about summary refs log tree commit diff
path: root/third_party/abseil_cpp/absl/base/spinlock_test_common.cc
diff options
context:
space:
mode:
authorVincent Ambo <mail@tazj.in>2022-02-07T23·05+0300
committerclbot <clbot@tvl.fyi>2022-02-07T23·09+0000
commit5aa5d282eac56a21e74611c1cdbaa97bb5db2dca (patch)
tree8cc5dce8157a1470ff76719dd15d65f648a05522 /third_party/abseil_cpp/absl/base/spinlock_test_common.cc
parenta25675804c4f429fab5ee5201fe25e89865dfd13 (diff)
chore(3p/abseil_cpp): unvendor abseil_cpp r/3786
we weren't actually using these sources anymore, okay?

Change-Id: If701571d9716de308d3512e1eb22c35db0877a66
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Diffstat (limited to 'third_party/abseil_cpp/absl/base/spinlock_test_common.cc')
-rw-r--r--third_party/abseil_cpp/absl/base/spinlock_test_common.cc271
1 files changed, 0 insertions, 271 deletions
diff --git a/third_party/abseil_cpp/absl/base/spinlock_test_common.cc b/third_party/abseil_cpp/absl/base/spinlock_test_common.cc
deleted file mode 100644
index dee266e4f4c0..000000000000
--- a/third_party/abseil_cpp/absl/base/spinlock_test_common.cc
+++ /dev/null
@@ -1,271 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// A bunch of threads repeatedly hash an array of ints protected by a
-// spinlock.  If the spinlock is working properly, all elements of the
-// array should be equal at the end of the test.
-
-#include <cstdint>
-#include <limits>
-#include <random>
-#include <thread>  // NOLINT(build/c++11)
-#include <type_traits>
-#include <vector>
-
-#include "gtest/gtest.h"
-#include "absl/base/attributes.h"
-#include "absl/base/config.h"
-#include "absl/base/internal/low_level_scheduling.h"
-#include "absl/base/internal/scheduling_mode.h"
-#include "absl/base/internal/spinlock.h"
-#include "absl/base/internal/sysinfo.h"
-#include "absl/base/macros.h"
-#include "absl/synchronization/blocking_counter.h"
-#include "absl/synchronization/notification.h"
-
-constexpr int32_t kNumThreads = 10;
-constexpr int32_t kIters = 1000;
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace base_internal {
-
-// This is defined outside of anonymous namespace so that it can be
-// a friend of SpinLock to access protected methods for testing.
-struct SpinLockTest {
-  static uint32_t EncodeWaitCycles(int64_t wait_start_time,
-                                   int64_t wait_end_time) {
-    return SpinLock::EncodeWaitCycles(wait_start_time, wait_end_time);
-  }
-  static uint64_t DecodeWaitCycles(uint32_t lock_value) {
-    return SpinLock::DecodeWaitCycles(lock_value);
-  }
-};
-
-namespace {
-
-static constexpr int kArrayLength = 10;
-static uint32_t values[kArrayLength];
-
-ABSL_CONST_INIT static SpinLock static_cooperative_spinlock(
-    absl::kConstInit, base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL);
-ABSL_CONST_INIT static SpinLock static_noncooperative_spinlock(
-    absl::kConstInit, base_internal::SCHEDULE_KERNEL_ONLY);
-
-// Simple integer hash function based on the public domain lookup2 hash.
-// http://burtleburtle.net/bob/c/lookup2.c
-static uint32_t Hash32(uint32_t a, uint32_t c) {
-  uint32_t b = 0x9e3779b9UL;  // The golden ratio; an arbitrary value.
