From 32f7241526ea08b01a65290d9f84b8fc89f0241b Mon Sep 17 00:00:00 2001
From: disjtqz <chss95cs@gmail.com>
Date: Mon, 9 Oct 2023 16:04:51 -0400
Subject: [PATCH] fix user apc/kernel apc mixup

---
 .../kernel/xboxkrnl/xboxkrnl_threading.cc     |  9 ++----
 src/xenia/kernel/xthread.cc                   | 30 ++++++++++---------
 src/xenia/kernel/xthread.h                    |  2 +-
 3 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/src/xenia/kernel/xboxkrnl/xboxkrnl_threading.cc b/src/xenia/kernel/xboxkrnl/xboxkrnl_threading.cc
index df513bb6a..e826f2598 100644
--- a/src/xenia/kernel/xboxkrnl/xboxkrnl_threading.cc
+++ b/src/xenia/kernel/xboxkrnl/xboxkrnl_threading.cc
@@ -1178,12 +1178,9 @@ void KfLowerIrql_entry(dword_t new_irql, const ppc_context_t& ctx) {
   }
   kpcr->current_irql = new_irql;
   if (new_irql < 2) {
-    {
-      // this actually calls a function that eventually calls checkapcs.
-      // the called function does a ton of other stuff including changing the
-      // irql and interrupt_related
-      ctx.CurrentXThread()->CheckApcs();
-    }
+    // this actually calls a function that eventually calls checkapcs.
+    // the called function does a ton of other stuff including changing the
+    // irql and interrupt_related 
   }
 }
 DECLARE_XBOXKRNL_EXPORT2(KfLowerIrql, kThreading, kImplemented, kHighFrequency);
diff --git a/src/xenia/kernel/xthread.cc b/src/xenia/kernel/xthread.cc
index 0afbaa8ba..5f6c2d2a0 100644
--- a/src/xenia/kernel/xthread.cc
+++ b/src/xenia/kernel/xthread.cc
@@ -33,7 +33,6 @@ DEFINE_bool(ignore_thread_priorities, true,
 DEFINE_bool(ignore_thread_affinities, true,
             "Ignores game-specified thread affinities.", "Kernel");
 
-
 #if 0
 DEFINE_int64(stack_size_multiplier_hack, 1,
              "A hack for games with setjmp/longjmp issues.", "Kernel");
@@ -41,7 +40,7 @@ DEFINE_int64(main_xthread_stack_size_multiplier_hack, 1,
              "A hack for games with setjmp/longjmp issues.", "Kernel");
 #endif
 namespace xe {
-  namespace kernel {
+namespace kernel {
 
 const uint32_t XAPC::kSize;
 const uint32_t XAPC::kDummyKernelRoutine;
@@ -377,22 +376,20 @@ X_STATUS XThread::Create() {
   RetainHandle();
 
   xe::threading::Thread::CreationParameters params;
-  
-
 
   params.create_suspended = true;
 
-  #if 0
+#if 0
   uint64_t stack_size_mult = cvars::stack_size_multiplier_hack;
   
   if (main_thread_) {
     stack_size_mult =
         static_cast<uint64_t>(cvars::main_xthread_stack_size_multiplier_hack);
 
-  } 
-  #else
+  }
+#else
   uint64_t stack_size_mult = 1;
-  #endif
+#endif
   params.stack_size = 16_MiB * stack_size_mult;  // Allocate a big host stack.
   thread_ = xe::threading::Thread::Create(params, [this]() {
     // Set thread ID override. This is used by logging.
@@ -454,7 +451,6 @@ X_STATUS XThread::Exit(int exit_code) {
   assert_true(XThread::GetCurrentThread() == this);
   //TODO(chrispy): not sure if this order is correct, should it come after apcs?
   guest_object<X_KTHREAD>()->terminated = 1;
- 
 
   // TODO(benvanik): dispatch events? waiters? etc?
   RundownAPCs();
@@ -590,10 +586,8 @@ void XThread::EnterCriticalRegion() {
 
 void XThread::LeaveCriticalRegion() {
   auto kthread = guest_object<X_KTHREAD>();
+  // this has nothing to do with user mode apcs!
   auto apc_disable_count = ++kthread->apc_disable_count;
-  if (apc_disable_count == 0) {
-    CheckApcs();
-  }
 }
 
 uint32_t XThread::RaiseIrql(uint32_t new_irql) {
@@ -610,7 +604,13 @@ void XThread::UnlockApc(bool queue_delivery) {
   bool needs_apc = apc_list_.HasPending();
   global_critical_region_.mutex().unlock();
   if (needs_apc && queue_delivery) {
-    thread_->QueueUserCallback([this]() { DeliverAPCs(); });
+    thread_->QueueUserCallback([this]() {
+      cpu::ThreadState::Bind(this->thread_state());
+      this->SetCurrentThread();  // we store current thread in TLS, but tls
+                                 // slots are different in windows user
+                                 // callback!
+      DeliverAPCs();
+    });
   }
 }
 
@@ -638,6 +638,8 @@ void XThread::EnqueueApc(uint32_t normal_routine, uint32_t normal_context,
   UnlockApc(true);
 }
 
+void XThread::SetCurrentThread() { current_xthread_tls_ = this; }
+
 void XThread::DeliverAPCs() {
   // https://www.drdobbs.com/inside-nts-asynchronous-procedure-call/184416590?pgno=1
   // https://www.drdobbs.com/inside-nts-asynchronous-procedure-call/184416590?pgno=7
@@ -789,7 +791,7 @@ void XThread::SetActiveCpu(uint8_t cpu_index) {
     }
   } else {
 	  //there no good reason why we need to log this... we don't perfectly emulate the 360's scheduler in any way
-   // XELOGW("Too few processor cores - scheduling will be wonky");
+    // XELOGW("Too few processor cores - scheduling will be wonky");
   }
 }
 
diff --git a/src/xenia/kernel/xthread.h b/src/xenia/kernel/xthread.h
index f5bac2942..74139e679 100644
--- a/src/xenia/kernel/xthread.h
+++ b/src/xenia/kernel/xthread.h
@@ -259,7 +259,7 @@ class XThread : public XObject, public cpu::Thread {
   void AcquireMutantOnStartup(object_ref<XMutant> mutant) {
     pending_mutant_acquires_.push_back(mutant);
   }
-
+  void SetCurrentThread();
  protected:
   bool AllocateStack(uint32_t size);
   void FreeStack();