Second Extended Filesystem (ext2) and other improvements (#33)

[lunaix-os.git] / lunaix-os / kernel / ds / mutex.c

diff --git a/lunaix-os/kernel/ds/mutex.c b/lunaix-os/kernel/ds/mutex.c
index 7bfbf10620fe0b8bd6c453d67ddbff00b23b7052..a27c8db6163f36e91e12c719259fce81e1d17548 100644 (file)
--- a/lunaix-os/kernel/ds/mutex.c
+++ b/lunaix-os/kernel/ds/mutex.c
@@ -1,24 +1,65 @@
 #include <lunaix/ds/mutex.h>
 #include <lunaix/process.h>
+#include <lunaix/kpreempt.h>
+
+static inline bool must_inline
+__mutex_check_owner(mutex_t* mutex)
+{
+    return mutex->owner == __current->pid;
+}
+
+static inline void must_inline
+__mutext_lock(mutex_t* mutex)
+{
+    while (atomic_load(&mutex->lk)) {
+        preempt_current();
+    }
+
+    atomic_fetch_add(&mutex->lk, 1);
+    mutex->owner = __current->pid;
+}
+
+static inline void must_inline
+__mutext_unlock(mutex_t* mutex)
+{
+    if (__mutex_check_owner(mutex))
+        atomic_fetch_sub(&mutex->lk, 1);
+}
 
 void
 mutex_lock(mutex_t* mutex)
 {
-    sem_wait(&mutex->sem);
-    mutex->owner = __current->pid;
+    __mutext_lock(mutex);
 }
 
 void
 mutex_unlock(mutex_t* mutex)
 {
-    mutex_unlock_for(mutex, __current->pid);
+    __mutext_unlock(mutex);
 }
 
 void
 mutex_unlock_for(mutex_t* mutex, pid_t pid)
 {
-    if (mutex->owner != pid) {
+    if (mutex->owner != pid || !atomic_load(&mutex->lk)) {
+        return;
+    }
+    __mutext_unlock(mutex);
+}
+
+void
+mutex_lock_nested(mutex_t* mutex)
+{
+    if (atomic_load(&mutex->lk) && __mutex_check_owner(mutex)) {
+        atomic_fetch_add(&mutex->lk, 1);
         return;
     }
-    sem_post(&mutex->sem);
+
+    __mutext_lock(mutex);
+}
+
+void
+mutex_unlock_nested(mutex_t* mutex)
+{
+    mutex_unlock_for(mutex, __current->pid);
 }
\ No newline at end of file