In vm_call_method_each_type, check for c_call and c_return events before
dispatching to vm_call_ivar and vm_call_attrset. With this approach, the
call cache will still dispatch directly to those functions, so this
change will only decrease performance for the first (uncached) call, and
even then, the performance decrease is very minimal.
This approach requires that we clear the call caches when tracing is
enabled or disabled. The approach currently switches all vm_call_ivar
and vm_call_attrset call caches to vm_call_general any time tracing is
enabled or disabled. So it could theoretically result in a slowdown for
code that constantly enables or disables tracing.
This approach does not handle targeted tracepoints, but from my testing,
c_call and c_return events are not supported for targeted tracepoints,
so that shouldn't matter.
This includes a benchmark showing the performance decrease is minimal
if detectable at all.
Fixes [Bug #16383]
Fixes [Bug #10470]
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Jeremy Evans