[Mono-dev] Mono preview 2.0 binary and DTrace

[Boris Dušek]

Hi Andreas,

On Sat, Aug 2, 2008 at 6:30 PM, Andreas Färber <andreas.faerber at web.de> wrote:
>> I grabbed the Mono Preview 2.0 installer for OS X and wanted to test
>> new DTrace probes mentioned in Release Notes[1], but it did not work.
>
> Just to be sure, how did you test? As described in mono's man page?

With the same command that worked with mono that I compiled myself.
(with one difference - I used '/path/to/mono' for customly compiled
mono since my install prefix binary dir was not in $PATH):

boris at Pioneer:~/Documents/dev/mono/usr/bin$ sudo dtrace -P
mono'$target' -l -c mono
   ID   PROVIDER            MODULE                          FUNCTION NAME
dtrace: failed to match mono3618:::: No probe matches description

boris at Pioneer:~/Documents/dev/mono/usr/bin$ sudo dtrace -P
mono'$target' -l -c ./mono
   ID   PROVIDER            MODULE                          FUNCTION NAME
20188   mono3620              mono                   mono_gc_collect gc-begin
20189   mono3620              mono                   mono_gc_collect gc-end
21858   mono3620              mono               mini_method_compile
method-compile-begin
21859   mono3620              mono               mini_method_compile
method-compile-end
21860   mono3620              mono                         mini_init
ves-init-begin
21861   mono3620              mono                         mini_init
ves-init-end

btw. while we are at it, is it already possible now or do you plan to
add jstack support (so that the names of ".NET functions" appear
instead of addresses of frames for the part inside mono runtime?)

right now, with this Hello World program:

class Test {
    public static void Main(string[] args) {
        System.Console.WriteLine("Hello from C#");
    }
}

and this tracing script (tracing usermode stack at every write syscall):

syscall::write:entry
/pid == $target/
{
    trace(arg0);
    jstack();
}

I get this output which makes me believe it's either not implemented
or I am doing something wrong (both writes are to fd 1 = stderr):

boris at Pioneer:~/Documents/dev/mono/usr/bin$
DYLD_LIBRARY_PATH=`pwd`/../lib sudo dtrace -s tracemono.d -c './mono
/Users/boris/Test.exe'
dtrace: script 'tracemono.d' matched 1 probe
Hello from C#
dtrace: pid 1528 has exited
CPU     ID                    FUNCTION:NAME
  1  17600                      write:entry                 1
              libSystem.B.dylib`write$UNIX2003+0xa
              mono`ves_icall_System_IO_MonoIO_Write+0x66
              0x7d6084
              0x7d5d60
              0x7d5bae
              0x7d5ae6
              0x7cc8cd
              0x7d4ed8
              0x7d4e6e
              0x7d4df8
              0x7d4db6
              0x7ca289
              0x7ca24b
              0x7ca1ce
              mono`mono_runtime_exec_main+0xfe
              mono`mono_runtime_run_main+0x153
              mono`mono_main+0x1360
              mono`start+0x36
              0x2

  1  17600                      write:entry                 1
              libSystem.B.dylib`write$UNIX2003+0xa
              mono`ves_icall_System_IO_MonoIO_Write+0x66
              0x7d6084
              0x7d5d60
              0x7d5bae
              0x7d5ae6
              0x7cc8cd
              0x7d63bf
              0x7d61bd
              0x7d614e
              0x7d6128
              0x7d4e0a
              0x7d4db6
              0x7ca289
              0x7ca24b
              0x7ca1ce
              mono`mono_runtime_exec_main+0xfe
              mono`mono_runtime_run_main+0x153
              mono`mono_main+0x1360
              mono`start+0x36
              0x2

Tracing Java in this way yields empty trace, so probably it's me doing
something stupid.

Thanks,
Boris