ruby/thread_pthread_mn.c

1083 строки
32 KiB
C

// included by "thread_pthread.c"
#if USE_MN_THREADS
static void timer_thread_unregister_waiting(rb_thread_t *th, int fd, enum thread_sched_waiting_flag flags);
static bool
timer_thread_cancel_waiting(rb_thread_t *th)
{
bool canceled = false;
if (th->sched.waiting_reason.flags) {
rb_native_mutex_lock(&timer_th.waiting_lock);
{
if (th->sched.waiting_reason.flags) {
canceled = true;
ccan_list_del_init(&th->sched.waiting_reason.node);
if (th->sched.waiting_reason.flags & (thread_sched_waiting_io_read | thread_sched_waiting_io_write)) {
timer_thread_unregister_waiting(th, th->sched.waiting_reason.data.fd, th->sched.waiting_reason.flags);
}
th->sched.waiting_reason.flags = thread_sched_waiting_none;
}
}
rb_native_mutex_unlock(&timer_th.waiting_lock);
}
return canceled;
}
static void
ubf_event_waiting(void *ptr)
{
rb_thread_t *th = (rb_thread_t *)ptr;
struct rb_thread_sched *sched = TH_SCHED(th);
RUBY_DEBUG_LOG("th:%u", rb_th_serial(th));
VM_ASSERT(th->nt == NULL || !th_has_dedicated_nt(th));
// only once. it is safe because th->interrupt_lock is already acquired.
th->unblock.func = NULL;
th->unblock.arg = NULL;
bool canceled = timer_thread_cancel_waiting(th);
thread_sched_lock(sched, th);
{
if (sched->running == th) {
RUBY_DEBUG_LOG("not waiting yet");
}
else if (canceled) {
thread_sched_to_ready_common(sched, th, true, false);
}
else {
RUBY_DEBUG_LOG("already not waiting");
}
}
thread_sched_unlock(sched, th);
}
static bool timer_thread_register_waiting(rb_thread_t *th, int fd, enum thread_sched_waiting_flag flags, rb_hrtime_t *rel);
// return true if timed out
static bool
thread_sched_wait_events(struct rb_thread_sched *sched, rb_thread_t *th, int fd, enum thread_sched_waiting_flag events, rb_hrtime_t *rel)
{
VM_ASSERT(!th_has_dedicated_nt(th)); // on SNT
volatile bool timedout = false, need_cancel = false;
if (timer_thread_register_waiting(th, fd, events, rel)) {
RUBY_DEBUG_LOG("wait fd:%d", fd);
RB_VM_SAVE_MACHINE_CONTEXT(th);
setup_ubf(th, ubf_event_waiting, (void *)th);
RB_INTERNAL_THREAD_HOOK(RUBY_INTERNAL_THREAD_EVENT_SUSPENDED, th);
thread_sched_lock(sched, th);
{
if (th->sched.waiting_reason.flags == thread_sched_waiting_none) {
// already awaken
}
else if (RUBY_VM_INTERRUPTED(th->ec)) {
need_cancel = true;
}
else {
RUBY_DEBUG_LOG("sleep");
th->status = THREAD_STOPPED_FOREVER;
thread_sched_wakeup_next_thread(sched, th, true);
thread_sched_wait_running_turn(sched, th, true);
RUBY_DEBUG_LOG("wakeup");
}
timedout = th->sched.waiting_reason.data.result == 0;
}
thread_sched_unlock(sched, th);
if (need_cancel) {
timer_thread_cancel_waiting(th);
}
setup_ubf(th, NULL, NULL); // TODO: maybe it is already NULL?
th->status = THREAD_RUNNABLE;
}
else {
RUBY_DEBUG_LOG("can not wait fd:%d", fd);
return false;
}
VM_ASSERT(sched->running == th);
return timedout;
}
/// stack management
static int
get_sysconf_page_size(void)
{
static long page_size = 0;
if (UNLIKELY(page_size == 0)) {
page_size = sysconf(_SC_PAGESIZE);
VM_ASSERT(page_size < INT_MAX);
}
return (int)page_size;
}
#define MSTACK_CHUNK_SIZE (512 * 1024 * 1024) // 512MB
#define MSTACK_PAGE_SIZE get_sysconf_page_size()
#define MSTACK_CHUNK_PAGE_NUM (MSTACK_CHUNK_SIZE / MSTACK_PAGE_SIZE - 1) // 1 is start redzone
// 512MB chunk
// 131,072 pages (> 65,536)
// 0th page is Redzone. Start from 1st page.
