erts: Implement tracer modules

Add the possibility to use modules as trace data receivers. The functions
in the module have to be nifs as otherwise complex trace probes will be
very hard to handle (complex means trace probes for ports for example).

This commit changes the way that the ptab->tracer field works from always
being an immediate, to now be NIL if no tracer is present or else be
the tuple {TracerModule, TracerState} where TracerModule is an atom that
is later used to lookup the appropriate tracer callbacks to call and
TracerState is just passed to the tracer callback. The default process and
port tracers have been rewritten to use the new API.

This commit also changes the order which trace messages are delivered to the
potential tracer process. Any enif_send done in a tracer module may be delayed
indefinitely because of lock order issues. If a message is delayed any other
trace message send from that process is also delayed so that order is preserved
for each traced entity. This means that for some trace events (i.e. send/receive)
the events may come in an unintuitive order (receive before send) to the
trace receiver. Timestamps are taken when the trace message is generated so
trace messages from differented processes may arrive with the timestamp
out of order.

Both the erlang:trace and seq_trace:set_system_tracer accept the new tracer
module tracers and also the backwards compatible arguments.

OTP-10267

2 files changed, 24 insertions, 58 deletions

diff --git a/lib/runtime_tools/c_src/Makefile.in b/lib/runtime_tools/c_src/Makefile.in
index 58c12e0d88..70b48daf97 100644
--- a/lib/runtime_tools/c_src/Makefile.in
+++ b/lib/runtime_tools/c_src/Makefile.in
@@ -33,21 +33,18 @@ VSN=$(RUNTIME_TOOLS_VSN)
 # be set for that system only.
 # ----------------------------------------------------
 CC = $(DED_CC)
-CFLAGS = $(DED_CFLAGS)
+CFLAGS = $(DED_CFLAGS) -I./
 LD = $(DED_LD)
 SHELL = /bin/sh
 LIBS = $(DED_LIBS)
 LDFLAGS += $(DED_LDFLAGS)
 
-DTRACE_LIBNAME = dyntrace
+TRACE_LIBNAME = dyntrace trace_file_drv trace_ip_drv
 
 SYSINCLUDE = $(DED_SYS_INCLUDE)
 
 TRACE_DRV_INCLUDES = $(SYSINCLUDE)
 
-ALL_CFLAGS = $(CFLAGS) @DEFS@ $(TYPE_FLAGS) $(TRACE_DRV_INCLUDES) \
-	-I$(OBJDIR) -I$(ERL_TOP)/erts/emulator/$(TARGET)
-
 ifeq ($(TYPE),debug)
 TYPEMARKER = .debug
 TYPE_FLAGS = $(subst -O3,,$(subst -O2,,$(CFLAGS))) -DDEBUG @DEBUG_FLAGS@
@@ -61,6 +58,9 @@ TYPE_FLAGS = $(CFLAGS)
 endif
 endif
 
+ALL_CFLAGS = @DEFS@ $(TYPE_FLAGS) $(TRACE_DRV_INCLUDES) \
+	-I$(OBJDIR) -I$(ERL_TOP)/erts/emulator/$(TARGET)
+
 ROOTDIR = $(ERL_TOP)/lib
 PRIVDIR = ../priv
 LIBDIR = $(PRIVDIR)/lib/$(TARGET)
@@ -74,37 +74,16 @@ RELSYSDIR = $(RELEASE_PATH)/lib/runtime_tools-$(VSN)
 # ----------------------------------------------------
 # Misc Macros
 # ----------------------------------------------------
-before_DTrace_OBJS = $(OBJDIR)/dyntrace$(TYPEMARKER).o
-## NIF_MAKEFILE = $(PRIVDIR)/Makefile
 
-# Higher-level makefiles says that we can only compile on UNIX flavors
-NIF_LIB = $(LIBDIR)/dyntrace$(TYPEMARKER).@DED_EXT@
+TRACE_LIBS = $(foreach LIB, $(TRACE_LIBNAME), $(LIBDIR)/$(LIB)$(TYPEMARKER).@DED_EXT@)
 
-ifeq ($(HOST_OS),)
-HOST_OS := $(shell $(ERL_TOP)/erts/autoconf/config.guess)
-endif
-
-TRACE_IP_DRV_OBJS = \
-	$(OBJDIR)/trace_ip_drv.o
-
-TRACE_FILE_DRV_OBJS = \
-	$(OBJDIR)/trace_file_drv.o
-
-ifeq ($(findstring win32,$(TARGET)), win32)
-SOLIBS = $(LIBDIR)/trace_ip_drv.dll $(LIBDIR)/trace_file_drv.dll
-LN=cp
-else
-SOLIBS = $(LIBDIR)/trace_ip_drv.so $(LIBDIR)/trace_file_drv.so
-endif
 # ----------------------------------------------------
 # Targets
 # ----------------------------------------------------
 
 _create_dirs := $(shell mkdir -p $(OBJDIR) $(LIBDIR))
 
-debug opt valgrind: $(SOLIBS) $(OBJDIR) $(LIBDIR) $(NIF_LIB)
-
-DYNTRACE_OBJS = $(before_DTrace_OBJS)
+debug opt valgrind: $(SOLIBS) $(OBJDIR) $(LIBDIR) $(TRACE_LIBS)
 
