Stefan Hajnoczi 3932ef3ffb trace: add TRACE_<event>_BACKEND_DSTATE() ... QEMU keeps track of trace event enabled/disabled state and provides monitor commands to inspect and modify the "dstate". SystemTap and LTTng UST maintain independent enabled/disabled states for each trace event, the other backends rely on QEMU dstate. Introduce a new per-event macro that combines backend-specific dstate like this: #define TRACE_MY_EVENT_BACKEND_DSTATE() ( \ QEMU_MY_EVENT_ENABLED() || /* SystemTap */ \ tracepoint_enabled(qemu, my_event) /* LTTng UST */ || \ false) This will be used to extend trace_event_get_state() in the next patch. [Daniel Berrange pointed out that QEMU_MY_EVENT_ENABLED() must be true by default, not false. This way events will fire even if the DTrace implementation does not implement the SystemTap semaphores feature. Ubuntu Precise uses lttng-ust-dev 2.0.2 which does not have tracepoint_enabled(), so we need a compatibility wrapper to keep Travis builds passing. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170731140718.22010-2-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> fixup! trace: add TRACE_<event>_BACKEND_DSTATE()		2017-08-01 12:07:48 +01:00
..
__init__.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00
dtrace.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00
ftrace.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00
log.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00
simple.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00
syslog.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00
ust.py	trace: add TRACE_<event>_BACKEND_DSTATE()	2017-08-01 12:07:48 +01:00