/*
* <--> machine stack + vm stack
* ----------------------------------
* |HD...|RZ| ... |RZ| ... ... |RZ|
* <------------- 512MB ------------->
*/
static struct nt_stack_chunk_header {
struct nt_stack_chunk_header *prev_chunk;
struct nt_stack_chunk_header *prev_free_chunk;
uint16_t start_page;
uint16_t stack_count;
uint16_t uninitialized_stack_count;
uint16_t free_stack_pos;
uint16_t free_stack[];
} *nt_stack_chunks = NULL,
*nt_free_stack_chunks = NULL;
struct nt_machine_stack_footer {
struct nt_stack_chunk_header *ch;
size_t index;
};
static rb_nativethread_lock_t nt_machine_stack_lock = RB_NATIVETHREAD_LOCK_INIT;
#include <sys/mman.h>
// vm_stack_size + machine_stack_size + 1 * (guard page size)
static inline size_t
nt_thread_stack_size(void)
{
static size_t msz;
if (LIKELY(msz > 0)) return msz;
rb_vm_t *vm = GET_VM();
int sz = (int)(vm->default_params.thread_vm_stack_size + vm->default_params.thread_machine_stack_size + MSTACK_PAGE_SIZE);
int page_num = roomof(sz, MSTACK_PAGE_SIZE);
msz = (size_t)page_num * MSTACK_PAGE_SIZE;
return msz;
}
static struct nt_stack_chunk_header *
nt_alloc_thread_stack_chunk(void)
{
int mmap_flags = MAP_ANONYMOUS | MAP_PRIVATE;
#if defined(MAP_STACK) && !defined(__FreeBSD__) && !defined(__FreeBSD_kernel__)
mmap_flags |= MAP_STACK;
#endif
const char *m = (void *)mmap(NULL, MSTACK_CHUNK_SIZE, PROT_READ | PROT_WRITE, mmap_flags, -1, 0);
if (m == MAP_FAILED) {
return NULL;
}
size_t msz = nt_thread_stack_size();
int header_page_cnt = 1;
int stack_count = ((MSTACK_CHUNK_PAGE_NUM - header_page_cnt) * MSTACK_PAGE_SIZE) / msz;
int ch_size = sizeof(struct nt_stack_chunk_header) + sizeof(uint16_t) * stack_count;
if (ch_size > MSTACK_PAGE_SIZE * header_page_cnt) {
header_page_cnt = (ch_size + MSTACK_PAGE_SIZE - 1) / MSTACK_PAGE_SIZE;
stack_count = ((MSTACK_CHUNK_PAGE_NUM - header_page_cnt) * MSTACK_PAGE_SIZE) / msz;
}
VM_ASSERT(stack_count <= UINT16_MAX);
struct nt_stack_chunk_header *ch = (struct nt_stack_chunk_header *)m;
ch->start_page = header_page_cnt;
ch->prev_chunk = nt_stack_chunks;
ch->prev_free_chunk = nt_free_stack_chunks;
ch->uninitialized_stack_count = ch->stack_count = (uint16_t)stack_count;
ch->free_stack_pos = 0;
RUBY_DEBUG_LOG("ch:%p start_page:%d stack_cnt:%d stack_size:%d", ch, (int)ch->start_page, (int)ch->stack_count, (int)msz);
return ch;
}
static void *
nt_stack_chunk_get_stack_start(struct nt_stack_chunk_header *ch, size_t idx)
{
const char *m = (char *)ch;
return (void *)(m + ch->start_page * MSTACK_PAGE_SIZE + idx * nt_thread_stack_size());
}
static struct nt_machine_stack_footer *
nt_stack_chunk_get_msf(const rb_vm_t *vm, const char *mstack)
{
// TODO: stack direction
const size_t msz = vm->default_params.thread_machine_stack_size;
return (struct nt_machine_stack_footer *)&mstack[msz - sizeof(struct nt_machine_stack_footer)];
}
static void *
nt_stack_chunk_get_stack(const rb_vm_t *vm, struct nt_stack_chunk_header *ch, size_t idx, void **vm_stack, void **machine_stack)
{
// TODO: only support stack going down
// [VM ... <GUARD> machine stack ...]
