Revert "init: Add more diagnostics for signalfd hangs."
Revert commit 14f9c15e0560 ("init: Add more diagnostics for signalfd
hangs") because:
* That commit was intented to help with root-causing b/223076262.
* The root cause of b/223076262 has been fixed (not blocking SIGCHLD
in all threads in the init process).
Test: Treehugger
Change-Id: I586663ec0588e74a9d58512f7f31155398cf4f52
Signed-off-by: Bart Van Assche <bvanassche@google.com>
diff --git a/init/init.cpp b/init/init.cpp
index 540e2ca..4262191 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -739,33 +739,13 @@
HandlePowerctlMessage("shutdown,container");
}
-static constexpr std::chrono::milliseconds kDiagnosticTimeout = 10s;
-
-static void HandleSignalFd(bool one_off) {
+static void HandleSignalFd() {
signalfd_siginfo siginfo;
- auto started = std::chrono::steady_clock::now();
- do {
- ssize_t bytes_read = TEMP_FAILURE_RETRY(read(signal_fd, &siginfo, sizeof(siginfo)));
- if (bytes_read < 0 && errno == EAGAIN) {
- if (one_off) {
- return;
- }
- auto now = std::chrono::steady_clock::now();
- std::chrono::duration<double> waited = now - started;
- if (waited >= kDiagnosticTimeout) {
- LOG(ERROR) << "epoll() woke us up, but we waited with no SIGCHLD!";
- started = now;
- }
-
- std::this_thread::sleep_for(100ms);
- continue;
- }
- if (bytes_read != sizeof(siginfo)) {
- PLOG(ERROR) << "Failed to read siginfo from signal_fd";
- return;
- }
- break;
- } while (!one_off);
+ ssize_t bytes_read = TEMP_FAILURE_RETRY(read(signal_fd, &siginfo, sizeof(siginfo)));
+ if (bytes_read != sizeof(siginfo)) {
+ PLOG(ERROR) << "Failed to read siginfo from signal_fd";
+ return;
+ }
switch (siginfo.ssi_signo) {
case SIGCHLD:
@@ -820,14 +800,13 @@
LOG(FATAL) << "Failed to register a fork handler: " << strerror(result);
}
- signal_fd = signalfd(-1, &mask, SFD_CLOEXEC | SFD_NONBLOCK);
+ signal_fd = signalfd(-1, &mask, SFD_CLOEXEC);
if (signal_fd == -1) {
PLOG(FATAL) << "failed to create signalfd";
}
constexpr int flags = EPOLLIN | EPOLLPRI;
- auto handler = std::bind(HandleSignalFd, false);
- if (auto result = epoll->RegisterHandler(signal_fd, handler, flags); !result.ok()) {
+ if (auto result = epoll->RegisterHandler(signal_fd, HandleSignalFd, flags); !result.ok()) {
LOG(FATAL) << result.error();
}
}
@@ -956,32 +935,6 @@
return {};
}
-static void DumpPidFds(const std::string& prefix, pid_t pid) {
- std::error_code ec;
- std::string proc_dir = "/proc/" + std::to_string(pid) + "/fd";
- for (const auto& entry : std::filesystem::directory_iterator(proc_dir)) {
- std::string target;
- if (android::base::Readlink(entry.path(), &target)) {
- LOG(ERROR) << prefix << target;
- } else {
- LOG(ERROR) << prefix << entry.path();
- }
- }
-}
-
-static void DumpFile(const std::string& prefix, const std::string& file) {
- std::ifstream fp(file);
- if (!fp) {
- LOG(ERROR) << "Could not open " << file;
- return;
- }
-
- std::string line;
- while (std::getline(fp, line)) {
- LOG(ERROR) << prefix << line;
- }
-}
-
int SecondStageMain(int argc, char** argv) {
if (REBOOT_BOOTLOADER_ON_PANIC) {
InstallRebootSignalHandlers();
@@ -1155,7 +1108,7 @@
setpriority(PRIO_PROCESS, 0, 0);
while (true) {
// By default, sleep until something happens.
- std::chrono::milliseconds epoll_timeout{kDiagnosticTimeout};
+ std::optional<std::chrono::milliseconds> epoll_timeout;
auto shutdown_command = shutdown_state.CheckShutdown();
if (shutdown_command) {
@@ -1187,25 +1140,6 @@
auto epoll_result = epoll.Wait(epoll_timeout);
if (!epoll_result.ok()) {
LOG(ERROR) << epoll_result.error();
- } else if (*epoll_result <= 0 && Service::is_exec_service_running()) {
- static bool dumped_diagnostics = false;
- std::chrono::duration<double> waited =
- std::chrono::steady_clock::now() - Service::exec_service_started();
- if (waited >= kDiagnosticTimeout) {
- LOG(ERROR) << "Exec service is hung? Waited " << waited.count()
- << " without SIGCHLD";
- if (!dumped_diagnostics) {
- DumpPidFds("exec service opened: ", Service::exec_service_pid());
-
- std::string status_file =
- "/proc/" + std::to_string(Service::exec_service_pid()) + "/status";
- DumpFile("exec service: ", status_file);
- dumped_diagnostics = true;
-
- LOG(INFO) << "Attempting to handle any stuck SIGCHLDs...";
- HandleSignalFd(true);
- }
- }
}
if (!IsShuttingDown()) {
HandleControlMessages();