Re: [PATCH 04/15] net: Use trace_invoke_##name() at guarded tracepoint call sites

From: Vineeth Remanan Pillai

Date: Wed Mar 18 2026 - 09:42:23 EST


On Thu, Mar 12, 2026 at 11:31 AM Aaron Conole <aconole@xxxxxxxxxx> wrote:
>
> "Vineeth Pillai (Google)" <vineeth@xxxxxxxxxxxxxxx> writes:
>
> > Replace trace_foo() with the new trace_invoke_foo() at sites already
> > guarded by trace_foo_enabled(), avoiding a redundant
> > static_branch_unlikely() re-evaluation inside the tracepoint.
> > trace_invoke_foo() calls the tracepoint callbacks directly without
> > utilizing the static branch again.
> >
> > Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
> > Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > Signed-off-by: Vineeth Pillai (Google) <vineeth@xxxxxxxxxxxxxxx>
> > Assisted-by: Claude:claude-sonnet-4-6
> > ---
> > net/core/dev.c | 2 +-
> > net/core/xdp.c | 2 +-
> > net/openvswitch/actions.c | 2 +-
> > net/openvswitch/datapath.c | 2 +-
> > net/sctp/outqueue.c | 2 +-
> > net/tipc/node.c | 2 +-
> > 6 files changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/net/core/dev.c b/net/core/dev.c
> > index 14a83f2035b93..a48fae2bbf57e 100644
> > --- a/net/core/dev.c
> > +++ b/net/core/dev.c
> > @@ -6444,7 +6444,7 @@ void netif_receive_skb_list(struct list_head *head)
> > return;
> > if (trace_netif_receive_skb_list_entry_enabled()) {
> > list_for_each_entry(skb, head, list)
> > - trace_netif_receive_skb_list_entry(skb);
> > + trace_invoke_netif_receive_skb_list_entry(skb);
> > }
> > netif_receive_skb_list_internal(head);
> > trace_netif_receive_skb_list_exit(0);
> > diff --git a/net/core/xdp.c b/net/core/xdp.c
> > index 9890a30584ba7..53acc887c3434 100644
> > --- a/net/core/xdp.c
> > +++ b/net/core/xdp.c
> > @@ -362,7 +362,7 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,
> > xsk_pool_set_rxq_info(allocator, xdp_rxq);
> >
> > if (trace_mem_connect_enabled() && xdp_alloc)
> > - trace_mem_connect(xdp_alloc, xdp_rxq);
> > + trace_invoke_mem_connect(xdp_alloc, xdp_rxq);
> > return 0;
> > }
> >
> > diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c
> > index 792ca44a461da..420eb19322e85 100644
> > --- a/net/openvswitch/actions.c
> > +++ b/net/openvswitch/actions.c
> > @@ -1259,7 +1259,7 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
> > int err = 0;
> >
> > if (trace_ovs_do_execute_action_enabled())
> > - trace_ovs_do_execute_action(dp, skb, key, a, rem);
> > + trace_invoke_ovs_do_execute_action(dp, skb, key, a, rem);
>
> Maybe we should just remove the guard here instead of calling the
> invoke. That seems better to me. It wouldn't need to belong to this
> series.
>
> > /* Actions that rightfully have to consume the skb should do it
> > * and return directly.
> > diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
> > index e209099218b41..02451629e888e 100644
> > --- a/net/openvswitch/datapath.c
> > +++ b/net/openvswitch/datapath.c
> > @@ -335,7 +335,7 @@ int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
> > int err;
> >
> > if (trace_ovs_dp_upcall_enabled())
> > - trace_ovs_dp_upcall(dp, skb, key, upcall_info);
> > + trace_invoke_ovs_dp_upcall(dp, skb, key, upcall_info);
>
> Same as above. Seems OVS tracepoints are the only ones that include
> the guard without any real reason.
>

Makes sense. Its simple enough that I think I will include it as a
separate patch in v2 and remove these changes from this patch. Thanks
for pointing it out.

Thanks,
Vineeth