Begin changes to sync2

4 files changed, 248 insertions, 162 deletions

diff --git a/core/sync/sync2/atomic.odin b/core/sync/sync2/atomic.odin
index fa86ec352..efefc8025 100644
--- a/core/sync/sync2/atomic.odin
+++ b/core/sync/sync2/atomic.odin
@@ -56,6 +56,7 @@ atomic_exchange_release :: intrinsics.atomic_xchg_rel;
 atomic_exchange_acqrel  :: intrinsics.atomic_xchg_acqrel;
 atomic_exchange_relaxed :: intrinsics.atomic_xchg_relaxed;
 
+// Returns value and optional ok boolean
 atomic_compare_exchange_strong                     :: intrinsics.atomic_cxchg;
 atomic_compare_exchange_strong_acquire             :: intrinsics.atomic_cxchg_acq;
 atomic_compare_exchange_strong_release             :: intrinsics.atomic_cxchg_rel;
@@ -66,6 +67,7 @@ atomic_compare_exchange_strong_failacquire         :: intrinsics.atomic_cxchg_fa
 atomic_compare_exchange_strong_acquire_failrelaxed :: intrinsics.atomic_cxchg_acq_failrelaxed;
 atomic_compare_exchange_strong_acqrel_failrelaxed  :: intrinsics.atomic_cxchg_acqrel_failrelaxed;
 
+// Returns value and optional ok boolean
 atomic_compare_exchange_weak                     :: intrinsics.atomic_cxchgweak;
 atomic_compare_exchange_weak_acquire             :: intrinsics.atomic_cxchgweak_acq;
 atomic_compare_exchange_weak_release             :: intrinsics.atomic_cxchgweak_rel;
diff --git a/core/sync/sync2/primitives.odin b/core/sync/sync2/primitives.odin
index 1ed83f706..e524586ec 100644
--- a/core/sync/sync2/primitives.odin
+++ b/core/sync/sync2/primitives.odin
@@ -15,7 +15,7 @@ mutex_lock :: proc(m: ^Mutex) {
 	_mutex_lock(m);
 }
 
-// mutex_lock unlocks m
+// mutex_unlock unlocks m
 mutex_unlock :: proc(m: ^Mutex) {
 	_mutex_unlock(m);
 }
@@ -103,7 +103,7 @@ rw_mutex_shared_guard :: proc(m: ^RW_Mutex) -> bool {
 
 
 
-// A Recusrive_Mutex is a recursive mutual exclusion lock
+// A Recursive_Mutex is a recursive mutual exclusion lock
 // The zero value for a Recursive_Mutex is an unlocked mutex
 //
 // A Recursive_Mutex must not be copied after first use
diff --git a/core/sync/sync2/primitives_atomic.odin b/core/sync/sync2/primitives_atomic.odin
index 7043f8c84..aed01eb1f 100644
--- a/core/sync/sync2/primitives_atomic.odin
+++ b/core/sync/sync2/primitives_atomic.odin
@@ -1,159 +1,193 @@
-//+build linux, darwin, freebsd
-//+private
 package sync2
 
-when !#config(ODIN_SYNC_USE_PTHREADS, true) {
-
 import "core:time"
 import "core:runtime"
 
-_Mutex_State :: enum i32 {
+Atomic_Mutex_State :: enum i32 {
 	Unlocked = 0,
 	Locked   = 1,
 	Waiting  = 2,
 }
-_Mutex :: struct {
-	state: _Mutex_State,
-}
 
-_mutex_lock :: proc(m: ^Mutex) {
-	if atomic_xchg_rel(&m.impl.state, .Unlocked) != .Unlocked {
-		_mutex_unlock_slow(m);
-	}
-}
-
-_mutex_unlock :: proc(m: ^Mutex) {
-	switch atomic_xchg_rel(&m.impl.state, .Unlocked) {
-	case .Unlocked:
-		unreachable();
-	case .Locked:
-		// Okay
-	case .Waiting:
-		_mutex_unlock_slow(m);
-	}
-}
 
