Hello Jisheng,
On Thu, 29 Mar 2018 18:15:36 +0800, Jisheng Zhang wrote:
> Current suspend/resume implementation reuses the mvneta_open() and
> mvneta_close(), but it could be optimized to take only necessary
> actions during suspend/resume.
>
> One obvious problem of current implementation is: after hundreds of
> system suspend/resume cycles, the resume of mvneta could fail due to
> fragmented dma coherent memory. After this patch, the non-necessary
> memory alloc/free is optimized out.
Indeed, this needs to be fixed, you're totally right.
> Signed-off-by: Jisheng Zhang <jisheng.zh...@synaptics.com>
> ---
> drivers/net/ethernet/marvell/mvneta.c | 76
> ++++++++++++++++++++++++++++++-----
> 1 file changed, 66 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c
> b/drivers/net/ethernet/marvell/mvneta.c
> index 4ec69bbd1eb4..1870f1dd7093 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -4575,14 +4575,46 @@ static int mvneta_remove(struct platform_device *pdev)
> #ifdef CONFIG_PM_SLEEP
> static int mvneta_suspend(struct device *device)
> {
> + int queue;
> struct net_device *dev = dev_get_drvdata(device);
> struct mvneta_port *pp = netdev_priv(dev);
>
> - rtnl_lock();
> - if (netif_running(dev))
> - mvneta_stop(dev);
> - rtnl_unlock();
> + if (!netif_running(dev))
> + return 0;
This is changing the behavior I believe. The current code is:
rtnl_lock();
if (netif_running(dev))
mvneta_stop(dev);
rtnl_unlock();
netif_device_detach(dev);
clk_disable_unprepare(pp->clk_bus);
clk_disable_unprepare(pp->clk);
return 0;
So, when netif_running(dev) is false, we're indeed not calling
mvneta_stop(), but we're still doing netif_device_detach(), and
disabling the clocks. With your change, we're no longer doing these
steps.
> +
> netif_device_detach(dev);
> +
> + mvneta_stop_dev(pp);
> +
> + if (!pp->neta_armada3700) {
> + spin_lock(&pp->lock);
> + pp->is_stopped = true;
> + spin_unlock(&pp->lock);
Real question: is it OK to set pp->is_stopped *after* calling
mvneta_stop_dev(), while it was set before calling mvneta_stop_dev() in
the current code ?
> +
> + cpuhp_state_remove_instance_nocalls(online_hpstate,
> + &pp->node_online);
> + cpuhp_state_remove_instance_nocalls(CPUHP_NET_MVNETA_DEAD,
> + &pp->node_dead);
Do we need to remove/add those CPU notifiers when suspending/resuming ?
> + }
> +
> + for (queue = 0; queue < rxq_number; queue++) {
> + struct mvneta_rx_queue *rxq = &pp->rxqs[queue];
> +
> + mvneta_rxq_drop_pkts(pp, rxq);
> + }
Wouldn't it make sense to have
mvneta_rxq_sw_deinit/mvneta_rxq_hw_deinit(), like you did for the
initialization ?
> +
> + for (queue = 0; queue < txq_number; queue++) {
> + struct mvneta_tx_queue *txq = &pp->txqs[queue];
> +
> + /* Set minimum bandwidth for disabled TXQs */
> + mvreg_write(pp, MVETH_TXQ_TOKEN_CFG_REG(txq->id), 0);
> + mvreg_write(pp, MVETH_TXQ_TOKEN_COUNT_REG(txq->id), 0);
> +
> + /* Set Tx descriptors queue starting address and size */
> + mvreg_write(pp, MVNETA_TXQ_BASE_ADDR_REG(txq->id), 0);
> + mvreg_write(pp, MVNETA_TXQ_SIZE_REG(txq->id), 0);
> + }
Same comment here: a mvneta_txq_sw_deinit()/mvneta_txq_hw_deinit()
would be good, and would avoid duplicating this logic.
> +
> clk_disable_unprepare(pp->clk_bus);
> clk_disable_unprepare(pp->clk);
> return 0;
> @@ -4593,7 +4625,7 @@ static int mvneta_resume(struct device *device)
> struct platform_device *pdev = to_platform_device(device);
> struct net_device *dev = dev_get_drvdata(device);
> struct mvneta_port *pp = netdev_priv(dev);
> - int err;
> + int err, queue;
>
> clk_prepare_enable(pp->clk);
> if (!IS_ERR(pp->clk_bus))
> @@ -4614,13 +4646,37 @@ static int mvneta_resume(struct device *device)
> return err;
> }
>
> + if (!netif_running(dev))
> + return 0;
> +
> netif_device_attach(dev);
> - rtnl_lock();
> - if (netif_running(dev)) {
> - mvneta_open(dev);
> - mvneta_set_rx_mode(dev);
> +
> + for (queue = 0; queue < rxq_number; queue++) {
> + struct mvneta_rx_queue *rxq = &pp->rxqs[queue];
> +
> + rxq->next_desc_to_proc = 0;
> + mvneta_rxq_hw_init(pp, rxq);
> }
> - rtnl_unlock();
> +
> + for (queue = 0; queue < txq_number; queue++) {
> + struct mvneta_tx_queue *txq = &pp->txqs[queue];
> +
> + txq->next_desc_to_proc = 0;
> + mvneta_txq_hw_init(pp, txq);
> + }
> +
> + if (!pp->neta_armada3700) {
> + spin_lock(&pp->lock);
> + pp->is_stopped = false;
> + spin_unlock(&pp->lock);
> + cpuhp_state_add_instance_nocalls(online_hpstate,
> + &pp->node_online);
> + cpuhp_state_add_instance_nocalls(CPUHP_NET_MVNETA_DEAD,
> + &pp->node_dead);
> + }
> +
> + mvneta_set_rx_mode(dev);
> + mvneta_start_dev(pp);
Thanks!
Thomas
--
Thomas Petazzoni, CTO, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com
