Subject: Re: [PATCH v2 net-next 2/7] octeontx2-pf: Handle VF function level reset

From: Leon Romanovsky <[email-masked]>
Date: Fri, 13 Mar 2020 20:16:48 +0200

On Fri, Mar 13, 2020 at 03:12:41PM +0530, [email-masked] wrote:
> From: Geetha sowjanya <[email-masked]>
>
> When FLR is initiated for a VF (PCI function level reset),
> the parent PF gets a interrupt. PF then sends a message to
> admin function (AF), which then cleanups all resources attached
> to that VF.
>
> Also handled IRQs triggered when master enable bit is cleared
> or set for VFs. This handler just clears the transaction pending
> ie TRPEND bit.
>
> Signed-off-by: Geetha sowjanya <[email-masked]>
> Signed-off-by: Sunil Goutham <[email-masked]>
> ---
>  .../ethernet/marvell/octeontx2/nic/otx2_common.h   |   7 +
>  .../net/ethernet/marvell/octeontx2/nic/otx2_pf.c   | 234 ++++++++++++++++++++-
>  2 files changed, 240 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
> index 74439e1..c0a9693 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
> @@ -191,6 +191,11 @@ struct otx2_hw {
>  	u64			cgx_tx_stats[CGX_TX_STATS_COUNT];
>  };
>
> +struct flr_work {
> +	struct work_struct work;
> +	struct otx2_nic *pf;
> +};
> +
>  struct refill_work {
>  	struct delayed_work pool_refill_work;
>  	struct otx2_nic *pf;
> @@ -226,6 +231,8 @@ struct otx2_nic {
>
>  	u64			reset_count;
>  	struct work_struct	reset_task;
> +	struct workqueue_struct	*flr_wq;
> +	struct flr_work		*flr_wrk;
>  	struct refill_work	*refill_wrk;
>
>  	/* Ethtool stuff */
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> index 967ef7b..bf6e2529 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> @@ -61,6 +61,224 @@ static int otx2_change_mtu(struct net_device *netdev, int new_mtu)
>  	return err;
>  }
>
> +static void otx2_disable_flr_me_intr(struct otx2_nic *pf)
> +{
> +	int irq, vfs = pf->total_vfs;
> +
> +	/* Disable VFs ME interrupts */
> +	otx2_write64(pf, RVU_PF_VFME_INT_ENA_W1CX(0), INTR_MASK(vfs));
> +	irq = pci_irq_vector(pf->pdev, RVU_PF_INT_VEC_VFME0);
> +	free_irq(irq, pf);
> +
> +	/* Disable VFs FLR interrupts */
> +	otx2_write64(pf, RVU_PF_VFFLR_INT_ENA_W1CX(0), INTR_MASK(vfs));
> +	irq = pci_irq_vector(pf->pdev, RVU_PF_INT_VEC_VFFLR0);
> +	free_irq(irq, pf);
> +
> +	if (vfs <= 64)
> +		return;
> +
> +	otx2_write64(pf, RVU_PF_VFME_INT_ENA_W1CX(1), INTR_MASK(vfs - 64));
> +	irq = pci_irq_vector(pf->pdev, RVU_PF_INT_VEC_VFME1);
> +	free_irq(irq, pf);
> +
> +	otx2_write64(pf, RVU_PF_VFFLR_INT_ENA_W1CX(1), INTR_MASK(vfs - 64));
> +	irq = pci_irq_vector(pf->pdev, RVU_PF_INT_VEC_VFFLR1);
> +	free_irq(irq, pf);
> +}
> +
> +static void otx2_flr_wq_destroy(struct otx2_nic *pf)
> +{
> +	if (!pf->flr_wq)
> +		return;
> +	flush_workqueue(pf->flr_wq);
> +	destroy_workqueue(pf->flr_wq);

destroy_workqueue() calls to drain_workqueue() which calls to
flush_workqueue() in proper order and not like it is written here.

> +	pf->flr_wq = NULL;
> +	devm_kfree(pf->dev, pf->flr_wrk);
> +}
> +
> +static void otx2_flr_handler(struct work_struct *work)
> +{
> +	struct flr_work *flrwork = container_of(work, struct flr_work, work);
> +	struct otx2_nic *pf = flrwork->pf;
> +	struct msg_req *req;
> +	int vf, reg = 0;
> +
> +	vf = flrwork - pf->flr_wrk;
> +
> +	otx2_mbox_lock(&pf->mbox);

It is so bad that such function exists, it hides simple mutex_lock()
which is standard primitive.

Thanks