diff options
-rw-r--r-- | pkg/sentry/syscalls/linux/sys_time.go | 39 | ||||
-rw-r--r-- | test/syscalls/linux/clock_nanosleep.cc | 86 |
2 files changed, 73 insertions, 52 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_time.go b/pkg/sentry/syscalls/linux/sys_time.go index 4b3f043a2..b887fa9d7 100644 --- a/pkg/sentry/syscalls/linux/sys_time.go +++ b/pkg/sentry/syscalls/linux/sys_time.go @@ -15,6 +15,7 @@ package linux import ( + "fmt" "time" "gvisor.dev/gvisor/pkg/abi/linux" @@ -228,41 +229,35 @@ func clockNanosleepFor(t *kernel.Task, c ktime.Clock, dur time.Duration, rem use timer.Destroy() - var remaining time.Duration - // Did we just block for the entire duration? - if err == syserror.ETIMEDOUT { - remaining = 0 - } else { - remaining = dur - after.Sub(start) + switch err { + case syserror.ETIMEDOUT: + // Slept for entire timeout. + return nil + case syserror.ErrInterrupted: + // Interrupted. + remaining := dur - after.Sub(start) if remaining < 0 { remaining = time.Duration(0) } - } - // Copy out remaining time. - if err != nil && rem != usermem.Addr(0) { - timeleft := linux.NsecToTimespec(remaining.Nanoseconds()) - if err := copyTimespecOut(t, rem, &timeleft); err != nil { - return err + // Copy out remaining time. + if rem != 0 { + timeleft := linux.NsecToTimespec(remaining.Nanoseconds()) + if err := copyTimespecOut(t, rem, &timeleft); err != nil { + return err + } } - } - - // Did we just block for the entire duration? - if err == syserror.ETIMEDOUT { - return nil - } - // If interrupted, arrange for a restart with the remaining duration. - if err == syserror.ErrInterrupted { + // Arrange for a restart with the remaining duration. t.SetSyscallRestartBlock(&clockNanosleepRestartBlock{ c: c, duration: remaining, rem: rem, }) return kernel.ERESTART_RESTARTBLOCK + default: + panic(fmt.Sprintf("Impossible BlockWithTimer error %v", err)) } - - return err } // Nanosleep implements linux syscall Nanosleep(2). diff --git a/test/syscalls/linux/clock_nanosleep.cc b/test/syscalls/linux/clock_nanosleep.cc index 52a69d230..b55cddc52 100644 --- a/test/syscalls/linux/clock_nanosleep.cc +++ b/test/syscalls/linux/clock_nanosleep.cc @@ -43,7 +43,7 @@ int sys_clock_nanosleep(clockid_t clkid, int flags, PosixErrorOr<absl::Time> GetTime(clockid_t clk) { struct timespec ts = {}; - int rc = clock_gettime(clk, &ts); + const int rc = clock_gettime(clk, &ts); MaybeSave(); if (rc < 0) { return PosixError(errno, "clock_gettime"); @@ -67,31 +67,32 @@ TEST_P(WallClockNanosleepTest, InvalidValues) { } TEST_P(WallClockNanosleepTest, SleepOneSecond) { - absl::Duration const duration = absl::Seconds(1); - struct timespec dur = absl::ToTimespec(duration); + constexpr absl::Duration kSleepDuration = absl::Seconds(1); + struct timespec duration = absl::ToTimespec(kSleepDuration); - absl::Time const before = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); - EXPECT_THAT(RetryEINTR(sys_clock_nanosleep)(GetParam(), 0, &dur, &dur), - SyscallSucceeds()); - absl::Time const after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); + const absl::Time before = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); + EXPECT_THAT( + RetryEINTR(sys_clock_nanosleep)(GetParam(), 0, &duration, &duration), + SyscallSucceeds()); + const absl::Time after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); - EXPECT_GE(after - before, duration); + EXPECT_GE(after - before, kSleepDuration); } TEST_P(WallClockNanosleepTest, InterruptedNanosleep) { - absl::Duration const duration = absl::Seconds(60); - struct timespec dur = absl::ToTimespec(duration); + constexpr absl::Duration kSleepDuration = absl::Seconds(60); + struct timespec duration = absl::ToTimespec(kSleepDuration); // Install no-op signal handler for SIGALRM. struct sigaction sa = {}; sigfillset(&sa.sa_mask); sa.sa_handler = +[](int signo) {}; - auto const cleanup_sa = + const auto cleanup_sa = ASSERT_NO_ERRNO_AND_VALUE(ScopedSigaction(SIGALRM, sa)); // Measure time since setting