const char *vstack, *mstack;
const char *guard_page;
vstack = nt_stack_chunk_get_stack_start(ch, idx);
guard_page = vstack + vm->default_params.thread_vm_stack_size;
mstack = guard_page + MSTACK_PAGE_SIZE;
struct nt_machine_stack_footer *msf = nt_stack_chunk_get_msf(vm, mstack);
msf->ch = ch;
msf->index = idx;
#if 0
RUBY_DEBUG_LOG("msf:%p vstack:%p-%p guard_page:%p-%p mstack:%p-%p", msf,
vstack, (void *)(guard_page-1),
guard_page, (void *)(mstack-1),
mstack, (void *)(msf));
#endif
*vm_stack = (void *)vstack;
*machine_stack = (void *)mstack;
return (void *)guard_page;
}
RBIMPL_ATTR_MAYBE_UNUSED()
static void
nt_stack_chunk_dump(void)
{
struct nt_stack_chunk_header *ch;
int i;
fprintf(stderr, "** nt_stack_chunks\n");
ch = nt_stack_chunks;
for (i=0; ch; i++, ch = ch->prev_chunk) {
fprintf(stderr, "%d %p free_pos:%d\n", i, (void *)ch, (int)ch->free_stack_pos);
}
fprintf(stderr, "** nt_free_stack_chunks\n");
ch = nt_free_stack_chunks;
for (i=0; ch; i++, ch = ch->prev_free_chunk) {
fprintf(stderr, "%d %p free_pos:%d\n", i, (void *)ch, (int)ch->free_stack_pos);
}
}
static int
nt_guard_page(const char *p, size_t len)
{
if (mprotect((void *)p, len, PROT_NONE) != -1) {
return 0;
}
else {
return errno;
}
}
static int
nt_alloc_stack(rb_vm_t *vm, void **vm_stack, void **machine_stack)
{
int err = 0;
rb_native_mutex_lock(&nt_machine_stack_lock);
{
retry:
if (nt_free_stack_chunks) {
struct nt_stack_chunk_header *ch = nt_free_stack_chunks;
if (ch->free_stack_pos > 0) {
RUBY_DEBUG_LOG("free_stack_pos:%d", ch->free_stack_pos);
nt_stack_chunk_get_stack(vm, ch, ch->free_stack[--ch->free_stack_pos], vm_stack, machine_stack);
}
else if (ch->uninitialized_stack_count > 0) {
RUBY_DEBUG_LOG("uninitialized_stack_count:%d", ch->uninitialized_stack_count);
size_t idx = ch->stack_count - ch->uninitialized_stack_count--;
void *guard_page = nt_stack_chunk_get_stack(vm, ch, idx, vm_stack, machine_stack);
err = nt_guard_page(guard_page, MSTACK_PAGE_SIZE);
}
else {
nt_free_stack_chunks = ch->prev_free_chunk;
ch->prev_free_chunk = NULL;
goto retry;
}
}
else {
struct nt_stack_chunk_header *p = nt_alloc_thread_stack_chunk();
if (p == NULL) {
err = errno;
}
else {
nt_free_stack_chunks = nt_stack_chunks = p;
goto retry;
}
}
}
rb_native_mutex_unlock(&nt_machine_stack_lock);
return err;
}
static void
nt_madvise_free_or_dontneed(void *addr, size_t len)
{
/* There is no real way to perform error handling here. Both MADV_FREE
* and MADV_DONTNEED are both documented to pretty much only return EINVAL
* for a huge variety of errors. It's indistinguishable if madvise fails
* because the parameters were bad, or because the kernel we're running on
* does not support the given advice. This kind of free-but-don't-unmap
* is best-effort anyway, so don't sweat it.
