Commit 6ddc9dea authored by Chuck Lever's avatar Chuck Lever Committed by Trond Myklebust
Browse files

SUNRPC: Fix backchannel reply, again 



I still see "RPC: Could not send backchannel reply error: -110"
quite often, along with slow-running tests. Debugging shows that the
backchannel is still stumbling when it has to queue a callback reply
on a busy transport.

Note that every one of these timeouts causes a connection loss by
virtue of the xprt_conditional_disconnect() call in that arm of
call_cb_transmit_status().

I found that setting to_maxval is necessary to get the RPC timeout
logic to behave whenever to_exponential is not set.

Fixes: 57331a59 ("NFSv4.1: Use the nfs_client's rpc timeouts for backchannel")
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Reviewed-by: default avatarBenjamin Coddington <bcodding@redhat.com>
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent 6ba59ff4

net/sunrpc/svc.c

+4 −1
Original line number Diff line number Diff line
@@ -1557,9 +1557,11 @@ void svc_process(struct svc_rqst *rqstp) 
 */

void svc_process_bc(struct rpc_rqst *req, struct svc_rqst *rqstp)

{

	struct rpc_timeout timeout = {

		.to_increment		= 0,

	};

	struct rpc_task *task;

	int proc_error;

	struct rpc_timeout timeout;



	/* Build the svc_rqst used by the common processing routine */

	rqstp->rq_xid = req->rq_xid;
@@ -1612,6 +1614,7 @@ void svc_process_bc(struct rpc_rqst *req, struct svc_rqst *rqstp) 
		timeout.to_initval = req->rq_xprt->timeout->to_initval;

		timeout.to_retries = req->rq_xprt->timeout->to_retries;

	}

	timeout.to_maxval = timeout.to_initval;

	memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf));

	task = rpc_run_bc_task(req, &timeout);