On Mon, Jul 06, 2015 at 12:15:45PM -0700, Cong Wang 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`). > > Ideally, we need to split the sched_switch event into two: > sched_in event before we perform the switch, and sched_out > event after we perform the switch. However, for compatibility, > we can not change the sched_switch event. So before we have > trace event alias, we can just reuse sched_switch and introduce > sched_switch_post event instead.
No.. its still horrible. You're trying to solve perf problems with ftrace; this cannot work. Does this patch by Adrian work for you? I think it solves this problem and a bunch of others. lkml.kernel.org/r/[email protected] -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
