[illumos-Developer] webrev for 1107

[Dan Kruchinin]

On Tue, Jun 14, 2011 at 12:45 AM, Vitaliy Gusev
<gusev.vitaliy at nexenta.com> wrote:
>>>
>>> No, do_one doesn't call do_poll_cots_action. I as mentioned early,
>>> call stack is:
>>>
>>>   poll_for_action
>>>        do_poll_cots_action
>>>             cots_listen_event
>>
>> Heh, your're right, I confused poll_for_actions with add_to_poll_list,
>> which is called by do_one.
>> But your point point opens several questions. First of all I need to
>> explain why we need OK_TPI_TYPE
>> instead of checking of nc_semantics on  NC_TPI_CLTS only.
>
>
> I think it creates kernel thread on each connect for COTS - so we can do it
> only on connect, whereas for udp it can be started at once.

Thanks for explanation, Vitaliy, now it makes sense.
XTI/TLI is very new thing for me, so correct me if I'm wrong trying to
clarify everything:
cots_listen_events catches connections from remote hosts - in case of
nfsd - and gives
fd corresponding to new connection to kernel space which in its turn
acts as server for
each new client.
So nfsd (and all COTS related nfs_tbind code) only accepts new
connections giving
kernel a chance to make all other communication related work.

If so, probably this way is appropriate for lockd with ticotsord
provider, because ticotsord is
used as direct communication channel between lockd itself and kernel space.

>
>
>>
>> Both nfsd and lockd calls do_one function and pass svc callback to it.
>> In case of lockd svc callback
>> is nlmsvc function which calls LM_SVC nfs syscall that opens in its
>> turn makes kernel to register
>> kRPC server handles for given protocols and devices. By some reason
>
> ...
>
>> In case of nfsd do_one function calls nfssvc callback for CLTS only.
>> nfssvc calls NFS_SVC nfssys
>> that in its turn creates kRPC server handle. According to the code,
>> nfs_tbind.c will create only CLTS
>> kRPC server handles for nfsd. Is it right?
>
>
>
> 1. For udp it will be called at once from do_one()
>
> 2. For tcp it delays until incoming connection arrives. For nfsd see to
>
>
> *** src/cmd/fs.d/nfs/nfsd/nfsd.c:
>         int (*Mysvc)(int , struct netbuf, struct netconfig *) = nfssvc;
>
> *** src/cmd/fs.d/nfs/lib/nfs_tbind.c:
> cots_listen_event[1425]        ret = (*Mysvc)(new_fd, addrmask, nconf);
>
>
>
>



-- 
W.B.R.
Dan Kruchinin