From 27251312111b7e25e347773e5777ee6072f9289b Mon Sep 17 00:00:00 2001 From: nagachika Date: Sat, 8 Jul 2017 02:21:36 +0000 Subject: [PATCH] merge revision(s) 58284,58812,59028: [Backport #13632] 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 --- test/ruby/test_io.rb | 22 ++++++++++++++++++++++ thread.c | 36 +++++++++++++++++++++++++----------- vm.c | 1 - vm_core.h | 6 +++--- 4 files changed, 50 insertions(+), 15 deletions(-) diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb index 61dfba318042..034dac570ce4 100644 --- a/test/ruby/test_io.rb +++ b/test/ruby/test_io.rb @@ -2809,6 +2809,28 @@ def test_cross_thread_close_stdio end; end + def test_single_exception_on_close + a = [] + t = [] + 10.times do + r, w = IO.pipe + a << [r, w] + t << Thread.new do + while r.gets + end rescue IOError + Thread.current.pending_interrupt? + end + end + a.each do |r, w| + w.write -"\n" + w.close + r.close + end + t.each do |th| + assert_equal false, th.value, '[ruby-core:81581] [Bug #13632]' + end + end + def test_open_mode feature4742 = "[ruby-core:36338]" bug6055 = '[ruby-dev:45268]' diff --git a/thread.c b/thread.c index 7391cf96d284..2691fd835de4 100644 --- a/thread.c +++ b/thread.c @@ -95,7 +95,11 @@ static int rb_threadptr_pending_interrupt_empty_p(rb_thread_t *th); #define eTerminateSignal INT2FIX(1) static volatile int system_working = 1; -#define closed_stream_error GET_VM()->special_exceptions[ruby_error_closed_stream] +struct waiting_fd { + struct list_node wfd_node; /* <=> vm.waiting_fds */ + rb_thread_t *th; + int fd; +}; inline static void st_delete_wrap(st_table *table, st_data_t key) @@ -1310,7 +1314,6 @@ call_without_gvl(void *(*func)(void *), void *data1, rb_thread_t *th = GET_THREAD(); int saved_errno = 0; - th->waiting_fd = -1; if (ubf == RUBY_UBF_IO || ubf == RUBY_UBF_PROCESS) { ubf = ubf_select; data2 = th; @@ -1433,11 +1436,15 @@ VALUE rb_thread_io_blocking_region(rb_blocking_function_t *func, void *data1, int fd) { volatile VALUE val = Qundef; /* shouldn't be used */ + rb_vm_t *vm = GET_VM(); rb_thread_t *th = GET_THREAD(); volatile int saved_errno = 0; int state; + struct waiting_fd wfd; - th->waiting_fd = fd; + wfd.fd = fd; + wfd.th = th; + list_add(&vm->waiting_fds, &wfd.wfd_node); TH_PUSH_TAG(th); if ((state = EXEC_TAG()) == 0) { @@ -1448,8 +1455,8 @@ rb_thread_io_blocking_region(rb_blocking_function_t *func, void *data1, int fd) } TH_POP_TAG(); - /* clear waiting_fd anytime */ - th->waiting_fd = -1; + /* must be deleted before jump */ + list_del(&wfd.wfd_node); if (state) { TH_JUMP_TAG(th, state); @@ -2195,16 +2202,23 @@ int rb_notify_fd_close(int fd) { rb_vm_t *vm = GET_THREAD()->vm; - rb_thread_t *th = 0; + struct waiting_fd *wfd = 0; int busy; busy = 0; - list_for_each(&vm->living_threads, th, vmlt_node) { - if (th->waiting_fd == fd) { - VALUE err = th->vm->special_exceptions[ruby_error_closed_stream]; + list_for_each(&vm->waiting_fds, wfd, wfd_node) { + if (wfd->fd == fd) { + rb_thread_t *th = wfd->th; + VALUE err; + + busy = 1; + if (!th) { + continue; + } + wfd->th = 0; + err = th->vm->special_exceptions[ruby_error_stream_closed]; rb_threadptr_pending_interrupt_enque(th, err); rb_threadptr_interrupt(th); - busy = 1; } } return busy; @@ -4839,7 +4853,7 @@ Init_Thread(void) rb_define_method(rb_cThread, "name=", rb_thread_setname, 1); rb_define_method(rb_cThread, "inspect", rb_thread_inspect, 0); - rb_vm_register_special_exception(ruby_error_closed_stream, rb_eIOError, "stream closed"); + rb_vm_register_special_exception(ruby_error_stream_closed, rb_eIOError, "stream closed"); cThGroup = rb_define_class("ThreadGroup", rb_cObject); rb_define_alloc_func(cThGroup, thgroup_s_alloc); diff --git a/vm.c b/vm.c index 0544bcc4e573..c8ed39ad1e47 100644 --- a/vm.c +++ b/vm.c @@ -2477,7 +2477,6 @@ th_init(rb_thread_t *th, VALUE self) th->status = THREAD_RUNNABLE; th->errinfo = Qnil; th->last_status = Qnil; - th->waiting_fd = -1; th->root_svar = Qfalse; th->local_storage_recursive_hash = Qnil; th->local_storage_recursive_hash_for_trace = Qnil; diff --git a/vm_core.h b/vm_core.h index d0385d219f82..8e2b93d8e9b2 100644 --- a/vm_core.h +++ b/vm_core.h @@ -427,7 +427,7 @@ enum ruby_special_exceptions { ruby_error_reenter, ruby_error_nomemory, ruby_error_sysstack, - ruby_error_closed_stream, + ruby_error_stream_closed, ruby_special_error_count }; @@ -490,6 +490,7 @@ typedef struct rb_vm_struct { struct rb_thread_struct *main_thread; struct rb_thread_struct *running_thread; + struct list_head waiting_fds; /* <=> struct waiting_fd */ struct list_head living_threads; size_t living_thread_num; VALUE thgroup_default; @@ -712,8 +713,6 @@ typedef struct rb_thread_struct { /* passing state */ int state; - int waiting_fd; - /* for rb_iterate */ VALUE passed_block_handler; @@ -1445,6 +1444,7 @@ void rb_thread_wakeup_timer_thread(void); static inline void rb_vm_living_threads_init(rb_vm_t *vm) { + list_head_init(&vm->waiting_fds); list_head_init(&vm->living_threads); vm->living_thread_num = 0; }