*
* n.b. A very common case of "the kernel doesn't support MADV_FREE and
* returns EINVAL" is running under the `rr` debugger; it makes all
* MADV_FREE calls return EINVAL. */
#if defined(MADV_FREE)
int r = madvise(addr, len, MADV_FREE);
// Return on success, or else try MADV_DONTNEED
if (r == 0) return;
#endif
#if defined(MADV_DONTNEED)
madvise(addr, len, MADV_DONTNEED);
#endif
}
static void
nt_free_stack(void *mstack)
{
if (!mstack) return;
rb_native_mutex_lock(&nt_machine_stack_lock);
{
struct nt_machine_stack_footer *msf = nt_stack_chunk_get_msf(GET_VM(), mstack);
struct nt_stack_chunk_header *ch = msf->ch;
int idx = (int)msf->index;
void *stack = nt_stack_chunk_get_stack_start(ch, idx);
RUBY_DEBUG_LOG("stack:%p mstack:%p ch:%p index:%d", stack, mstack, ch, idx);
if (ch->prev_free_chunk == NULL) {
ch->prev_free_chunk = nt_free_stack_chunks;
nt_free_stack_chunks = ch;
}
ch->free_stack[ch->free_stack_pos++] = idx;
// clear the stack pages
nt_madvise_free_or_dontneed(stack, nt_thread_stack_size());
}
rb_native_mutex_unlock(&nt_machine_stack_lock);
}
static int
native_thread_check_and_create_shared(rb_vm_t *vm)
{
bool need_to_make = false;
rb_native_mutex_lock(&vm->ractor.sched.lock);
{
unsigned int snt_cnt = vm->ractor.sched.snt_cnt;
if (!vm->ractor.main_ractor->threads.sched.enable_mn_threads) snt_cnt++; // do not need snt for main ractor
if (((int)snt_cnt < MINIMUM_SNT) ||
(snt_cnt < vm->ractor.cnt &&
snt_cnt < vm->ractor.sched.max_cpu)) {
RUBY_DEBUG_LOG("added snt:%u dnt:%u ractor_cnt:%u grq_cnt:%u",
vm->ractor.sched.snt_cnt,
vm->ractor.sched.dnt_cnt,
vm->ractor.cnt,
vm->ractor.sched.grq_cnt);
vm->ractor.sched.snt_cnt++;
need_to_make = true;
}
else {
RUBY_DEBUG_LOG("snt:%d ractor_cnt:%d", (int)vm->ractor.sched.snt_cnt, (int)vm->ractor.cnt);
}
}
rb_native_mutex_unlock(&vm->ractor.sched.lock);
if (need_to_make) {
struct rb_native_thread *nt = native_thread_alloc();
nt->vm = vm;
return native_thread_create0(nt);
}
else {
return 0;
}
}
static COROUTINE
co_start(struct coroutine_context *from, struct coroutine_context *self)
{
#ifdef RUBY_ASAN_ENABLED
__sanitizer_finish_switch_fiber(self->fake_stack,
(const void**)&from->stack_base, &from->stack_size);
#endif
rb_thread_t *th = (rb_thread_t *)self->argument;
struct rb_thread_sched *sched = TH_SCHED(th);
VM_ASSERT(th->nt != NULL);
VM_ASSERT(th == sched->running);
VM_ASSERT(sched->lock_owner == NULL);
// RUBY_DEBUG_LOG("th:%u", rb_th_serial(th));
thread_sched_set_lock_owner(sched, th);
thread_sched_add_running_thread(TH_SCHED(th), th);
thread_sched_unlock(sched, th);
{
RB_INTERNAL_THREAD_HOOK(RUBY_INTERNAL_THREAD_EVENT_RESUMED, th);
call_thread_start_func_2(th);
}
thread_sched_lock(sched, NULL);
RUBY_DEBUG_LOG("terminated th:%d", (int)th->serial);
// Thread is terminated
struct rb_native_thread *nt = th->nt;
bool is_dnt = th_has_dedicated_nt(th);
native_thread_assign(NULL, th);
rb_ractor_set_current_ec(th->ractor, NULL);
if (is_dnt) {
// SNT became DNT while running. Just return to the nt_context
th->sched.finished = true;
coroutine_transfer0(self, nt->nt_context, true);
}
else {
rb_vm_t *vm = th->vm;
bool has_ready_ractor = vm->ractor.sched.grq_cnt > 0; // at least this ractor is not queued
rb_thread_t *next_th = sched->running;
if (!has_ready_ractor && next_th && !next_th->nt) {
// switch to the next thread
thread_sched_set_lock_owner(sched, NULL);
thread_sched_switch0(th->sched.context, next_th, nt, true);
th->sched.finished = true;
}
else {
// switch to the next Ractor
th->sched.finished = true;
coroutine_transfer0(self, nt->nt_context, true);
}
}
rb_bug("unreachable");
}
static int
native_thread_create_shared(rb_thread_t *th)
{
// setup coroutine
rb_vm_t *vm = th->vm;
void *vm_stack = NULL, *machine_stack = NULL;
int err = nt_alloc_stack(vm, &vm_stack, &machine_stack);
if (err) return err;
VM_ASSERT(vm_stack < machine_stack);
// setup vm stack
size_t vm_stack_words = th->vm->default_params.thread_vm_stack_size/sizeof(VALUE);
rb_ec_initialize_vm_stack(th->ec, vm_stack, vm_stack_words);
// setup machine stack
