From cae03e5bdd9e0c8570506c50f1f234da40201732 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Wed, 5 Mar 2025 08:37:23 -0800 Subject: [PATCH] net: hold netdev instance lock during queue operations For the drivers that use queue management API, switch to the mode where core stack holds the netdev instance lock. This affects the following drivers: - bnxt - gve - netdevsim Originally I locked only start/stop, but switched to holding the lock over all iterations to make them look atomic to the device (feels like it should be easier to reason about). Reviewed-by: Eric Dumazet Cc: Saeed Mahameed Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250305163732.2766420-6-sdf@fomichev.me Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 16 ++++++------- drivers/net/ethernet/google/gve/gve_main.c | 12 ++++++---- drivers/net/ethernet/google/gve/gve_utils.c | 6 ++--- drivers/net/netdevsim/netdev.c | 25 +++++++++++++-------- include/linux/netdevice.h | 2 +- net/core/netdev_rx_queue.c | 5 +++++ 6 files changed, 41 insertions(+), 25 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 15c57a06ecaf4..ead9fcaad6bdd 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -11508,7 +11508,7 @@ static int bnxt_request_irq(struct bnxt *bp) if (rc) break; - netif_napi_set_irq(&bp->bnapi[i]->napi, irq->vector); + netif_napi_set_irq_locked(&bp->bnapi[i]->napi, irq->vector); irq->requested = 1; if (zalloc_cpumask_var(&irq->cpu_mask, GFP_KERNEL)) { @@ -11557,9 +11557,9 @@ static void bnxt_del_napi(struct bnxt *bp) for (i = 0; i < bp->cp_nr_rings; i++) { struct bnxt_napi *bnapi = bp->bnapi[i]; - __netif_napi_del(&bnapi->napi); + __netif_napi_del_locked(&bnapi->napi); } - /* We called __netif_napi_del(), we need + /* We called __netif_napi_del_locked(), we need * to respect an RCU grace period before freeing napi structures. */ synchronize_net(); @@ -11578,12 +11578,12 @@ static void bnxt_init_napi(struct bnxt *bp) cp_nr_rings--; for (i = 0; i < cp_nr_rings; i++) { bnapi = bp->bnapi[i]; - netif_napi_add_config(bp->dev, &bnapi->napi, poll_fn, - bnapi->index); + netif_napi_add_config_locked(bp->dev, &bnapi->napi, poll_fn, + bnapi->index); } if (BNXT_CHIP_TYPE_NITRO_A0(bp)) { bnapi = bp->bnapi[cp_nr_rings]; - netif_napi_add(bp->dev, &bnapi->napi, bnxt_poll_nitroa0); + netif_napi_add_locked(bp->dev, &bnapi->napi, bnxt_poll_nitroa0); } } @@ -11604,7 +11604,7 @@ static void bnxt_disable_napi(struct bnxt *bp) cpr->sw_stats->tx.tx_resets++; if (bnapi->in_reset) cpr->sw_stats->rx.rx_resets++; - napi_disable(&bnapi->napi); + napi_disable_locked(&bnapi->napi); } } @@ -11626,7 +11626,7 @@ static void bnxt_enable_napi(struct bnxt *bp) INIT_WORK(&cpr->dim.work, bnxt_dim_work); cpr->dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE; } - napi_enable(&bnapi->napi); + napi_enable_locked(&bnapi->napi); } } diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c index 029be8342b7b8..6dcdcaf518f4c 100644 --- a/drivers/net/ethernet/google/gve/gve_main.c +++ b/drivers/net/ethernet/google/gve/gve_main.c @@ -1968,7 +1968,7 @@ static void gve_turndown(struct gve_priv *priv) netif_queue_set_napi(priv->dev, idx, NETDEV_QUEUE_TYPE_TX, NULL); - napi_disable(&block->napi); + napi_disable_locked(&block->napi); } for (idx = 0; idx < priv->rx_cfg.num_queues; idx++) { int ntfy_idx = gve_rx_idx_to_ntfy(priv, idx); @@ -1979,7 +1979,7 @@ static void gve_turndown(struct gve_priv *priv) netif_queue_set_napi(priv->dev, idx, NETDEV_QUEUE_TYPE_RX, NULL); - napi_disable(&block->napi); + napi_disable_locked(&block->napi); } /* Stop tx queues */ @@ -2009,7 +2009,7 @@ static void gve_turnup(struct gve_priv *priv) if (!gve_tx_was_added_to_block(priv, idx)) continue; - napi_enable(&block->napi); + napi_enable_locked(&block->napi); if (idx < priv->tx_cfg.num_queues) netif_queue_set_napi(priv->dev, idx, @@ -2037,7 +2037,7 @@ static void gve_turnup(struct gve_priv *priv) if (!gve_rx_was_added_to_block(priv, idx)) continue; - napi_enable(&block->napi); + napi_enable_locked(&block->napi); netif_queue_set_napi(priv->dev, idx, NETDEV_QUEUE_TYPE_RX, &block->napi); @@ -2887,6 +2887,7 @@ static int gve_suspend(struct pci_dev *pdev, pm_message_t state) priv->suspend_cnt++; rtnl_lock(); + netdev_lock(netdev); if (was_up && gve_close(priv->dev)) { /* If the dev was up, attempt to close, if close fails, reset */ gve_reset_and_teardown(priv, was_up); @@ -2895,6 +2896,7 @@ static int gve_suspend(struct pci_dev *pdev, pm_message_t state) gve_teardown_priv_resources(priv); } priv->up_before_suspend = was_up; + netdev_unlock(netdev); rtnl_unlock(); return 0; } @@ -2907,7 +2909,9 @@ static int gve_resume(struct pci_dev *pdev) priv->resume_cnt++; rtnl_lock(); + netdev_lock(netdev); err = gve_reset_recovery(priv, priv->up_before_suspend); + netdev_unlock(netdev); rtnl_unlock(); return err; } diff --git a/drivers/net/ethernet/google/gve/gve_utils.c b/drivers/net/ethernet/google/gve/gve_utils.c index 30fef100257e6..ace9b8698021f 100644 --- a/drivers/net/ethernet/google/gve/gve_utils.c +++ b/drivers/net/ethernet/google/gve/gve_utils.c @@ -110,13 +110,13 @@ void gve_add_napi(struct gve_priv *priv, int ntfy_idx, { struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx]; - netif_napi_add(priv->dev, &block->napi, gve_poll); - netif_napi_set_irq(&block->napi, block->irq); + netif_napi_add_locked(priv->dev, &block->napi, gve_poll); + netif_napi_set_irq_locked(&block->napi, block->irq); } void gve_remove_napi(struct gve_priv *priv, int ntfy_idx) { struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx]; - netif_napi_del(&block->napi); + netif_napi_del_locked(&block->napi); } diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c index aaa3b58e2e3e1..54d03b0628d22 100644 --- a/drivers/net/netdevsim/netdev.c +++ b/drivers/net/netdevsim/netdev.c @@ -683,7 +683,8 @@ nsim_queue_mem_alloc(struct net_device *dev, void *per_queue_mem, int idx) goto err_free; if (!ns->rq_reset_mode) - netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx); + netif_napi_add_config_locked(dev, &qmem->rq->napi, nsim_poll, + idx); return 0; @@ -700,7 +701,7 @@ static void nsim_queue_mem_free(struct net_device *dev, void *per_queue_mem) page_pool_destroy(qmem->pp); if (qmem->rq) { if (!ns->rq_reset_mode) - netif_napi_del(&qmem->rq->napi); + netif_napi_del_locked(&qmem->rq->napi); page_pool_destroy(qmem->rq->page_pool); nsim_queue_free(qmem->rq); } @@ -712,9 +713,11 @@ nsim_queue_start(struct net_device *dev, void *per_queue_mem, int idx) struct nsim_queue_mem *qmem = per_queue_mem; struct netdevsim *ns = netdev_priv(dev); + netdev_assert_locked(dev); + if (ns->rq_reset_mode == 1) { ns->rq[idx]->page_pool = qmem->pp; - napi_enable(&ns->rq[idx]->napi); + napi_enable_locked(&ns->rq[idx]->napi); return 0; } @@ -722,15 +725,17 @@ nsim_queue_start(struct net_device *dev, void *per_queue_mem, int idx) * here we want to test various call orders. */ if (ns->rq_reset_mode == 2) { - netif_napi_del(&ns->rq[idx]->napi); - netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx); + netif_napi_del_locked(&ns->rq[idx]->napi); + netif_napi_add_config_locked(dev, &qmem->rq->napi, nsim_poll, + idx); } else if (ns->rq_reset_mode == 3) { - netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx); - netif_napi_del(&ns->rq[idx]->napi); + netif_napi_add_config_locked(dev, &qmem->rq->napi, nsim_poll, + idx); + netif_napi_del_locked(&ns->rq[idx]->napi); } ns->rq[idx] = qmem->rq; - napi_enable(&ns->rq[idx]->napi); + napi_enable_locked(&ns->rq[idx]->napi); return 0; } @@ -740,7 +745,9 @@ static int nsim_queue_stop(struct net_device *dev, void *per_queue_mem, int idx) struct nsim_queue_mem *qmem = per_queue_mem; struct netdevsim *ns = netdev_priv(dev); - napi_disable(&ns->rq[idx]->napi); + netdev_assert_locked(dev); + + napi_disable_locked(&ns->rq[idx]->napi); if (ns->rq_reset_mode == 1) { qmem->pp = ns->rq[idx]->page_pool; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 69951eeb96d26..abda17b15950a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2755,7 +2755,7 @@ static inline void netdev_assert_locked_or_invisible(struct net_device *dev) static inline bool netdev_need_ops_lock(struct net_device *dev) { - bool ret = false; + bool ret = !!dev->queue_mgmt_ops; #if IS_ENABLED(CONFIG_NET_SHAPER) ret |= !!dev->netdev_ops->net_shaper_ops; diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c index ddd54e1e72897..7419c41fd3cb9 100644 --- a/net/core/netdev_rx_queue.c +++ b/net/core/netdev_rx_queue.c @@ -30,6 +30,8 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx) goto err_free_new_mem; } + netdev_lock(dev); + err = qops->ndo_queue_mem_alloc(dev, new_mem, rxq_idx); if (err) goto err_free_old_mem; @@ -52,6 +54,8 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx) qops->ndo_queue_mem_free(dev, old_mem); + netdev_unlock(dev); + kvfree(old_mem); kvfree(new_mem); @@ -76,6 +80,7 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx) qops->ndo_queue_mem_free(dev, new_mem); err_free_old_mem: + netdev_unlock(dev); kvfree(old_mem); err_free_new_mem: