Is an inline function atomic?

Question

Can linux context switch after unlock in the below code if so we have a problem if two threads call this

inline bool CMyAutoLock::Lock(
    pthread_mutex_t *pLock,
    bool bBlockOk 
)
throw ()
{
    Unlock();
    if (pLock == NULL)
        return (false);
// **** can context switch happen here ? ****///
    return ((((bBlockOk)? pthread_mutex_lock(pLock) :
        pthread_mutex_trylock(pLock)) == 0)? (m_pLock = pLock, true) : false);
}

Answer 1

No, it's not atomic.

In fact, it may be especially likely for a context switch to occur after you've unlocked a mutex, because the OS knows if another thread is blocked on that mutex. (On the other hand, the OS doesn't even know whether you're executing an inline function.)