diff options
| -rw-r--r-- | test/syscalls/linux/itimer.cc | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/test/syscalls/linux/itimer.cc b/test/syscalls/linux/itimer.cc index dd981a278..e397d5f57 100644 --- a/test/syscalls/linux/itimer.cc +++ b/test/syscalls/linux/itimer.cc @@ -267,8 +267,19 @@ int TestSIGPROFFairness(absl::Duration sleep) { // Random save/restore is disabled as it introduces additional latency and // unpredictable distribution patterns. TEST(ItimerTest, DeliversSIGPROFToThreadsRoughlyFairlyActive_NoRandomSave) { - // TODO(b/143247272): CPU time accounting is inaccurate for the KVM platform. - SKIP_IF(GvisorPlatform() == Platform::kKVM); + // On the KVM and ptrace platforms, switches between sentry and application + // context are sometimes extremely slow, causing the itimer to send SIGPROF to + // a thread that either already has one pending or has had SIGPROF delivered, + // but hasn't handled it yet (and thus therefore still has SIGPROF masked). In + // either case, since itimer signals are group-directed, signal sending falls + // back to notifying the thread group leader. ItimerSignalTest() fails if "too + // many" signals are delivered to the thread group leader, so these tests are + // flaky on these platforms. + // + // TODO(b/143247272): Clarify why context switches are so slow on KVM. + const auto gvisor_platform = GvisorPlatform(); + SKIP_IF(gvisor_platform == Platform::kKVM || + gvisor_platform == Platform::kPtrace); pid_t child; int execve_errno; @@ -291,8 +302,10 @@ TEST(ItimerTest, DeliversSIGPROFToThreadsRoughlyFairlyActive_NoRandomSave) { // Random save/restore is disabled as it introduces additional latency and // unpredictable distribution patterns. TEST(ItimerTest, DeliversSIGPROFToThreadsRoughlyFairlyIdle_NoRandomSave) { - // TODO(b/143247272): CPU time accounting is inaccurate for the KVM platform. - SKIP_IF(GvisorPlatform() == Platform::kKVM); + // See comment in DeliversSIGPROFToThreadsRoughlyFairlyActive. + const auto gvisor_platform = GvisorPlatform(); + SKIP_IF(gvisor_platform == Platform::kKVM || + gvisor_platform == Platform::kPtrace); pid_t child; int execve_errno; |