From fa4855403cdfb91b9c16f792041258ed819594c1 Mon Sep 17 00:00:00 2001 From: Derek Mauro Date: Thu, 9 Feb 2023 19:45:05 -0800 Subject: Rewrite KernelTimeout to support both absolute and relative timeouts APIs that take KernelTimeout as a parameter can now query if an absolute or relative timeout was requested. If the underlying API can only use one type of timeout, the code will do a reasonable conversion. The goal is to eventually enable the possibility of using wait times that are based on monotonic clocks that are safe against system clock steps. PiperOrigin-RevId: 508541507 Change-Id: Id08bf13515f3e1bfd78d88393cde98a6fd3ef72c --- .../internal/kernel_timeout_test.cc | 278 +++++++++++++++++++++ 1 file changed, 278 insertions(+) create mode 100644 absl/synchronization/internal/kernel_timeout_test.cc (limited to 'absl/synchronization/internal/kernel_timeout_test.cc') diff --git a/absl/synchronization/internal/kernel_timeout_test.cc b/absl/synchronization/internal/kernel_timeout_test.cc new file mode 100644 index 00000000..a89ae220 --- /dev/null +++ b/absl/synchronization/internal/kernel_timeout_test.cc @@ -0,0 +1,278 @@ +// Copyright 2023 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. + +#include "absl/synchronization/internal/kernel_timeout.h" + +#include + +#include "gtest/gtest.h" +#include "absl/base/config.h" +#include "absl/time/clock.h" +#include "absl/time/time.h" + +namespace { + +#if defined(ABSL_HAVE_ADDRESS_SANITIZER) || \ + defined(ABSL_HAVE_MEMORY_SANITIZER) || \ + defined(ABSL_HAVE_THREAD_SANITIZER) || defined(__ANDROID__) +constexpr absl::Duration kTimingBound = absl::Milliseconds(5); +#else +constexpr absl::Duration kTimingBound = absl::Microseconds(250); +#endif + +using absl::synchronization_internal::KernelTimeout; + +TEST(KernelTimeout, FiniteTimes) { + constexpr absl::Duration kDurationsToTest[] = { + absl::ZeroDuration(), + absl::Nanoseconds(1), + absl::Microseconds(1), + absl::Milliseconds(1), + absl::Seconds(1), + absl::Minutes(1), + absl::Hours(1), + absl::Hours(1000), + -absl::Nanoseconds(1), + -absl::Microseconds(1), + -absl::Milliseconds(1), + -absl::Seconds(1), + -absl::Minutes(1), + -absl::Hours(1), + -absl::Hours(1000), + }; + + for (auto duration : kDurationsToTest) { + const absl::Time now = absl::Now(); + const absl::Time when = now + duration; + SCOPED_TRACE(duration); + KernelTimeout t(when); + EXPECT_TRUE(t.has_timeout()); + EXPECT_TRUE(t.is_absolute_timeout()); + EXPECT_FALSE(t.is_relative_timeout()); + EXPECT_EQ(absl::TimeFromTimespec(t.MakeAbsTimespec()), when); + // MakeRelativeTimespec() doesn't quite round trip when using an absolute + // time, but it should get pretty close. Past times are converted to zero + // durations. + EXPECT_LE( + absl::AbsDuration(absl::DurationFromTimespec(t.MakeRelativeTimespec()) - + std::max(duration, absl::ZeroDuration())), + kTimingBound); + EXPECT_EQ(absl::FromUnixNanos(t.MakeAbsNanos()), when); + EXPECT_LE(absl::AbsDuration(absl::Milliseconds(t.InMillisecondsFromNow()) - + std::max(duration, absl::ZeroDuration())), + absl::Milliseconds(5)); + } +} + +TEST(KernelTimeout, InfiniteFuture) { + KernelTimeout t(absl::InfiniteFuture()); + EXPECT_FALSE(t.has_timeout()); + // Callers are expected to check has_timeout() instead of using the methods + // below, but we do try to do something reasonable if they don't. We may not + // be able to round-trip back to absl::InfiniteDuration() or + // absl::InfiniteFuture(), but we should return a very large value. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_EQ(t.InMillisecondsFromNow(), + std::numeric_limits::max()); +} + +TEST(KernelTimeout, DefaultConstructor) { + // The default constructor is equivalent to absl::InfiniteFuture(). + KernelTimeout t; + EXPECT_FALSE(t.has_timeout()); + // Callers are expected to check has_timeout() instead of using the methods + // below, but we do try to do something reasonable if they don't. We may not + // be able to round-trip back to absl::InfiniteDuration() or + // absl::InfiniteFuture(), but we should return a very large value. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_EQ(t.InMillisecondsFromNow(), + std::numeric_limits::max()); +} + +TEST(KernelTimeout, TimeMaxNanos) { + // Time >= kMaxNanos should behave as no timeout. + KernelTimeout t(absl::FromUnixNanos(std::numeric_limits::max())); + EXPECT_FALSE(t.has_timeout()); + // Callers are expected to check has_timeout() instead of using the methods + // below, but we do try to do something reasonable if they don't. We may not + // be able to round-trip back to absl::InfiniteDuration() or + // absl::InfiniteFuture(), but we should return a very large value. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_EQ(t.InMillisecondsFromNow(), + std::numeric_limits::max()); +} + +TEST(KernelTimeout, Never) { + // KernelTimeout::Never() is equivalent to absl::InfiniteFuture(). + KernelTimeout t = KernelTimeout::Never(); + EXPECT_FALSE(t.has_timeout()); + // Callers are expected to check has_timeout() instead of using the methods + // below, but we do try to do something reasonable if they don't. We may not + // be able to round-trip back to absl::InfiniteDuration() or + // absl::InfiniteFuture(), but we should return a very large value. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_EQ(t.InMillisecondsFromNow(), + std::numeric_limits::max()); +} + +TEST(KernelTimeout, InfinitePast) { + KernelTimeout t(absl::InfinitePast()); + EXPECT_TRUE(t.has_timeout()); + EXPECT_TRUE(t.is_absolute_timeout()); + EXPECT_FALSE(t.is_relative_timeout()); + EXPECT_LE(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::FromUnixNanos(1)); + EXPECT_EQ(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::ZeroDuration()); + EXPECT_LE(absl::FromUnixNanos(t.MakeAbsNanos()), absl::FromUnixNanos(1)); + EXPECT_EQ(t.InMillisecondsFromNow(), KernelTimeout::DWord{0}); +} + +TEST(KernelTimeout, FiniteDurations) { + constexpr absl::Duration kDurationsToTest[] = { + absl::ZeroDuration(), + absl::Nanoseconds(1), + absl::Microseconds(1), + absl::Milliseconds(1), + absl::Seconds(1), + absl::Minutes(1), + absl::Hours(1), + absl::Hours(1000), + }; + + for (auto duration : kDurationsToTest) { + SCOPED_TRACE(duration); + KernelTimeout t(duration); + EXPECT_TRUE(t.has_timeout()); + EXPECT_FALSE(t.is_absolute_timeout()); + EXPECT_TRUE(t.is_relative_timeout()); + EXPECT_LE(absl::AbsDuration(absl::Now() + duration - + absl::TimeFromTimespec(t.MakeAbsTimespec())), + absl::Milliseconds(5)); + EXPECT_EQ(absl::DurationFromTimespec(t.MakeRelativeTimespec()), duration); + EXPECT_LE(absl::AbsDuration(absl::Now() + duration - + absl::FromUnixNanos(t.MakeAbsNanos())), + absl::Milliseconds(5)); + EXPECT_LE(absl::Milliseconds(t.InMillisecondsFromNow()) - duration, + absl::Milliseconds(5)); + } +} + +TEST(KernelTimeout, NegativeDurations) { + constexpr absl::Duration kDurationsToTest[] = { + -absl::ZeroDuration(), + -absl::Nanoseconds(1), + -absl::Microseconds(1), + -absl::Milliseconds(1), + -absl::Seconds(1), + -absl::Minutes(1), + -absl::Hours(1), + -absl::Hours(1000), + -absl::InfiniteDuration(), + }; + + for (auto duration : kDurationsToTest) { + // Negative durations should all be converted to zero durations or "now". + SCOPED_TRACE(duration); + KernelTimeout t(duration); + EXPECT_TRUE(t.has_timeout()); + EXPECT_FALSE(t.is_absolute_timeout()); + EXPECT_TRUE(t.is_relative_timeout()); + EXPECT_LE(absl::AbsDuration(absl::Now() - + absl::TimeFromTimespec(t.MakeAbsTimespec())), + absl::Milliseconds(5)); + EXPECT_EQ(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::ZeroDuration()); + EXPECT_LE( + absl::AbsDuration(absl::Now() - absl::FromUnixNanos(t.MakeAbsNanos())), + absl::Milliseconds(5)); + EXPECT_EQ(t.InMillisecondsFromNow(), KernelTimeout::DWord{0}); + } +} + +TEST(KernelTimeout, InfiniteDuration) { + KernelTimeout t(absl::InfiniteDuration()); + EXPECT_FALSE(t.has_timeout()); + // Callers are expected to check has_timeout() instead of using the methods + // below, but we do try to do something reasonable if they don't. We may not + // be able to round-trip back to absl::InfiniteDuration() or + // absl::InfiniteFuture(), but we should return a very large value. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_EQ(t.InMillisecondsFromNow(), + std::numeric_limits::max()); +} + +TEST(KernelTimeout, DurationMaxNanos) { + // Duration >= kMaxNanos should behave as no timeout. + KernelTimeout t(absl::Nanoseconds(std::numeric_limits::max())); + EXPECT_FALSE(t.has_timeout()); + // Callers are expected to check has_timeout() instead of using the methods + // below, but we do try to do something reasonable if they don't. We may not + // be able to round-trip back to absl::InfiniteDuration() or + // absl::InfiniteFuture(), but we should return a very large value. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_EQ(t.InMillisecondsFromNow(), + std::numeric_limits::max()); +} + +TEST(KernelTimeout, OverflowNanos) { + // Test what happens when KernelTimeout is constructed with an absl::Duration + // that would overflow now_nanos + duration. + int64_t now_nanos = absl::ToUnixNanos(absl::Now()); + int64_t limit = std::numeric_limits::max() - now_nanos; + absl::Duration duration = absl::Nanoseconds(limit) + absl::Seconds(1); + KernelTimeout t(duration); + EXPECT_TRUE(t.has_timeout()); + // Timeouts should still be far in the future. + EXPECT_GT(absl::TimeFromTimespec(t.MakeAbsTimespec()), + absl::Now() + absl::Hours(100000)); + EXPECT_GT(absl::DurationFromTimespec(t.MakeRelativeTimespec()), + absl::Hours(100000)); + EXPECT_GT(absl::FromUnixNanos(t.MakeAbsNanos()), + absl::Now() + absl::Hours(100000)); + EXPECT_LE(absl::Milliseconds(t.InMillisecondsFromNow()) - duration, + absl::Milliseconds(5)); +} + +} // namespace -- cgit v1.2.3