-  a -= b; a -= c; a ^= (c >> 13);
-  b -= c; b -= a; b ^= (a << 8);
-  c -= a; c -= b; c ^= (b >> 13);
-  a -= b; a -= c; a ^= (c >> 12);
-  b -= c; b -= a; b ^= (a << 16);
-  c -= a; c -= b; c ^= (b >> 5);
-  a -= b; a -= c; a ^= (c >> 3);
-  b -= c; b -= a; b ^= (a << 10);
-  c -= a; c -= b; c ^= (b >> 15);
-  return c;
-}
-
-static void TestFunction(int thread_salt, SpinLock* spinlock) {
-  for (int i = 0; i < kIters; i++) {
-    SpinLockHolder h(spinlock);
-    for (int j = 0; j < kArrayLength; j++) {
-      const int index = (j + thread_salt) % kArrayLength;
-      values[index] = Hash32(values[index], thread_salt);
-      std::this_thread::yield();
-    }
-  }
-}
-
-static void ThreadedTest(SpinLock* spinlock) {
-  std::vector<std::thread> threads;
-  for (int i = 0; i < kNumThreads; ++i) {
-    threads.push_back(std::thread(TestFunction, i, spinlock));
-  }
-  for (auto& thread : threads) {
-    thread.join();
-  }
-
-  SpinLockHolder h(spinlock);
-  for (int i = 1; i < kArrayLength; i++) {
-    EXPECT_EQ(values[0], values[i]);
-  }
-}
-
-#ifndef ABSL_HAVE_THREAD_SANITIZER
-static_assert(std::is_trivially_destructible<SpinLock>(), "");
-#endif
-
-TEST(SpinLock, StackNonCooperativeDisablesScheduling) {
-  SpinLock spinlock(base_internal::SCHEDULE_KERNEL_ONLY);
-  spinlock.Lock();
-  EXPECT_FALSE(base_internal::SchedulingGuard::ReschedulingIsAllowed());
-  spinlock.Unlock();
-}
-
-TEST(SpinLock, StaticNonCooperativeDisablesScheduling) {
-  static_noncooperative_spinlock.Lock();
-  EXPECT_FALSE(base_internal::SchedulingGuard::ReschedulingIsAllowed());
-  static_noncooperative_spinlock.Unlock();
-}
-
-TEST(SpinLock, WaitCyclesEncoding) {
-  // These are implementation details not exported by SpinLock.
-  const int kProfileTimestampShift = 7;
-  const int kLockwordReservedShift = 3;
-  const uint32_t kSpinLockSleeper = 8;
-
-  // We should be able to encode up to (1^kMaxCycleBits - 1) without clamping
-  // but the lower kProfileTimestampShift will be dropped.
-  const int kMaxCyclesShift =
-    32 - kLockwordReservedShift + kProfileTimestampShift;
-  const uint64_t kMaxCycles = (int64_t{1} << kMaxCyclesShift) - 1;
-
-  // These bits should be zero after encoding.
-  const uint32_t kLockwordReservedMask = (1 << kLockwordReservedShift) - 1;
-
-  // These bits are dropped when wait cycles are encoded.
-  const uint64_t kProfileTimestampMask = (1 << kProfileTimestampShift) - 1;
-
-  // Test a bunch of random values
-  std::default_random_engine generator;
-  // Shift to avoid overflow below.
-  std::uniform_int_distribution<uint64_t> time_distribution(
-      0, std::numeric_limits<uint64_t>::max() >> 4);
-  std::uniform_int_distribution<uint64_t> cycle_distribution(0, kMaxCycles);
-
-  for (int i = 0; i < 100; i++) {
-    int64_t start_time = time_distribution(generator);
-    int64_t cycles = cycle_distribution(generator);
-    int64_t end_time = start_time + cycles;
-    uint32_t lock_value = SpinLockTest::EncodeWaitCycles(start_time, end_time);
-    EXPECT_EQ(0, lock_value & kLockwordReservedMask);
-    uint64_t decoded = SpinLockTest::DecodeWaitCycles(lock_value);
-    EXPECT_EQ(0, decoded & kProfileTimestampMask);
-    EXPECT_EQ(cycles & ~kProfileTimestampMask, decoded);
-  }
-
-  // Test corner cases
-  int64_t start_time = time_distribution(generator);
-  EXPECT_EQ(kSpinLockSleeper,
-            SpinLockTest::EncodeWaitCycles(start_time, start_time));
-  EXPECT_EQ(0, SpinLockTest::DecodeWaitCycles(0));
-  EXPECT_EQ(0, SpinLockTest::DecodeWaitCycles(kLockwordReservedMask));
-  EXPECT_EQ(kMaxCycles & ~kProfileTimestampMask,
-            SpinLockTest::DecodeWaitCycles(~kLockwordReservedMask));
-
-  // Check that we cannot produce kSpinLockSleeper during encoding.
