Commit 87a7f321 authored by John Fraker's avatar John Fraker Committed by David S. Miller
Browse files

gve: Recover from queue stall due to missed IRQ 



Don't always reset the driver on a TX timeout. Attempt to
recover by kicking the queue in case an IRQ was missed.

Fixes: 9e5f7d26 ("gve: Add workqueue and reset support")
Signed-off-by: default avatarJohn Fraker <jfraker@google.com>
Signed-off-by: default avatarDavid Awogbemila <awogbemila@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 61d72c7e

drivers/net/ethernet/google/gve/gve.h

+3 −1
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ 
#define GVE_MIN_MSIX 3



/* Numbers of gve tx/rx stats in stats report. */

#define GVE_TX_STATS_REPORT_NUM	5

#define GVE_TX_STATS_REPORT_NUM	6

#define GVE_RX_STATS_REPORT_NUM	2



/* Interval to schedule a stats report update, 20000ms. */
@@ -413,7 +413,9 @@ struct gve_tx_ring { 
	u32 q_num ____cacheline_aligned; /* queue idx */

	u32 stop_queue; /* count of queue stops */

	u32 wake_queue; /* count of queue wakes */

	u32 queue_timeout; /* count of queue timeouts */

	u32 ntfy_id; /* notification block index */

	u32 last_kick_msec; /* Last time the queue was kicked */

	dma_addr_t bus; /* dma address of the descr ring */

	dma_addr_t q_resources_bus; /* dma address of the queue resources */

	dma_addr_t complq_bus_dqo; /* dma address of the dqo.compl_ring */

drivers/net/ethernet/google/gve/gve_adminq.h

+1 −0
Original line number Diff line number Diff line
@@ -270,6 +270,7 @@ enum gve_stat_names { 
	TX_LAST_COMPLETION_PROCESSED	= 5,

	RX_NEXT_EXPECTED_SEQUENCE	= 6,

	RX_BUFFERS_POSTED		= 7,

	TX_TIMEOUT_CNT			= 8,

	// stats from NIC

	RX_QUEUE_DROP_CNT		= 65,

	RX_NO_BUFFERS_POSTED		= 66,

drivers/net/ethernet/google/gve/gve_main.c

+47 −1
Original line number Diff line number Diff line
@@ -24,6 +24,9 @@ 
#define GVE_VERSION		"1.0.0"

#define GVE_VERSION_PREFIX	"GVE-"



// Minimum amount of time between queue kicks in msec (10 seconds)

#define MIN_TX_TIMEOUT_GAP (1000 * 10)



const char gve_version_str[] = GVE_VERSION;

static const char gve_version_prefix[] = GVE_VERSION_PREFIX;
@@ -1121,9 +1124,47 @@ static void gve_turnup(struct gve_priv *priv) 


static void gve_tx_timeout(struct net_device *dev, unsigned int txqueue)

{

	struct gve_priv *priv = netdev_priv(dev);

	struct gve_notify_block *block;

	struct gve_tx_ring *tx = NULL;

	struct gve_priv *priv;

	u32 last_nic_done;

	u32 current_time;

	u32 ntfy_idx;



	netdev_info(dev, "Timeout on tx queue, %d", txqueue);

	priv = netdev_priv(dev);

	if (txqueue > priv->tx_cfg.num_queues)

		goto reset;



	ntfy_idx = gve_tx_idx_to_ntfy(priv, txqueue);

	if (ntfy_idx > priv->num_ntfy_blks)

		goto reset;



	block = &priv->ntfy_blocks[ntfy_idx];

	tx = block->tx;



	current_time = jiffies_to_msecs(jiffies);

	if (tx->last_kick_msec + MIN_TX_TIMEOUT_GAP > current_time)

		goto reset;



	/* Check to see if there are missed completions, which will allow us to

	 * kick the queue.

	 */

	last_nic_done = gve_tx_load_event_counter(priv, tx);

	if (last_nic_done - tx->done) {

		netdev_info(dev, "Kicking queue %d", txqueue);

		iowrite32be(GVE_IRQ_MASK, gve_irq_doorbell(priv, block));

		napi_schedule(&block->napi);

		tx->last_kick_msec = current_time;

		goto out;

	} // Else reset.



reset:

	gve_schedule_reset(priv);



out:

	if (tx)

		tx->queue_timeout++;

	priv->tx_timeo_cnt++;

}
@@ -1252,6 +1293,11 @@ void gve_handle_report_stats(struct gve_priv *priv) 
				.value = cpu_to_be64(last_completion),

				.queue_id = cpu_to_be32(idx),

			};

			stats[stats_idx++] = (struct stats) {

				.stat_name = cpu_to_be32(TX_TIMEOUT_CNT),

				.value = cpu_to_be64(priv->tx[idx].queue_timeout),

				.queue_id = cpu_to_be32(idx),

			};

		}

	}

	/* rx stats */