1 // Copyright 2010 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
10 runtime_initlock(Lock *l)
13 if(sem_init(&l->sem, 0, 0) != 0)
14 runtime_throw("sem_init failed");
18 runtime_xadd(uint32 volatile *val, int32 delta)
25 if(runtime_cas(val, oval, nval))
30 // noinline so that runtime_lock doesn't have to split the stack.
31 static void runtime_lock_full(Lock *l) __attribute__ ((noinline));
34 runtime_lock_full(Lock *l)
37 if(sem_wait(&l->sem) == 0)
40 runtime_throw("sem_wait failed");
49 runtime_throw("lock count");
53 if(runtime_xadd(&l->key, 1) > 1) // someone else has it; wait
57 static void runtime_unlock_full(Lock *l) __attribute__ ((noinline));
60 runtime_unlock_full(Lock *l)
62 if(sem_post(&l->sem) != 0)
63 runtime_throw("sem_post failed");
67 runtime_unlock(Lock *l)
72 runtime_throw("lock count");
75 if(runtime_xadd(&l->key, -1) > 0) // someone else is waiting
76 runtime_unlock_full(l);
80 runtime_destroylock(Lock *l)
85 #ifndef HAVE_SYNC_BOOL_COMPARE_AND_SWAP_4
87 // For targets which don't have the required sync support. Really
88 // this should be provided by gcc itself. FIXME.
90 static pthread_mutex_t sync_lock = PTHREAD_MUTEX_INITIALIZER;
93 __sync_bool_compare_and_swap_4(uint32*, uint32, uint32)
94 __attribute__((visibility("hidden")));
97 __sync_bool_compare_and_swap_4(uint32* ptr, uint32 old, uint32 new)
102 i = pthread_mutex_lock(&sync_lock);
112 i = pthread_mutex_unlock(&sync_lock);