From: Jakub Kicinski Date: Thu, 10 Apr 2025 01:42:46 +0000 (-0700) Subject: net: convert dev->rtnl_link_state to a bool X-Git-Tag: v6.16-rc1~132^2~320 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=097f171f98289cf737437599c40b0d1e81266e9e;p=thirdparty%2Fkernel%2Flinux.git net: convert dev->rtnl_link_state to a bool netdevice reg_state was split into two 16 bit enums back in 2010 in commit a2835763e130 ("rtnetlink: handle rtnl_link netlink notifications manually"). Since the split the fields have been moved apart, and last year we converted reg_state to a normal u8 in commit 4d42b37def70 ("net: convert dev->reg_state to u8"). rtnl_link_state being a 16 bitfield makes no sense. Convert it to a single bool, it seems very unlikely after 15 years that we'll need more values in it. We could drop dev->rtnl_link_ops from the conditions but feels like having it there more clearly points at the reason for this hack. Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20250410014246.780885-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- diff --git a/Documentation/networking/net_cachelines/net_device.rst b/Documentation/networking/net_cachelines/net_device.rst index 6327e689e8a84..ca8605eb82ffc 100644 --- a/Documentation/networking/net_cachelines/net_device.rst +++ b/Documentation/networking/net_cachelines/net_device.rst @@ -131,7 +131,7 @@ struct ref_tracker_dir refcnt_tracker struct list_head link_watch_list enum:8 reg_state bool dismantle -enum:16 rtnl_link_state +bool rtnl_link_initilizing bool needs_free_netdev void*priv_destructor struct net_device struct netpoll_info* npinfo read_mostly napi_poll/napi_poll_lock diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d8544f6a680cd..e6036b82ef4cf 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1946,9 +1946,6 @@ enum netdev_reg_state { * * @reg_state: Register/unregister state machine * @dismantle: Device is going to be freed - * @rtnl_link_state: This enum represents the phases of creating - * a new link - * * @needs_free_netdev: Should unregister perform free_netdev? * @priv_destructor: Called from unregister * @npinfo: XXX: need comments on this one @@ -2363,11 +2360,8 @@ struct net_device { /** @moving_ns: device is changing netns, protected by @lock */ bool moving_ns; - - enum { - RTNL_LINK_INITIALIZED, - RTNL_LINK_INITIALIZING, - } rtnl_link_state:16; + /** @rtnl_link_initializing: Device being created, suppress events */ + bool rtnl_link_initializing; bool needs_free_netdev; void (*priv_destructor)(struct net_device *dev); diff --git a/net/core/dev.c b/net/core/dev.c index d0563ddff6ca9..03d20a98f8b70 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -11110,8 +11110,7 @@ int register_netdevice(struct net_device *dev) * Prevent userspace races by waiting until the network * device is fully setup before sending notifications. */ - if (!dev->rtnl_link_ops || - dev->rtnl_link_state == RTNL_LINK_INITIALIZED) + if (!(dev->rtnl_link_ops && dev->rtnl_link_initializing)) rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); out: @@ -12025,8 +12024,7 @@ void unregister_netdevice_many_notify(struct list_head *head, */ call_netdevice_notifiers(NETDEV_UNREGISTER, dev); - if (!dev->rtnl_link_ops || - dev->rtnl_link_state == RTNL_LINK_INITIALIZED) + if (!(dev->rtnl_link_ops && dev->rtnl_link_initializing)) skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, GFP_KERNEL, NULL, 0, portid, nlh); diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 39a5b72e861f6..38526210b8fdd 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3580,7 +3580,7 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm, u32 portid, const struct nlmsghdr *nlh) { - unsigned int old_flags; + unsigned int old_flags, changed; int err; old_flags = dev->flags; @@ -3591,12 +3591,13 @@ int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm, return err; } - if (dev->rtnl_link_state == RTNL_LINK_INITIALIZED) { - __dev_notify_flags(dev, old_flags, (old_flags ^ dev->flags), portid, nlh); - } else { - dev->rtnl_link_state = RTNL_LINK_INITIALIZED; - __dev_notify_flags(dev, old_flags, ~0U, portid, nlh); + changed = old_flags ^ dev->flags; + if (dev->rtnl_link_initializing) { + dev->rtnl_link_initializing = false; + changed = ~0U; } + + __dev_notify_flags(dev, old_flags, changed, portid, nlh); return 0; } EXPORT_SYMBOL(rtnl_configure_link); @@ -3654,7 +3655,7 @@ struct net_device *rtnl_create_link(struct net *net, const char *ifname, dev_net_set(dev, net); dev->rtnl_link_ops = ops; - dev->rtnl_link_state = RTNL_LINK_INITIALIZING; + dev->rtnl_link_initializing = true; if (tb[IFLA_MTU]) { u32 mtu = nla_get_u32(tb[IFLA_MTU]);