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| //===-- profile_collector_test.cpp ----------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of XRay, a function call tracing system.
//
//===----------------------------------------------------------------------===//
#include "gtest/gtest.h"
#include "xray_profile_collector.h"
#include "xray_profiling_flags.h"
#include <cstdint>
#include <cstring>
#include <memory>
#include <thread>
#include <utility>
#include <vector>
namespace __xray {
namespace {
static constexpr auto kHeaderSize = 16u;
constexpr uptr ExpectedProfilingVersion = 0x20180424;
struct ExpectedProfilingFileHeader {
const u64 MagicBytes = 0x7872617970726f66; // Identifier for XRay profiling
// files 'xrayprof' in hex.
const u64 Version = ExpectedProfilingVersion;
u64 Timestamp = 0;
u64 PID = 0;
};
void ValidateFileHeaderBlock(XRayBuffer B) {
ASSERT_NE(static_cast<const void *>(B.Data), nullptr);
ASSERT_EQ(B.Size, sizeof(ExpectedProfilingFileHeader));
typename std::aligned_storage<sizeof(ExpectedProfilingFileHeader)>::type
FileHeaderStorage;
ExpectedProfilingFileHeader ExpectedHeader;
std::memcpy(&FileHeaderStorage, B.Data, B.Size);
auto &FileHeader =
*reinterpret_cast<ExpectedProfilingFileHeader *>(&FileHeaderStorage);
ASSERT_EQ(ExpectedHeader.MagicBytes, FileHeader.MagicBytes);
ASSERT_EQ(ExpectedHeader.Version, FileHeader.Version);
}
void ValidateBlock(XRayBuffer B) {
profilingFlags()->setDefaults();
ASSERT_NE(static_cast<const void *>(B.Data), nullptr);
ASSERT_NE(B.Size, 0u);
ASSERT_GE(B.Size, kHeaderSize);
// We look at the block size, the block number, and the thread ID to ensure
// that none of them are zero (or that the header data is laid out as we
// expect).
char LocalBuffer[kHeaderSize] = {};
internal_memcpy(LocalBuffer, B.Data, kHeaderSize);
u32 BlockSize = 0;
u32 BlockNumber = 0;
u64 ThreadId = 0;
internal_memcpy(&BlockSize, LocalBuffer, sizeof(u32));
internal_memcpy(&BlockNumber, LocalBuffer + sizeof(u32), sizeof(u32));
internal_memcpy(&ThreadId, LocalBuffer + (2 * sizeof(u32)), sizeof(u64));
ASSERT_NE(BlockSize, 0u);
ASSERT_GE(BlockNumber, 0u);
ASSERT_NE(ThreadId, 0u);
}
std::tuple<u32, u32, u64> ParseBlockHeader(XRayBuffer B) {
char LocalBuffer[kHeaderSize] = {};
internal_memcpy(LocalBuffer, B.Data, kHeaderSize);
u32 BlockSize = 0;
u32 BlockNumber = 0;
u64 ThreadId = 0;
internal_memcpy(&BlockSize, LocalBuffer, sizeof(u32));
internal_memcpy(&BlockNumber, LocalBuffer + sizeof(u32), sizeof(u32));
internal_memcpy(&ThreadId, LocalBuffer + (2 * sizeof(u32)), sizeof(u64));
return std::make_tuple(BlockSize, BlockNumber, ThreadId);
}
struct Profile {
int64_t CallCount;
int64_t CumulativeLocalTime;
std::vector<int32_t> Path;
};
std::tuple<Profile, const char *> ParseProfile(const char *P) {
Profile Result;
// Read the path first, until we find a sentinel 0.
int32_t F;
do {
internal_memcpy(&F, P, sizeof(int32_t));
P += sizeof(int32_t);
Result.Path.push_back(F);
} while (F != 0);
// Then read the CallCount.
internal_memcpy(&Result.CallCount, P, sizeof(int64_t));
P += sizeof(int64_t);
// Then read the CumulativeLocalTime.
internal_memcpy(&Result.CumulativeLocalTime, P, sizeof(int64_t));
P += sizeof(int64_t);
return std::make_tuple(std::move(Result), P);
}
TEST(profileCollectorServiceTest, PostSerializeCollect) {
profilingFlags()->setDefaults();
bool Success = false;
BufferQueue BQ(profilingFlags()->per_thread_allocator_max,
profilingFlags()->buffers_max, Success);
ASSERT_EQ(Success, true);
FunctionCallTrie::Allocators::Buffers Buffers;
ASSERT_EQ(BQ.getBuffer(Buffers.NodeBuffer), BufferQueue::ErrorCode::Ok);
ASSERT_EQ(BQ.getBuffer(Buffers.RootsBuffer), BufferQueue::ErrorCode::Ok);
ASSERT_EQ(BQ.getBuffer(Buffers.ShadowStackBuffer),
BufferQueue::ErrorCode::Ok);
ASSERT_EQ(BQ.getBuffer(Buffers.NodeIdPairBuffer), BufferQueue::ErrorCode::Ok);
auto Allocators = FunctionCallTrie::InitAllocatorsFromBuffers(Buffers);
FunctionCallTrie T(Allocators);
// Populate the trie with some data.
