Plugin to filter traces based on thapi_start/stop

Author: thilinarmtb

utils/Makefile.am

@@ -41,19 +41,38 @@ bin_PROGRAMS = thapi_metadata
 
 include_HEADERS = thapi.h
 
-BUILT_SOURCES += \
-	thapi_tracepoints.h \
-	thapi_tracepoints.c
-
+lib_LTLIBRARIES = libThapi.la
 nodist_libThapi_la_SOURCES = \
 	thapi_tracepoints.h \
 	thapi_tracepoints.c
-
 libThapi_la_SOURCES = thapi_toggle.c
 libThapi_la_CFLAGS = $(LTTNG_FLAGS) $(LTTNG_UST_CFLAGS)
 libThapi_la_LDFLAGS = $(LTTNG_UST_LIBS)
 
-lib_LTLIBRARIES = libThapi.la
+BTX_THAPI_GENERATED = \
+	btx_thapi/metababel/metababel.h \
+	btx_thapi/metababel/btx_component.h \
+	btx_thapi/metababel/btx_component.c \
+	btx_thapi/metababel/btx_upstream.h \
+	btx_thapi/metababel/btx_upstream.c \
+	btx_thapi/metababel/btx_downstream.h \
+	btx_thapi/metababel/btx_downstream.c \
+	btx_thapi/btx_main.c
+
+$(BTX_THAPI_GENERATED): btx_thapi.yaml thapi_callbacks.c
+	$(METABABEL) --enable-callbacks on_downstream --component-type FILTER \
+		--upstream $(top_srcdir)/utils/btx_thapi.yaml --downstream $(top_srcdir)/utils/btx_thapi.yaml \
+		-o btx_thapi
+
+noinst_LTLIBRARIES = libThapiPlugin.la
+nodist_libThapiPlugin_la_SOURCES = $(BTX_THAPI_GENERATED)
+libThapiPlugin_la_SOURCES = thapi_callbacks.c
+libThapiPlugin_la_CFLAGS = -fPIC -shared -Wall -Wextra -Wno-unused-parameter $(BABELTRACE2_CFLAGS) -I./btx_thapi -I$(top_srcdir)/utils/include
+
+BUILT_SOURCES += \
+	thapi_tracepoints.h \
+	thapi_tracepoints.c \
+	$(BTX_THAPI_GENERATED)
 
 bin_SCRIPTS = \
 	babeltrace_thapi
@@ -74,6 +93,7 @@ CLEANFILES = \
 	version \
 	optparse_thapi.rb \
 	lttng/tracepoint_gen.h \
+	$(BTX_THAPI_GENERATED) \
 	$(BUILT_SOURCES)
 
 EXTRA_DIST = \
@@ -87,6 +107,7 @@ EXTRA_DIST = \
 	dump_trace_format.rb \
 	thapi_metadata_tracepoints.tp \
 	thapi_tracepoints.tp \
+	btx_thapi.yaml \
 	command.rb \
 	meta_parameters.rb \
 	optparse_thapi.rb \

utils/btx_thapi.yaml

@@ -0,0 +1,27 @@
+:stream_classes:
+- :name: thapi_toggle
+  :default_clock_class: {}
+  :packet_context_field_class:
+    :type: structure
+    :members:
+    - :name: cpu_id
+      :field_class:
+        :type: integer_unsigned
+        :cast_type: uint64_t
+        :field_value_range: 32
+  :event_common_context_field_class:
+    :type: structure
+    :members:
+    - :name: vpid
+      :field_class:
+        :type: integer_signed
+        :field_value_range: 32
+        :cast_type: int
+    - :name: vtid
+      :field_class:
+        :type: integer_signed
+        :field_value_range: 32
+        :cast_type: int
+  :event_classes:
+  - :name: lttng_ust_toggle:start
+  - :name: lttng_ust_toggle:stop

utils/thapi_callbacks.c

@@ -0,0 +1,35 @@
+#include <metababel/metababel.h>
+
+static void init(void **data) { *data = calloc(1, sizeof(int)); }
+
+static void finalize(void *data) { free(data); }
+
+static void thapi_start_callback(void *btx_handle, void *push, long int cpuid,
+                                 int vpid, int vtid) {
+  *((int *)push) = 1;
+}
+
+static void thapi_stop_callback(void *btx_handle, void *push, long int cpuid,
+                                int vpid, int vtid) {
+  *((int *)push) = 0;
+}
+
+static void push_downstream(void *btx_handle, void *push,
+                            const bt_message *msg) {
+  if (*((int *)push) == 1)
+    btx_push_message(btx_handle, msg);
+  else
+    bt_message_put_ref(msg);
+}
+
+void btx_register_usr_callbacks(void *btx_handle) {
+  btx_register_callbacks_initialize_component(btx_handle, &init);
+  btx_register_callbacks_finalize_component(btx_handle, &finalize);
+
+  btx_register_callbacks_lttng_ust_toggle_start(btx_handle,
+                                                &thapi_start_callback);
+  btx_register_callbacks_lttng_ust_toggle_stop(btx_handle,
+                                               &thapi_stop_callback);
+
+  btx_register_on_downstream_message_callback(btx_handle, &push_downstream);
+}