Changeset eba74ba for src/libcfa/bits/locks.h

Timestamp:

May 25, 2018, 2:51:06 PM (6 years ago)

Author:

Aaron Moss <a3moss@…>

Branches:

new-env, with_gc

Children:

cdc4d43

Parents:

3ef35bd (diff), 58e822a (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge remote-tracking branch 'origin/master' into with_gc

File:

• src/libcfa/bits/locks.h (modified) (4 diffs)

src/libcfa/bits/locks.h

@@ -39 +39 @@
 #endif
 
-#if __SIZEOF_SIZE_T__ == 8
-        #define __lock_test_and_test_and_set( lock ) (lock) == 0 && __sync_lock_test_and_set_8( &(lock), 1 ) == 0
-        #define __lock_release( lock ) __sync_lock_release_8( &(lock) );
-#elif __SIZEOF_SIZE_T__ == 4
-        #define __lock_test_and_test_and_set( lock ) (lock) == 0 && __sync_lock_test_and_set_4( &(lock), 1 ) == 0
-        #define __lock_release( lock ) __sync_lock_release_4( &(lock) );
-#else
-        #error unsupported architecture
-#endif
-
 struct __spinlock_t {
-        __ALIGN__ volatile size_t lock;
+        // Wrap in struct to prevent false sharing with debug info
+        struct {
+                // Align lock on 128-bit boundary
+                __ALIGN__ volatile _Bool lock;
+        };
         #ifdef __CFA_DEBUG__
+                // previous function to acquire the lock
                 const char * prev_name;
+                // previous thread to acquire the lock
                 void* prev_thrd;
         #endif
@@ -78 +74 @@
         // Lock the spinlock, return false if already acquired
         static inline _Bool try_lock  ( __spinlock_t & this __cfaabi_dbg_ctx_param2 ) {
-                _Bool result = __lock_test_and_test_and_set( this.lock );
+                _Bool result = (this.lock == 0) && (__atomic_test_and_set( &this.lock, __ATOMIC_ACQUIRE ) == 0);
                 if( result ) {
                         disable_interrupts();
@@ -94 +90 @@
 
                 for ( unsigned int i = 1;; i += 1 ) {
-                        if ( __lock_test_and_test_and_set( this.lock ) ) break;
+                        if ( (this.lock == 0) && (__atomic_test_and_set( &this.lock, __ATOMIC_ACQUIRE ) == 0) ) break;
                         #ifndef NOEXPBACK
                                 // exponential spin
@@ -112 +108 @@
         }
 
-        // // Lock the spinlock, yield if already acquired
-        // static inline void lock_yield( __spinlock_t & this __cfaabi_dbg_ctx_param2 ) {
-        //      for ( unsigned int i = 1;; i += 1 ) {
-        //              if ( __lock_test_and_test_and_set( this.lock ) ) break;
-        //              yield( i );
-        //      }
-        //      disable_interrupts();
-        //      __cfaabi_dbg_debug_do(
-        //              this.prev_name = caller;
-        //              this.prev_thrd = this_thread;
-        //      )
-        // }
-
         static inline void unlock( __spinlock_t & this ) {
                 enable_interrupts_noPoll();
-                __lock_release( this.lock );
+                __atomic_clear( &this.lock, __ATOMIC_RELEASE );
         }
 #endif