| Message ID | 20230821142339.1889961-1-idosch@nvidia.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 504fc6f4f7f681d2a03aa5f68aad549d90eab853 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next] vrf: Remove unnecessary RCU-bh critical section | expand |
On Mon, Aug 21, 2023 at 05:23:39PM +0300, Ido Schimmel wrote: > dev_queue_xmit_nit() already uses rcu_read_lock() / rcu_read_unlock() > and nothing suggests that softIRQs should be disabled around it. > Therefore, remove the rcu_read_lock_bh() / rcu_read_unlock_bh() > surrounding it. > > Tested using [1] with lockdep enabled. > > [1] > #!/bin/bash > > ip link add name vrf1 up type vrf table 100 > ip link add name veth0 type veth peer name veth1 > ip link set dev veth1 master vrf1 > ip link set dev veth0 up > ip link set dev veth1 up > ip address add 192.0.2.1/24 dev veth0 > ip address add 192.0.2.2/24 dev veth1 > ip rule add pref 32765 table local > ip rule del pref 0 > tcpdump -i vrf1 -c 20 -w /dev/null & > sleep 10 > ping -i 0.1 -c 10 -q 192.0.2.2 > > Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Simon Horman <horms@kernel.org>
On 8/21/23 8:23 AM, Ido Schimmel wrote: > dev_queue_xmit_nit() already uses rcu_read_lock() / rcu_read_unlock() > and nothing suggests that softIRQs should be disabled around it. > Therefore, remove the rcu_read_lock_bh() / rcu_read_unlock_bh() > surrounding it. > > Tested using [1] with lockdep enabled. > > [1] > #!/bin/bash > > ip link add name vrf1 up type vrf table 100 > ip link add name veth0 type veth peer name veth1 > ip link set dev veth1 master vrf1 > ip link set dev veth0 up > ip link set dev veth1 up > ip address add 192.0.2.1/24 dev veth0 > ip address add 192.0.2.2/24 dev veth1 > ip rule add pref 32765 table local > ip rule del pref 0 > tcpdump -i vrf1 -c 20 -w /dev/null & > sleep 10 > ping -i 0.1 -c 10 -q 192.0.2.2 > > Signed-off-by: Ido Schimmel <idosch@nvidia.com> > --- > drivers/net/vrf.c | 2 -- > 1 file changed, 2 deletions(-) > Reviewed-by: David Ahern <dsahern@kernel.org>
Hello: This patch was applied to netdev/net-next.git (main) by Jakub Kicinski <kuba@kernel.org>: On Mon, 21 Aug 2023 17:23:39 +0300 you wrote: > dev_queue_xmit_nit() already uses rcu_read_lock() / rcu_read_unlock() > and nothing suggests that softIRQs should be disabled around it. > Therefore, remove the rcu_read_lock_bh() / rcu_read_unlock_bh() > surrounding it. > > Tested using [1] with lockdep enabled. > > [...] Here is the summary with links: - [net-next] vrf: Remove unnecessary RCU-bh critical section https://git.kernel.org/netdev/net-next/c/504fc6f4f7f6 You are awesome, thank you!
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index 6043e63b42f9..43f374444684 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -638,9 +638,7 @@ static void vrf_finish_direct(struct sk_buff *skb) eth_zero_addr(eth->h_dest); eth->h_proto = skb->protocol; - rcu_read_lock_bh(); dev_queue_xmit_nit(skb, vrf_dev); - rcu_read_unlock_bh(); skb_pull(skb, ETH_HLEN); }
dev_queue_xmit_nit() already uses rcu_read_lock() / rcu_read_unlock() and nothing suggests that softIRQs should be disabled around it. Therefore, remove the rcu_read_lock_bh() / rcu_read_unlock_bh() surrounding it. Tested using [1] with lockdep enabled. [1] #!/bin/bash ip link add name vrf1 up type vrf table 100 ip link add name veth0 type veth peer name veth1 ip link set dev veth1 master vrf1 ip link set dev veth0 up ip link set dev veth1 up ip address add 192.0.2.1/24 dev veth0 ip address add 192.0.2.2/24 dev veth1 ip rule add pref 32765 table local ip rule del pref 0 tcpdump -i vrf1 -c 20 -w /dev/null & sleep 10 ping -i 0.1 -c 10 -q 192.0.2.2 Signed-off-by: Ido Schimmel <idosch@nvidia.com> --- drivers/net/vrf.c | 2 -- 1 file changed, 2 deletions(-)