git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@66975 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	cont.c: set th->root_fiber to current fiber at fork

	Otherwise, th->root_fiber can point to an invalid Fiber,
	because Fibers do not live across fork.  So consider
	whatever Fiber is running the root fiber.

	[ruby-core:88723] [Bug #15041]

	cont.c (rb_fiber_atfork): th->root_fiber may not exist

	Otherwise, bootstraptest/test_fork.rb fails with -DVM_CHECK_MODE=2

	[Bug #15041]

	Fixes: r64589 "cont.c: set th->root_fiber to current fiber at fork"

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@66968 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	thread.c (do_select): fix leak on exception

	When do_select is interrupted and raise happens from
	RUBY_VM_CHECK_INTS_BLOCKING, the original FD sets we copied
	do not get freed, leading to a memory leak.  Wrap up all the
	FD sets into a Ruby object to ensure the GC can release an
	allocations made for rb_fdset_t.

	This leak existed since Ruby 2.0.0 (r36430)

	[Bug #14929]

	increase timeout seconds.
	* test/ruby/test_io.rb (test_select_leak): increase timeout seconds
	  to pass this test on a high-load machine.


	60 sec is not enough at all


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@64561 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	thread.c: deadlock in backtrace

	* thread.c (unblock_function_set): check interrupts just once
	  during raising exceptions, as they are deferred since r16651.
	  [ruby-core:85939] [Bug #14577]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@62917 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	thread.c: report then abort

	* thread.c (thread_start_func_2): report then abort on exception,
	  if both are set.  [ruby-core:79280] [Bug #13163]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@62711 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	release VM stack properly.

	* cont.c: r55766 change the handling method of Fiber's VM stack.
	  Resumed Fiber points NULL as VM stack and running Thread has
	  responsibility to manage it (marking and releasing).

	  However, thread_start_func_2()@thread.c and thread_free()@vm.c
	  doesn't free the VM stack if corresponding root Fiber is exist.
	  This causes memory leak. [Bug #13772]

	* cont.c (root_fiber_alloc): fib->cont.saved_thread.ec.stack should be NULL
	  because running thread has responsibility to manage this stack.

	* vm.c (rb_thread_recycle_stack_release): assert given stack is not NULL
	  (callers should care it).

	fix stack storing for root fibers.

	* cont.c (root_fiber_alloc): this function is called by fiber_current()
	  and fiber_store(). fiber_current() should clear VM stack information
	  in a fiber data because runnning thread knows stack information and has
	  responsibility to manage it. However fiber_store() requires to remain
	  VM stack information in a fiber data because the responsibility to manage
	  VM stack is moved to the Fiber from the Thread (and switch to another
	  fiber).

	* cont.c (root_fiber_alloc): save thread's fiber and root_fiber information.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@59516 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	thread.c: avoid busy looping on rb_thread_fd_close

	We no longer use it this function, but extensions do, and
	we need to ensure it continues to work for them.

	* thread.c (rb_thread_fd_close): schedule other threads in loop
	* ext/-test-/thread_fd_close/thread_fd_close.c: new file
	* ext/-test-/thread_fd_close/depend: ditto
	* ext/-test-/thread_fd_close/extconf.rb: ditto
	* test/-ext-/thread_fd_close/test_thread_fd_close.rb: new test
	* properties.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@59295 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	vm_core.h: ruby_error_stream_closed

	* vm_core.h (ruby_special_exceptions): renamed
	  ruby_error_closed_stream as ruby_error_stream_closed, like the
	  message.
	speed up IO#close with many threads

	Today, it increases IO#close performance with many threads:

	  Execution time (sec)
	  name            trunk   after
	  vm_thread_close 4.276   3.018

	  Speedup ratio: compare with the result of `trunk' (greater is better)
	  name            after
	  vm_thread_close 1.417

	This speedup comes because rb_notify_fd_close only scans threads
	inside rb_thread_io_blocking_region, not all threads in the VM.

	In the future, this type data structure may allow us to notify
	waiters of multiple FDs on a single thread (when using
	Fibers).

	* thread.c (struct waiting_fd): declare
	  (rb_thread_io_blocking_region): use on-stack list waiter
	  (rb_notify_fd_close): walk vm->waiting_fds instead
	  (call_without_gvl): remove old field setting
	  (th_init): ditto
	* vm_core.h (typedef struct rb_vm_struct): add waiting_fds list
	* (typedef struct rb_thread_struct): remove waiting_fd field
	  (rb_vm_living_threads_init): initialize waiting_fds list

	I am now kicking myself for not thinking about this 3 years ago
	when I introduced ccan/list in [Feature #9632] to optimize this
	same function :<
	IO#close: do not enqueue redundant interrupts (take #2)

	Enqueuing multiple errors for one event causes spurious errors
	down the line, as reported by Nikolay Vashchenko in
	https://bugs.ruby-lang.org/issues/13632

	This should fix bad interactions with test_race_gets_and_close
	in test/ruby/test_io.rb since we ensure rb_notify_fd_close
	continues returning the busy flag after enqueuing the interrupt.

	Backporting changes to 2.4 and earlier releases will be more
	challenging...

	* thread.c (rb_notify_fd_close): do not enqueue multiple interrupts
	  [ruby-core:81581] [Bug #13632]
	* test/ruby/test_io.rb (test_single_exception_on_close):
	  new test based on script from Nikolay

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@59286 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	thread.c: thread_do_start

	* thread.c (thread_do_start): extract from a macro in
	  thread_start_func_2 for debugger.
	thread.c: Thread.start with Symbol

	* thread.c (thread_do_start): fix segfault at start with Symbol.
	  proc created by Symbol#to_proc does not have environment unless
	  using refinements.  [ruby-core:80147] [Bug #13313]
	Fiber also has same issue. [Bug #13313]

	* thread.c (rb_vm_proc_local_ep): added.

	* cont.c (rb_fiber_start): use rb_vm_proc_local_ep().


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@58003 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	thread.c: rb_thread_fd_close [ci skip]

	* thread.c (rb_thread_fd_close): re-define only for abi-check,
	  abort if called.  [ruby-core:80078] [Bug #13304]
	thread.c: rb_thread_fd_close [ci skip]

	* thread.c (rb_thread_fd_close): remove deprecated. a couple of
	  external libraries used it.  [ruby-core:80078] [Bug #13304]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@57959 b2dd03c8-39d4-4d8f-98ff-823fe69b080e