From 310ae9eb2617c62deedef8f121d7ca1ae774fa76 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 24 Mar 2025 15:45:32 -0700 Subject: net: designate queue -> napi linking as "ops protected" netdev netlink is the only reader of netdev_{,rx_}queue->napi, and it already holds netdev->lock. Switch protection of the writes to netdev->lock to "ops protected". The expectation will be now that accessing queue->napi will require netdev->lock for "ops locked" drivers, and rtnl_lock for all other drivers. Current "ops locked" drivers don't require any changes. gve and netdevsim use _locked() helpers right next to netif_queue_set_napi() so they must be holding the instance lock. iavf doesn't call it. bnxt is a bit messy but all paths seem locked. Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20250324224537.248800-7-kuba@kernel.org Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 60ef367d8575..fa79145518d1 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -710,7 +710,7 @@ struct netdev_queue { * slow- / control-path part */ /* NAPI instance for the queue - * Readers and writers must hold RTNL + * "ops protected", see comment about net_device::lock */ struct napi_struct *napi; @@ -2526,7 +2526,8 @@ struct net_device { * Double ops protects: * @real_num_rx_queues, @real_num_tx_queues * - * Also protects some fields in struct napi_struct. + * Also protects some fields in: + * struct napi_struct, struct netdev_queue, struct netdev_rx_queue * * Ordering: take after rtnl_lock. */ -- cgit v1.2.3