build: remove dtrace probes

The existing probes, all two of them, cause a great deal of pain for
people trying to build libuv on Linux because of SystemTap's dtrace(1)
utilitity not understanding the -xnolibs flag.

We could hack around that but it's easier to just remove the probes:
they are largely useless and unused while still needing a lot of
supporting infrastructure.  This commit removes 200 lines of code
and configuration.

Refs joyent/libuv#1478.

.gitignore

@@ -34,9 +34,6 @@ vgcore.*
 Makefile
 Makefile.in
 
-# Generated by dtrace(1) when doing an in-tree build.
-/include/uv-dtrace.h
-
 # Generated by gyp for android
 *.target.mk
 

Makefile.am

@@ -307,46 +307,7 @@ libuv_la_CFLAGS += -D__EXTENSIONS__ -D_XOPEN_SOURCE=500
 libuv_la_SOURCES += src/unix/sunos.c
 endif
 
-if HAVE_DTRACE
-BUILT_SOURCES = include/uv-dtrace.h
-CLEANFILES += include/uv-dtrace.h
-if FREEBSD
-libuv_la_LDFLAGS += -lelf
-endif
-endif
-
-if DTRACE_NEEDS_OBJECTS
-libuv_la_SOURCES += src/unix/uv-dtrace.d
-libuv_la_DEPENDENCIES = src/unix/uv-dtrace.o
-libuv_la_LIBADD = uv-dtrace.lo
-CLEANFILES += src/unix/uv-dtrace.o src/unix/uv-dtrace.lo
-endif
-
 if HAVE_PKG_CONFIG
 pkgconfigdir = $(libdir)/pkgconfig
 pkgconfig_DATA = @PACKAGE_NAME@.pc
 endif
-
-if HAVE_DTRACE
-include/uv-dtrace.h: src/unix/uv-dtrace.d
-	$(AM_V_GEN)$(DTRACE) $(DTRACEFLAGS) -h -xnolibs -s $< -o $(top_srcdir)/$@
-endif
-
-if DTRACE_NEEDS_OBJECTS
-SUFFIXES = .d
-
-src/unix/uv-dtrace.o: src/unix/uv-dtrace.d ${libuv_la_OBJECTS}
-
-# It's ok to specify the output here, because we have 1 .d file, and we process
-# every created .o, most projects don't need to include more than one .d
-.d.o:
-	$(AM_V_GEN)$(DTRACE) $(DTRACEFLAGS) -G -o $(top_builddir)/uv-dtrace.o -s $< \
-		`find ${top_builddir}/src -name "*.o"`
-	$(AM_V_GEN)printf %s\\n \
-		'# ${top_builddir}/uv-dtrace.lo - a libtool object file' \
-		'# Generated by libtool (GNU libtool) 2.4' \
-		'# libtool wants a .lo not a .o' \
-		"pic_object='uv-dtrace.o'" \
-		"non_pic_object='uv-dtrace.o'" \
-	> ${top_builddir}/uv-dtrace.lo
-endif

configure.ac

@@ -50,7 +50,6 @@ AM_CONDITIONAL([NETBSD],   [AS_CASE([$host_os],[netbsd*],       [true], [false])
 AM_CONDITIONAL([OPENBSD],  [AS_CASE([$host_os],[openbsd*],      [true], [false])])
 AM_CONDITIONAL([SUNOS],    [AS_CASE([$host_os],[solaris*],      [true], [false])])
 AM_CONDITIONAL([WINNT],    [AS_CASE([$host_os],[mingw*],        [true], [false])])
-PANDORA_ENABLE_DTRACE
 AC_CHECK_PROG(PKG_CONFIG, pkg-config, yes)
 AM_CONDITIONAL([HAVE_PKG_CONFIG], [test "x$PKG_CONFIG" != "x"])
 AS_IF([test "x$PKG_CONFIG" != "x"], [

m4/.gitignore

@@ -1,5 +1,4 @@
 # Ignore libtoolize-generated files.
 *.m4
 !as_case.m4
-!dtrace.m4
+!libuv-check-flags.m4
-!libuv-check-flags.m4

