blob: 8d52daa949d44ace0d6f187e893209591363b40c [file] [log] [blame]
// Copyright (c) 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/pending_task.h"
#include <vector>
#include "base/bind.h"
#include "base/message_loop/message_loop.h"
#include "base/run_loop.h"
#include "base/strings/stringprintf.h"
#include "base/threading/thread.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace base {
class PendingTaskTest : public ::testing::Test {
public:
PendingTaskTest() = default;
~PendingTaskTest() override = default;
protected:
using ExpectedTrace = std::vector<const void*>;
static void VerifyTraceAndPost(
const scoped_refptr<TaskRunner>& task_runner,
const tracked_objects::Location& posted_from,
const tracked_objects::Location& next_from_here,
const std::vector<const void*>& expected_trace,
Closure task) {
SCOPED_TRACE(StringPrintf("Callback Depth: %zu", expected_trace.size()));
// Beyond depth + 1, the trace is nonsensical because there haven't been
// enough nested tasks called.
const PendingTask* current_pending_task =
MessageLoop::current()->current_pending_task_;
size_t window = std::min(current_pending_task->task_backtrace.size(),
expected_trace.size());
EXPECT_EQ(posted_from,
MessageLoop::current()->current_pending_task_->posted_from);
for (size_t i = 0; i < window; i++) {
SCOPED_TRACE(StringPrintf("Trace frame: %zu", i));
EXPECT_EQ(expected_trace[i], current_pending_task->task_backtrace[i]);
}
task_runner->PostTask(next_from_here, std::move(task));
}
static void RunTwo(Closure c1, Closure c2) {
c1.Run();
c2.Run();
}
};
// Ensure the task backtrace populates correctly.
TEST_F(PendingTaskTest, SingleThreadedSimple) {
MessageLoop loop;
const tracked_objects::Location& location0 = FROM_HERE;
const tracked_objects::Location& location1 = FROM_HERE;
const tracked_objects::Location& location2 = FROM_HERE;
const tracked_objects::Location& location3 = FROM_HERE;
const tracked_objects::Location& location4 = FROM_HERE;
const tracked_objects::Location& location5 = FROM_HERE;
Closure task5 = Bind(
&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(), location4,
location5,
ExpectedTrace({location3.program_counter(), location2.program_counter(),
location1.program_counter(), location0.program_counter()}),
Bind(&DoNothing));
Closure task4 = Bind(
&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(), location3,
location4,
ExpectedTrace({location2.program_counter(), location1.program_counter(),
location0.program_counter(), nullptr}),
task5);
Closure task3 = Bind(
&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(), location2,
location3, ExpectedTrace({location1.program_counter(),
location0.program_counter(), nullptr, nullptr}),
task4);
Closure task2 =
Bind(&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(), location1,
location2, ExpectedTrace({location0.program_counter()}), task3);
Closure task1 = Bind(&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(),
location0, location1, ExpectedTrace({}), task2);
loop.task_runner()->PostTask(location0, task1);
RunLoop().RunUntilIdle();
}
// Post a task onto another thread. Ensure on the other thread, it has the
// right stack trace.
TEST_F(PendingTaskTest, MultipleThreads) {
MessageLoop loop; // Implicitly "thread a."
Thread thread_b("pt_test_b");
Thread thread_c("pt_test_c");
thread_b.StartAndWaitForTesting();
thread_c.StartAndWaitForTesting();
const tracked_objects::Location& location_a0 = FROM_HERE;
const tracked_objects::Location& location_a1 = FROM_HERE;
const tracked_objects::Location& location_a2 = FROM_HERE;
const tracked_objects::Location& location_a3 = FROM_HERE;
const tracked_objects::Location& location_b0 = FROM_HERE;
const tracked_objects::Location& location_b1 = FROM_HERE;
const tracked_objects::Location& location_c0 = FROM_HERE;
// On thread c, post a task back to thread a that verifies its trace
// and terminates after one more self-post.
Closure task_a2 =
Bind(&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(),
location_a2, location_a3,
ExpectedTrace(
{location_c0.program_counter(), location_b0.program_counter(),
location_a1.program_counter(), location_a0.program_counter()}),
Bind(&DoNothing));
Closure task_c0 = Bind(&PendingTaskTest::VerifyTraceAndPost,
loop.task_runner(), location_c0, location_a2,
ExpectedTrace({location_b0.program_counter(),
location_a1.program_counter(),
location_a0.program_counter()}),
task_a2);
// On thread b run two tasks that conceptually come from the same location
// (managed via RunTwo().) One will post back to thread b and another will
// post to thread c to test spawning multiple tasks on different message
// loops. The task posted to thread c will not get location b1 whereas the
// one posted back to thread b will.
Closure task_b0_fork =
Bind(&PendingTaskTest::VerifyTraceAndPost,
thread_c.message_loop()->task_runner(), location_b0, location_c0,
ExpectedTrace({location_a1.program_counter(),
location_a0.program_counter(), nullptr}),
task_c0);
Closure task_b0_local =
Bind(&PendingTaskTest::VerifyTraceAndPost,
thread_b.message_loop()->task_runner(), location_b0, location_b1,
ExpectedTrace({location_a1.program_counter(),
location_a0.program_counter(), nullptr}),
Bind(&DoNothing));
// Push one frame onto the stack in thread a then pass to thread b.
Closure task_a1 =
Bind(&PendingTaskTest::VerifyTraceAndPost,
thread_b.message_loop()->task_runner(), location_a1, location_b0,
ExpectedTrace({location_a0.program_counter(), nullptr}),
Bind(&PendingTaskTest::RunTwo, task_b0_local, task_b0_fork));
Closure task_a0 =
Bind(&PendingTaskTest::VerifyTraceAndPost, loop.task_runner(),
location_a0, location_a1, ExpectedTrace({nullptr}), task_a1);
loop.task_runner()->PostTask(location_a0, task_a0);
RunLoop().RunUntilIdle();
thread_b.FlushForTesting();
thread_b.Stop();
thread_c.FlushForTesting();
thread_c.Stop();
}
} // namespace base