rename thread internal naming

Now GVL is not process *Global* so this try to use another words. * `rb_global_vm_lock_t` -> `struct rb_thread_sched` * `gvl->owner` -> `sched->running` * `gvl->waitq` -> `sched->readyq` * `rb_gvl_init` -> `rb_thread_sched_init` * `gvl_destroy` -> `rb_thread_sched_destroy` * `gvl_acquire` -> `thread_sched_to_running` # waiting -> ready -> running * `gvl_release` -> `thread_sched_to_waiting` # running -> waiting * `gvl_yield` -> `thread_sched_yield` * `GVL_UNLOCK_BEGIN` -> `THREAD_BLOCKING_BEGIN` * `GVL_UNLOCK_END` -> `THREAD_BLOCKING_END` * removed * `rb_ractor_gvl` * `rb_vm_gvl_destroy` (not used) There are GVL functions such as `rb_thread_call_without_gvl()` yet but I don't have good name to replace them. Maybe GVL stands for "Greate Valuable Lock" or something like that.
author: Koichi Sasada <[email protected]> 2022-04-17 03:40:23 +0900
committer: Koichi Sasada <[email protected]> 2022-04-22 07:54:09 +0900
commit: 1c4fc0241d125879e1e5169f267f26637772f3a7 ()
tree: d23704a9fc31fe8bfb29835ce0bdae3dc278b513 /thread_pthread.c
parent: cb02324c4e5c7aae0add0a5c4e5adbf637d9acb0 (diff)
1 files changed, 145 insertions, 121 deletions
@@ -176,7 +176,6 @@ static const rb_hrtime_t *sigwait_timeout(rb_thread_t *, int sigwait_fd,
 int *drained_p);
 static void ubf_timer_disarm(void);
 static void threadptr_trap_interrupt(rb_thread_t *);
-static void clear_thread_cache_altstack(void);
 static void ubf_wakeup_all_threads(void);
 static int ubf_threads_empty(void);
@@ -220,17 +219,18 @@ static rb_hrtime_t native_cond_timeout(rb_nativethread_cond_t *, rb_hrtime_t);
 static int native_cond_timedwait(rb_nativethread_cond_t *cond, pthread_mutex_t *mutex, const rb_hrtime_t *abs);
 /*
- * Designate the next gvl.timer thread, favor the last thread in
- * the waitq since it will be in waitq longest
 */
 static int
-designate_timer_thread(rb_global_vm_lock_t *gvl)
 {
 native_thread_data_t *last;
- last = ccan_list_tail(&gvl->waitq, native_thread_data_t, node.ubf);
 if (last) {
- rb_native_cond_signal(&last->cond.gvlq);
 return TRUE;
 }
 return FALSE;
@@ -241,21 +241,21 @@ designate_timer_thread(rb_global_vm_lock_t *gvl)
 * periodically. Continue on old timeout if it expired.
 */
 static void
-do_gvl_timer(rb_global_vm_lock_t *gvl, rb_thread_t *th)
 {
 rb_vm_t *vm = GET_VM();
 static rb_hrtime_t abs;
 native_thread_data_t *nd = &th->native_thread_data;
- gvl->timer = th;
 /* take over wakeups from UBF_TIMER */
 ubf_timer_disarm();
- if (gvl->timer_err == ETIMEDOUT) {
- abs = native_cond_timeout(&nd->cond.gvlq, TIME_QUANTUM_NSEC);
 }
- gvl->timer_err = native_cond_timedwait(&nd->cond.gvlq, &gvl->lock, &abs);
 ubf_wakeup_all_threads();
 ruby_sigchld_handler(vm);
@@ -273,80 +273,92 @@ do_gvl_timer(rb_global_vm_lock_t *gvl, rb_thread_t *th)
 * Timeslice. Warning: the process may fork while this
 * thread is contending for GVL:
 */
- if (gvl->owner) {
- // strictly speaking, accessing "gvl->owner" is not thread-safe
- RUBY_VM_SET_TIMER_INTERRUPT(gvl->owner->ec);
 }
- gvl->timer = 0;
 }
 static void
-gvl_acquire_common(rb_global_vm_lock_t *gvl, rb_thread_t *th)
 {
- if (gvl->owner) {
 native_thread_data_t *nd = &th->native_thread_data;
 VM_ASSERT(th->unblock.func == 0 &&
- "we must not be in ubf_list and GVL waitq at the same time");
- ccan_list_add_tail(&gvl->waitq, &nd->node.gvl);
 do {
- if (!gvl->timer) {
- do_gvl_timer(gvl, th);
 }
 else {
- rb_native_cond_wait(&nd->cond.gvlq, &gvl->lock);
 }
- } while (gvl->owner);
- ccan_list_del_init(&nd->node.gvl);
- if (gvl->need_yield) {
- gvl->need_yield = 0;
- rb_native_cond_signal(&gvl->switch_cond);
 }
 }
 else { /* reset timer if uncontended */
- gvl->timer_err = ETIMEDOUT;
 }
- gvl->owner = th;
- if (!gvl->timer) {
- if (!designate_timer_thread(gvl) && !ubf_threads_empty()) {
 rb_thread_wakeup_timer_thread(-1);
 }
 }
 }
 static void
-gvl_acquire(rb_global_vm_lock_t *gvl, rb_thread_t *th)
 {
- rb_native_mutex_lock(&gvl->lock);
- gvl_acquire_common(gvl, th);
- rb_native_mutex_unlock(&gvl->lock);
