Mirrors/yuzu
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Kernel: Implemented mutex priority inheritance.

Browse source 
Verified with a hwtest and implemented based on reverse engineering.

Thread A's priority will get bumped to the highest priority among all the threads that are waiting for a mutex that A holds.
Once A releases the mutex and ownership is transferred to B, A's priority will return to normal and B's priority will be bumped.
This commit is contained in:
Subv 2018-04-20 20:15:16 -05:00
parent a70ed9c8ae
commit 46572d027d
4 changed files with 94 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

41
src/core/hle/kernel/thread.cpp
View file

@ -129,6 +129,11 @@ static void ThreadWakeupCallback(u64 thread_handle, int cycles_late) {
thread->mutex_wait_address = 0;
thread->condvar_wait_address = 0;
thread->wait_handle = 0;
auto lock_owner = thread->lock_owner;
// Threads waking up by timeout from WaitProcessWideKey do not perform priority inheritance
// and don't have a lock owner.
ASSERT(lock_owner == nullptr);
}
if (resume)
@ -325,8 +330,8 @@ ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point,
void Thread::SetPriority(u32 priority) {
ASSERT_MSG(priority <= THREADPRIO_LOWEST && priority >= THREADPRIO_HIGHEST,
"Invalid priority value.");
Core::System::GetInstance().Scheduler().SetThreadPriority(this, priority);
nominal_priority = current_priority = priority;
nominal_priority = priority;
UpdatePriority();
}
void Thread::BoostPriority(u32 priority) {
@ -376,6 +381,38 @@ VAddr Thread::GetCommandBufferAddress() const {
return GetTLSAddress() + CommandHeaderOffset;
}
void Thread::AddMutexWaiter(SharedPtr<Thread> thread) {
thread->lock_owner = this;
wait_mutex_threads.emplace_back(std::move(thread));
UpdatePriority();
}
void Thread::RemoveMutexWaiter(SharedPtr<Thread> thread) {
boost::remove_erase(wait_mutex_threads, thread);
thread->lock_owner = nullptr;
UpdatePriority();
}
void Thread::UpdatePriority() {
// Find the highest priority among all the threads that are waiting for this thread's lock
u32 new_priority = nominal_priority;
for (const auto& thread : wait_mutex_threads) {
if (thread->nominal_priority < new_priority)
new_priority = thread->nominal_priority;
}
if (new_priority == current_priority)
return;
Core::System::GetInstance().Scheduler().SetThreadPriority(this, new_priority);
current_priority = new_priority;
// Recursively update the priority of the thread that depends on the priority of this one.
if (lock_owner)
lock_owner->UpdatePriority();
}
////////////////////////////////////////////////////////////////////////////////////////////////////
/**