1 files changed, 169 insertions, 0 deletions
diff --git a/mfbt/tests/TestMPSCQueue.cpp b/mfbt/tests/TestMPSCQueue.cpp
new file mode 100644
index 0000000000..6ad668d115
--- /dev/null
+++ b/mfbt/tests/TestMPSCQueue.cpp
@@ -0,0 +1,169 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/MPSCQueue.h"
+#include "mozilla/PodOperations.h"
+#include <vector>
+#include <iostream>
+#include <thread>
+#include <chrono>
+#include <memory>
+#include <string>
+
+using namespace mozilla;
+
+struct NativeStack {
+  void* mPCs[32];
+  void* mSPs[32];
+  size_t mCount;
+  size_t mTid;
+};
+
+void StackWalkCallback(void* aPC, void* aSP, NativeStack* nativeStack) {
+  nativeStack->mSPs[nativeStack->mCount] = aSP;
+  nativeStack->mPCs[nativeStack->mCount] = aPC;
+  nativeStack->mCount++;
+}
+
+void FillNativeStack(NativeStack* aStack) {
+  StackWalkCallback((void*)0x1234, (void*)0x9876, aStack);
+  StackWalkCallback((void*)0x3456, (void*)0x5432, aStack);
+  StackWalkCallback((void*)0x7890, (void*)0x1098, aStack);
+  StackWalkCallback((void*)0x1234, (void*)0x7654, aStack);
+  StackWalkCallback((void*)0x5678, (void*)0x3210, aStack);
+  StackWalkCallback((void*)0x9012, (void*)0x9876, aStack);
+  StackWalkCallback((void*)0x1334, (void*)0x9786, aStack);
+  StackWalkCallback((void*)0x3546, (void*)0x5342, aStack);
+  StackWalkCallback((void*)0x7809, (void*)0x0198, aStack);
+  StackWalkCallback((void*)0x4123, (void*)0x7645, aStack);
+  StackWalkCallback((void*)0x5768, (void*)0x3120, aStack);
+  StackWalkCallback((void*)0x9102, (void*)0x9867, aStack);
+  StackWalkCallback((void*)0x1243, (void*)0x8976, aStack);
+  StackWalkCallback((void*)0x6345, (void*)0x4325, aStack);
+  StackWalkCallback((void*)0x8790, (void*)0x1908, aStack);
+  StackWalkCallback((void*)0x134, (void*)0x654, aStack);
+  StackWalkCallback((void*)0x567, (void*)0x320, aStack);
+  StackWalkCallback((void*)0x901, (void*)0x976, aStack);
+}
+
+void BasicAPITestWithStack(MPSCQueue<NativeStack>& aQueue, size_t aCap) {
+  MOZ_RELEASE_ASSERT(aQueue.Capacity() == aCap);
+
+  NativeStack s = {.mCount = 0};
+  FillNativeStack(&s);
+  MOZ_RELEASE_ASSERT(s.mCount == 18);
+
+  int store = -1;
+  for (size_t i = 0; i < aCap; ++i) {
+    store = aQueue.Send(s);
+    MOZ_RELEASE_ASSERT(store > 0);
+  }
+
+  int retrieve = -1;
+  for (size_t i = 0; i < aCap; ++i) {
+    NativeStack sr{};
+    retrieve = aQueue.Recv(&sr);
+
+    MOZ_RELEASE_ASSERT(retrieve > 0);
+    MOZ_RELEASE_ASSERT(&s != &sr);
+    MOZ_RELEASE_ASSERT(s.mCount == sr.mCount);
+
+    for (size_t i = 0; i < s.mCount; ++i) {
+      MOZ_RELEASE_ASSERT(s.mPCs[i] == sr.mPCs[i]);
+      MOZ_RELEASE_ASSERT(s.mSPs[i] == sr.mSPs[i]);
+    }
+  }
+}
+
+void BasicAPITestMP(MPSCQueue<NativeStack>& aQueue, size_t aThreads) {
+  MOZ_RELEASE_ASSERT(aQueue.Capacity() == 15);
+
+  std::thread consumer([&aQueue, aThreads] {
+    size_t received = 0;
+    NativeStack v{};
+    do {
+      int deq = aQueue.Recv(&v);
+      if (deq > 0) {
+        received++;
+      }
+      std::this_thread::sleep_for(std::chrono::microseconds(10));
+    } while (received < aThreads);
+  });
+
+  std::thread producers[aThreads];
+  for (size_t t = 0; t < aThreads; ++t) {
+    producers[t] = std::thread([&aQueue, t] {
+      NativeStack s = {.mCount = 0, .mTid = t};
+      FillNativeStack(&s);
+      MOZ_RELEASE_ASSERT(s.mCount == 18);
+
+      int sent = 0;
+      // wrap in a do { } while () because Send() will return 0 on message being
+      // dropped so we want to retry
+      do {
+        std::this_thread::sleep_for(std::chrono::microseconds(5));
+        sent = aQueue.Send(s);
+      } while (sent == 0);
+    });
+  }
+
+  for (size_t t = 0; t < aThreads; ++t) {
+    producers[t].join();
+  }
+  consumer.join();
+}
+
+int main() {
+  size_t caps[] = {2, 5, 7, 10, 15};
+  for (auto maxCap : caps) {
+    MPSCQueue<NativeStack> s(maxCap);
+    BasicAPITestWithStack(s, maxCap);
+  }
+
+  {
+    NativeStack e{};
+    MPSCQueue<NativeStack> deq(2);
+
+    // Dequeue with nothing should return 0 and not fail later
+    int retrieve = deq.Recv(&e);
+    MOZ_RELEASE_ASSERT(retrieve == 0);
+
+    NativeStack real = {.mCount = 0};
+    FillNativeStack(&real);
+    MOZ_RELEASE_ASSERT(real.mCount == 18);
+
+    int store = deq.Send(real);
+    MOZ_RELEASE_ASSERT(store > 0);
+    store = deq.Send(real);
+    MOZ_RELEASE_ASSERT(store > 0);
+
+    // should be full we should get 0
+    store = deq.Send(real);
+    MOZ_RELEASE_ASSERT(store == 0);
+
+    // try to dequeue
+    NativeStack e1{};
+    retrieve = deq.Recv(&e1);
+    MOZ_RELEASE_ASSERT(retrieve > 0);
+    MOZ_RELEASE_ASSERT(e1.mCount == 18);
+
+    NativeStack e2{};
+    retrieve = deq.Recv(&e2);
+    MOZ_RELEASE_ASSERT(retrieve > 0);
+    MOZ_RELEASE_ASSERT(e2.mCount == 18);
+
+    retrieve = deq.Recv(&e);
+    MOZ_RELEASE_ASSERT(retrieve == 0);
+  }
+
+  size_t nbThreads[] = {8, 16, 64, 128, 512, 1024};
+  for (auto threads : nbThreads) {
+    MPSCQueue<NativeStack> s(15);
+    BasicAPITestMP(s, threads);
+  }
+
+  return 0;
+}