 $(OBJDIR):
 	-@mkdir -p $(OBJDIR)
@@ -112,50 +91,26 @@ $(OBJDIR):
 $(LIBDIR):
 	-@mkdir -p $(LIBDIR)
 
-$(OBJDIR)/dyntrace$(TYPEMARKER).o: dyntrace.c
-	$(V_at)$(INSTALL_DIR) $(OBJDIR)
-	$(V_CC) -c -o $@ $(ALL_CFLAGS) $<
-
-$(NIF_LIB): $(DYNTRACE_OBJS)
-	$(V_at)$(INSTALL_DIR) $(LIBDIR)
-	$(V_LD) $(LDFLAGS) -o $@ $^ $(LDLIBS)
-
-$(OBJDIR)/%.o: %.c
+$(OBJDIR)/%$(TYPEMARKER).o: %.c
 	$(V_CC) -c -o $@ $(ALL_CFLAGS) $<
 
-$(LIBDIR)/trace_ip_drv.so: $(TRACE_IP_DRV_OBJS)
-	$(V_LD) $(LDFLAGS) -o $@ $^ -lc $(LIBS)
-
-$(LIBDIR)/trace_file_drv.so: $(TRACE_FILE_DRV_OBJS)
-	$(V_LD) $(LDFLAGS) -o $@ $^ -lc $(LIBS)
-
-$(LIBDIR)/trace_ip_drv.dll: $(TRACE_IP_DRV_OBJS)
-	$(V_LD) $(LDFLAGS) -o $@ $^ $(LIBS)
-$(LIBDIR)/trace_file_drv.dll: $(TRACE_FILE_DRV_OBJS)
+$(LIBDIR)/%$(TYPEMARKER).@DED_EXT@: $(OBJDIR)/%$(TYPEMARKER).o
 	$(V_LD) $(LDFLAGS) -o $@ $^ $(LIBS)
 
 clean:
-	rm -f $(SOLIBS) $(TRACE_IP_DRV_OBJS) $(TRACE_FILE_DRV_OBJS)
-	rm -f $(LIBDIR)/dyntrace.@DED_EXT@
-	rm -f $(LIBDIR)/dyntrace.debug.@DED_EXT@
-	rm -f $(LIBDIR)/dyntrace.valgrind.@DED_EXT@
-	rm -f $(OBJDIR)/dyntrace.o
-	rm -f $(OBJDIR)/dyntrace.debug.o
-	rm -f $(OBJDIR)/dyntrace.valgrind.o
+	rm -f $(TRACE_LIBS)
 	rm -f core *~
 
 docs:
 
 # ----------------------------------------------------
 # Release Target
-# ---------------------------------------------------- 
+# ----------------------------------------------------
 include $(ERL_TOP)/make/otp_release_targets.mk
 
 release_spec: opt
-	$(INSTALL_DIR) "$(RELSYSDIR)/priv/obj"
 	$(INSTALL_DIR) "$(RELSYSDIR)/priv/lib"
-	$(INSTALL_PROGRAM) $(DYNTRACE_OBJS) "$(RELSYSDIR)/priv/obj"
-	$(INSTALL_PROGRAM) $(NIF_LIB) $(SOLIBS) "$(RELSYSDIR)/priv/lib"
+	$(INSTALL_PROGRAM) $(TRACE_LIBS) "$(RELSYSDIR)/priv/lib"
 
 release_docs_spec:
 
diff --git a/lib/runtime_tools/c_src/trace_file_drv.c b/lib/runtime_tools/c_src/trace_file_drv.c
index 703766c188..e7fd5968c1 100644
--- a/lib/runtime_tools/c_src/trace_file_drv.c
+++ b/lib/runtime_tools/c_src/trace_file_drv.c
@@ -172,6 +172,7 @@ static ErlDrvData trace_file_start(ErlDrvPort port, char *buff);
 static void trace_file_stop(ErlDrvData handle);
 static void trace_file_output(ErlDrvData handle, char *buff,
 			      ErlDrvSizeT bufflen);
+static void trace_file_outputv(ErlDrvData handle, ErlIOVec *ev);
 static void trace_file_finish(void);
 static ErlDrvSSizeT trace_file_control(ErlDrvData handle,
 				      unsigned int command, 
@@ -214,7 +215,7 @@ ErlDrvEntry trace_file_driver_entry = {
     NULL,                  /* void * that is not used (BC) */
     trace_file_control,    /* F_PTR control, port_control callback */
     trace_file_timeout,    /* F_PTR timeout, driver_set_timer callback */
-    NULL,                  /* F_PTR outputv, reserved */
+    trace_file_outputv,    /* F_PTR outputv, reserved */
     NULL, /* ready_async */
     NULL, /* flush */
     NULL, /* call */
@@ -363,6 +364,16 @@ static void trace_file_stop(ErlDrvData handle)
 /*
 ** Data sent from erlang to port.
 */
+static void trace_file_outputv(ErlDrvData handle, ErlIOVec *ev)
+{
+    int i;
+    for (i = 0; i < ev->vsize; i++) {
+        if (ev->iov[i].iov_len)
+            trace_file_output(handle, ev->iov[i].iov_base,
+                              ev->iov[i].iov_len);
+    }
+}
+
 static void trace_file_output(ErlDrvData handle, char *buff,
 			      ErlDrvSizeT bufflen)
 {