diff options
Diffstat (limited to 'lib/kernel')
| -rw-r--r-- | lib/kernel/doc/src/seq_trace.xml | 11 | ||||
| -rw-r--r-- | lib/kernel/src/seq_trace.erl | 16 | ||||
| -rw-r--r-- | lib/kernel/test/seq_trace_SUITE.erl | 3 |
3 files changed, 20 insertions, 10 deletions
diff --git a/lib/kernel/doc/src/seq_trace.xml b/lib/kernel/doc/src/seq_trace.xml index 1feb3fcb07..5ac199b6a7 100644 --- a/lib/kernel/doc/src/seq_trace.xml +++ b/lib/kernel/doc/src/seq_trace.xml @@ -213,9 +213,10 @@ seq_trace:set_token(OldToken), % activate the trace token again <type name="tracer"/> <desc> <p>Sets the system tracer. The system tracer can be either a - process or port denoted by <c><anno>Tracer</anno></c>. Returns the previous - value (which can be <c>false</c> if no system tracer is - active).</p> + process, port or <seealso marker="erts:erl_tracer">tracer module</seealso> + denoted by <c><anno>Tracer</anno></c>. + Returns the previous value (which can be <c>false</c> if no system + tracer is active).</p> <p>Failure: <c>{badarg, Info}}</c> if <c><anno>Pid</anno></c> is not an existing local pid.</p> </desc> @@ -225,7 +226,7 @@ seq_trace:set_token(OldToken), % activate the trace token again <fsummary>Return the pid() or port() of the current system tracer.</fsummary> <type name="tracer"/> <desc> - <p>Returns the pid or port identifier of the current system + <p>Returns the pid, port identifier or tracer module of the current system tracer or <c>false</c> if no system tracer is activated.</p> </desc> </func> @@ -298,7 +299,7 @@ TimeStamp = {Seconds, Milliseconds, Microseconds} matches a message in a receive statement, according to the trace token carried by the received message, empty or not.</p> <p>On each Erlang node, a process can be set as the <em>system tracer</em>. - This process receives trace messages each time + This process will receive trace messages each time a message with a trace token is sent or received (if the trace token flag <c>send</c> or <c>'receive'</c> is set). The system tracer can then print each trace event, write it to a file, or diff --git a/lib/kernel/src/seq_trace.erl b/lib/kernel/src/seq_trace.erl index 01ac024c88..cc0c10909b 100644 --- a/lib/kernel/src/seq_trace.erl +++ b/lib/kernel/src/seq_trace.erl @@ -106,14 +106,24 @@ reset_trace() -> %% reset_trace(Pid) -> % this might be a useful function too --type tracer() :: (Pid :: pid()) | port() | 'false'. +-type tracer() :: (Pid :: pid()) | port() | + (TracerModule :: {module(), term()}) | + 'false'. -spec set_system_tracer(Tracer) -> OldTracer when Tracer :: tracer(), OldTracer :: tracer(). -set_system_tracer(Pid) -> - erlang:system_flag(sequential_tracer, Pid). +set_system_tracer({Module, State} = Tracer) -> + case erlang:module_loaded(Module) of + false -> + Module:enabled(trace_status, erlang:self(), State); + true -> + ok + end, + erlang:system_flag(sequential_tracer, Tracer); +set_system_tracer(Tracer) -> + erlang:system_flag(sequential_tracer, Tracer). -spec get_system_tracer() -> Tracer when Tracer :: tracer(). diff --git a/lib/kernel/test/seq_trace_SUITE.erl b/lib/kernel/test/seq_trace_SUITE.erl index 0a03503163..000994751f 100644 --- a/lib/kernel/test/seq_trace_SUITE.erl +++ b/lib/kernel/test/seq_trace_SUITE.erl @@ -787,7 +787,6 @@ start_tracer() -> seq_trace:set_system_tracer(Pid), Pid. - set_token_flags([]) -> ok; set_token_flags([no_timestamp|Flags]) -> @@ -836,7 +835,7 @@ check_ts(strict_monotonic_timestamp, Ts) -> ct:fail({unexpected_timestamp, Ts}) end, ok. - + start_node(Name, Param) -> test_server:start_node(Name, slave, [{args, Param}]). |