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 <edumazet@google.com>
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-6-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 16 insertions, 9 deletions

diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index aaa3b58e2e3e..54d03b0628d2 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;