ruby/vm_sync.h
Koichi Sasada ef2bb61018 Ractor::Port
* Added `Ractor::Port`
  * `Ractor::Port#receive` (support multi-threads)
  * `Rcator::Port#close`
  * `Ractor::Port#closed?`
* Added some methods
  * `Ractor#join`
  * `Ractor#value`
  * `Ractor#monitor`
  * `Ractor#unmonitor`
* Removed some methods
  * `Ractor#take`
  * `Ractor.yield`
* Change the spec
  * `Racotr.select`

You can wait for multiple sequences of messages with `Ractor::Port`.

```ruby
ports = 3.times.map{ Ractor::Port.new }
ports.map.with_index do |port, ri|
  Ractor.new port,ri do |port, ri|
    3.times{|i| port << "r#{ri}-#{i}"}
  end
end

p ports.each{|port| pp 3.times.map{port.receive}}

```

In this example, we use 3 ports, and 3 Ractors send messages to them respectively.
We can receive a series of messages from each port.

You can use `Ractor#value` to get the last value of a Ractor's block:

```ruby
result = Ractor.new do
  heavy_task()
end.value
```

You can wait for the termination of a Ractor with `Ractor#join` like this:

```ruby
Ractor.new do
  some_task()
end.join
```

`#value` and `#join` are similar to `Thread#value` and `Thread#join`.

To implement `#join`, `Ractor#monitor` (and `Ractor#unmonitor`) is introduced.

This commit changes `Ractor.select()` method.
It now only accepts ports or Ractors, and returns when a port receives a message or a Ractor terminates.

We removes `Ractor.yield` and `Ractor#take` because:
* `Ractor::Port` supports most of similar use cases in a simpler manner.
* Removing them significantly simplifies the code.

We also change the internal thread scheduler code (thread_pthread.c):
* During barrier synchronization, we keep the `ractor_sched` lock to avoid deadlocks.
  This lock is released by `rb_ractor_sched_barrier_end()`
  which is called at the end of operations that require the barrier.
* fix potential deadlock issues by checking interrupts just before setting UBF.

https://bugs.ruby-lang.org/issues/21262
2025-05-31 04:01:33 +09:00

154 lines
4.6 KiB
C

#ifndef RUBY_VM_SYNC_H
#define RUBY_VM_SYNC_H
#include "vm_debug.h"
#include "debug_counter.h"
#if USE_RUBY_DEBUG_LOG
#define LOCATION_ARGS const char *file, int line
#define LOCATION_PARAMS file, line
#define APPEND_LOCATION_ARGS , const char *file, int line
#define APPEND_LOCATION_PARAMS , file, line
#else
#define LOCATION_ARGS void
#define LOCATION_PARAMS
#define APPEND_LOCATION_ARGS
#define APPEND_LOCATION_PARAMS
#endif
bool rb_vm_locked_p(void);
void rb_vm_lock_body(LOCATION_ARGS);
void rb_vm_unlock_body(LOCATION_ARGS);
struct rb_ractor_struct;
NOINLINE(void rb_vm_lock_enter_body_cr(struct rb_ractor_struct *cr, unsigned int *lev APPEND_LOCATION_ARGS));
NOINLINE(void rb_vm_lock_enter_body_nb(unsigned int *lev APPEND_LOCATION_ARGS));
NOINLINE(void rb_vm_lock_enter_body(unsigned int *lev APPEND_LOCATION_ARGS));
void rb_vm_lock_leave_body_nb(unsigned int *lev APPEND_LOCATION_ARGS);
void rb_vm_lock_leave_body(unsigned int *lev APPEND_LOCATION_ARGS);
void rb_vm_barrier(void);
#if RUBY_DEBUG
// GET_VM()
#include "vm_core.h"
#endif
RUBY_EXTERN struct rb_ractor_struct *ruby_single_main_ractor; // ractor.c
static inline bool
rb_multi_ractor_p(void)
{
if (LIKELY(ruby_single_main_ractor)) {
// 0 on boot time.
RUBY_ASSERT(GET_VM()->ractor.cnt <= 1);
return false;
}
else {
// multi-ractor mode can run ractor.cnt == 1
return true;
}
}
static inline void
rb_vm_lock(const char *file, int line)
{
RB_DEBUG_COUNTER_INC(vm_sync_lock);
if (rb_multi_ractor_p()) {
rb_vm_lock_body(LOCATION_PARAMS);
}
}
static inline void
rb_vm_unlock(const char *file, int line)
{
if (rb_multi_ractor_p()) {
rb_vm_unlock_body(LOCATION_PARAMS);
}
}
static inline void
rb_vm_lock_enter(unsigned int *lev, const char *file, int line)
{
RB_DEBUG_COUNTER_INC(vm_sync_lock_enter);
if (rb_multi_ractor_p()) {
rb_vm_lock_enter_body(lev APPEND_LOCATION_PARAMS);
}
}
static inline void
rb_vm_lock_enter_nb(unsigned int *lev, const char *file, int line)
{
RB_DEBUG_COUNTER_INC(vm_sync_lock_enter_nb);
if (rb_multi_ractor_p()) {
rb_vm_lock_enter_body_nb(lev APPEND_LOCATION_PARAMS);
}
}
static inline void
rb_vm_lock_leave_nb(unsigned int *lev, const char *file, int line)
{
if (rb_multi_ractor_p()) {
rb_vm_lock_leave_body_nb(lev APPEND_LOCATION_PARAMS);
}
}
static inline void
rb_vm_lock_leave(unsigned int *lev, const char *file, int line)
{
if (rb_multi_ractor_p()) {
rb_vm_lock_leave_body(lev APPEND_LOCATION_PARAMS);
}
}
static inline void
rb_vm_lock_enter_cr(struct rb_ractor_struct *cr, unsigned int *levp, const char *file, int line)
{
RB_DEBUG_COUNTER_INC(vm_sync_lock_enter_cr);
rb_vm_lock_enter_body_cr(cr, levp APPEND_LOCATION_PARAMS);
}
static inline void
rb_vm_lock_leave_cr(struct rb_ractor_struct *cr, unsigned int *levp, const char *file, int line)
{
rb_vm_lock_leave_body(levp APPEND_LOCATION_PARAMS);
}
#define RB_VM_LOCKED_P() rb_vm_locked_p()
#define RB_VM_LOCK() rb_vm_lock(__FILE__, __LINE__)
#define RB_VM_UNLOCK() rb_vm_unlock(__FILE__, __LINE__)
#define RB_VM_LOCK_ENTER_CR_LEV(cr, levp) rb_vm_lock_enter_cr(cr, levp, __FILE__, __LINE__)
#define RB_VM_LOCK_LEAVE_CR_LEV(cr, levp) rb_vm_lock_leave_cr(cr, levp, __FILE__, __LINE__)
#define RB_VM_LOCK_ENTER_LEV(levp) rb_vm_lock_enter(levp, __FILE__, __LINE__)
#define RB_VM_LOCK_LEAVE_LEV(levp) rb_vm_lock_leave(levp, __FILE__, __LINE__)
#define RB_VM_LOCK_ENTER() { unsigned int _lev; RB_VM_LOCK_ENTER_LEV(&_lev);
#define RB_VM_LOCK_LEAVE() RB_VM_LOCK_LEAVE_LEV(&_lev); }
#define RB_VM_LOCKING() \
for (unsigned int vm_locking_level, vm_locking_do = (RB_VM_LOCK_ENTER_LEV(&vm_locking_level), 1); \
vm_locking_do; RB_VM_LOCK_LEAVE_LEV(&vm_locking_level), vm_locking_do = 0)
#define RB_VM_LOCK_ENTER_LEV_NB(levp) rb_vm_lock_enter_nb(levp, __FILE__, __LINE__)
#define RB_VM_LOCK_LEAVE_LEV_NB(levp) rb_vm_lock_leave_nb(levp, __FILE__, __LINE__)
#define RB_VM_LOCK_ENTER_NO_BARRIER() { unsigned int _lev; RB_VM_LOCK_ENTER_LEV_NB(&_lev);
#define RB_VM_LOCK_LEAVE_NO_BARRIER() RB_VM_LOCK_LEAVE_LEV_NB(&_lev); }
#define RB_VM_LOCKING_NO_BARRIER() \
for (unsigned int vm_locking_level, vm_locking_do = (RB_VM_LOCK_ENTER_LEV_NB(&vm_locking_level), 1); \
vm_locking_do; RB_VM_LOCK_LEAVE_LEV_NB(&vm_locking_level), vm_locking_do = 0)
#if RUBY_DEBUG > 0
void RUBY_ASSERT_vm_locking(void);
void RUBY_ASSERT_vm_unlocking(void);
#define ASSERT_vm_locking() RUBY_ASSERT_vm_locking()
#define ASSERT_vm_unlocking() RUBY_ASSERT_vm_unlocking()
#else
#define ASSERT_vm_locking()
#define ASSERT_vm_unlocking()
#endif
#endif // RUBY_VM_SYNC_H