-  int64_t sleeper_cycles =
-      kSpinLockSleeper << (kProfileTimestampShift - kLockwordReservedShift);
-  uint32_t sleeper_value =
-      SpinLockTest::EncodeWaitCycles(start_time, start_time + sleeper_cycles);
-  EXPECT_NE(sleeper_value, kSpinLockSleeper);
-
-  // Test clamping
-  uint32_t max_value =
-    SpinLockTest::EncodeWaitCycles(start_time, start_time + kMaxCycles);
-  uint64_t max_value_decoded = SpinLockTest::DecodeWaitCycles(max_value);
-  uint64_t expected_max_value_decoded = kMaxCycles & ~kProfileTimestampMask;
-  EXPECT_EQ(expected_max_value_decoded, max_value_decoded);
-
-  const int64_t step = (1 << kProfileTimestampShift);
-  uint32_t after_max_value =
-    SpinLockTest::EncodeWaitCycles(start_time, start_time + kMaxCycles + step);
-  uint64_t after_max_value_decoded =
-      SpinLockTest::DecodeWaitCycles(after_max_value);
-  EXPECT_EQ(expected_max_value_decoded, after_max_value_decoded);
-
-  uint32_t before_max_value = SpinLockTest::EncodeWaitCycles(
-      start_time, start_time + kMaxCycles - step);
-  uint64_t before_max_value_decoded =
-    SpinLockTest::DecodeWaitCycles(before_max_value);
-  EXPECT_GT(expected_max_value_decoded, before_max_value_decoded);
-}
-
-TEST(SpinLockWithThreads, StackSpinLock) {
-  SpinLock spinlock;
-  ThreadedTest(&spinlock);
-}
-
-TEST(SpinLockWithThreads, StackCooperativeSpinLock) {
-  SpinLock spinlock(base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL);
-  ThreadedTest(&spinlock);
-}
-
-TEST(SpinLockWithThreads, StackNonCooperativeSpinLock) {
-  SpinLock spinlock(base_internal::SCHEDULE_KERNEL_ONLY);
-  ThreadedTest(&spinlock);
-}
-
-TEST(SpinLockWithThreads, StaticCooperativeSpinLock) {
-  ThreadedTest(&static_cooperative_spinlock);
-}
-
-TEST(SpinLockWithThreads, StaticNonCooperativeSpinLock) {
-  ThreadedTest(&static_noncooperative_spinlock);
-}
-
-TEST(SpinLockWithThreads, DoesNotDeadlock) {
-  struct Helper {
-    static void NotifyThenLock(Notification* locked, SpinLock* spinlock,
-                               BlockingCounter* b) {
-      locked->WaitForNotification();  // Wait for LockThenWait() to hold "s".
-      b->DecrementCount();
-      SpinLockHolder l(spinlock);
-    }
-
-    static void LockThenWait(Notification* locked, SpinLock* spinlock,
-                             BlockingCounter* b) {
-      SpinLockHolder l(spinlock);
-      locked->Notify();
-      b->Wait();
-    }
-
-    static void DeadlockTest(SpinLock* spinlock, int num_spinners) {
-      Notification locked;
-      BlockingCounter counter(num_spinners);
-      std::vector<std::thread> threads;
-
-      threads.push_back(
-          std::thread(Helper::LockThenWait, &locked, spinlock, &counter));
-      for (int i = 0; i < num_spinners; ++i) {
-        threads.push_back(
-            std::thread(Helper::NotifyThenLock, &locked, spinlock, &counter));
-      }
-
-      for (auto& thread : threads) {
-        thread.join();
-      }
-    }
-  };
-
-  SpinLock stack_cooperative_spinlock(
-      base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL);
-  SpinLock stack_noncooperative_spinlock(base_internal::SCHEDULE_KERNEL_ONLY);
-  Helper::DeadlockTest(&stack_cooperative_spinlock,
-                       base_internal::NumCPUs() * 2);
-  Helper::DeadlockTest(&stack_noncooperative_spinlock,
-                       base_internal::NumCPUs() * 2);
-  Helper::DeadlockTest(&static_cooperative_spinlock,
-                       base_internal::NumCPUs() * 2);
-  Helper::DeadlockTest(&static_noncooperative_spinlock,
-                       base_internal::NumCPUs() * 2);
-}
-
-}  // namespace
-}  // namespace base_internal
-ABSL_NAMESPACE_END
-}  // namespace absl