mirror of
https://github.com/RGBCube/serenity
synced 2025-07-25 19:37:35 +00:00
Kernel: Add a blunt big process lock.
We can't have multiple threads in the same process running in the kernel at the same time, so let's have a per-process lock that threads have to acquire on syscall entry/exit (and yield while blocked.)
This commit is contained in:
parent
54ea35703a
commit
d5a9f4596b
5 changed files with 37 additions and 0 deletions
|
@ -26,6 +26,7 @@ public:
|
|||
|
||||
void lock();
|
||||
void unlock();
|
||||
bool unlock_if_locked();
|
||||
|
||||
const char* name() const { return m_name; }
|
||||
|
||||
|
@ -90,6 +91,32 @@ inline void Lock::unlock()
|
|||
}
|
||||
}
|
||||
|
||||
inline bool Lock::unlock_if_locked()
|
||||
{
|
||||
for (;;) {
|
||||
if (CAS(&m_lock, 1, 0) == 0) {
|
||||
if (m_level == 0) {
|
||||
memory_barrier();
|
||||
m_lock = 0;
|
||||
return false;
|
||||
}
|
||||
ASSERT(m_holder == current);
|
||||
ASSERT(m_level);
|
||||
--m_level;
|
||||
if (m_level) {
|
||||
memory_barrier();
|
||||
m_lock = 0;
|
||||
return false;
|
||||
}
|
||||
m_holder = nullptr;
|
||||
memory_barrier();
|
||||
m_lock = 0;
|
||||
return true;
|
||||
}
|
||||
Scheduler::donate_to(m_holder, m_name);
|
||||
}
|
||||
}
|
||||
|
||||
#define LOCKER(lock) Locker locker(lock)
|
||||
|
||||
template<typename T>
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue