Commit cf73fb2f authored by Seth Howell's avatar Seth Howell Committed by Jim Harris
Browse files

nvmf/rdma: add a pool of request_data structs 



This change is related to enabling multi-sgl element support in
the NVMe-oF target.

For single SGL use cases, there is a 1:1  relationship between
rdma_requests and ibv_wrs used to transfer the data associated with
the request. In the ingle SGL case that ibv_wr is embedded inside of
the spdk_nvmf_rdma_request structure as part of an rdma_request_data
structure.
However, with Multi-SGL element support, we require multiple
ibv_wrs per rdma_request. Insted of embedding these
structures inside of the rdma_request and bloating up that object, I
opted to leave the first one embedded in the object and create a pool
that requests can pull from in the Multi-SGL path.
By leaving the first request_data object embedded in the rdma_request
structure, we avoid adding the latency of requesting a mempool object
in the basic cases.

Change-Id: I7282242f1e34a32eb59b55f326a6c331d455625e
Signed-off-by: default avatarSeth Howell <seth.howell@intel.com>
Reviewed-on: https://review.gerrithub.io/c/428561


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
parent 3c88819b

lib/nvmf/rdma.c

+31 −6
Original line number Diff line number Diff line
@@ -211,6 +211,13 @@ struct spdk_nvmf_rdma_recv { 
	TAILQ_ENTRY(spdk_nvmf_rdma_recv) link;

};



struct spdk_nvmf_rdma_request_data {

	struct spdk_nvmf_rdma_wr	rdma_wr;

	struct ibv_send_wr		wr;

	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];

	void				*buffers[SPDK_NVMF_MAX_SGL_ENTRIES];

};



struct spdk_nvmf_rdma_request {

	struct spdk_nvmf_request		req;

	bool					data_from_pool;
@@ -225,12 +232,7 @@ struct spdk_nvmf_rdma_request { 
		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];

	} rsp;



	struct {

		struct spdk_nvmf_rdma_wr	rdma_wr;

		struct ibv_send_wr		wr;

		struct ibv_sge			sgl[NVMF_DEFAULT_TX_SGE];

		void				*buffers[NVMF_DEFAULT_TX_SGE];

	} data;

	struct spdk_nvmf_rdma_request_data	data;



	struct spdk_nvmf_rdma_wr		rdma_wr;
@@ -364,6 +366,8 @@ struct spdk_nvmf_rdma_transport { 


	struct rdma_event_channel	*event_channel;



	struct spdk_mempool		*data_wr_pool;



	pthread_mutex_t			lock;



	/* fields used to poll RDMA/IB events */
@@ -1712,6 +1716,17 @@ spdk_nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts) 
		return NULL;

	}



	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",

				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,

				   sizeof(struct spdk_nvmf_rdma_request_data),

				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,

				   SPDK_ENV_SOCKET_ID_ANY);

	if (!rtransport->data_wr_pool) {

		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");

		spdk_nvmf_rdma_destroy(&rtransport->transport);

		return NULL;

	}



	contexts = rdma_get_devices(NULL);

	if (contexts == NULL) {

		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
@@ -1850,6 +1865,16 @@ spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport) 
		free(device);

	}



	if (rtransport->data_wr_pool != NULL) {

		if (spdk_mempool_count(rtransport->data_wr_pool) !=

		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {

			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",

				    spdk_mempool_count(rtransport->data_wr_pool),

				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);

		}

	}



	spdk_mempool_free(rtransport->data_wr_pool);

	spdk_io_device_unregister(rtransport, NULL);

	pthread_mutex_destroy(&rtransport->lock);

	free(rtransport);