From 87a7f321bb6a45e54b7d6c90d032ee5636a6ad97 Mon Sep 17 00:00:00 2001 From: John Fraker Date: Mon, 11 Oct 2021 08:36:47 -0700 Subject: [PATCH] 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: 9e5f7d26a4c08 ("gve: Add workqueue and reset support") Signed-off-by: John Fraker Signed-off-by: David Awogbemila Signed-off-by: David S. Miller --- drivers/net/ethernet/google/gve/gve.h | 4 +- drivers/net/ethernet/google/gve/gve_adminq.h | 1 + drivers/net/ethernet/google/gve/gve_main.c | 48 +++++++++++++++++++- 3 files changed, 51 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h index 3de561e22659..51ed8fe71d2d 100644 --- a/drivers/net/ethernet/google/gve/gve.h +++ b/drivers/net/ethernet/google/gve/gve.h @@ -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 */ diff --git a/drivers/net/ethernet/google/gve/gve_adminq.h b/drivers/net/ethernet/google/gve/gve_adminq.h index 47c3d8f313fc..3953f6f7a427 100644 --- a/drivers/net/ethernet/google/gve/gve_adminq.h +++ b/drivers/net/ethernet/google/gve/gve_adminq.h @@ -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, diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c index b6805ad2011b..7647cd05b1d2 100644 --- a/drivers/net/ethernet/google/gve/gve_main.c +++ b/drivers/net/ethernet/google/gve/gve_main.c @@ -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 */ -- 2.25.1