From: Kalesh AP <kalesh-anakkur.purayil@xxxxxxxxxxxx>
There are few use cases where CQ create and destroy
is seen before re-creating the CQ, this kind of use
case is disturbing the RR distribution and all the
active CQ getting mapped to only 2 NQ alternatively.
Fixing the CQ to NQ hash calculation by implementing
a quick load sorting mechanism under a mutex.
Using this, if the CQ was allocated and destroyed
before using it, the nq selecting algorithm still
obtains the least loaded CQ. Thus balancing the load
on NQs.
Signed-off-by: Selvin Xavier <selvin.xavier@xxxxxxxxxxxx>
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@xxxxxxxxxxxx>
---
drivers/infiniband/hw/bnxt_re/bnxt_re.h | 2 ++
drivers/infiniband/hw/bnxt_re/ib_verbs.c | 33 +++++++++++++++++++++++++-------
drivers/infiniband/hw/bnxt_re/main.c | 2 ++
drivers/infiniband/hw/bnxt_re/qplib_fp.c | 1 +
drivers/infiniband/hw/bnxt_re/qplib_fp.h | 1 +
5 files changed, 32 insertions(+), 7 deletions(-)
diff --git a/drivers/infiniband/hw/bnxt_re/bnxt_re.h b/drivers/infiniband/hw/bnxt_re/bnxt_re.h
index d1c839e..5f64fc4 100644
--- a/drivers/infiniband/hw/bnxt_re/bnxt_re.h
+++ b/drivers/infiniband/hw/bnxt_re/bnxt_re.h
@@ -159,6 +159,8 @@ struct bnxt_re_pacing {
struct bnxt_re_nq_record {
struct bnxt_qplib_nq nq[BNXT_RE_MAX_MSIX];
int num_msix;
+ /* serialize NQ access */
+ struct mutex load_lock;
};
#define MAX_CQ_HASH_BITS (16)
diff --git a/drivers/infiniband/hw/bnxt_re/ib_verbs.c b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
index a9c32c0..9b0a435 100644
--- a/drivers/infiniband/hw/bnxt_re/ib_verbs.c
+++ b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
@@ -3029,6 +3029,28 @@ int bnxt_re_post_recv(struct ib_qp *ib_qp, const struct ib_recv_wr *wr,
return rc;
}
+static struct bnxt_qplib_nq *bnxt_re_get_nq(struct bnxt_re_dev *rdev)
+{
+ int min, indx;
+
+ mutex_lock(&rdev->nqr->load_lock);
+ for (indx = 0, min = 0; indx < (rdev->nqr->num_msix - 1); indx++) {
+ if (rdev->nqr->nq[min].load > rdev->nqr->nq[indx].load)
+ min = indx;
+ }
+ rdev->nqr->nq[min].load++;
+ mutex_unlock(&rdev->nqr->load_lock);
+
+ return &rdev->nqr->nq[min];
+}
+
+static void bnxt_re_put_nq(struct bnxt_re_dev *rdev, struct bnxt_qplib_nq *nq)
+{
+ mutex_lock(&rdev->nqr->load_lock);
+ nq->load--;
+ mutex_unlock(&rdev->nqr->load_lock);
+}
+
/* Completion Queues */
int bnxt_re_destroy_cq(struct ib_cq *ib_cq, struct ib_udata *udata)
{
@@ -3047,6 +3069,8 @@ int bnxt_re_destroy_cq(struct ib_cq *ib_cq, struct ib_udata *udata)
hash_del(&cq->hash_entry);
}
bnxt_qplib_destroy_cq(&rdev->qplib_res, &cq->qplib_cq);
+
+ bnxt_re_put_nq(rdev, nq);
ib_umem_release(cq->umem);
atomic_dec(&rdev->stats.res.cq_count);
@@ -3065,8 +3089,6 @@ int bnxt_re_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
rdma_udata_to_drv_context(udata, struct bnxt_re_ucontext, ib_uctx);
struct bnxt_qplib_dev_attr *dev_attr = &rdev->dev_attr;
struct bnxt_qplib_chip_ctx *cctx;
- struct bnxt_qplib_nq *nq = NULL;
- unsigned int nq_alloc_cnt;
int cqe = attr->cqe;
int rc, entries;
u32 active_cqs;
@@ -3121,12 +3143,10 @@ int bnxt_re_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
* Allocating the NQ in a round robin fashion. nq_alloc_cnt is a
* used for getting the NQ index.
*/
- nq_alloc_cnt = atomic_inc_return(&rdev->nq_alloc_cnt);
- nq = &rdev->nqr->nq[nq_alloc_cnt % (rdev->nqr->num_msix - 1)];
cq->qplib_cq.max_wqe = entries;
- cq->qplib_cq.cnq_hw_ring_id = nq->ring_id;
- cq->qplib_cq.nq = nq;
cq->qplib_cq.coalescing = &rdev->cq_coalescing;
+ cq->qplib_cq.nq = bnxt_re_get_nq(rdev);
+ cq->qplib_cq.cnq_hw_ring_id = cq->qplib_cq.nq->ring_id;
rc = bnxt_qplib_create_cq(&rdev->qplib_res, &cq->qplib_cq);
if (rc) {
@@ -3136,7 +3156,6 @@ int bnxt_re_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
cq->ib_cq.cqe = entries;
cq->cq_period = cq->qplib_cq.period;
- nq->budget++;
active_cqs = atomic_inc_return(&rdev->stats.res.cq_count);
if (active_cqs > rdev->stats.res.cq_watermark)
diff --git a/drivers/infiniband/hw/bnxt_re/main.c b/drivers/infiniband/hw/bnxt_re/main.c
index 9acc0e2..e556110 100644
--- a/drivers/infiniband/hw/bnxt_re/main.c
+++ b/drivers/infiniband/hw/bnxt_re/main.c
@@ -1566,6 +1566,8 @@ static int bnxt_re_init_res(struct bnxt_re_dev *rdev)
bnxt_qplib_init_res(&rdev->qplib_res);
+ mutex_init(&rdev->nqr->load_lock);
+
for (i = 1; i < rdev->nqr->num_msix ; i++) {
db_offt = rdev->en_dev->msix_entries[i].db_offset;
rc = bnxt_qplib_enable_nq(rdev->en_dev->pdev, &rdev->nqr->nq[i - 1],
diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.c b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
index e2eea71..e56f42f 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
@@ -551,6 +551,7 @@ int bnxt_qplib_enable_nq(struct pci_dev *pdev, struct bnxt_qplib_nq *nq,
nq->pdev = pdev;
nq->cqn_handler = cqn_handler;
nq->srqn_handler = srqn_handler;
+ nq->load = 0;
/* Have a task to schedule CQ notifiers in post send case */
nq->cqn_wq = create_singlethread_workqueue("bnxt_qplib_nq");
diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.h b/drivers/infiniband/hw/bnxt_re/qplib_fp.h
index b5a90581..8ff56d7 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.h
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.h
@@ -519,6 +519,7 @@ struct bnxt_qplib_nq {
struct tasklet_struct nq_tasklet;
bool requested;
int budget;
+ u32 load;
cqn_handler_t cqn_handler;
srqn_handler_t srqn_handler;
--
2.5.5