m4/dtrace.m4

@@ -1,66 +0,0 @@
-dnl  Copyright (C) 2009 Sun Microsystems
-dnl This file is free software; Sun Microsystems
-dnl gives unlimited permission to copy and/or distribute it,
-dnl with or without modifications, as long as this notice is preserved.
-
-dnl ---------------------------------------------------------------------------
-dnl Macro: PANDORA_ENABLE_DTRACE
-dnl ---------------------------------------------------------------------------
-AC_DEFUN([PANDORA_ENABLE_DTRACE],[
-  AC_ARG_ENABLE([dtrace],
-    [AS_HELP_STRING([--disable-dtrace],
-            [enable DTrace USDT probes. @<:@default=yes@:>@])],
-    [ac_cv_enable_dtrace="$enableval"],
-    [ac_cv_enable_dtrace="yes"])
-
-  AS_IF([test "$ac_cv_enable_dtrace" = "yes"],[
-    AC_CHECK_PROGS([DTRACE], [dtrace])
-    AS_IF([test "x$ac_cv_prog_DTRACE" = "xdtrace"],[
-
-      AC_CACHE_CHECK([if dtrace works],[ac_cv_dtrace_works],[
-        cat >conftest.d <<_ACEOF
-provider Example {
-  probe increment(int);
-};
-_ACEOF
-        $DTRACE -h -o conftest.h -s conftest.d 2>/dev/zero
-        AS_IF([test $? -eq 0],[ac_cv_dtrace_works=yes],
-          [ac_cv_dtrace_works=no])
-        rm -f conftest.h conftest.d
-      ])
-      AS_IF([test "x$ac_cv_dtrace_works" = "xyes"],[
-        AC_DEFINE([HAVE_DTRACE], [1], [Enables DTRACE Support])
-        AC_CACHE_CHECK([if dtrace should instrument object files],
-          [ac_cv_dtrace_needs_objects],[
-            dnl DTrace on MacOSX does not use -G option
-            cat >conftest.d <<_ACEOF
-provider Example {
-  probe increment(int);
-};
-_ACEOF
-          cat > conftest.c <<_ACEOF
-#include "conftest.h"
-void foo() {
-  EXAMPLE_INCREMENT(1);
-}
-_ACEOF
-            $DTRACE -h -o conftest.h -s conftest.d 2>/dev/zero
-            $CC -c -o conftest.o conftest.c
-            $DTRACE -G -o conftest.d.o -s conftest.d conftest.o 2>/dev/zero
-            AS_IF([test $? -eq 0],[ac_cv_dtrace_needs_objects=yes],
-              [ac_cv_dtrace_needs_objects=no])
-            rm -f conftest.d.o conftest.d conftest.h conftest.o conftest.c
-        ])
-      ])
-      AC_SUBST(DTRACEFLAGS) dnl TODO: test for -G on OSX
-      ac_cv_have_dtrace=yes
-    ])])
-
-AM_CONDITIONAL([HAVE_DTRACE], [test "x$ac_cv_dtrace_works" = "xyes"])
-AM_CONDITIONAL([DTRACE_NEEDS_OBJECTS],
-               [test "x$ac_cv_dtrace_needs_objects" = "xyes"])
-
-])
-dnl ---------------------------------------------------------------------------
-dnl End Macro: PANDORA_ENABLE_DTRACE
-dnl ---------------------------------------------------------------------------

src/unix/core.c

@@ -310,8 +310,6 @@ int uv_run(uv_loop_t* loop, uv_run_mode mode) {
     uv__update_time(loop);
 
   while (r != 0 && loop->stop_flag == 0) {
-    UV_TICK_START(loop, mode);
-
     uv__update_time(loop);
     uv__run_timers(loop);
     uv__run_pending(loop);
@@ -340,7 +338,6 @@ int uv_run(uv_loop_t* loop, uv_run_mode mode) {
     }
 
     r = uv__loop_alive(loop);
-    UV_TICK_STOP(loop, mode);
 
     if (mode & (UV_RUN_ONCE | UV_RUN_NOWAIT))
       break;

src/unix/internal.h

@@ -306,12 +306,4 @@ UV_UNUSED(static char* uv__basename_r(const char* path)) {
   return s + 1;
 }
 
