* thread.c (rb_thread_atfork_internal): reinitialize global lock

  at fork to get rid of deadlock.  based on the patch from Hongli
  Lai in [ruby-core:26783].  [ruby-core:26361]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@25842 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 26 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index bfef35165c..c63d421aea 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Nov 18 18:25:09 2009  Nobuyoshi Nakada  <[email protected]>
+
+	* thread.c (rb_thread_atfork_internal): reinitialize global lock
+	  at fork to get rid of deadlock.  based on the patch from Hongli
+	  Lai in [ruby-core:26783].  [ruby-core:26361]
+
 Wed Nov 18 17:48:22 2009  Nobuyoshi Nakada  <[email protected]>
 
 	* thread.c (terminate_atfork_i): all mutex locks by other threads
diff --git a/bootstraptest/test_thread.rb b/bootstraptest/test_thread.rb
index 4b715a1545..e463626167 100644
--- a/bootstraptest/test_thread.rb
+++ b/bootstraptest/test_thread.rb
@@ -408,3 +408,22 @@ assert_equal 'ok', %{
   require "./zzz.rb"
   $result
 }
+
+assert_finish 3, %q{
+  require 'thread'
+
+  lock = Mutex.new
+  cond = ConditionVariable.new
+  t = Thread.new do
+    lock.synchronize do
+      cond.wait(lock)
+    end
+  end
+
+  pid = fork do
+    # Child
+    STDOUT.write "This is the child process.\n"
+    STDOUT.write "Child process exiting.\n"
+  end
+  Process.waitpid(pid)
+}, '[ruby-core:26361]'
diff --git a/thread.c b/thread.c
index 5caf1da4ff..9c6ec5b73d 100644
--- a/thread.c
+++ b/thread.c
@@ -2710,6 +2710,7 @@ rb_thread_atfork_internal(int (*atfork)(st_data_t, st_data_t, st_data_t))
     VALUE thval = th->self;
     vm->main_thread = th;
 
+    native_mutex_reinitialize_atfork(&th->vm->global_vm_lock);
     st_foreach(vm->living_threads, atfork, (st_data_t)th);
     st_clear(vm->living_threads);
     st_insert(vm->living_threads, thval, (st_data_t)th->thread_id);