thread_pthread.c: fix deadlock on test_thread.rb::test_signal_at_join
Fixes: r64575 ("avoid lock ping-pong in do_gvl_timer & ubf_select")
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64579 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
thread_pthread.c: fix deadlock on test_thread.rb::test_signal_at_join
Fixes: r64575 ("avoid lock ping-pong in do_gvl_timer & ubf_select")
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64579 b2dd03c8-39d4-4d8f-98ff-823fe69b080e