Commit c6e66307 authored by Yamin Friedman's avatar Yamin Friedman Committed by Jason Gunthorpe
Browse files

IB/isert: use new shared CQ mechanism 

Have the driver use shared CQs provided by the rdma core driver.  Since
this provides similar functionality to iser_comp it has been removed.

Now there is no reason to allocate very large CQs when the driver is
loaded while gaining the advantage of shared CQs. Previously when a single
connection was opened a CQ was opened for every core with enough space for
eight connections, this is a very large overhead that in most cases will
not be utilized.

Link: https://lore.kernel.org/r/20200722135629.49467-2-maxg@mellanox.com


Signed-off-by: default avatarYamin Friedman <yaminf@mellanox.com>
Signed-off-by: default avatarMax Gurtovoy <maxg@mellanox.com>
Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent d56a7852

drivers/infiniband/ulp/isert/ib_isert.c

+32 −137
Original line number Diff line number Diff line
@@ -24,13 +24,6 @@ 


#include "ib_isert.h"



#define	ISERT_MAX_CONN		8

#define ISER_MAX_RX_CQ_LEN	(ISERT_QP_MAX_RECV_DTOS * ISERT_MAX_CONN)

#define ISER_MAX_TX_CQ_LEN \

	((ISERT_QP_MAX_REQ_DTOS + ISCSI_DEF_XMIT_CMDS_MAX) * ISERT_MAX_CONN)

#define ISER_MAX_CQ_LEN		(ISER_MAX_RX_CQ_LEN + ISER_MAX_TX_CQ_LEN + \

				 ISERT_MAX_CONN)



static int isert_debug_level;

module_param_named(debug_level, isert_debug_level, int, 0644);

MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:0)");
@@ -82,50 +75,29 @@ isert_qp_event_callback(struct ib_event *e, void *context) 
	}

}



static struct isert_comp *

isert_comp_get(struct isert_conn *isert_conn)

{

	struct isert_device *device = isert_conn->device;

	struct isert_comp *comp;

	int i, min = 0;



	mutex_lock(&device_list_mutex);

	for (i = 0; i < device->comps_used; i++)

		if (device->comps[i].active_qps <

		    device->comps[min].active_qps)

			min = i;

	comp = &device->comps[min];

	comp->active_qps++;

	mutex_unlock(&device_list_mutex);



	isert_info("conn %p, using comp %p min_index: %d\n",

		   isert_conn, comp, min);



	return comp;

}



static void

isert_comp_put(struct isert_comp *comp)

{

	mutex_lock(&device_list_mutex);

	comp->active_qps--;

	mutex_unlock(&device_list_mutex);

}



static struct ib_qp *

isert_create_qp(struct isert_conn *isert_conn,

		struct isert_comp *comp,

		struct rdma_cm_id *cma_id)

{

	u32 cq_size = ISERT_QP_MAX_REQ_DTOS + ISERT_QP_MAX_RECV_DTOS + 2;

	struct isert_device *device = isert_conn->device;

	struct ib_device *ib_dev = device->ib_device;

	struct ib_qp_init_attr attr;

	int ret, factor;



	isert_conn->cq = ib_cq_pool_get(ib_dev, cq_size, -1, IB_POLL_WORKQUEUE);

	if (IS_ERR(isert_conn->cq)) {

		isert_err("Unable to allocate cq\n");

		ret = PTR_ERR(isert_conn->cq);

		return ERR_PTR(ret);

	}

	isert_conn->cq_size = cq_size;



	memset(&attr, 0, sizeof(struct ib_qp_init_attr));

	attr.event_handler = isert_qp_event_callback;

	attr.qp_context = isert_conn;

	attr.send_cq = comp->cq;

	attr.recv_cq = comp->cq;

	attr.send_cq = isert_conn->cq;

	attr.recv_cq = isert_conn->cq;

	attr.cap.max_send_wr = ISERT_QP_MAX_REQ_DTOS + 1;

	attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS + 1;

	factor = rdma_rw_mr_factor(device->ib_device, cma_id->port_num,
@@ -141,31 +113,14 @@ isert_create_qp(struct isert_conn *isert_conn, 
	ret = rdma_create_qp(cma_id, device->pd, &attr);

	if (ret) {

		isert_err("rdma_create_qp failed for cma_id %d\n", ret);

		ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);



		return ERR_PTR(ret);

	}



	return cma_id->qp;

}



static int

isert_conn_setup_qp(struct isert_conn *isert_conn, struct rdma_cm_id *cma_id)

{

	struct isert_comp *comp;

	int ret;



	comp = isert_comp_get(isert_conn);

	isert_conn->qp = isert_create_qp(isert_conn, comp, cma_id);

	if (IS_ERR(isert_conn->qp)) {

		ret = PTR_ERR(isert_conn->qp);

		goto err;

	}



	return 0;

err:

	isert_comp_put(comp);

	return ret;

}



static int

isert_alloc_rx_descriptors(struct isert_conn *isert_conn)

{
@@ -233,61 +188,6 @@ isert_free_rx_descriptors(struct isert_conn *isert_conn) 
	isert_conn->rx_descs = NULL;

}



static void

isert_free_comps(struct isert_device *device)

{

	int i;



	for (i = 0; i < device->comps_used; i++) {

		struct isert_comp *comp = &device->comps[i];



		if (comp->cq)

			ib_free_cq(comp->cq);

	}

	kfree(device->comps);

}



static int

isert_alloc_comps(struct isert_device *device)

