diff options
Diffstat (limited to 'absl/flags/flag_test.cc')
| -rw-r--r-- | absl/flags/flag_test.cc | 55 |
1 files changed, 47 insertions, 8 deletions
diff --git a/absl/flags/flag_test.cc b/absl/flags/flag_test.cc index 654c8122..72507b99 100644 --- a/absl/flags/flag_test.cc +++ b/absl/flags/flag_test.cc @@ -18,6 +18,7 @@ #include <stddef.h> #include <stdint.h> +#include <atomic> #include <cmath> #include <new> #include <string> @@ -26,6 +27,7 @@ #include "gtest/gtest.h" #include "absl/base/attributes.h" +#include "absl/base/macros.h" #include "absl/flags/config.h" #include "absl/flags/declare.h" #include "absl/flags/internal/flag.h" @@ -108,16 +110,16 @@ TEST_F(FlagTest, Traits) { EXPECT_EQ(flags::StorageKind<int64_t>(), flags::FlagValueStorageKind::kOneWordAtomic); -#if defined(ABSL_FLAGS_INTERNAL_ATOMIC_DOUBLE_WORD) EXPECT_EQ(flags::StorageKind<S1>(), - flags::FlagValueStorageKind::kTwoWordsAtomic); + flags::FlagValueStorageKind::kSequenceLocked); EXPECT_EQ(flags::StorageKind<S2>(), - flags::FlagValueStorageKind::kTwoWordsAtomic); -#else - EXPECT_EQ(flags::StorageKind<S1>(), - flags::FlagValueStorageKind::kAlignedBuffer); - EXPECT_EQ(flags::StorageKind<S2>(), - flags::FlagValueStorageKind::kAlignedBuffer); + flags::FlagValueStorageKind::kSequenceLocked); +// Make sure absl::Duration uses the sequence-locked code path. MSVC 2015 +// doesn't consider absl::Duration to be trivially-copyable so we just +// restrict this to clang as it seems to be a well-behaved compiler. +#ifdef __clang__ + EXPECT_EQ(flags::StorageKind<absl::Duration>(), + flags::FlagValueStorageKind::kSequenceLocked); #endif EXPECT_EQ(flags::StorageKind<std::string>(), @@ -583,6 +585,43 @@ TEST_F(FlagTest, TestGetViaReflection) { // -------------------------------------------------------------------- +TEST_F(FlagTest, ConcurrentSetAndGet) { + static constexpr int kNumThreads = 8; + // Two arbitrary durations. One thread will concurrently flip the flag + // between these two values, while the other threads read it and verify + // that no other value is seen. + static const absl::Duration kValidDurations[] = { + absl::Seconds(int64_t{0x6cebf47a9b68c802}) + absl::Nanoseconds(229702057), + absl::Seconds(int64_t{0x23fec0307e4e9d3}) + absl::Nanoseconds(44555374)}; + absl::SetFlag(&FLAGS_test_flag_12, kValidDurations[0]); + + std::atomic<bool> stop{false}; + std::vector<std::thread> threads; + auto* handle = absl::FindCommandLineFlag("test_flag_12"); + for (int i = 0; i < kNumThreads; i++) { + threads.emplace_back([&]() { + while (!stop.load(std::memory_order_relaxed)) { + // Try loading the flag both directly and via a reflection + // handle. + absl::Duration v = absl::GetFlag(FLAGS_test_flag_12); + EXPECT_TRUE(v == kValidDurations[0] || v == kValidDurations[1]); + v = *handle->TryGet<absl::Duration>(); + EXPECT_TRUE(v == kValidDurations[0] || v == kValidDurations[1]); + } + }); + } + absl::Time end_time = absl::Now() + absl::Seconds(1); + int i = 0; + while (absl::Now() < end_time) { + absl::SetFlag(&FLAGS_test_flag_12, + kValidDurations[i++ % ABSL_ARRAYSIZE(kValidDurations)]); + } + stop.store(true, std::memory_order_relaxed); + for (auto& t : threads) t.join(); +} + +// -------------------------------------------------------------------- + int GetDflt1() { return 1; } } // namespace |