On Mon, Jul 6, 2015 at 5:15 PM, Steven Rostedt <rost...@goodmis.org> wrote: > On Mon, 6 Jul 2015 12:15:45 -0700 > Cong Wang <xiyou.wangc...@gmail.com> wrote: > >> Currently we only have one sched_switch trace event >> for task switching, which is generated very early during >> task switch. When we try to monitor per-container perf >> events, this is not what we expect. >> >> For example, we have a process A which is in the cgroup >> we monitor, and process B which isn't, when kernel switches >> from B to A, the sched_switch event is not recorded for this >> cgroup since it belongs to B (current process is still B >> util we finish the switch), but we require this event to >> signal that process A in this cgroup gets scheduled. This is >> crucial for calculating schedule latency (like `perf sched`). > > I just want to understand this correctly. Does perf sched only listen > to events that are executed by the task in a particular cgroup? There's > no way to say "check sched_switch field next"? >
perf_event cgroup needs to be specified in cmdline and `perf sched` doesn't support that currently, I wrote my own tool to do this. (I have some patch to add it to `perf sched`) As I replied in the previous thread, we can certainly check if a process belongs to a cgroup by tracking the PID's, but that is not easy. > > This looks identical to trace_sched_switch. Please convert both to a > DECLARE_EVENT_CLASS() and DEFINE_EVENT()s. > Not identical, I rename 'next' to 'curr' since switch is done 'next' becomes meaningless. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
