b0e3f1bdf9
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 <gbastien@versatic.net> CC: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> CC: Steven Rostedt <rostedt@goodmis.org> CC: Ingo Molnar <mingo@redhat.com> CC: David S. Miller <davem@davemloft.net> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> (tracing side) Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| events | ||
| bpf_probe.h | ||
| define_trace.h | ||
| perf.h | ||
| syscall.h | ||
| trace_events.h | ||