On Fri, Sep 23, 2016 at 12:49:30PM -0400, Julien Desfossez wrote: > With this macro, we propose new versions of the sched_switch, sched_waking, > sched_process_fork and sched_pi_setprio tracepoint probes that contain more > scheduling information and get rid of the "prio" field. We also add the PI > information to these tracepoints, so if a process is currently boosted, we > show > the name and PID of the top waiter. This allows to quickly see the blocking > chain even if some of the trace background is missing.
Urgh.. bigger mess than ever :-( So I thought the initial idea was to provide a 'blocked-on' tracepoint, along with with the 'prio-changed' tracepoint, so you can reconstruct the entire PI chain. The only problem with that was initial state; when you start tracing (or miss the start of a trace) its hard (impossible) to know what the current state is. But now you send a patch-set that just adds a metric ton of tracepoints. This doesn't fix the current mess, it makes it worse :-(