size_t machine_stack_size = vm->default_params.thread_machine_stack_size - sizeof(struct nt_machine_stack_footer);
th->ec->machine.stack_start = (void *)((uintptr_t)machine_stack + machine_stack_size);
th->ec->machine.stack_maxsize = machine_stack_size; // TODO
th->sched.context_stack = machine_stack;
th->sched.context = ruby_xmalloc(sizeof(struct coroutine_context));
coroutine_initialize(th->sched.context, co_start, machine_stack, machine_stack_size);
th->sched.context->argument = th;
RUBY_DEBUG_LOG("th:%u vm_stack:%p machine_stack:%p", rb_th_serial(th), vm_stack, machine_stack);
thread_sched_to_ready(TH_SCHED(th), th);
// setup nt
return native_thread_check_and_create_shared(th->vm);
}
#else // USE_MN_THREADS
static int
native_thread_create_shared(rb_thread_t *th)
{
rb_bug("unreachable");
}
static bool
thread_sched_wait_events(struct rb_thread_sched *sched, rb_thread_t *th, int fd, enum thread_sched_waiting_flag events, rb_hrtime_t *rel)
{
rb_bug("unreachable");
}
#endif // USE_MN_THREADS
/// EPOLL/KQUEUE specific code
#if (HAVE_SYS_EPOLL_H || HAVE_SYS_EVENT_H) && USE_MN_THREADS
static bool
fd_readable_nonblock(int fd)
{
struct pollfd pfd = {
.fd = fd,
.events = POLLIN,
};
return poll(&pfd, 1, 0) != 0;
}
static bool
fd_writable_nonblock(int fd)
{
struct pollfd pfd = {
.fd = fd,
.events = POLLOUT,
};
return poll(&pfd, 1, 0) != 0;
}
static void
verify_waiting_list(void)
{
#if VM_CHECK_MODE > 0
struct rb_thread_sched_waiting *w, *prev_w = NULL;
// waiting list's timeout order should be [1, 2, 3, ..., 0, 0, 0]
ccan_list_for_each(&timer_th.waiting, w, node) {
// fprintf(stderr, "verify_waiting_list th:%u abs:%lu\n", rb_th_serial(wth), (unsigned long)wth->sched.waiting_reason.data.timeout);
if (prev_w) {
rb_hrtime_t timeout = w->data.timeout;
rb_hrtime_t prev_timeout = w->data.timeout;
VM_ASSERT(timeout == 0 || prev_timeout <= timeout);
}
prev_w = w;
}
#endif
}
#if HAVE_SYS_EVENT_H // kqueue helpers
static enum thread_sched_waiting_flag
kqueue_translate_filter_to_flags(int16_t filter)
{
switch (filter) {
case EVFILT_READ:
return thread_sched_waiting_io_read;
case EVFILT_WRITE:
return thread_sched_waiting_io_write;
case EVFILT_TIMER:
return thread_sched_waiting_timeout;
default:
rb_bug("kevent filter:%d not supported", filter);
}
}
static int
kqueue_wait(rb_vm_t *vm)
{
struct timespec calculated_timeout;
struct timespec *timeout = NULL;
int timeout_ms = timer_thread_set_timeout(vm);
if (timeout_ms >= 0) {
calculated_timeout.tv_sec = timeout_ms / 1000;
calculated_timeout.tv_nsec = (timeout_ms % 1000) * 1000000;
timeout = &calculated_timeout;
}
return kevent(timer_th.event_fd, NULL, 0, timer_th.finished_events, KQUEUE_EVENTS_MAX, timeout);
}
static void
kqueue_create(void)
{
if ((timer_th.event_fd = kqueue()) == -1) rb_bug("kqueue creation failed (errno:%d)", errno);
int flags = fcntl(timer_th.event_fd, F_GETFD);
if (flags == -1) {
rb_bug("kqueue GETFD failed (errno:%d)", errno);
}
flags |= FD_CLOEXEC;
if (fcntl(timer_th.event_fd, F_SETFD, flags) == -1) {
rb_bug("kqueue SETFD failed (errno:%d)", errno);
}
}
static void
kqueue_unregister_waiting(int fd, enum thread_sched_waiting_flag flags)
{
if (flags) {
struct kevent ke[2];
int num_events = 0;
if (flags & thread_sched_waiting_io_read) {
EV_SET(&ke[num_events], fd, EVFILT_READ, EV_DELETE, 0, 0, NULL);
num_events++;
}
if (flags & thread_sched_waiting_io_write) {
EV_SET(&ke[num_events], fd, EVFILT_WRITE, EV_DELETE, 0, 0, NULL);
num_events++;
}
if (kevent(timer_th.event_fd, ke, num_events, NULL, 0, NULL) == -1) {
perror("kevent");
rb_bug("unregister/kevent fails. errno:%d", errno);
}
}
}
static bool
kqueue_already_registered(int fd)
{
struct rb_thread_sched_waiting *w, *found_w = NULL;
ccan_list_for_each(&timer_th.waiting, w, node) {
// Similar to EEXIST in epoll_ctl, but more strict because it checks fd rather than flags
// for simplicity
if (w->flags && w->data.fd == fd) {
found_w = w;
break;
}
}
return found_w != NULL;
}
#endif // HAVE_SYS_EVENT_H
// return false if the fd is not waitable or not need to wait.