-_mutex_try_lock :: proc(m: ^Mutex) -> bool {
-	_, ok := atomic_cxchg_acq(&m.impl.state, .Unlocked, .Locked);
-	return ok;
+// An Atomic_Mutex is a mutual exclusion lock
+// The zero value for a Atomic_Mutex is an unlocked mutex
+//
+// An Atomic_Mutex must not be copied after first use
+Atomic_Mutex :: struct {
+	state: Atomic_Mutex_State,
 }
 
-
-@(cold)
-_mutex_lock_slow :: proc(m: ^Mutex, curr_state: _Mutex_State) {
-	new_state := curr_state; // Make a copy of it
-
-	spin_lock: for spin in 0..<i32(100) {
-		state, ok := atomic_cxchgweak_acq(&m.impl.state, .Unlocked, new_state);
-		if ok {
-			return;
+// atomic_mutex_lock locks m
+atomic_mutex_lock :: proc(m: ^Atomic_Mutex) {
+	@(cold)
+	lock_slow :: proc(m: ^Atomic_Mutex, curr_state: Atomic_Mutex_State) {
+		new_state := curr_state; // Make a copy of it
+
+		spin_lock: for spin in 0..<i32(100) {
+			state, ok := atomic_compare_exchange_weak_acquire(&m.state, .Unlocked, new_state);
+			if ok {
+				return;
+			}
+
+			if state == .Waiting {
+				break spin_lock;
+			}
+
+			for i := min(spin+1, 32); i > 0; i -= 1 {
+				cpu_relax();
+			}
 		}
 
-		if state == .Waiting {
-			break spin_lock;
-		}
+		for {
+			if atomic_exchange_acquire(&m.state, .Waiting) == .Unlocked {
+				return;
+			}
 
-		for i := min(spin+1, 32); i > 0; i -= 1 {
+			// TODO(bill): Use a Futex here for Linux to improve performance and error handling
 			cpu_relax();
 		}
 	}
 
-	for {
-		if atomic_xchg_acq(&m.impl.state, .Waiting) == .Unlocked {
-			return;
-		}
 
+	switch v := atomic_exchange_acquire(&m.state, .Locked); v {
+	case .Unlocked:
+		// Okay
+	case: fallthrough;
+	case .Locked, .Waiting:
+		lock_slow(m, v);
+	}
+}
+
+// atomic_mutex_unlock unlocks m
+atomic_mutex_unlock :: proc(m: ^Atomic_Mutex) {
+	@(cold)
+	unlock_slow :: proc(m: ^Atomic_Mutex) {
 		// TODO(bill): Use a Futex here for Linux to improve performance and error handling
-		cpu_relax();
 	}
+
+
+	switch atomic_exchange_release(&m.state, .Unlocked) {
+	case .Unlocked:
+		unreachable();
+	case .Locked:
+		// Okay
+	case .Waiting:
+		unlock_slow(m);
+	}
+}
+
+// atomic_mutex_try_lock tries to lock m, will return true on success, and false on failure
+atomic_mutex_try_lock :: proc(m: ^Atomic_Mutex) -> bool {
+	_, ok := atomic_compare_exchange_strong_acquire(&m.state, .Unlocked, .Locked);
+	return ok;
 }
 
 
-@(cold)
-_mutex_unlock_slow :: proc(m: ^Mutex) {
-	// TODO(bill): Use a Futex here for Linux to improve performance and error handling
+// Example:
+//
+// if atomic_mutex_guard(&m) {
+//         ...
+// }
+//
+@(deferred_in=atomic_mutex_unlock)
+atomic_mutex_guard :: proc(m: ^Atomic_Mutex) -> bool {
+	atomic_mutex_lock(m);
+	return true;
 }
 
