Commit 653496d2 authored by Alexey Marchuk's avatar Alexey Marchuk Committed by Tomasz Zawadzki
Browse files

rdma: Calculate and allocate the number of WRs required to process the request 



RDMA WR has a predefined number of SGL entries (16) and with new logic added to
support DIF the number of entries required to process the request may exceed
this limit since IO unit buffers might be divided into several parts to remove
metadata chunks from the transmition. This change calculates and allocates
required number of WRs.
Error handling section in spdk_nvmf_rdma_request_fill_iovs has been updated
to free allocated WRs

Change-Id: Ie5d659d8305a454949827d1f4aff6d871b7e825d
Signed-off-by: default avatarAlexey Marchuk <alexeymar@mellanox.com>
Signed-off-by: default avatarSasha Kotchubievsky <sashakot@mellanox.com>
Signed-off-by: default avatarEvgenii Kochetov <evgeniik@mellanox.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/470474


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
parent 838c45c8

lib/nvmf/rdma.c

+36 −4
Original line number Diff line number Diff line
@@ -1665,6 +1665,27 @@ nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup, 
	return 0;

}



static inline uint32_t

nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)

{

	/* estimate the number of SG entries and WRs needed to process the request */

	uint32_t num_sge = 0;

	uint32_t i;

	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);



	for (i = 0; i < num_buffers && length > 0; i++) {

		uint32_t buffer_len = spdk_min(length, io_unit_size);

		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);



		if (num_sge_in_block * block_size > buffer_len) {

			++num_sge_in_block;

		}

		num_sge += num_sge_in_block;

		length -= buffer_len;

	}

	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);

}



static int

spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,

				 struct spdk_nvmf_rdma_device *device,
@@ -1676,6 +1697,7 @@ spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport, 
	struct spdk_nvmf_request		*req = &rdma_req->req;

	struct ibv_send_wr			*wr = &rdma_req->data.wr;

	int					rc;

	uint32_t				num_wrs = 1;



	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);

	rgroup = rqpair->poller->group;
@@ -1693,20 +1715,30 @@ spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport, 


	rdma_req->iovpos = 0;



	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length);

	if (spdk_unlikely(req->dif.dif_insert_or_strip)) {

		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,

						 req->dif.dif_ctx.block_size);

		if (num_wrs > 1) {

			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);

			if (rc != 0) {

				goto err_exit;

			}

		}

	}



	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length);

	if (spdk_unlikely(rc != 0)) {

		goto err_exit;

	}



	/* set the number of outstanding data WRs for this request. */

	rdma_req->num_outstanding_data_wr = 1;

	rdma_req->num_outstanding_data_wr = num_wrs;



	return rc;



err_exit:

	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);

	memset(wr->sg_list, 0, sizeof(wr->sg_list[0]) * wr->num_sge);

	wr->num_sge = 0;

	nvmf_rdma_request_free_data(rdma_req, rtransport);

	req->iovcnt = 0;

	return rc;

}