T.enterFunction(1, 1, 0);
T.enterFunction(2, 2, 0);
T.exitFunction(2, 3, 0);
T.exitFunction(1, 4, 0);
// Reset the collector data structures.
profileCollectorService::reset();
// Then we post the data to the global profile collector service.
profileCollectorService::post(&BQ, std::move(T), std::move(Allocators),
std::move(Buffers), 1);
// Then we serialize the data.
profileCollectorService::serialize();
// Then we go through two buffers to see whether we're getting the data we
// expect. The first block must always be as large as a file header, which
// will have a fixed size.
auto B = profileCollectorService::nextBuffer({nullptr, 0});
ValidateFileHeaderBlock(B);
B = profileCollectorService::nextBuffer(B);
ValidateBlock(B);
u32 BlockSize;
u32 BlockNum;
u64 ThreadId;
std::tie(BlockSize, BlockNum, ThreadId) = ParseBlockHeader(B);
// We look at the serialized buffer to see whether the Trie we're expecting
// to see is there.
auto DStart = static_cast<const char *>(B.Data) + kHeaderSize;
std::vector<char> D(DStart, DStart + BlockSize);
B = profileCollectorService::nextBuffer(B);
ASSERT_EQ(B.Data, nullptr);
ASSERT_EQ(B.Size, 0u);
Profile Profile1, Profile2;
auto P = static_cast<const char *>(D.data());
std::tie(Profile1, P) = ParseProfile(P);
std::tie(Profile2, P) = ParseProfile(P);
ASSERT_NE(Profile1.Path.size(), Profile2.Path.size());
auto &P1 = Profile1.Path.size() < Profile2.Path.size() ? Profile2 : Profile1;
auto &P2 = Profile1.Path.size() < Profile2.Path.size() ? Profile1 : Profile2;
std::vector<int32_t> P1Expected = {2, 1, 0};
std::vector<int32_t> P2Expected = {1, 0};
ASSERT_EQ(P1.Path.size(), P1Expected.size());
ASSERT_EQ(P2.Path.size(), P2Expected.size());
ASSERT_EQ(P1.Path, P1Expected);
ASSERT_EQ(P2.Path, P2Expected);
}
// We break out a function that will be run in multiple threads, one that will
// use a thread local allocator, and will post the FunctionCallTrie to the
// profileCollectorService. This simulates what the threads being profiled would
// be doing anyway, but through the XRay logging implementation.
void threadProcessing() {
static bool Success = false;
static BufferQueue BQ(profilingFlags()->per_thread_allocator_max,
profilingFlags()->buffers_max, Success);
thread_local FunctionCallTrie::Allocators::Buffers Buffers = [] {
FunctionCallTrie::Allocators::Buffers B;
BQ.getBuffer(B.NodeBuffer);
BQ.getBuffer(B.RootsBuffer);
BQ.getBuffer(B.ShadowStackBuffer);
BQ.getBuffer(B.NodeIdPairBuffer);
return B;
}();
thread_local auto Allocators =
FunctionCallTrie::InitAllocatorsFromBuffers(Buffers);
FunctionCallTrie T(Allocators);
T.enterFunction(1, 1, 0);
T.enterFunction(2, 2, 0);
T.exitFunction(2, 3, 0);
T.exitFunction(1, 4, 0);
profileCollectorService::post(&BQ, std::move(T), std::move(Allocators),
std::move(Buffers), GetTid());
}
TEST(profileCollectorServiceTest, PostSerializeCollectMultipleThread) {
profilingFlags()->setDefaults();
profileCollectorService::reset();
std::thread t1(threadProcessing);
std::thread t2(threadProcessing);
t1.join();
t2.join();
// At this point, t1 and t2 are already done with what they were doing.
profileCollectorService::serialize();
// Ensure that we see two buffers.
auto B = profileCollectorService::nextBuffer({nullptr, 0});
ValidateFileHeaderBlock(B);
B = profileCollectorService::nextBuffer(B);
ValidateBlock(B);
B = profileCollectorService::nextBuffer(B);
ValidateBlock(B);
}
} // namespace
} // namespace __xray
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