| Message ID | 20200308134706.18727-1-ap420073@gmail.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next] net: rmnet: set NETIF_F_LLTX flag | expand |
On 2020-03-08 07:47, Taehee Yoo wrote: > The rmnet_vnd_setup(), which is the callback of ->ndo_start_xmit() is > allowed to call concurrently because it uses RCU protected data. > So, it doesn't need tx lock. > > Signed-off-by: Taehee Yoo <ap420073@gmail.com> > --- > drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > index d7c52e398e4a..d58b51d277f1 100644 > --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > @@ -212,6 +212,8 @@ void rmnet_vnd_setup(struct net_device *rmnet_dev) > rmnet_dev->needs_free_netdev = true; > rmnet_dev->ethtool_ops = &rmnet_ethtool_ops; > > + rmnet_dev->features |= NETIF_F_LLTX; > + > /* This perm addr will be used as interface identifier by IPv6 */ > rmnet_dev->addr_assign_type = NET_ADDR_RANDOM; > eth_random_addr(rmnet_dev->perm_addr); Hi Taehee It seems the flag is deprecated per documentation. https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/tree/Documentation/networking/netdevices.txt#n73
On 3/8/20 5:28 PM, subashab@codeaurora.org wrote: > On 2020-03-08 07:47, Taehee Yoo wrote: >> The rmnet_vnd_setup(), which is the callback of ->ndo_start_xmit() is >> allowed to call concurrently because it uses RCU protected data. >> So, it doesn't need tx lock. >> >> Signed-off-by: Taehee Yoo <ap420073@gmail.com> >> --- >> drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c >> b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c >> index d7c52e398e4a..d58b51d277f1 100644 >> --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c >> +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c >> @@ -212,6 +212,8 @@ void rmnet_vnd_setup(struct net_device *rmnet_dev) >> rmnet_dev->needs_free_netdev = true; >> rmnet_dev->ethtool_ops = &rmnet_ethtool_ops; >> >> + rmnet_dev->features |= NETIF_F_LLTX; >> + >> /* This perm addr will be used as interface identifier by IPv6 */ >> rmnet_dev->addr_assign_type = NET_ADDR_RANDOM; >> eth_random_addr(rmnet_dev->perm_addr); > > Hi Taehee > > It seems the flag is deprecated per documentation. > > https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/tree/Documentation/networking/netdevices.txt#n73 This does not count for virtual drivers, like macvlan, bonding, tunnels... If your ndo_start_xmit() calls dev_queue_xmit() after switching skb->dev to another device, you do not need a lock.
From: Taehee Yoo <ap420073@gmail.com> Date: Sun, 8 Mar 2020 13:47:06 +0000 > The rmnet_vnd_setup(), which is the callback of ->ndo_start_xmit() is > allowed to call concurrently because it uses RCU protected data. > So, it doesn't need tx lock. > > Signed-off-by: Taehee Yoo <ap420073@gmail.com> Applied, thanks.
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c index d7c52e398e4a..d58b51d277f1 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c @@ -212,6 +212,8 @@ void rmnet_vnd_setup(struct net_device *rmnet_dev) rmnet_dev->needs_free_netdev = true; rmnet_dev->ethtool_ops = &rmnet_ethtool_ops; + rmnet_dev->features |= NETIF_F_LLTX; + /* This perm addr will be used as interface identifier by IPv6 */ rmnet_dev->addr_assign_type = NET_ADDR_RANDOM; eth_random_addr(rmnet_dev->perm_addr);
The rmnet_vnd_setup(), which is the callback of ->ndo_start_xmit() is allowed to call concurrently because it uses RCU protected data. So, it doesn't need tx lock. Signed-off-by: Taehee Yoo <ap420073@gmail.com> --- drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c | 2 ++ 1 file changed, 2 insertions(+)