Re: [RFC PATCH 0/4] NFS: Fix another 'check_flush_dependency' splat

[Zhu Yanjun <zyjzyj2000@gmail.com>]

On 30.04.24 16:13, Chuck Lever III wrote:
> 
> 
>> On Apr 30, 2024, at 9:58 AM, Zhu Yanjun <yanjun.zhu@linux.dev> wrote:
>>
>>
>> On 30.04.24 15:42, Chuck Lever III wrote:
>>>
>>>> On Apr 30, 2024, at 3:26 AM, Zhu Yanjun <zyjzyj2000@gmail.com> wrote:
>>>>
>>>> On 29.04.24 17:25, cel@kernel.org wrote:
>>>>> From: Chuck Lever <chuck.lever@oracle.com>
>>>>> Avoid getting work queue splats in the system journal by moving
>>>>> client-side RPC/RDMA transport tear-down into a background process.
>>>>> I've done some testing of this series, now looking for review
>>>>> comments.
>>>> How to make tests with nfs && rdma? Can you provide some steps or tools?
>>> We are building NFS tests into kdevops:
>>>
>>>     https://github.com/linux-kdevops/kdevops.git
>>>
>>> and there is a config option to use soft iWARP instead of TCP.
>>
>> Thanks a lot. It is interesting. Have you made tests with RXE instead of iWARP?
>>
>> If yes, does nfs work well with RXE? I am just curious with nfs && RXE.
>>
>> Normally nfs works with TCP. Now nfs will use RDMA instead of TCP.
>>
>> The popular RDMA implementation is RoCEv2 which is based on UDP protocol.
>>
>> So I am curious if NFS can work well with RXE (RoCEv2 emulation driver) or not.
>>
>> If the user wants to use nfs in his production hosts, it is possible that nfs will work with RoCEv2 (UDP).
> 
> Yes, NFS/RDMA works with rxe and even with rxe mixed with
> hardware RoCE. Someone else will have to step in and say
> whether it works "well" since I don't use rxe, only CX-5
> and newer on 100GbE.
> 
> Generally we use siw because our testing environment varies
> between all systems on a single local network or hypervisor,
> all the way up to NFS/RDMA on VPN and WAN. The rxe driver
> doesn't support operation over tunnels, currently.

Thanks a lot. "The rxe driver doesn't support operation over tunnels, 
currently." Do you mean that rxe can not work well with tun/tap device?

> 
> It is possible to add rxe as a second option in kdevops,
> but siw has worked for our purposes so far, and the NFS
> test matrix is already enormous.

Thanks. If rxe can be as a second option in kdevops, I will make tests 
with kdevops to check rxe work well or not in the future kernel version.

Best Regards,
Zhu Yanjun

> 
> 
>> Best Regards,
>>
>> Zhu Yanjun
>>
>>> kdevops includes workflows for fstests, Mora's nfstest, the
>>> git regression suite, and ltp, all of which we use regularly
>>> to test the Linux NFS client and server implementations.
>>>
>>>
>>>> I am interested in nfs && rdma.
>>>>
>>>> Thanks,
>>>> Zhu Yanjun
>>>>
>>>>> Chuck Lever (4):
>>>>>    xprtrdma: Remove temp allocation of rpcrdma_rep objects
>>>>>    xprtrdma: Clean up synopsis of frwr_mr_unmap()
>>>>>    xprtrdma: Delay releasing connection hardware resources
>>>>>    xprtrdma: Move MRs to struct rpcrdma_ep
>>>>>   net/sunrpc/xprtrdma/frwr_ops.c  |  13 ++-
>>>>>   net/sunrpc/xprtrdma/rpc_rdma.c  |   3 +-
>>>>>   net/sunrpc/xprtrdma/transport.c |  20 +++-
>>>>>   net/sunrpc/xprtrdma/verbs.c     | 173 ++++++++++++++++----------------
>>>>>   net/sunrpc/xprtrdma/xprt_rdma.h |  21 ++--
>>>>>   5 files changed, 125 insertions(+), 105 deletions(-)
>>>>> base-commit: e67572cd2204894179d89bd7b984072f19313b03
>>> --
>>> Chuck Lever
>>>
>>>
>> -- 
>> Best Regards,
>> Yanjun.Zhu
> 
> 
> --
> Chuck Lever
> 
>