by Chuck Lever III

[permalink] [raw]

Subject: Re: [PATCH v2 08/10] svcrdma: Add backward direction service for RPC/RDMA transport

On Jun 2, 2015, at 11:30 AM, J. Bruce Fields <[email protected]> wrote:

> On Mon, Jun 01, 2015 at 04:45:26PM -0400, Chuck Lever wrote:
>>
>> On Jun 1, 2015, at 4:26 PM, J. Bruce Fields <[email protected]> wrote:
>>
>>> On Tue, May 26, 2015 at 01:49:45PM -0400, Chuck Lever wrote:
>>>> Introduce some pre-requisite infrastructure needed for handling
>>>> RPC/RDMA bi-direction on the client side.
>>>>
>>>> On NFSv4.1 mount points, the client uses this transport endpoint to
>>>> receive backward direction calls and route replies back to the
>>>> NFS server.
>>>
>>> Am I missing something, or is this pretty much dead code for now?
>>>
>>> In which case, I'd rather wait on it.
>>
>> When I submit the client-side backchannel patches, should I submit
>> this patch through Anna and request your Acked-by?
>
> Sure, feel free to add my Acked-by.
>
> Or I guess I won't worry too much about some dead code if the
> client-side patches are coming soon.

There are more pre-requisites on the client than there are on the server.
I anticipate it will be at least two more merge windows before the client
will be ready to merge backchannel support.

I?ll add this patch back into the client backchannel series.

> Whatever's simplest for you.
>
> --b.
>
>>
>>
>>> --b.
>>>
>>>>
>>>> Signed-off-by: Chuck Lever <[email protected]>
>>>> ---
>>>>
>>>> include/linux/sunrpc/svc_rdma.h | 6 +++
>>>> include/linux/sunrpc/xprt.h | 1 +
>>>> net/sunrpc/xprtrdma/svc_rdma.c | 6 +++
>>>> net/sunrpc/xprtrdma/svc_rdma_transport.c | 59 ++++++++++++++++++++++++++++++
>>>> 4 files changed, 71 insertions(+), 1 deletions(-)
>>>>
>>>> diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h
>>>> index cb94ee4..0e7234d 100644
>>>> --- a/include/linux/sunrpc/svc_rdma.h
>>>> +++ b/include/linux/sunrpc/svc_rdma.h
>>>> @@ -231,9 +231,13 @@ extern void svc_rdma_put_frmr(struct svcxprt_rdma *,
>>>> struct svc_rdma_fastreg_mr *);
>>>> extern void svc_sq_reap(struct svcxprt_rdma *);
>>>> extern void svc_rq_reap(struct svcxprt_rdma *);
>>>> -extern struct svc_xprt_class svc_rdma_class;
>>>> extern void svc_rdma_prep_reply_hdr(struct svc_rqst *);
>>>>
>>>> +extern struct svc_xprt_class svc_rdma_class;
>>>> +#ifdef CONFIG_SUNRPC_BACKCHANNEL
>>>> +extern struct svc_xprt_class svc_rdma_bc_class;
>>>> +#endif
>>>> +
>>>> /* svc_rdma.c */
>>>> extern int svc_rdma_init(void);
>>>> extern void svc_rdma_cleanup(void);
>>>> diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
>>>> index 8b93ef5..693f9f1 100644
>>>> --- a/include/linux/sunrpc/xprt.h
>>>> +++ b/include/linux/sunrpc/xprt.h
>>>> @@ -150,6 +150,7 @@ enum xprt_transports {
>>>> XPRT_TRANSPORT_TCP = IPPROTO_TCP,
>>>> XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC,
>>>> XPRT_TRANSPORT_RDMA = 256,
>>>> + XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC,
>>>> XPRT_TRANSPORT_LOCAL = 257,
>>>> };
>>>>
>>>> diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c
>>>> index 8eedb60..7a18ae4 100644
>>>> --- a/net/sunrpc/xprtrdma/svc_rdma.c
>>>> +++ b/net/sunrpc/xprtrdma/svc_rdma.c
>>>> @@ -244,6 +244,9 @@ void svc_rdma_cleanup(void)
>>>> unregister_sysctl_table(svcrdma_table_header);
>>>> svcrdma_table_header = NULL;
>>>> }
>>>> +#ifdef CONFIG_SUNRPC_BACKCHANNEL
>>>> + svc_unreg_xprt_class(&svc_rdma_bc_class);
>>>> +#endif
>>>> svc_unreg_xprt_class(&svc_rdma_class);
>>>> kmem_cache_destroy(svc_rdma_map_cachep);
>>>> kmem_cache_destroy(svc_rdma_ctxt_cachep);
>>>> @@ -291,6 +294,9 @@ int svc_rdma_init(void)
>>>>
>>>> /* Register RDMA with the SVC transport switch */
>>>> svc_reg_xprt_class(&svc_rdma_class);
>>>> +#ifdef CONFIG_SUNRPC_BACKCHANNEL
>>>> + svc_reg_xprt_class(&svc_rdma_bc_class);
>>>> +#endif
>>>> return 0;
>>>> err1:
>>>> kmem_cache_destroy(svc_rdma_map_cachep);
>>>> diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
>>>> index 3b4c2ff..9b8bccd 100644
>>>> --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
>>>> +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
>>>> @@ -56,6 +56,7 @@
>>>>
>>>> #define RPCDBG_FACILITY RPCDBG_SVCXPRT
>>>>
>>>> +static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *, int);
>>>> static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
>>>> struct net *net,
>>>> struct sockaddr *sa, int salen,
>>>> @@ -95,6 +96,64 @@ struct svc_xprt_class svc_rdma_class = {
>>>> .xcl_ident = XPRT_TRANSPORT_RDMA,
>>>> };
>>>>
>>>> +#if defined(CONFIG_SUNRPC_BACKCHANNEL)
>>>> +static struct svc_xprt *svc_rdma_bc_create(struct svc_serv *, struct net *,
>>>> + struct sockaddr *, int, int);
>>>> +static void svc_rdma_bc_detach(struct svc_xprt *);
>>>> +static void svc_rdma_bc_free(struct svc_xprt *);
>>>> +
>>>> +static struct svc_xprt_ops svc_rdma_bc_ops = {
>>>> + .xpo_create = svc_rdma_bc_create,
>>>> + .xpo_detach = svc_rdma_bc_detach,
>>>> + .xpo_free = svc_rdma_bc_free,
>>>> + .xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr,
>>>> + .xpo_secure_port = svc_rdma_secure_port,
>>>> +};
>>>> +
>>>> +struct svc_xprt_class svc_rdma_bc_class = {
>>>> + .xcl_name = "rdma-bc",
>>>> + .xcl_owner = THIS_MODULE,
>>>> + .xcl_ops = &svc_rdma_bc_ops,
>>>> + .xcl_max_payload = (1024 - RPCRDMA_HDRLEN_MIN),
>>>> + .xcl_ident = XPRT_TRANSPORT_BC_RDMA,
>>>> +};
>>>> +
>>>> +static struct svc_xprt *svc_rdma_bc_create(struct svc_serv *serv,
>>>> + struct net *net,
>>>> + struct sockaddr *sa, int salen,
>>>> + int flags)
>>>> +{
>>>> + struct svcxprt_rdma *cma_xprt;
>>>> + struct svc_xprt *xprt;
>>>> +
>>>> + cma_xprt = rdma_create_xprt(serv, 0);
>>>> + if (!cma_xprt)
>>>> + return ERR_PTR(-ENOMEM);
>>>> + xprt = &cma_xprt->sc_xprt;
>>>> +
>>>> + svc_xprt_init(net, &svc_rdma_bc_class, xprt, serv);
>>>> + serv->sv_bc_xprt = xprt;
>>>> +
>>>> + dprintk("svcrdma: %s(%p)\n", __func__, xprt);
>>>> + return xprt;
>>>> +}
>>>> +
>>>> +static void svc_rdma_bc_detach(struct svc_xprt *xprt)
>>>> +{
>>>> + dprintk("svcrdma: %s(%p)\n", __func__, xprt);
>>>> +}
>>>> +
>>>> +static void svc_rdma_bc_free(struct svc_xprt *xprt)
>>>> +{
>>>> + struct svcxprt_rdma *rdma =
>>>> + container_of(xprt, struct svcxprt_rdma, sc_xprt);
>>>> +
>>>> + dprintk("svcrdma: %s(%p)\n", __func__, xprt);
>>>> + if (xprt)
>>>> + kfree(rdma);
>>>> +}
>>>> +#endif /* CONFIG_SUNRPC_BACKCHANNEL */
>>>> +
>>>> struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
>>>> {
>>>> struct svc_rdma_op_ctxt *ctxt;
>>
>> --
>> Chuck Lever
>> chuck[dot]lever[at]oracle[dot]com
>>
>>