the alarm, since the alarm will interrupt the // sleep and hence determine how long we sleep. - absl::Time const before = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); + const absl::Time before = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); // Set an alarm to go off while sleeping. struct itimerval timer = {}; @@ -99,26 +100,51 @@ TEST_P(WallClockNanosleepTest, InterruptedNanosleep) { timer.it_value.tv_usec = 0; timer.it_interval.tv_sec = 1; timer.it_interval.tv_usec = 0; - auto const cleanup = + const auto cleanup = ASSERT_NO_ERRNO_AND_VALUE(ScopedItimer(ITIMER_REAL, timer)); - EXPECT_THAT(sys_clock_nanosleep(GetParam(), 0, &dur, &dur), + EXPECT_THAT(sys_clock_nanosleep(GetParam(), 0, &duration, &duration), SyscallFailsWithErrno(EINTR)); - absl::Time const after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); + const absl::Time after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); - absl::Duration const remaining = absl::DurationFromTimespec(dur); - EXPECT_GE(after - before + remaining, duration); + // Remaining time updated. + const absl::Duration remaining = absl::DurationFromTimespec(duration); + EXPECT_GE(after - before + remaining, kSleepDuration); +} + +// Remaining time is *not* updated if nanosleep completes uninterrupted. +TEST_P(WallClockNanosleepTest, UninterruptedNanosleep) { + constexpr absl::Duration kSleepDuration = absl::Milliseconds(10); + const struct timespec duration = absl::ToTimespec(kSleepDuration); + + while (true) { + constexpr int kRemainingMagic = 42; + struct timespec remaining; + remaining.tv_sec = kRemainingMagic; + remaining.tv_nsec = kRemainingMagic; + + int ret = sys_clock_nanosleep(GetParam(), 0, &duration, &remaining); + if (ret == EINTR) { + // Retry from beginning. We want a single uninterrupted call. + continue; + } + + EXPECT_THAT(ret, SyscallSucceeds()); + EXPECT_EQ(remaining.tv_sec, kRemainingMagic); + EXPECT_EQ(remaining.tv_nsec, kRemainingMagic); + break; + } } TEST_P(WallClockNanosleepTest, SleepUntil) { - absl::Time const now = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); - absl::Time const until = now + absl::Seconds(2); - struct timespec ts = absl::ToTimespec(until); + const absl::Time now = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); + const absl::Time until = now + absl::Seconds(2); + const struct timespec ts = absl::ToTimespec(until); EXPECT_THAT( RetryEINTR(sys_clock_nanosleep)(GetParam(), TIMER_ABSTIME, &ts, nullptr), SyscallSucceeds()); - absl::Time const after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); + const absl::Time after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(GetParam())); EXPECT_GE(after, until); } @@ -127,8 +153,8 @@ INSTANTIATE_TEST_SUITE_P(Sleepers, WallClockNanosleepTest, ::testing::Values(CLOCK_REALTIME, CLOCK_MONOTONIC)); TEST(ClockNanosleepProcessTest, SleepFiveSeconds) { - absl::Duration const kDuration = absl::Seconds(5); - struct timespec dur = absl::ToTimespec(kDuration); + const absl::Duration kSleepDuration = absl::Seconds(5); + struct timespec duration = absl::ToTimespec(kSleepDuration); // Ensure that CLOCK_PROCESS_CPUTIME_ID advances. std::atomic<bool> done(false); @@ -136,16 +162,16 @@ TEST(ClockNanosleepProcessTest, SleepFiveSeconds) { while (!done.load()) { } }); - auto const cleanup_done = Cleanup([&] { done.store(true); }); + const auto cleanup_done = Cleanup([&] { done.store(true); }); - absl::Time const before = + const absl::Time before = ASSERT_NO_ERRNO_AND_VALUE(GetTime(CLOCK_PROCESS_CPUTIME_ID)); - EXPECT_THAT( - RetryEINTR(sys_clock_nanosleep)(CLOCK_PROCESS_CPUTIME_ID, 0, &dur, &dur), - SyscallSucceeds()); - absl::Time const after = + EXPECT_THAT(RetryEINTR(sys_clock_nanosleep)(CLOCK_PROCESS_CPUTIME_ID, 0, + &duration, &duration), + SyscallSucceeds()); + const absl::Time after = ASSERT_NO_ERRNO_AND_VALUE(GetTime(CLOCK_PROCESS_CPUTIME_ID)); - EXPECT_GE(after - before, kDuration); + EXPECT_GE(after - before, kSleepDuration); } } // namespace |