On Mon, May 07, 2018 at 03:27:37PM -0400, Chuck Lever wrote: > Rather than releasing the incoming svc_rdma_recv_ctxt at the end of > svc_rdma_recvfrom, hold onto it until svc_rdma_sendto. > > This permits the contents of the Receive buffer to be preserved > through svc_process and then referenced directly in sendto as it > constructs Write and Reply chunks to return to the client. > > The real changes will come in subsequent patches. > > Note: I cannot use ->xpo_release_rqst for this purpose because that > is called _before_ ->xpo_sendto. svc_rdma_sendto uses information in > the received Call transport header to construct the Reply transport > header, which is preserved in the RPC's Receive buffer. > > The historical comment in svc_send() isn't helpful: it is already > obvious that ->xpo_release_rqst is being called before ->xpo_sendto, > but there is no explanation for this ordering going back to the > beginning of the git era. Yeah. I'm fine with deleting that comment at least. (Or maybe moving the call if it makes sense, I haven't thought about it.) --b. > > Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> > --- > net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 2 +- > net/sunrpc/xprtrdma/svc_rdma_sendto.c | 14 +++++++++++--- > 2 files changed, 12 insertions(+), 4 deletions(-) > > diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > index ecfe7c9..d9fef52 100644 > --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > @@ -789,7 +789,7 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp) > goto out_readchunk; > > complete: > - svc_rdma_recv_ctxt_put(rdma_xprt, ctxt); > + rqstp->rq_xprt_ctxt = ctxt; > rqstp->rq_prot = IPPROTO_MAX; > svc_xprt_copy_addrs(rqstp, xprt); > return rqstp->rq_arg.len; > diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c > index a397d9a..cbbde70 100644 > --- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c > +++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c > @@ -623,6 +623,7 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) > struct svc_xprt *xprt = rqstp->rq_xprt; > struct svcxprt_rdma *rdma = > container_of(xprt, struct svcxprt_rdma, sc_xprt); > + struct svc_rdma_recv_ctxt *rctxt = rqstp->rq_xprt_ctxt; > __be32 *p, *rdma_argp, *rdma_resp, *wr_lst, *rp_ch; > struct xdr_buf *xdr = &rqstp->rq_res; > struct page *res_page; > @@ -675,7 +676,12 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) > wr_lst, rp_ch); > if (ret < 0) > goto err0; > - return 0; > + ret = 0; > + > +out: > + rqstp->rq_xprt_ctxt = NULL; > + svc_rdma_recv_ctxt_put(rdma, rctxt); > + return ret; > > err2: > if (ret != -E2BIG && ret != -EINVAL) > @@ -684,12 +690,14 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) > ret = svc_rdma_send_error_msg(rdma, rdma_resp, rqstp); > if (ret < 0) > goto err0; > - return 0; > + ret = 0; > + goto out; > > err1: > put_page(res_page); > err0: > trace_svcrdma_send_failed(rqstp, ret); > set_bit(XPT_CLOSE, &xprt->xpt_flags); > - return -ENOTCONN; > + ret = -ENOTCONN; > + goto out; > } -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
