On 12/23/18 11:52 PM, bfields@xxxxxxxxxxxx wrote:
> On Sat, Dec 22, 2018 at 08:46:55PM +0300, Vasily Averin wrote:
>> On 12/21/18 4:00 AM, bfields@xxxxxxxxxxxx wrote:
>>> On Tue, Dec 18, 2018 at 02:55:15PM +0000, Trond Myklebust wrote:
>>>> No. We don't care about xpt_flags for the back channel because there is
>>>> no "server transport". The actual transport is stored in the 'struct
>>>> rpc_rqst', and is the struct rpc_xprt corresponding to the client
>>>> socket or RDMA channel.
>>>>
>>>> IOW: All we really need in svc_process_common() is to be able to run
>>>> rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(), and that can be passed
>>>> either as a pointer to the struct svc_xprt_ops itself.
>>>
>>> For what it's worth, I'd rather get rid of that op--it's an awfully
>>> roundabout way just to do "svc_putnl(resv, 0);" in the tcp case.
>>
>> Do you mean that svc_create_xprt(serv, "tcp-bc", ...) was used ONLY to call
>> svc_tcp_prep_reply_hdr() in svc_process_common() ?
>> And according call for rdma-bc does nothing useful at all?
>
> Right, in the rdma case it's:
>
> void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp)
> {
> }
>
>> I've just tried to remove svc_create_xprt() from xs_tcp_bc_up() and
>> just provide pointer to svc_tcp_prep_reply_hdr() in
>> svc_process_common() via per-netns sunrpc_net -- and seems it was
>> enough, my testcase worked correctly.
>>
>> Am I missed something probably? Should we really remove
>> svc_create_xprt( "tcp/rdma-bc"...) related stuff? ?
>
> Haven't looked carefully, but off the top of my head I can't see why
> that wouldn't work.
I've prepared new patch version removed svc_create_xprt( "tcp/rdma-bc"...)
as far as I see it works correctly.
I'm going to submit it tomorrow morning.
> I also tried some patches that replace that op by a flag bit (doesn't
> address the original problem here, just seemed like a simplification):
>
> git://linux-nfs.org/~bfields/linux-topics.git
>
> but I don't if that's compatible with what you've done.
>
> --b.
>
