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/* -*- 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/IntegerRange.h"
#include "js/Vector.h"
#include "jsapi-tests/tests.h"
#include "threading/ExclusiveData.h"
#include "threading/Thread.h"
// One thread for each bit in our counter.
const static uint8_t NumThreads = 64;
const static bool ShowDiagnostics = false;
struct CounterAndBit {
uint8_t bit;
const js::ExclusiveData<uint64_t>& counter;
CounterAndBit(uint8_t bit, const js::ExclusiveData<uint64_t>& counter)
: bit(bit), counter(counter) {
MOZ_ASSERT(bit < NumThreads);
}
};
void printDiagnosticMessage(uint8_t bit, uint64_t seen) {
if (!ShowDiagnostics) {
return;
}
fprintf(stderr, "Thread %d saw ", bit);
for (auto i : mozilla::IntegerRange(NumThreads)) {
if (seen & (uint64_t(1) << i)) {
fprintf(stderr, "1");
} else {
fprintf(stderr, "0");
}
}
fprintf(stderr, "\n");
}
void setBitAndCheck(CounterAndBit* counterAndBit) {
while (true) {
{
// Set our bit. Repeatedly setting it is idempotent.
auto guard = counterAndBit->counter.lock();
printDiagnosticMessage(counterAndBit->bit, guard);
guard |= (uint64_t(1) << counterAndBit->bit);
}
{
// Check to see if we have observed all the other threads setting
// their bit as well.
auto guard = counterAndBit->counter.lock();
printDiagnosticMessage(counterAndBit->bit, guard);
if (guard == UINT64_MAX) {
js_delete(counterAndBit);
return;
}
}
}
}
BEGIN_TEST(testExclusiveData) {
js::ExclusiveData<uint64_t> counter(js::mutexid::TestMutex, 0);
js::Vector<js::Thread> threads(cx);
CHECK(threads.reserve(NumThreads));
for (auto i : mozilla::IntegerRange(NumThreads)) {
auto counterAndBit = js_new<CounterAndBit>(i, counter);
CHECK(counterAndBit);
CHECK(threads.emplaceBack());
CHECK(threads.back().init(setBitAndCheck, counterAndBit));
}
for (auto& thread : threads) {
thread.join();
}
return true;
}
END_TEST(testExclusiveData)