From 1f286b72a1b9e1fb98e37a01192f4e31b0ad4e1f Mon Sep 17 00:00:00 2001
From: Subv <subv2112@gmail.com>
Date: Tue, 6 Dec 2016 19:15:32 -0500
Subject: [PATCH] Improved the algorithm for GetHighestPriorityReadyThread.
---
src/core/hle/kernel/kernel.cpp | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)
diff --git a/src/core/hle/kernel/kernel.cpp b/src/core/hle/kernel/kernel.cpp
index 6d358def78..07f4200993 100644
--- a/src/core/hle/kernel/kernel.cpp
+++ b/src/core/hle/kernel/kernel.cpp
@@ -40,24 +40,23 @@ SharedPtr<Thread> WaitObject::GetHighestPriorityReadyThread() {
if (waiting_threads.empty())
return nullptr;
- auto candidate_threads = waiting_threads;
+ SharedPtr<Thread> candidate = nullptr;
+ s32 candidate_priority = THREADPRIO_LOWEST + 1;
- // Eliminate all threads that are waiting on more than one object, and not all of said objects are ready
- candidate_threads.erase(std::remove_if(candidate_threads.begin(), candidate_threads.end(), [](const SharedPtr<Thread>& thread) -> bool {
- return std::any_of(thread->wait_objects.begin(), thread->wait_objects.end(), [](const SharedPtr<WaitObject>& object) -> bool {
+ for (const auto& thread : waiting_threads) {
+ if (thread->current_priority >= candidate_priority)
+ continue;
+
+ bool ready_to_run = std::none_of(thread->wait_objects.begin(), thread->wait_objects.end(), [](const SharedPtr<WaitObject>& object) {
return object->ShouldWait();
});
- }), candidate_threads.end());
+ if (ready_to_run) {
+ candidate = thread;
+ candidate_priority = thread->current_priority;
+ }
+ }
- // Return the thread with the lowest priority value (The one with the highest priority)
- auto thread_itr = std::min_element(candidate_threads.begin(), candidate_threads.end(), [](const SharedPtr<Thread>& lhs, const SharedPtr<Thread>& rhs) {
- return lhs->current_priority < rhs->current_priority;
- });
-
- if (thread_itr == candidate_threads.end())
- return nullptr;
-
- return *thread_itr;
+ return candidate;
}
void WaitObject::WakeupAllWaitingThreads() {