 
-RW_Mutex_State :: distinct uint;
-RW_Mutex_State_Half_Width :: size_of(RW_Mutex_State)*8/2;
-RW_Mutex_State_Is_Writing :: RW_Mutex_State(1);
-RW_Mutex_State_Writer     :: RW_Mutex_State(1)<<1;
-RW_Mutex_State_Reader     :: RW_Mutex_State(1)<<RW_Mutex_State_Half_Width;
+Atomic_RW_Mutex_State :: distinct uint;
+Atomic_RW_Mutex_State_Half_Width :: size_of(Atomic_RW_Mutex_State)*8/2;
+Atomic_RW_Mutex_State_Is_Writing :: Atomic_RW_Mutex_State(1);
+Atomic_RW_Mutex_State_Writer     :: Atomic_RW_Mutex_State(1)<<1;
+Atomic_RW_Mutex_State_Reader     :: Atomic_RW_Mutex_State(1)<<Atomic_RW_Mutex_State_Half_Width;
 
-RW_Mutex_State_Writer_Mask :: RW_Mutex_State(1<<(RW_Mutex_State_Half_Width-1) - 1) << 1;
-RW_Mutex_State_Reader_Mask :: RW_Mutex_State(1<<(RW_Mutex_State_Half_Width-1) - 1) << RW_Mutex_State_Half_Width;
+Atomic_RW_Mutex_State_Writer_Mask :: Atomic_RW_Mutex_State(1<<(Atomic_RW_Mutex_State_Half_Width-1) - 1) << 1;
+Atomic_RW_Mutex_State_Reader_Mask :: Atomic_RW_Mutex_State(1<<(Atomic_RW_Mutex_State_Half_Width-1) - 1) << Atomic_RW_Mutex_State_Half_Width;
 
 
-_RW_Mutex :: struct {
-	state: RW_Mutex_State,
-	mutex: Mutex,
-	sema:  Sema,
+// An Atomic_RW_Mutex is a reader/writer mutual exclusion lock
+// The lock can be held by any arbitrary number of readers or a single writer
+// The zero value for an Atomic_RW_Mutex is an unlocked mutex
+//
+// An Atomic_RW_Mutex must not be copied after first use
+Atomic_RW_Mutex :: struct {
+	state: Atomic_RW_Mutex_State,
+	mutex: Atomic_Mutex,
+	sema:  Atomic_Sema,
 }
 
-_rw_mutex_lock :: proc(rw: ^RW_Mutex) {
-	_ = atomic_add(&rw.impl.state, RW_Mutex_State_Writer);
-	mutex_lock(&rw.impl.mutex);
+// atomic_rw_mutex_lock locks rw for writing (with a single writer)
+// If the mutex is already locked for reading or writing, the mutex blocks until the mutex is available.
+atomic_rw_mutex_lock :: proc(rw: ^Atomic_RW_Mutex) {
+	_ = atomic_add(&rw.state, Atomic_RW_Mutex_State_Writer);
+	atomic_mutex_lock(&rw.mutex);
 
-	state := atomic_or(&rw.impl.state, RW_Mutex_State_Writer);
-	if state & RW_Mutex_State_Reader_Mask != 0 {
-		sema_wait(&rw.impl.sema);
+	state := atomic_or(&rw.state, Atomic_RW_Mutex_State_Writer);
+	if state & Atomic_RW_Mutex_State_Reader_Mask != 0 {
+		atomic_sema_wait(&rw.sema);
 	}
 }
 
-_rw_mutex_unlock :: proc(rw: ^RW_Mutex) {
-	_ = atomic_and(&rw.impl.state, ~RW_Mutex_State_Is_Writing);
-	mutex_unlock(&rw.impl.mutex);
+// atomic_rw_mutex_unlock unlocks rw for writing (with a single writer)
+atomic_rw_mutex_unlock :: proc(rw: ^Atomic_RW_Mutex) {
+	_ = atomic_and(&rw.state, ~Atomic_RW_Mutex_State_Is_Writing);
+	atomic_mutex_unlock(&rw.mutex);
 }
 
