Changeset d30e3eb for libcfa/src/concurrency/locks.hfa

Timestamp:

Mar 24, 2023, 4:44:46 PM (13 months ago)

Author:

caparson <caparson@…>

Branches:

ADT, ast-experimental, master

Children:

1633e04

Parents:

de934c7

Message:

cleaned up exp_backoff lock and rewrote parts of channels to improve performance

File:

• libcfa/src/concurrency/locks.hfa (modified) (5 diffs)

libcfa/src/concurrency/locks.hfa

@@ -253 +253 @@
 static inline void on_wakeup(clh_lock & this, size_t recursion ) { lock(this); }
 
-
 //-----------------------------------------------------------------------------
 // Exponential backoff then block lock
@@ -272 +271 @@
         this.lock_value = 0;
 }
-static inline void ^?{}( exp_backoff_then_block_lock & this ) {}
-// static inline void ?{}( exp_backoff_then_block_lock & this, exp_backoff_then_block_lock this2 ) = void;
-// static inline void ?=?( exp_backoff_then_block_lock & this, exp_backoff_then_block_lock this2 ) = void;
 
 static inline bool internal_try_lock(exp_backoff_then_block_lock & this, size_t & compare_val) with(this) {
-        if (__atomic_compare_exchange_n(&lock_value, &compare_val, 1, false, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED)) {
-                return true;
-        }
-        return false;
+        return __atomic_compare_exchange_n(&lock_value, &compare_val, 1, false, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
 }
 
@@ -286 +279 @@
 
 static inline bool try_lock_contention(exp_backoff_then_block_lock & this) with(this) {
-        if (__atomic_exchange_n(&lock_value, 2, __ATOMIC_ACQUIRE) == 0) {
-                return true;
-        }
-        return false;
+        return !__atomic_exchange_n(&lock_value, 2, __ATOMIC_ACQUIRE);
 }
 
 static inline bool block(exp_backoff_then_block_lock & this) with(this) {
-        lock( spinlock __cfaabi_dbg_ctx2 ); // TODO change to lockfree queue (MPSC)
-        if (lock_value != 2) {
-                unlock( spinlock );
-                return true;
-        }
-        insert_last( blocked_threads, *active_thread() );
-        unlock( spinlock );
+    lock( spinlock __cfaabi_dbg_ctx2 );
+    if (__atomic_load_n( &lock_value, __ATOMIC_SEQ_CST) != 2) {
+        unlock( spinlock );
+        return true;
+    }
+    insert_last( blocked_threads, *active_thread() );
+    unlock( spinlock );
         park( );
         return true;
@@ -307 +297 @@
         size_t compare_val = 0;
         int spin = 4;
+
         // linear backoff
         for( ;; ) {
@@ -324 +315 @@
 static inline void unlock(exp_backoff_then_block_lock & this) with(this) {
     if (__atomic_exchange_n(&lock_value, 0, __ATOMIC_RELEASE) == 1) return;
-        lock( spinlock __cfaabi_dbg_ctx2 );
-        thread$ * t = &try_pop_front( blocked_threads );
-        unlock( spinlock );
-        unpark( t );
+    lock( spinlock __cfaabi_dbg_ctx2 );
+    thread$ * t = &try_pop_front( blocked_threads );
+    unlock( spinlock );
+    unpark( t );
 }