[RFC] After nfs restart, locks can't be recovered which record by lockd before

[Mi Jinlong <mijinlong@cn.fujitsu.com>]

Hi,

When testing the nfs's lock at NFSv3, I get a problem.
So I want someone help me, thanks!

Test Process:
  Step1, ClientA get an exclusive lock success.
  Step2, Using command "service nfs restart" to restart server's nfs se=
rvice.
  Step3. ClientB get lock should fail, but success.

I think after step2 (nfs service restart), clientA's lock should be rec=
overed.
But like above, clientA's lock doesn=E2=80=99t be recovered.

When tracing the kernel, I find nfsd will cause lockd stop when it stop=
=2E
When lockd stop, all locks will be release which is record before at lo=
ckd.

When nfsd start, the lockd will start also, but the statd don't know wh=
at happened
 at kernel, so after that, locks will be lost.

Is it right when nfs stop, the lockd will stop too?=20
If it's right, should locks be recovered after lockd start?

thanks,
Mi Jinlong