From: Geneviève Bastien <gbast...@versatic.net> Date: Tue, 27 Nov 2018 12:52:39 -0500
> Trace events are already present for the receive entry points, to indicate > how the reception entered the stack. > > This patch adds the corresponding exit trace events that will bound the > reception such that all events occurring between the entry and the exit > can be considered as part of the reception context. This greatly helps > for dependency and root cause analyses. > > Without this, it is not possible with tracepoint instrumentation to > determine whether a sched_wakeup event following a netif_receive_skb > event is the result of the packet reception or a simple coincidence after > further processing by the thread. It is possible using other mechanisms > like kretprobes, but considering the "entry" points are already present, > it would be good to add the matching exit events. > > In addition to linking packets with wakeups, the entry/exit event pair > can also be used to perform network stack latency analyses. > > Signed-off-by: Geneviève Bastien <gbast...@versatic.net> > CC: Mathieu Desnoyers <mathieu.desnoy...@efficios.com> > CC: Steven Rostedt <rost...@goodmis.org> > CC: Ingo Molnar <mi...@redhat.com> > CC: David S. Miller <da...@davemloft.net> > Reviewed-by: Steven Rostedt (VMware) <rost...@goodmis.org> (tracing > side) Applied to net-next, thanks for sticking with this.
