> On Mar 22, 2021, at 1:16 PM, J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote:
>
> 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'/.
D'oh!
> Patches look OK to me.--b.
Thanks for the review!
>> 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);
>> }
>>
>> /**
>>
--
Chuck Lever