-
-#ifdef HAVE_DTRACE
-#include "uv-dtrace.h"
-#else
-#define UV_TICK_START(arg0, arg1)
-#define UV_TICK_STOP(arg0, arg1)
-#endif
-
 #endif /* UV_UNIX_INTERNAL_H_ */

uv.gyp

@@ -1,14 +1,4 @@
 {
-  'variables': {
-    'uv_use_dtrace%': 'false',
-    # uv_parent_path is the relative path to libuv in the parent project
-    # this is only relevant when dtrace is enabled and libuv is a child project
-    # as it's necessary to correctly locate the object files for post
-    # processing.
-    # XXX gyp is quite sensitive about paths with double / they don't normalize
-    'uv_parent_path': '/',
-  },
-
   'target_defaults': {
     'conditions': [
       ['OS != "win"', {
@@ -296,20 +286,6 @@
         ['uv_library=="shared_library"', {
           'defines': [ 'BUILDING_UV_SHARED=1' ]
         }],
-        # FIXME(bnoordhuis or tjfontaine) Unify this, it's extremely ugly.
-        ['uv_use_dtrace=="true"', {
-          'defines': [ 'HAVE_DTRACE=1' ],
-          'dependencies': [ 'uv_dtrace_header' ],
-          'include_dirs': [ '<(SHARED_INTERMEDIATE_DIR)' ],
-          'conditions': [
-            [ 'OS not in "mac linux"', {
-              'sources': [ 'src/unix/dtrace.c' ],
-            }],
-            [ 'OS=="linux"', {
-              'sources': [ '<(SHARED_INTERMEDIATE_DIR)/dtrace.o' ]
-            }],
-          ],
-        }],
       ]
     },
 
@@ -522,60 +498,5 @@
         },
       },
     },
-
-    {
-      'target_name': 'uv_dtrace_header',
-      'type': 'none',
-      'conditions': [
-        [ 'uv_use_dtrace=="true"', {
-          'actions': [
-            {
-              'action_name': 'uv_dtrace_header',
-              'inputs': [ 'src/unix/uv-dtrace.d' ],
-              'outputs': [ '<(SHARED_INTERMEDIATE_DIR)/uv-dtrace.h' ],
-              'action': [ 'dtrace', '-h', '-xnolibs', '-s', '<@(_inputs)',
-                '-o', '<@(_outputs)' ],
-            },
-          ],
-        }],
-      ],
-    },
-
-    # FIXME(bnoordhuis or tjfontaine) Unify this, it's extremely ugly.
-    {
-      'target_name': 'uv_dtrace_provider',
-      'type': 'none',
-      'conditions': [
-        [ 'uv_use_dtrace=="true" and OS not in "mac linux"', {
-          'actions': [
-            {
-              'action_name': 'uv_dtrace_o',
-              'inputs': [
-                'src/unix/uv-dtrace.d',
-                '<(PRODUCT_DIR)/obj.target/libuv<(uv_parent_path)src/unix/core.o',
-              ],
-              'outputs': [
-                '<(PRODUCT_DIR)/obj.target/libuv<(uv_parent_path)src/unix/dtrace.o',
-              ],
-              'action': [ 'dtrace', '-G', '-xnolibs', '-s', '<@(_inputs)',
-                '-o', '<@(_outputs)' ]
-            }
-          ]
-        }],
-        [ 'uv_use_dtrace=="true" and OS=="linux"', {
-          'actions': [
-            {
-              'action_name': 'uv_dtrace_o',
-              'inputs': [ 'src/unix/uv-dtrace.d' ],
-              'outputs': [ '<(SHARED_INTERMEDIATE_DIR)/dtrace.o' ],
-              'action': [
-                'dtrace', '-C', '-G', '-s', '<@(_inputs)', '-o', '<@(_outputs)'
-              ],
-            }
-          ]
-        }],
-      ]
-    },
-
   ]
 }