On Mon, Dec 18, 2017 at 06:51:43PM -0500, Steven Rostedt wrote: > On Tue, 19 Dec 2017 08:16:14 +1100 > "Tobin C. Harding" <m...@tobin.cc> wrote: > > > > > #endif /* _LINUX_KERNEL_TRACE_H */ > > > > diff --git a/kernel/trace/trace_events_hist.c > > > > b/kernel/trace/trace_events_hist.c > > > > index 1e1558c99d56..3e28522a76f4 100644 > > > > --- a/kernel/trace/trace_events_hist.c > > > > +++ b/kernel/trace/trace_events_hist.c > > > > @@ -982,7 +982,7 @@ static void hist_trigger_stacktrace_print(struct > > > > seq_file *m, > > > > return; > > > > > > > > seq_printf(m, "%*c", 1 + spaces, ' '); > > > > - sprint_symbol(str, stacktrace_entries[i]); > > > > + trace_sprint_symbol_addr(str, stacktrace_entries[i]); > > > > > > > > If you have the time to give me some brief pointers on how I should go > > about testing this I'd love to test it before the next version. I know > > very little about ftrace. > > For hitting the histogram stacktrace trigger (this code path), make > sure you have CONFIG_HIST_TRIGGERS enabled. And then do: > > # cd /sys/kernel/debug/tracing > # echo 'hist:keys=common_pid.execname,stacktrace:vals=prev_state' > \ > events/sched/sched_switch/trigger > # cat events/sched/sched_switch/hist > > For the "sym" part, you can do (from the same directory): > > # echo 'hist:keys=call_site.sym:vals=bytes_req' > \ > events/kmem/kmalloc/trigger > # cat events/kmem/kmalloc/hist > > > And for sym-offset: > > # echo 'hist:keys=call_site.sym-offset:vals=bytes_req' > \ > events/kmem/kmalloc/trigger > # cat events/kmem/kmalloc/hist > > -- Steve
Thanks, you're the man
