[UNFINISHED] Fix handling of have_kernel_resources on Mach/Hurd.

<http://lists.gnu.org/archive/html/bug-hurd/2009-04/msg00028.html>

Further comments by Neal:

<neal> do you want a reply on the libpthread one inline?
<neal> the short answer is: yes, that's a bug
<neal> unfortunately, your fix is not enough
<neal> the predicate controls two resources: the wakeup port and the thread
  itself
<tschwinge> Oh, right, I see.
<neal> also, there may be a race:
<neal> set the predicate to free, then kill the thread
<neal> that's not so good
<neal> so a proper solution requires a bit more thought
<tschwinge> I think I wondered about that as well.  But isn't there the same
  problem with Viengoos?
<neal> it is difficult as cleanly committing suicide is hard :-)
<neal> could be
<neal> on viengoos, I don't actually deallocate the thread in pt-thread-halt.c
<neal> I just call suspend
<neal> the thread is only deallocated in pt-thread-dealloc.c

1 files changed, 17 insertions, 2 deletions

diff --git a/sysdeps/mach/pt-thread-halt.c b/sysdeps/mach/pt-thread-halt.c
index 973cde1..a9c3858 100644
--- a/sysdeps/mach/pt-thread-halt.c
+++ b/sysdeps/mach/pt-thread-halt.c
@@ -32,6 +32,21 @@
 void
 __pthread_thread_halt (struct __pthread *thread)
 {
-  error_t err = __thread_terminate (thread->kernel_thread);
-  assert_perror (err);
+  if (thread->have_kernel_resources)
+    {
+      if (thread == _pthread_self ())
+	{
+	  while (1)
+	    {
+	      error_t err = __thread_suspend (thread->kernel_thread);
+	      assert_perror (err);
+	      assert (! "Failed to suspend self.");
+	    }
+	}
+      else
+	{
+	  error_t err = __thread_terminate (thread->kernel_thread);
+	  assert_perror (err);
+	}
+    }
 }