smbd_reconnect(server);
> > > > + else
> > > > + rc = generic_ip_connect(server);
> > >
> > > Minor: here and in other similar places we can remove #else part
> > > below and put #endif before else block above.
> > >
> > > > +#else
> > > > rc = generic_ip_connect(server);
> > > > +#endif
> >
> > I'd suggest rather:
> >
> > #ifdef CONFIG_CIFS_SMB_DIRECT
> > #define cifs_rdma_enabled(server) ((server)->rdma)
> > #else
> > #define cifs_rdma_enabled(server) 0
> > #endif
> >
> > Then we don't need an ifdef in the users, just:
> >
> > if (cifs_rdma_enabled(server))
> > rc = smbd_reconnect(server);
> > else
> > rc = generic_ip_connect(server);

It doesn't work well, because smbd_reconnect is defined when CONFIG_CIFS_SMB_DIRECT is set. Now the compiler is complaining it can't find this function. Maybe compiler is not smart enough :)

I have sent v6 for all the other comments.