diff options
Diffstat (limited to 'src/kernel/lib/mutex.c')
-rw-r--r-- | src/kernel/lib/mutex.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/src/kernel/lib/mutex.c b/src/kernel/lib/mutex.c new file mode 100644 index 0000000..f3ed11f --- /dev/null +++ b/src/kernel/lib/mutex.c @@ -0,0 +1,23 @@ +#include "mutex.h" +#include <task/task.h> + +static uint32_t atomic_exchange(uint32_t* ptr, uint32_t newval) { + uint32_t r; + asm volatile("xchg (%%ecx), %%eax" : "=a"(r) : "c"(ptr), "a"(newval)); + return r; +} + +void mutex_lock(uint32_t* mutex) { + while (atomic_exchange(mutex, MUTEX_LOCKED) == MUTEX_LOCKED) { + thread_sleep(1); + } +} + +int mutex_lockE(uint32_t* mutex) { + if (atomic_exchange(mutex, MUTEX_LOCKED) == MUTEX_LOCKED) return 0; + return 1; +} + +void mutex_unlock(uint32_t* mutex) { + *mutex = MUTEX_UNLOCKED; +} |