-_rw_mutex_try_lock :: proc(rw: ^RW_Mutex) -> bool {
-	if mutex_try_lock(&rw.impl.mutex) {
-		state := atomic_load(&rw.impl.state);
-		if state & RW_Mutex_State_Reader_Mask == 0 {
-			_ = atomic_or(&rw.impl.state, RW_Mutex_State_Is_Writing);
+// atomic_rw_mutex_try_lock tries to lock rw for writing (with a single writer)
+atomic_rw_mutex_try_lock :: proc(rw: ^Atomic_RW_Mutex) -> bool {
+	if atomic_mutex_try_lock(&rw.mutex) {
+		state := atomic_load(&rw.state);
+		if state & Atomic_RW_Mutex_State_Reader_Mask == 0 {
+			_ = atomic_or(&rw.state, Atomic_RW_Mutex_State_Is_Writing);
 			return true;
 		}
 
-		mutex_unlock(&rw.impl.mutex);
+		atomic_mutex_unlock(&rw.mutex);
 	}
 	return false;
 }
 
-_rw_mutex_shared_lock :: proc(rw: ^RW_Mutex) {
-	state := atomic_load(&rw.impl.state);
-	for state & (RW_Mutex_State_Is_Writing|RW_Mutex_State_Writer_Mask) == 0 {
+// atomic_rw_mutex_shared_lock locks rw for reading (with arbitrary number of readers)
+atomic_rw_mutex_shared_lock :: proc(rw: ^Atomic_RW_Mutex) {
+	state := atomic_load(&rw.state);
+	for state & (Atomic_RW_Mutex_State_Is_Writing|Atomic_RW_Mutex_State_Writer_Mask) == 0 {
 		ok: bool;
-		state, ok = atomic_cxchgweak(&rw.impl.state, state, state + RW_Mutex_State_Reader);
+		state, ok = atomic_compare_exchange_weak(&rw.state, state, state + Atomic_RW_Mutex_State_Reader);
 		if ok {
 			return;
 		}
 	}
 
-	mutex_lock(&rw.impl.mutex);
-	_ = atomic_add(&rw.impl.state, RW_Mutex_State_Reader);
-	mutex_unlock(&rw.impl.mutex);
+	atomic_mutex_lock(&rw.mutex);
+	_ = atomic_add(&rw.state, Atomic_RW_Mutex_State_Reader);
+	atomic_mutex_unlock(&rw.mutex);
 }
 
-_rw_mutex_shared_unlock :: proc(rw: ^RW_Mutex) {
-	state := atomic_sub(&rw.impl.state, RW_Mutex_State_Reader);
+// atomic_rw_mutex_shared_unlock unlocks rw for reading (with arbitrary number of readers)
+atomic_rw_mutex_shared_unlock :: proc(rw: ^Atomic_RW_Mutex) {
+	state := atomic_sub(&rw.state, Atomic_RW_Mutex_State_Reader);
 
-	if (state & RW_Mutex_State_Reader_Mask == RW_Mutex_State_Reader) &&
-	   (state & RW_Mutex_State_Is_Writing != 0) {
-	   	sema_post(&rw.impl.sema);
+	if (state & Atomic_RW_Mutex_State_Reader_Mask == Atomic_RW_Mutex_State_Reader) &&
+	   (state & Atomic_RW_Mutex_State_Is_Writing != 0) {
+	   	atomic_sema_post(&rw.sema);
 	}
 }
 
