RDMA/qedr: SRQ's bug fixes

QP's with the same SRQ, working on different CQs and running in parallel
on different CPUs could lead to a race when maintaining the SRQ consumer
count, and leads to FW running out of SRQs. Update the consumer
atomically.  Make sure the wqe_prod is updated after the sge_prod due to
FW requirements.

Fixes: 3491c9e799 ("qedr: Add support for kernel mode SRQ's")
Link: https://lore.kernel.org/r/20200708195526.31040-1-ybason@marvell.com
Signed-off-by: Michal Kalderon <mkalderon@marvell.com>
Signed-off-by: Yuval Basson <ybason@marvell.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This commit is contained in:
Yuval Basson 2020-07-08 22:55:26 +03:00 committed by Jason Gunthorpe
parent 317000b926
commit acca72e2b0
2 changed files with 12 additions and 14 deletions

View File

@ -344,10 +344,10 @@ struct qedr_srq_hwq_info {
u32 wqe_prod;
u32 sge_prod;
u32 wr_prod_cnt;
u32 wr_cons_cnt;
atomic_t wr_cons_cnt;
u32 num_elems;
u32 *virt_prod_pair_addr;
struct rdma_srq_producers *virt_prod_pair_addr;
dma_addr_t phy_prod_pair_addr;
};

View File

@ -3686,7 +3686,7 @@ static u32 qedr_srq_elem_left(struct qedr_srq_hwq_info *hw_srq)
* count and consumer count and subtract it from max
* work request supported so that we get elements left.
*/
used = hw_srq->wr_prod_cnt - hw_srq->wr_cons_cnt;
used = hw_srq->wr_prod_cnt - (u32)atomic_read(&hw_srq->wr_cons_cnt);
return hw_srq->max_wr - used;
}
@ -3701,7 +3701,6 @@ int qedr_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
unsigned long flags;
int status = 0;
u32 num_sge;
u32 offset;
spin_lock_irqsave(&srq->lock, flags);
@ -3714,7 +3713,8 @@ int qedr_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
if (!qedr_srq_elem_left(hw_srq) ||
wr->num_sge > srq->hw_srq.max_sges) {
DP_ERR(dev, "Can't post WR (%d,%d) || (%d > %d)\n",
hw_srq->wr_prod_cnt, hw_srq->wr_cons_cnt,
hw_srq->wr_prod_cnt,
atomic_read(&hw_srq->wr_cons_cnt),
wr->num_sge, srq->hw_srq.max_sges);
status = -ENOMEM;
*bad_wr = wr;
@ -3748,22 +3748,20 @@ int qedr_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
hw_srq->sge_prod++;
}
/* Flush WQE and SGE information before
/* Update WQE and SGE information before
* updating producer.
*/
wmb();
dma_wmb();
/* SRQ producer is 8 bytes. Need to update SGE producer index
* in first 4 bytes and need to update WQE producer in
* next 4 bytes.
*/
*srq->hw_srq.virt_prod_pair_addr = hw_srq->sge_prod;
offset = offsetof(struct rdma_srq_producers, wqe_prod);
*((u8 *)srq->hw_srq.virt_prod_pair_addr + offset) =
hw_srq->wqe_prod;
srq->hw_srq.virt_prod_pair_addr->sge_prod = hw_srq->sge_prod;
/* Make sure sge producer is updated first */
dma_wmb();
srq->hw_srq.virt_prod_pair_addr->wqe_prod = hw_srq->wqe_prod;
/* Flush producer after updating it. */
wmb();
wr = wr->next;
}
@ -4182,7 +4180,7 @@ static int process_resp_one_srq(struct qedr_dev *dev, struct qedr_qp *qp,
} else {
__process_resp_one(dev, qp, cq, wc, resp, wr_id);
}
srq->hw_srq.wr_cons_cnt++;
atomic_inc(&srq->hw_srq.wr_cons_cnt);
return 1;
}