static bool
timer_thread_register_waiting(rb_thread_t *th, int fd, enum thread_sched_waiting_flag flags, rb_hrtime_t *rel)
{
RUBY_DEBUG_LOG("th:%u fd:%d flag:%d rel:%lu", rb_th_serial(th), fd, flags, rel ? (unsigned long)*rel : 0);
VM_ASSERT(th == NULL || TH_SCHED(th)->running == th);
VM_ASSERT(flags != 0);
rb_hrtime_t abs = 0; // 0 means no timeout
if (rel) {
if (*rel > 0) {
flags |= thread_sched_waiting_timeout;
}
else {
return false;
}
}
if (rel && *rel > 0) {
flags |= thread_sched_waiting_timeout;
}
#if HAVE_SYS_EVENT_H
struct kevent ke[2];
int num_events = 0;
#else
uint32_t epoll_events = 0;
#endif
if (flags & thread_sched_waiting_timeout) {
VM_ASSERT(rel != NULL);
abs = rb_hrtime_add(rb_hrtime_now(), *rel);
}
if (flags & thread_sched_waiting_io_read) {
if (!(flags & thread_sched_waiting_io_force) && fd_readable_nonblock(fd)) {
RUBY_DEBUG_LOG("fd_readable_nonblock");
return false;
}
else {
VM_ASSERT(fd >= 0);
#if HAVE_SYS_EVENT_H
EV_SET(&ke[num_events], fd, EVFILT_READ, EV_ADD, 0, 0, (void *)th);
num_events++;
#else
epoll_events |= EPOLLIN;
#endif
}
}
if (flags & thread_sched_waiting_io_write) {
if (!(flags & thread_sched_waiting_io_force) && fd_writable_nonblock(fd)) {
RUBY_DEBUG_LOG("fd_writable_nonblock");
return false;
}
else {
VM_ASSERT(fd >= 0);
#if HAVE_SYS_EVENT_H
EV_SET(&ke[num_events], fd, EVFILT_WRITE, EV_ADD, 0, 0, (void *)th);
num_events++;
#else
epoll_events |= EPOLLOUT;
#endif
}
}
rb_native_mutex_lock(&timer_th.waiting_lock);
{
#if HAVE_SYS_EVENT_H
if (num_events > 0) {
if (kqueue_already_registered(fd)) {
rb_native_mutex_unlock(&timer_th.waiting_lock);
return false;
}
if (kevent(timer_th.event_fd, ke, num_events, NULL, 0, NULL) == -1) {
RUBY_DEBUG_LOG("failed (%d)", errno);
switch (errno) {
case EBADF:
// the fd is closed?
case EINTR:
// signal received? is there a sensible way to handle this?
default:
perror("kevent");
rb_bug("register/kevent failed(fd:%d, errno:%d)", fd, errno);
}
}
RUBY_DEBUG_LOG("kevent(add, fd:%d) success", fd);
}
#else
if (epoll_events) {
struct epoll_event event = {
.events = epoll_events,
.data = {
.ptr = (void *)th,
},
};
if (epoll_ctl(timer_th.event_fd, EPOLL_CTL_ADD, fd, &event) == -1) {
RUBY_DEBUG_LOG("failed (%d)", errno);
switch (errno) {
case EBADF:
// the fd is closed?