-_rw_mutex_try_shared_lock :: proc(rw: ^RW_Mutex) -> bool {
-	state := atomic_load(&rw.impl.state);
-	if state & (RW_Mutex_State_Is_Writing|RW_Mutex_State_Writer_Mask) == 0 {
-		_, ok := atomic_cxchg(&rw.impl.state, state, state + RW_Mutex_State_Reader);
+// atomic_rw_mutex_try_shared_lock tries to lock rw for reading (with arbitrary number of readers)
+atomic_rw_mutex_try_shared_lock :: proc(rw: ^Atomic_RW_Mutex) -> bool {
+	state := atomic_load(&rw.state);
+	if state & (Atomic_RW_Mutex_State_Is_Writing|Atomic_RW_Mutex_State_Writer_Mask) == 0 {
+		_, ok := atomic_compare_exchange_strong(&rw.state, state, state + Atomic_RW_Mutex_State_Reader);
 		if ok {
 			return true;
 		}
 	}
-	if mutex_try_lock(&rw.impl.mutex) {
-		_ = atomic_add(&rw.impl.state, RW_Mutex_State_Reader);
-		mutex_unlock(&rw.impl.mutex);
+	if atomic_mutex_try_lock(&rw.mutex) {
+		_ = atomic_add(&rw.state, Atomic_RW_Mutex_State_Reader);
+		atomic_mutex_unlock(&rw.mutex);
 		return true;
 	}
 
@@ -161,127 +195,177 @@ _rw_mutex_try_shared_lock :: proc(rw: ^RW_Mutex) -> bool {
 }
 
 
-_Recursive_Mutex :: struct {
+// Example:
+//
+// if atomic_rw_mutex_guard(&m) {
+//         ...
+// }
+//
+@(deferred_in=atomic_rw_mutex_unlock)
+atomic_rw_mutex_guard :: proc(m: ^Atomic_RW_Mutex) -> bool {
+	atomic_rw_mutex_lock(m);
+	return true;
+}
+
+// Example:
+//
+// if atomic_rw_mutex_shared_guard(&m) {
+//         ...
+// }
+//
+@(deferred_in=atomic_rw_mutex_shared_unlock)
+atomic_rw_mutex_shared_guard :: proc(m: ^Atomic_RW_Mutex) -> bool {
+	atomic_rw_mutex_shared_lock(m);
+	return true;
+}
+
+
+
+
+// An Atomic_Recursive_Mutex is a recursive mutual exclusion lock
+// The zero value for a Recursive_Mutex is an unlocked mutex
+//
+// An Atomic_Recursive_Mutex must not be copied after first use
+Atomic_Recursive_Mutex :: struct {
 	owner:     int,
 	recursion: int,
 	mutex: Mutex,
 }
 
-_recursive_mutex_lock :: proc(m: ^Recursive_Mutex) {
+atomic_recursive_mutex_lock :: proc(m: ^Atomic_Recursive_Mutex) {
 	tid := runtime.current_thread_id();
-	if tid != m.impl.owner {
-		mutex_lock(&m.impl.mutex);
+	if tid != m.owner {
+		mutex_lock(&m.mutex);
 	}
 	// inside the lock
-	m.impl.owner = tid;
-	m.impl.recursion += 1;
+	m.owner = tid;
+	m.recursion += 1;
 }
 
-_recursive_mutex_unlock :: proc(m: ^Recursive_Mutex) {
+atomic_recursive_mutex_unlock :: proc(m: ^Atomic_Recursive_Mutex) {
 	tid := runtime.current_thread_id();
-	assert(tid == m.impl.owner);
-	m.impl.recursion -= 1;
-	recursion := m.impl.recursion;
+	assert(tid == m.owner);
+	m.recursion -= 1;
+	recursion := m.recursion;
 	if recursion == 0 {
-		m.impl.owner = 0;
+		m.owner = 0;
 	}
 	if recursion == 0 {
-		mutex_unlock(&m.impl.mutex);
+		mutex_unlock(&m.mutex);
 	}
 	// outside the lock
 
