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From:   Chuck Lever <chuck.lever@oracle.com>
To:     Timo Rothenpieler <timo@rothenpieler.org>
CC:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Olga Kornievskaia <aglo@umich.edu>,
        Dai Ngo <dai.ngo@oracle.com>
Subject: Re: [PATCH] svcrdma: disable timeouts on rdma backchannel
Thread-Topic: [PATCH] svcrdma: disable timeouts on rdma backchannel
Thread-Index: AQHXCXOTv6ms0S5nPkS/+o1NfiK5PqpnXOQA
Date:   Wed, 24 Feb 2021 14:18:18 +0000
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 <20210222233619.21568-1-timo@rothenpieler.org>
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> On Feb 22, 2021, at 6:36 PM, Timo Rothenpieler <timo@rothenpieler.org> wr=
ote:
>=20
> This brings it in line with the regular tcp backchannel, which also has
> all those timeouts disabled.
>=20
> Prevents the backchannel from timing out, getting some async operations
> like server side copying getting stuck indefinitely on the client side.
>=20
> Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>

Thanks for your patch! I've included it in the for-rc branch at

git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git


> ---
> Did the same testing with this applied than before, and could not
> observe it getting stuck, same as with the previous patch, which I
> removed before testing this one.
>=20
> This obviously still does not fix the issue of it being seemingly unable
> to reestablish the disconnected backchannel.
> An event that disconnects the backchannel but leaves the main connection
> intact seems a pretty rare occurance though, outside of this issue.
>=20
> net/sunrpc/xprtrdma/svc_rdma_backchannel.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>=20
> diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprt=
rdma/svc_rdma_backchannel.c
> index 63f8be974df2..8186ab6f99f1 100644
> --- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
> +++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
> @@ -252,9 +252,9 @@ xprt_setup_rdma_bc(struct xprt_create *args)
> 	xprt->timeout =3D &xprt_rdma_bc_timeout;
> 	xprt_set_bound(xprt);
> 	xprt_set_connected(xprt);
> -	xprt->bind_timeout =3D RPCRDMA_BIND_TO;
> -	xprt->reestablish_timeout =3D RPCRDMA_INIT_REEST_TO;
> -	xprt->idle_timeout =3D RPCRDMA_IDLE_DISC_TO;
> +	xprt->bind_timeout =3D 0;
> +	xprt->reestablish_timeout =3D 0;
> +	xprt->idle_timeout =3D 0;
>=20
> 	xprt->prot =3D XPRT_TRANSPORT_BC_RDMA;
> 	xprt->ops =3D &xprt_rdma_bc_procs;
> --=20
> 2.25.1
>=20

--
Chuck Lever