case EPERM:
// the fd doesn't support epoll
case EEXIST:
// the fd is already registered by another thread
rb_native_mutex_unlock(&timer_th.waiting_lock);
return false;
default:
perror("epoll_ctl");
rb_bug("register/epoll_ctl failed(fd:%d, errno:%d)", fd, errno);
}
}
RUBY_DEBUG_LOG("epoll_ctl(add, fd:%d, events:%d) success", fd, epoll_events);
}
#endif
if (th) {
VM_ASSERT(th->sched.waiting_reason.flags == thread_sched_waiting_none);
// setup waiting information
{
th->sched.waiting_reason.flags = flags;
th->sched.waiting_reason.data.timeout = abs;
th->sched.waiting_reason.data.fd = fd;
th->sched.waiting_reason.data.result = 0;
}
if (abs == 0) { // no timeout
VM_ASSERT(!(flags & thread_sched_waiting_timeout));
ccan_list_add_tail(&timer_th.waiting, &th->sched.waiting_reason.node);
}
else {
RUBY_DEBUG_LOG("abs:%lu", (unsigned long)abs);
VM_ASSERT(flags & thread_sched_waiting_timeout);
// insert th to sorted list (TODO: O(n))
struct rb_thread_sched_waiting *w, *prev_w = NULL;
ccan_list_for_each(&timer_th.waiting, w, node) {
if ((w->flags & thread_sched_waiting_timeout) &&
w->data.timeout < abs) {
prev_w = w;
}
else {
break;
}
}
if (prev_w) {
ccan_list_add_after(&timer_th.waiting, &prev_w->node, &th->sched.waiting_reason.node);
}
else {
ccan_list_add(&timer_th.waiting, &th->sched.waiting_reason.node);
}
verify_waiting_list();
// update timeout seconds
timer_thread_wakeup();
}
}
else {
VM_ASSERT(abs == 0);
}
}
rb_native_mutex_unlock(&timer_th.waiting_lock);
return true;
}
static void
timer_thread_unregister_waiting(rb_thread_t *th, int fd, enum thread_sched_waiting_flag flags)
{
RUBY_DEBUG_LOG("th:%u fd:%d", rb_th_serial(th), fd);
#if HAVE_SYS_EVENT_H
kqueue_unregister_waiting(fd, flags);
#else
// Linux 2.6.9 or later is needed to pass NULL as data.
if (epoll_ctl(timer_th.event_fd, EPOLL_CTL_DEL, fd, NULL) == -1) {
switch (errno) {
case EBADF:
// just ignore. maybe fd is closed.
break;
default:
perror("epoll_ctl");
rb_bug("unregister/epoll_ctl fails. errno:%d", errno);
}
}
#endif
}
static void
timer_thread_setup_mn(void)
{
#if HAVE_SYS_EVENT_H
kqueue_create();
RUBY_DEBUG_LOG("kqueue_fd:%d", timer_th.event_fd);
#else
if ((timer_th.event_fd = epoll_create1(EPOLL_CLOEXEC)) == -1) rb_bug("epoll_create (errno:%d)", errno);
RUBY_DEBUG_LOG("epoll_fd:%d", timer_th.event_fd);
#endif
RUBY_DEBUG_LOG("comm_fds:%d/%d", timer_th.comm_fds[0], timer_th.comm_fds[1]);
timer_thread_register_waiting(NULL, timer_th.comm_fds[0], thread_sched_waiting_io_read | thread_sched_waiting_io_force, NULL);
}
static int
event_wait(rb_vm_t *vm)
{
#if HAVE_SYS_EVENT_H
int r = kqueue_wait(vm);
#else
int r = epoll_wait(timer_th.event_fd, timer_th.finished_events, EPOLL_EVENTS_MAX, timer_thread_set_timeout(vm));
#endif
return r;
}
/*
* The purpose of the timer thread:
*
* (1) Periodic checking
* (1-1) Provide time slice for active NTs
* (1-2) Check NT shortage
* (1-3) Periodic UBF (global)
* (1-4) Lazy GRQ deq start
* (2) Receive notification
* (2-1) async I/O termination
* (2-2) timeout
* (2-2-1) sleep(n)
* (2-2-2) timeout(n), I/O, ...