 }
 static const native_thread_data_t *
-gvl_release_common(rb_global_vm_lock_t *gvl)
 {
 native_thread_data_t *next;
- gvl->owner = 0;
- next = ccan_list_top(&gvl->waitq, native_thread_data_t, node.gvl);
- if (next) rb_native_cond_signal(&next->cond.gvlq);
 return next;
 }
 static void
-gvl_release(rb_global_vm_lock_t *gvl)
 {
- rb_native_mutex_lock(&gvl->lock);
- gvl_release_common(gvl);
- rb_native_mutex_unlock(&gvl->lock);
 }
 static void
-gvl_yield(rb_global_vm_lock_t *gvl, rb_thread_t *th)
 {
 const native_thread_data_t *next;
@@ -355,49 +367,54 @@ gvl_yield(rb_global_vm_lock_t *gvl, rb_thread_t *th)
 * (perhaps looping in io_close_fptr) so we kick them:
 */
 ubf_wakeup_all_threads();
- rb_native_mutex_lock(&gvl->lock);
- next = gvl_release_common(gvl);
 /* An another thread is processing GVL yield. */
- if (UNLIKELY(gvl->wait_yield)) {
- while (gvl->wait_yield)
- rb_native_cond_wait(&gvl->switch_wait_cond, &gvl->lock);
 }
 else if (next) {
 /* Wait until another thread task takes GVL. */
- gvl->need_yield = 1;
- gvl->wait_yield = 1;
- while (gvl->need_yield)
- rb_native_cond_wait(&gvl->switch_cond, &gvl->lock);
- gvl->wait_yield = 0;
- rb_native_cond_broadcast(&gvl->switch_wait_cond);
 }
 else {
- rb_native_mutex_unlock(&gvl->lock);
 native_thread_yield();
- rb_native_mutex_lock(&gvl->lock);
- rb_native_cond_broadcast(&gvl->switch_wait_cond);
 }
- gvl_acquire_common(gvl, th);
- rb_native_mutex_unlock(&gvl->lock);
 }
 void
-rb_gvl_init(rb_global_vm_lock_t *gvl)
 {
- rb_native_mutex_initialize(&gvl->lock);
- rb_native_cond_initialize(&gvl->switch_cond);
- rb_native_cond_initialize(&gvl->switch_wait_cond);
- ccan_list_head_init(&gvl->waitq);
- gvl->owner = 0;
- gvl->timer = 0;
- gvl->timer_err = ETIMEDOUT;
- gvl->need_yield = 0;
- gvl->wait_yield = 0;
 }
 static void
-gvl_destroy(rb_global_vm_lock_t *gvl)
 {
 /*
 * only called once at VM shutdown (not atfork), another thread
@@ -405,21 +422,22 @@ gvl_destroy(rb_global_vm_lock_t *gvl)
 * the end of thread_start_func_2
 */
 if (0) {
- rb_native_cond_destroy(&gvl->switch_wait_cond);
- rb_native_cond_destroy(&gvl->switch_cond);
- rb_native_mutex_destroy(&gvl->lock);
 }
 clear_thread_cache_altstack();
 }
 #if defined(HAVE_WORKING_FORK)
 static void thread_cache_reset(void);
 static void
-gvl_atfork(rb_global_vm_lock_t *gvl)
 {
 thread_cache_reset();
- rb_gvl_init(gvl);
- gvl_acquire(gvl, GET_THREAD());
 }
 #endif
@@ -692,8 +710,8 @@ native_thread_init(rb_thread_t *th)
 #ifdef USE_UBF_LIST
 ccan_list_node_init(&nd->node.ubf);
 #endif
- rb_native_cond_initialize(&nd->cond.gvlq);
- if (&nd->cond.gvlq != &nd->cond.intr)
 rb_native_cond_initialize(&nd->cond.intr);
 }
@@ -706,8 +724,8 @@ native_thread_destroy(rb_thread_t *th)
 {
 native_thread_data_t *nd = &th->native_thread_data;
- rb_native_cond_destroy(&nd->cond.gvlq);
- if (&nd->cond.gvlq != &nd->cond.intr)
 rb_native_cond_destroy(&nd->cond.intr);
 /*
@@ -1155,6 +1173,8 @@ use_cached_thread(rb_thread_t *th)
 return 0;
 }
 static void
 clear_thread_cache_altstack(void)
 {
@@ -1170,6 +1190,7 @@ clear_thread_cache_altstack(void)
 rb_native_mutex_unlock(&thread_cache_lock);
 #endif
 }
 static int
 native_thread_create(rb_thread_t *th)
@@ -1270,7 +1291,7 @@ native_cond_sleep(rb_thread_t *th, rb_hrtime_t *rel)
 */
 const rb_hrtime_t max = (rb_hrtime_t)100000000 * RB_HRTIME_PER_SEC;
- GVL_UNLOCK_BEGIN(th);
 {
 rb_native_mutex_lock(lock);
 th->unblock.func = ubf_pthread_cond_signal;
@@ -1299,7 +1320,7 @@ native_cond_sleep(rb_thread_t *th, rb_hrtime_t *rel)
 rb_native_mutex_unlock(lock);
 }
- GVL_UNLOCK_END(th);
 thread_debug("native_sleep done\n");
 }
@@ -1362,7 +1383,7 @@ static void
 ubf_select(void *ptr)
 {
 rb_thread_t *th = (rb_thread_t *)ptr;
- rb_global_vm_lock_t *gvl = rb_ractor_gvl(th->ractor);
 const rb_thread_t *cur = ruby_thread_from_native(); /* may be 0 */
 register_ubf_list(th);
@@ -1377,17 +1398,17 @@ ubf_select(void *ptr)
 * sigwait_th thread, otherwise we can deadlock with a thread
 * in unblock_function_clear.