 }
 
-_recursive_mutex_try_lock :: proc(m: ^Recursive_Mutex) -> bool {
+atomic_recursive_mutex_try_lock :: proc(m: ^Atomic_Recursive_Mutex) -> bool {
 	tid := runtime.current_thread_id();
-	if m.impl.owner == tid {
-		return mutex_try_lock(&m.impl.mutex);
+	if m.owner == tid {
+		return mutex_try_lock(&m.mutex);
 	}
-	if !mutex_try_lock(&m.impl.mutex) {
+	if !mutex_try_lock(&m.mutex) {
 		return false;
 	}
 	// inside the lock
-	m.impl.owner = tid;
-	m.impl.recursion += 1;
+	m.owner = tid;
+	m.recursion += 1;
 	return true;
 }
 
 
+// Example:
+//
+// if atomic_recursive_mutex_guard(&m) {
+//         ...
+// }
+//
+@(deferred_in=atomic_recursive_mutex_unlock)
+atomic_recursive_mutex_guard :: proc(m: ^Atomic_Recursive_Mutex) -> bool {
+	atomic_recursive_mutex_lock(m);
+	return true;
+}
 
 
 
+
+@(private="file")
 Queue_Item :: struct {
 	next: ^Queue_Item,
 	futex: i32,
 }
 
+@(private="file")
 queue_item_wait :: proc(item: ^Queue_Item) {
-	for atomic_load_acq(&item.futex) == 0 {
+	for atomic_load_acquire(&item.futex) == 0 {
 		// TODO(bill): Use a Futex here for Linux to improve performance and error handling
 		cpu_relax();
 	}
 }
+@(private="file")
 queue_item_signal :: proc(item: ^Queue_Item) {
-	atomic_store_rel(&item.futex, 1);
+	atomic_store_release(&item.futex, 1);
 	// TODO(bill): Use a Futex here for Linux to improve performance and error handling
 }
 
 
-_Cond :: struct {
-	queue_mutex: Mutex,
+// Atomic_Cond implements a condition variable, a rendezvous point for threads
+// waiting for signalling the occurence of an event
+//
+// An Atomic_Cond must not be copied after first use
+Atomic_Cond :: struct {
+	queue_mutex: Atomic_Mutex,
 	queue_head:  ^Queue_Item,
 	pending:     bool,
 }
 
-_cond_wait :: proc(c: ^Cond, m: ^Mutex) {
+atomic_cond_wait :: proc(c: ^Atomic_Cond, m: ^Atomic_Mutex) {
 	waiter := &Queue_Item{};
 
-	mutex_lock(&c.impl.queue_mutex);
-	waiter.next = c.impl.queue_head;
-	c.impl.queue_head = waiter;
+	atomic_mutex_lock(&c.queue_mutex);
+	waiter.next = c.queue_head;
+	c.queue_head = waiter;
 
-	atomic_store(&c.impl.pending, true);
-	mutex_unlock(&c.impl.queue_mutex);
+	atomic_store(&c.pending, true);
+	atomic_mutex_unlock(&c.queue_mutex);
 
-	mutex_unlock(m);
+	atomic_mutex_unlock(m);
 	queue_item_wait(waiter);
-	mutex_lock(m);
+	atomic_mutex_lock(m);
 }
 
-_cond_wait_with_timeout :: proc(c: ^Cond, m: ^Mutex, timeout: time.Duration) -> bool {
+atomic_cond_wait_with_timeout :: proc(c: ^Atomic_Cond, m: ^Atomic_Mutex, timeout: time.Duration) -> bool {
 	// TODO(bill): _cond_wait_with_timeout for unix
 	return false;
 }
 
-_cond_signal :: proc(c: ^Cond) {
-	if !atomic_load(&c.impl.pending) {
+atomic_cond_signal :: proc(c: ^Atomic_Cond) {
+	if !atomic_load(&c.pending) {
 		return;
 	}
 
