Revert "Reland [wasm] Reduce job priority once baseline compilation finishes"

This reverts commit 83d289b8.

Reason for revert: lock order inversion, see https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux64%20TSAN%20-%20isolates/12584/overview

Original change's description:
> Reland [wasm] Reduce job priority once baseline compilation finishes
>
> ReduceCompilationPriority takes a lock now.
>
> Original message:
> This Cl changes the priority of baseline compilation from kUserVisible
> to kUserBlocking. Once baseline compilation finishes, the priority is
> reduced to kUserVisible. The reason for using kUserBlocking is that
> thereby TurboFan compilation cannot block Liftoff compilation anymore.
> Additionally, kUserBlocking is quite appropriate, as the initial
> compilation does block a whole section of a web app from execution.
>
> R=​clemensb@chromium.org
>
> Bug: v8:11088
> Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
> Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_isolates_rel_ng
> Change-Id: I6e1bcc809148198a4b4f88bfd4f2e62b1b061439
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2563675
> Commit-Queue: Andreas Haas <ahaas@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#71546}

TBR=ahaas@chromium.org,clemensb@chromium.org

Change-Id: I62e4e3d0663dbd181b14f77f0c1586d5e503f324
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:11088
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_isolates_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2567953Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71557}

src/wasm/module-compiler.cc

@@ -595,11 +595,9 @@ class CompilationStateImpl {
 
   void WaitForCompilationEvent(CompilationEvent event);
 
-  void ReduceCompilationPriority() {
+  void SetHighPriority() {
     base::MutexGuard guard(&mutex_);
-    if (current_compile_job_ && current_compile_job_->UpdatePriorityEnabled()) {
-      current_compile_job_->UpdatePriority(TaskPriority::kUserVisible);
-    }
+    has_priority_ = true;
   }
 
   bool failed() const {
@@ -677,6 +675,8 @@ class CompilationStateImpl {
   //////////////////////////////////////////////////////////////////////////////
   // Protected by {mutex_}:
 
+  bool has_priority_ = false;
+
   std::shared_ptr<JobHandle> current_compile_job_;
 
   // Features detected to be used in this module. Features can be detected
@@ -799,6 +799,8 @@ void CompilationState::WaitForTopTierFinished() {
   top_tier_finished_semaphore->Wait();
 }
 
+void CompilationState::SetHighPriority() { Impl(this)->SetHighPriority(); }
+
 void CompilationState::InitializeAfterDeserialization() {
   Impl(this)->InitializeCompilationProgressAfterDeserialization();
 }
@@ -1636,6 +1638,8 @@ std::shared_ptr<NativeModule> CompileToNativeModule(
   native_module = isolate->wasm_engine()->NewNativeModule(
       isolate, enabled, module, code_size_estimate);
   native_module->SetWireBytes(std::move(wire_bytes_copy));
+  // Sync compilation is user blocking, so we increase the priority.
+  native_module->compilation_state()->SetHighPriority();
 
   v8::metrics::Recorder::ContextId context_id =
       isolate->GetOrRegisterRecorderContextId(isolate->native_context());
@@ -2717,13 +2721,7 @@ CompilationStateImpl::CompilationStateImpl(
                         ? CompileMode::kTiering
                         : CompileMode::kRegular),
       async_counters_(std::move(async_counters)),
-      compilation_unit_queues_(native_module->num_functions()) {
-  AddCallback([&](CompilationEvent event) {
-    if (event == CompilationEvent::kFinishedBaselineCompilation) {
-      ReduceCompilationPriority();
-    }
-  });
-}
+      compilation_unit_queues_(native_module->num_functions()) {}
 
 void CompilationStateImpl::CancelCompilation() {
   // No more callbacks after abort.
@@ -3247,8 +3245,13 @@ void CompilationStateImpl::ScheduleCompileJobForNewUnits() {
                                                async_counters_);
     // TODO(wasm): Lower priority for TurboFan-only jobs.
     new_job_handle = V8::GetCurrentPlatform()->PostJob(
-        TaskPriority::kUserBlocking, std::move(new_compile_job));
+        has_priority_ ? TaskPriority::kUserBlocking
+                      : TaskPriority::kUserVisible,
+        std::move(new_compile_job));
     current_compile_job_ = new_job_handle;
+    // Reset the priority. Later uses of the compilation state, e.g. for
+    // debugging, should compile with the default priority again.
+    has_priority_ = false;
   }
 
   if (new_job_handle) {
@@ -3371,7 +3374,7 @@ void CompileJsToWasmWrappers(Isolate* isolate, const WasmModule* module,
   auto job = std::make_unique<CompileJSToWasmWrapperJob>(
       &queue, &compilation_units, max_concurrency);
   auto job_handle = V8::GetCurrentPlatform()->PostJob(
-      TaskPriority::kUserBlocking, std::move(job));
+      TaskPriority::kUserVisible, std::move(job));
 
   // Wait for completion, while contributing to the work.
   job_handle->Join();