 */
- if (cur != gvl->timer && cur != sigwait_th) {
 /*
 * Double-checked locking above was to prevent nested locking
 * by the SAME thread. We use trylock here to prevent deadlocks
 * between DIFFERENT threads
 */
- if (rb_native_mutex_trylock(&gvl->lock) == 0) {
- if (!gvl->timer) {
 rb_thread_wakeup_timer_thread(-1);
 }
- rb_native_mutex_unlock(&gvl->lock);
 }
 }
@@ -2167,13 +2188,13 @@ ubf_ppoll_sleep(void *ignore)
 * Confirmed on FreeBSD 11.2 and Linux 4.19.
 * [ruby-core:90417] [Bug #15398]
 */
-#define GVL_UNLOCK_BEGIN_YIELD(th) do { \
 const native_thread_data_t *next; \
- rb_global_vm_lock_t *gvl = rb_ractor_gvl(th->ractor); \
 RB_GC_SAVE_MACHINE_CONTEXT(th); \
- rb_native_mutex_lock(&gvl->lock); \
- next = gvl_release_common(gvl); \
- rb_native_mutex_unlock(&gvl->lock); \
 if (!next && rb_ractor_living_thread_num(th->ractor) > 1) { \
 native_thread_yield(); \
 }
@@ -2195,28 +2216,29 @@ native_ppoll_sleep(rb_thread_t *th, rb_hrtime_t *rel)
 th->unblock.func = ubf_ppoll_sleep;
 rb_native_mutex_unlock(&th->interrupt_lock);
- GVL_UNLOCK_BEGIN_YIELD(th);
-
- if (!RUBY_VM_INTERRUPTED(th->ec)) {
- struct pollfd pfd[2];
- struct timespec ts;
-
- pfd[0].fd = signal_self_pipe.normal[0]; /* sigwait_fd */
- pfd[1].fd = signal_self_pipe.ub_main[0];
- pfd[0].events = pfd[1].events = POLLIN;
- if (ppoll(pfd, 2, rb_hrtime2timespec(&ts, rel), 0) > 0) {
- if (pfd[1].revents & POLLIN) {
- (void)consume_communication_pipe(pfd[1].fd);
 }
 }
- /*
- * do not read the sigwait_fd, here, let uplevel callers
- * or other threads that, otherwise we may steal and starve
- * other threads
- */
 }
- unblock_function_clear(th);
- GVL_UNLOCK_END(th);
 }
 static void
@@ -2230,16 +2252,18 @@ native_sleep(rb_thread_t *th, rb_hrtime_t *rel)
 th->unblock.func = ubf_sigwait;
 rb_native_mutex_unlock(&th->interrupt_lock);
- GVL_UNLOCK_BEGIN_YIELD(th);
-
- if (!RUBY_VM_INTERRUPTED(th->ec)) {
- rb_sigwait_sleep(th, sigwait_fd, rel);
- }
- else {
- check_signals_nogvl(th, sigwait_fd);
 }
- unblock_function_clear(th);
- GVL_UNLOCK_END(th);
 rb_sigwait_fd_put(th, sigwait_fd);
 rb_sigwait_fd_migrate(th->vm);
 }
author	Koichi Sasada <[email protected]>	2022-04-17 03:40:23 +0900
committer	Koichi Sasada <[email protected]>	2022-04-22 07:54:09 +0900
commit	1c4fc0241d125879e1e5169f267f26637772f3a7 ()
tree	d23704a9fc31fe8bfb29835ce0bdae3dc278b513 /thread_pthread.c
parent	cb02324c4e5c7aae0add0a5c4e5adbf637d9acb0 (diff)