Re: [PATCH net-next] trace: tcp: Add tracepoint for tcp_sendmsg()

On Mon, Feb 24, 2025 at 7:24 PM Breno Leitao [off-list ref] wrote:

Add a lightweight tracepoint to monitor TCP sendmsg operations, enabling
the tracing of TCP messages being sent.

Meta has been using BPF programs to monitor this function for years,
indicating significant interest in observing this important
functionality. Adding a proper tracepoint provides a stable API for all
users who need visibility into TCP message transmission.

The implementation uses DECLARE_TRACE instead of TRACE_EVENT to avoid
creating unnecessary trace event infrastructure and tracefs exports,
keeping the implementation minimal while stabilizing the API.

Given that this patch creates a rawtracepoint, you could hook into it
using regular tooling, like bpftrace, using regular rawtracepoint
infrastructure, such as:

        rawtracepoint:tcp_sendmsg_tp {
                ....
        }

I would expect tcp_sendmsg() being stable enough ?

kprobe:tcp_sendmsg {
}