{

	int i, max_cqe, ret = 0;



	device->comps_used = min(ISERT_MAX_CQ, min_t(int, num_online_cpus(),

				 device->ib_device->num_comp_vectors));



	isert_info("Using %d CQs, %s supports %d vectors support "

		   "pi_capable %d\n",

		   device->comps_used, dev_name(&device->ib_device->dev),

		   device->ib_device->num_comp_vectors,

		   device->pi_capable);



	device->comps = kcalloc(device->comps_used, sizeof(struct isert_comp),

				GFP_KERNEL);

	if (!device->comps)

		return -ENOMEM;



	max_cqe = min(ISER_MAX_CQ_LEN, device->ib_device->attrs.max_cqe);



	for (i = 0; i < device->comps_used; i++) {

		struct isert_comp *comp = &device->comps[i];



		comp->device = device;

		comp->cq = ib_alloc_cq(device->ib_device, comp, max_cqe, i,

				IB_POLL_WORKQUEUE);

		if (IS_ERR(comp->cq)) {

			isert_err("Unable to allocate cq\n");

			ret = PTR_ERR(comp->cq);

			comp->cq = NULL;

			goto out_cq;

		}

	}



	return 0;

out_cq:

	isert_free_comps(device);

	return ret;

}



static int

isert_create_device_ib_res(struct isert_device *device)

{
@@ -298,16 +198,12 @@ isert_create_device_ib_res(struct isert_device *device) 
		  ib_dev->attrs.max_send_sge, ib_dev->attrs.max_recv_sge);

	isert_dbg("devattr->max_sge_rd: %d\n", ib_dev->attrs.max_sge_rd);



	ret = isert_alloc_comps(device);

	if (ret)

		goto out;



	device->pd = ib_alloc_pd(ib_dev, 0);

	if (IS_ERR(device->pd)) {

		ret = PTR_ERR(device->pd);

		isert_err("failed to allocate pd, device %p, ret=%d\n",

			  device, ret);

		goto out_cq;

		return ret;

	}



	/* Check signature cap */
@@ -315,13 +211,6 @@ isert_create_device_ib_res(struct isert_device *device) 
			     IB_DEVICE_INTEGRITY_HANDOVER ? true : false;



	return 0;



out_cq:

	isert_free_comps(device);

out:

	if (ret > 0)

		ret = -EINVAL;

	return ret;

}



static void
@@ -330,7 +219,6 @@ isert_free_device_ib_res(struct isert_device *device) 
	isert_info("device %p\n", device);



	ib_dealloc_pd(device->pd);

	isert_free_comps(device);

}



static void
@@ -492,6 +380,13 @@ isert_set_nego_params(struct isert_conn *isert_conn, 
	}

}



static void

isert_destroy_qp(struct isert_conn *isert_conn)

{

	ib_destroy_qp(isert_conn->qp);

	ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);

}



static int

isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)

{
@@ -532,17 +427,19 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event) 


	isert_set_nego_params(isert_conn, &event->param.conn);



	ret = isert_conn_setup_qp(isert_conn, cma_id);

	if (ret)

	isert_conn->qp = isert_create_qp(isert_conn, cma_id);

	if (IS_ERR(isert_conn->qp)) {

		ret = PTR_ERR(isert_conn->qp);

		goto out_conn_dev;

	}



	ret = isert_login_post_recv(isert_conn);

	if (ret)

		goto out_conn_dev;

		goto out_destroy_qp;



	ret = isert_rdma_accept(isert_conn);

	if (ret)

		goto out_conn_dev;

		goto out_destroy_qp;



	mutex_lock(&isert_np->mutex);

	list_add_tail(&isert_conn->node, &isert_np->accepted);
@@ -550,6 +447,8 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event) 


	return 0;



out_destroy_qp:

	isert_destroy_qp(isert_conn);

out_conn_dev:

	isert_device_put(device);

out_rsp_dma_map:
@@ -574,12 +473,8 @@ isert_connect_release(struct isert_conn *isert_conn) 
	    !isert_conn->dev_removed)

		rdma_destroy_id(isert_conn->cm_id);



	if (isert_conn->qp) {

		struct isert_comp *comp = isert_conn->qp->recv_cq->cq_context;



		isert_comp_put(comp);

		ib_destroy_qp(isert_conn->qp);

	}

	if (isert_conn->qp)

		isert_destroy_qp(isert_conn);



	if (isert_conn->login_req_buf)

		isert_free_login_buf(isert_conn);

drivers/infiniband/ulp/isert/ib_isert.h

+2 −16
Original line number Diff line number Diff line
@@ -156,6 +156,8 @@ struct isert_conn { 
	struct iser_tx_desc	login_tx_desc;

	struct rdma_cm_id	*cm_id;

	struct ib_qp		*qp;

	struct ib_cq		*cq;

	u32			cq_size;

	struct isert_device	*device;

	struct mutex		mutex;

	struct kref		kref;
@@ -166,22 +168,6 @@ struct isert_conn { 
	bool			dev_removed;

};



#define ISERT_MAX_CQ 64



/**

 * struct isert_comp - iSER completion context

 *

 * @device:     pointer to device handle

 * @cq:         completion queue

 * @active_qps: Number of active QPs attached

 *              to completion context

 */

struct isert_comp {

	struct isert_device     *device;

	struct ib_cq		*cq;

	int                      active_qps;

};



struct isert_device {

	bool			pi_capable;

	int			refcount;

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