On Fri, Mar 19, 2021 at 10:31:35AM -0400, Chuck Lever wrote:
> Introduce a server-side mechanism similar to commit e340c2d6ef2a
> ("xprtrdma: Reduce the doorbell rate (Receive)") to post Receive
> WRs in batch. It's first consumer is svc_rdma_post_recvs().
s/It's/Its'/.
Patches look OK to me.--b.
>
> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
> ---
> net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 56 +++++++++++++++++++++++--------
> 1 file changed, 42 insertions(+), 14 deletions(-)
>
> diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
> index 04148a656b2a..0c6aa8693f20 100644
> --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
> +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
> @@ -264,6 +264,47 @@ void svc_rdma_release_rqst(struct svc_rqst *rqstp)
> svc_rdma_recv_ctxt_put(rdma, ctxt);
> }
>
> +static bool svc_rdma_refresh_recvs(struct svcxprt_rdma *rdma,
> + unsigned int wanted, bool temp)
> +{
> + const struct ib_recv_wr *bad_wr = NULL;
> + struct svc_rdma_recv_ctxt *ctxt;
> + struct ib_recv_wr *recv_chain;
> + int ret;
> +
> + if (test_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags))
> + return false;
> +
> + recv_chain = NULL;
> + while (wanted--) {
> + ctxt = svc_rdma_recv_ctxt_get(rdma);
> + if (!ctxt)
> + break;
> +
> + trace_svcrdma_post_recv(ctxt);
> + ctxt->rc_temp = temp;
> + ctxt->rc_recv_wr.next = recv_chain;
> + recv_chain = &ctxt->rc_recv_wr;
> + }
> + if (!recv_chain)
> + return false;
> +
> + ret = ib_post_recv(rdma->sc_qp, recv_chain, &bad_wr);
> + if (ret)
> + goto err_free;
> + return true;
> +
> +err_free:
> + trace_svcrdma_rq_post_err(rdma, ret);
> + while (bad_wr) {
> + ctxt = container_of(bad_wr, struct svc_rdma_recv_ctxt,
> + rc_recv_wr);
> + bad_wr = bad_wr->next;
> + svc_rdma_recv_ctxt_put(rdma, ctxt);
> + }
> + return false;
> +}
> +
> static int __svc_rdma_post_recv(struct svcxprt_rdma *rdma,
> struct svc_rdma_recv_ctxt *ctxt)
> {
> @@ -301,20 +342,7 @@ static int svc_rdma_post_recv(struct svcxprt_rdma *rdma)
> */
> bool svc_rdma_post_recvs(struct svcxprt_rdma *rdma)
> {
> - struct svc_rdma_recv_ctxt *ctxt;
> - unsigned int i;
> - int ret;
> -
> - for (i = 0; i < rdma->sc_max_requests; i++) {
> - ctxt = svc_rdma_recv_ctxt_get(rdma);
> - if (!ctxt)
> - return false;
> - ctxt->rc_temp = true;
> - ret = __svc_rdma_post_recv(rdma, ctxt);
> - if (ret)
> - return false;
> - }
> - return true;
> + return svc_rdma_refresh_recvs(rdma, rdma->sc_max_requests, true);
> }
>
> /**
>
