Re: [PATCH 3/5] qedr: remove CQ spinlock from RDMA CM completion handlers

[Leon Romanovsky <leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

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On Mon, Jan 23, 2017 at 05:26:25PM +0200, Ram Amrani wrote:
> From: Ram Amrani <Ram.Amrani-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
>
> There is only a single event queue that triggers the completion
> events for the RDMA CM and it is being processed serially. This means
> that inherently there can no parallelism of CQ completion handler.
> Hence the lock is redundant.
>
> Signed-off-by: Ram Amrani <Ram.Amrani-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
> ---
>  drivers/infiniband/hw/qedr/qedr_cm.c | 10 ++--------
>  1 file changed, 2 insertions(+), 8 deletions(-)

Don't you need to remove this lock from struct qedr_cq too?

>
> diff --git a/drivers/infiniband/hw/qedr/qedr_cm.c b/drivers/infiniband/hw/qedr/qedr_cm.c
> index 63890eb..00361f3 100644
> --- a/drivers/infiniband/hw/qedr/qedr_cm.c
> +++ b/drivers/infiniband/hw/qedr/qedr_cm.c
> @@ -87,11 +87,8 @@ void qedr_ll2_tx_cb(void *_qdev, struct qed_roce_ll2_packet *pkt)
>  	qedr_inc_sw_gsi_cons(&qp->sq);
>  	spin_unlock_irqrestore(&qp->q_lock, flags);
>
> -	if (cq->ibcq.comp_handler) {
> -		spin_lock_irqsave(&cq->comp_handler_lock, flags);
> +	if (cq->ibcq.comp_handler)
>  		(*cq->ibcq.comp_handler) (&cq->ibcq, cq->ibcq.cq_context);
> -		spin_unlock_irqrestore(&cq->comp_handler_lock, flags);
> -	}
>  }
>
>  void qedr_ll2_rx_cb(void *_dev, struct qed_roce_ll2_packet *pkt,
> @@ -113,11 +110,8 @@ void qedr_ll2_rx_cb(void *_dev, struct qed_roce_ll2_packet *pkt,
>
>  	spin_unlock_irqrestore(&qp->q_lock, flags);
>
> -	if (cq->ibcq.comp_handler) {
> -		spin_lock_irqsave(&cq->comp_handler_lock, flags);
> +	if (cq->ibcq.comp_handler)
>  		(*cq->ibcq.comp_handler) (&cq->ibcq, cq->ibcq.cq_context);
> -		spin_unlock_irqrestore(&cq->comp_handler_lock, flags);
> -	}
>  }
>
>  static void qedr_destroy_gsi_cq(struct qedr_dev *dev,
> --
> 1.8.3.1
>
> --
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