--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com

2015-06-03 19:47:42

by J. Bruce Fields

[permalink] [raw]

Subject: Re: [PATCH v2 08/10] svcrdma: Add backward direction service for RPC/RDMA transport

On Wed, Jun 03, 2015 at 03:49:13PM -0400, Chuck Lever wrote:
>
> On Jun 2, 2015, at 11:30 AM, J. Bruce Fields <[email protected]> wrote:
>
> > On Mon, Jun 01, 2015 at 04:45:26PM -0400, Chuck Lever wrote:
> >>
> >> On Jun 1, 2015, at 4:26 PM, J. Bruce Fields <[email protected]> wrote:
> >>
> >>> On Tue, May 26, 2015 at 01:49:45PM -0400, Chuck Lever wrote:
> >>>> Introduce some pre-requisite infrastructure needed for handling
> >>>> RPC/RDMA bi-direction on the client side.
> >>>>
> >>>> On NFSv4.1 mount points, the client uses this transport endpoint to
> >>>> receive backward direction calls and route replies back to the
> >>>> NFS server.
> >>>
> >>> Am I missing something, or is this pretty much dead code for now?
> >>>
> >>> In which case, I'd rather wait on it.
> >>
> >> When I submit the client-side backchannel patches, should I submit
> >> this patch through Anna and request your Acked-by?
> >
> > Sure, feel free to add my Acked-by.
> >
> > Or I guess I won't worry too much about some dead code if the
> > client-side patches are coming soon.
>
> There are more pre-requisites on the client than there are on the server.
> I anticipate it will be at least two more merge windows before the client
> will be ready to merge backchannel support.
>
> I’ll add this patch back into the client backchannel series.

OK.--b.