*/
static void
timer_thread_polling(rb_vm_t *vm)
{
int r = event_wait(vm);
RUBY_DEBUG_LOG("r:%d errno:%d", r, errno);
switch (r) {
case 0: // timeout
RUBY_DEBUG_LOG("timeout%s", "");
ractor_sched_lock(vm, NULL);
{
// (1-1) timeslice
timer_thread_check_timeslice(vm);
// (1-4) lazy grq deq
if (vm->ractor.sched.grq_cnt > 0) {
RUBY_DEBUG_LOG("GRQ cnt: %u", vm->ractor.sched.grq_cnt);
rb_native_cond_signal(&vm->ractor.sched.cond);
}
}
ractor_sched_unlock(vm, NULL);
// (1-2)
native_thread_check_and_create_shared(vm);
break;
case -1:
switch (errno) {
case EINTR:
// simply retry
break;
default:
perror("event_wait");
rb_bug("event_wait errno:%d", errno);
}
break;
default:
RUBY_DEBUG_LOG("%d event(s)", r);
#if HAVE_SYS_EVENT_H
for (int i=0; i<r; i++) {
rb_thread_t *th = (rb_thread_t *)timer_th.finished_events[i].udata;
int fd = (int)timer_th.finished_events[i].ident;
int16_t filter = timer_th.finished_events[i].filter;
if (th == NULL) {
// wakeup timerthread
RUBY_DEBUG_LOG("comm from fd:%d", timer_th.comm_fds[1]);
consume_communication_pipe(timer_th.comm_fds[0]);
}
else {
// wakeup specific thread by IO
RUBY_DEBUG_LOG("io event. wakeup_th:%u event:%s%s",
rb_th_serial(th),
(filter == EVFILT_READ) ? "read/" : "",
(filter == EVFILT_WRITE) ? "write/" : "");
rb_native_mutex_lock(&timer_th.waiting_lock);
{
if (th->sched.waiting_reason.flags) {
// delete from chain
ccan_list_del_init(&th->sched.waiting_reason.node);
timer_thread_unregister_waiting(th, fd, kqueue_translate_filter_to_flags(filter));
th->sched.waiting_reason.flags = thread_sched_waiting_none;
th->sched.waiting_reason.data.fd = -1;
th->sched.waiting_reason.data.result = filter;
timer_thread_wakeup_thread(th);
}
else {
// already released
}
}
rb_native_mutex_unlock(&timer_th.waiting_lock);
}
}
#else
for (int i=0; i<r; i++) {
rb_thread_t *th = (rb_thread_t *)timer_th.finished_events[i].data.ptr;
if (th == NULL) {
// wakeup timerthread
RUBY_DEBUG_LOG("comm from fd:%d", timer_th.comm_fds[1]);
consume_communication_pipe(timer_th.comm_fds[0]);
}
else {
// wakeup specific thread by IO
uint32_t events = timer_th.finished_events[i].events;
RUBY_DEBUG_LOG("io event. wakeup_th:%u event:%s%s%s%s%s%s",
rb_th_serial(th),
(events & EPOLLIN) ? "in/" : "",
(events & EPOLLOUT) ? "out/" : "",
(events & EPOLLRDHUP) ? "RDHUP/" : "",
(events & EPOLLPRI) ? "pri/" : "",
(events & EPOLLERR) ? "err/" : "",
(events & EPOLLHUP) ? "hup/" : "");
rb_native_mutex_lock(&timer_th.waiting_lock);
{
if (th->sched.waiting_reason.flags) {
// delete from chain
ccan_list_del_init(&th->sched.waiting_reason.node);
timer_thread_unregister_waiting(th, th->sched.waiting_reason.data.fd, th->sched.waiting_reason.flags);
th->sched.waiting_reason.flags = thread_sched_waiting_none;
th->sched.waiting_reason.data.fd = -1;
th->sched.waiting_reason.data.result = (int)events;
timer_thread_wakeup_thread(th);
}
else {
// already released
}
}
rb_native_mutex_unlock(&timer_th.waiting_lock);
}
}
#endif
}
}
#else // HAVE_SYS_EPOLL_H || HAVE_SYS_EVENT_H
static void
timer_thread_setup_mn(void)
{
// do nothing
}
static void
timer_thread_polling(rb_vm_t *vm)
{
int timeout = timer_thread_set_timeout(vm);
struct pollfd pfd = {
.fd = timer_th.comm_fds[0],
.events = POLLIN,
};
int r = poll(&pfd, 1, timeout);
switch (r) {
case 0: // timeout
rb_native_mutex_lock(&vm->ractor.sched.lock);
{
// (1-1) timeslice
timer_thread_check_timeslice(vm);
}
rb_native_mutex_unlock(&vm->ractor.sched.lock);
break;
case -1: // error
switch (errno) {
case EINTR:
// simply retry
break;
default:
perror("poll");
rb_bug("poll errno:%d", errno);
break;
}
case 1:
consume_communication_pipe(timer_th.comm_fds[0]);
break;
default:
rb_bug("unreachbale");
}
}
#endif // HAVE_SYS_EPOLL_H || HAVE_SYS_EVENT_H