blob: d0220263425ab9916ad12f7d0c90bf4d0340fa04 [file] [log] [blame]
// Copyright (c) 2012 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/logging.h"
#include "base/test/test_timeouts.h"
#include "base/win/sampling_profiler.h"
#include "base/win/pe_image.h"
#include "base/win/scoped_handle.h"
#include "base/win/windows_version.h"
#include "testing/gtest/include/gtest/gtest.h"
// The address of our image base.
extern "C" IMAGE_DOS_HEADER __ImageBase;
namespace base {
namespace win {
namespace {
class SamplingProfilerTest : public testing::Test {
public:
SamplingProfilerTest() : code_start(NULL), code_size(0) {
}
virtual void SetUp() {
process.Set(::OpenProcess(PROCESS_QUERY_INFORMATION,
FALSE,
::GetCurrentProcessId()));
ASSERT_TRUE(process.IsValid());
PEImage image(&__ImageBase);
// Get the address of the .text section, which is the first section output
// by the VS tools.
ASSERT_TRUE(image.GetNumSections() > 0);
const IMAGE_SECTION_HEADER* text_section = image.GetSectionHeader(0);
ASSERT_EQ(0, strncmp(".text",
reinterpret_cast<const char*>(text_section->Name),
arraysize(text_section->Name)));
ASSERT_NE(0U, text_section->Characteristics & IMAGE_SCN_MEM_EXECUTE);
code_start = reinterpret_cast<uint8*>(&__ImageBase) +
text_section->VirtualAddress;
code_size = text_section->Misc.VirtualSize;
}
protected:
ScopedHandle process;
void* code_start;
size_t code_size;
};
} // namespace
TEST_F(SamplingProfilerTest, Initialize) {
SamplingProfiler profiler;
ASSERT_TRUE(profiler.Initialize(process.Get(), code_start, code_size, 8));
}
TEST_F(SamplingProfilerTest, Sample) {
if (base::win::GetVersion() == base::win::VERSION_WIN8) {
LOG(INFO) << "Not running test on Windows 8";
return;
}
SamplingProfiler profiler;
// Initialize with a huge bucket size, aiming for a single bucket.
ASSERT_TRUE(
profiler.Initialize(process.Get(), code_start, code_size, 31));
ASSERT_EQ(1, profiler.buckets().size());
ASSERT_EQ(0, profiler.buckets()[0]);
// We use a roomy timeout to make sure this test is not flaky.
// On the buildbots, there may not be a whole lot of CPU time
// allotted to our process in this wall-clock time duration,
// and samples will only accrue while this thread is busy on
// a CPU core.
base::TimeDelta spin_time = TestTimeouts::action_timeout();
base::TimeDelta save_sampling_interval;
ASSERT_TRUE(SamplingProfiler::GetSamplingInterval(&save_sampling_interval));
// Sample every 0.5 millisecs.
ASSERT_TRUE(SamplingProfiler::SetSamplingInterval(
base::TimeDelta::FromMicroseconds(500)));
ASSERT_TRUE(SamplingProfiler::SetSamplingInterval(
base::TimeDelta::FromMicroseconds(500)));
// Start the profiler.
ASSERT_TRUE(profiler.Start());
// Get a volatile pointer to our bucket to make sure that the compiler
// doesn't optimize out the test in the loop that follows.
volatile const ULONG* bucket_ptr = &profiler.buckets()[0];
// Spin for spin_time wall-clock seconds, or until we get some samples.
// Note that sleeping isn't going to do us any good, the samples only
// accrue while we're executing code.
base::Time start = base::Time::Now();
base::TimeDelta elapsed;
do {
elapsed = base::Time::Now() - start;
} while((elapsed < spin_time) && *bucket_ptr == 0);
// Stop the profiler.
ASSERT_TRUE(profiler.Stop());
// Restore the sampling interval we found.
ASSERT_TRUE(SamplingProfiler::SetSamplingInterval(save_sampling_interval));
// Check that we got some samples.
ASSERT_NE(0U, profiler.buckets()[0]);
}
} // namespace win
} // namespace base