Changeset 4069faad for libcfa/src/bits

Timestamp:

May 1, 2020, 12:37:30 PM (5 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

d45ed83

Parents:

9987d79

Message:

Fix error in benchmark where the wrong fd was used.
Changed behcnmark to use seperate cluster for I/O.
Changed some debug prints to use new versions with groups.
Fixed halting race condition leading to deadlock.

File:

• libcfa/src/bits/locks.hfa (modified) (2 diffs)

libcfa/src/bits/locks.hfa

@@ -113 +113 @@
 
         struct __bin_sem_t {
-                bool                    signaled;
                 pthread_mutex_t         lock;
                 pthread_cond_t          cond;
+                int                     val;
         };
 
         static inline void ?{}(__bin_sem_t & this) with( this ) {
-                signaled = false;
                 pthread_mutex_init(&lock, NULL);
                 pthread_cond_init (&cond, NULL);
+                val = 0;
         }
 
@@ -132 +132 @@
                 verify(__cfaabi_dbg_in_kernel());
                 pthread_mutex_lock(&lock);
-                        if(!signaled) {   // this must be a loop, not if!
+                        while(val < 1) {
                                 pthread_cond_wait(&cond, &lock);
                         }
-                        signaled = false;
+                        val -= 1;
                 pthread_mutex_unlock(&lock);
         }
 
         static inline bool post(__bin_sem_t & this) with( this ) {
+                bool needs_signal = false;
+
                 pthread_mutex_lock(&lock);
-                        bool needs_signal = !signaled;
-                        signaled = true;
+                        if(val < 1) {
+                                val += 1;
+                                pthread_cond_signal(&cond);
+                                needs_signal = true;
+                        }
                 pthread_mutex_unlock(&lock);
-
-                if (needs_signal) pthread_cond_signal(&cond);
 
                 return needs_signal;