-	mutex_lock(&c.impl.queue_mutex);
-	waiter := c.impl.queue_head;
-	if c.impl.queue_head != nil {
-		c.impl.queue_head = c.impl.queue_head.next;
+	atomic_mutex_lock(&c.queue_mutex);
+	waiter := c.queue_head;
+	if c.queue_head != nil {
+		c.queue_head = c.queue_head.next;
 	}
-	atomic_store(&c.impl.pending, c.impl.queue_head != nil);
-	mutex_unlock(&c.impl.queue_mutex);
+	atomic_store(&c.pending, c.queue_head != nil);
+	atomic_mutex_unlock(&c.queue_mutex);
 
 	if waiter != nil {
 		queue_item_signal(waiter);
 	}
 }
 
-_cond_broadcast :: proc(c: ^Cond) {
-	if !atomic_load(&c.impl.pending) {
+atomic_cond_broadcast :: proc(c: ^Atomic_Cond) {
+	if !atomic_load(&c.pending) {
 		return;
 	}
 
-	atomic_store(&c.impl.pending, false);
+	atomic_store(&c.pending, false);
 
-	mutex_lock(&c.impl.queue_mutex);
-	waiters := c.impl.queue_head;
-	c.impl.queue_head = nil;
-	mutex_unlock(&c.impl.queue_mutex);
+	atomic_mutex_lock(&c.queue_mutex);
+	waiters := c.queue_head;
+	c.queue_head = nil;
+	atomic_mutex_unlock(&c.queue_mutex);
 
 	for waiters != nil {
 		queue_item_signal(waiters);
@@ -289,35 +373,35 @@ _cond_broadcast :: proc(c: ^Cond) {
 	}
 }
 
-_Sema :: struct {
-	mutex: Mutex,
-	cond:  Cond,
+// When waited upon, blocks until the internal count is greater than zero, then subtracts one.
+// Posting to the semaphore increases the count by one, or the provided amount.
+//
+// An Atomic_Sema must not be copied after first use
+Atomic_Sema :: struct {
+	mutex: Atomic_Mutex,
+	cond:  Atomic_Cond,
 	count: int,
 }
 
-_sema_wait :: proc(s: ^Sema) {
-	mutex_lock(&s.impl.mutex);
-	defer mutex_unlock(&s.impl.mutex);
+atomic_sema_wait :: proc(s: ^Atomic_Sema) {
+	atomic_mutex_lock(&s.mutex);
+	defer atomic_mutex_unlock(&s.mutex);
 
-	for s.impl.count == 0 {
-		cond_wait(&s.impl.cond, &s.impl.mutex);
+	for s.count == 0 {
+		atomic_cond_wait(&s.cond, &s.mutex);
 	}
 
-	s.impl.count -= 1;
-	if s.impl.count > 0 {
-		cond_signal(&s.impl.cond);
+	s.count -= 1;
+	if s.count > 0 {
+		atomic_cond_signal(&s.cond);
 	}
 }
 
-_sema_post :: proc(s: ^Sema, count := 1) {
-	mutex_lock(&s.impl.mutex);
-	defer mutex_unlock(&s.impl.mutex);
+atomic_sema_post :: proc(s: ^Atomic_Sema, count := 1) {
+	atomic_mutex_lock(&s.mutex);
+	defer atomic_mutex_unlock(&s.mutex);
 
-	s.impl.count += count;
-	cond_signal(&s.impl.cond);
+	s.count += count;
+	atomic_cond_signal(&s.cond);
 }
 
-
-
-
-} // !ODIN_SYNC_USE_PTHREADS
diff --git a/core/sync/sync2/primitives_pthreads.odin b/core/sync/sync2/primitives_pthreads.odin
index 5fd43d871..7e45e0565 100644
--- a/core/sync/sync2/primitives_pthreads.odin
+++ b/core/sync/sync2/primitives_pthreads.odin
@@ -1,4 +1,4 @@
-//+build linux, darwin, freebsd
+//+build linux, freebsd
 //+private
 package sync2