Merge "libprocessgroup: Remove max_processes from KillProcessGroup API" into main (ef9e7f85) · Commits · e / os / android_system_core

init/service.cpp

+5 −14

Original line number	Diff line number	Diff line
		@@ -194,7 +194,7 @@ void Service::NotifyStateChange(const std::string& new_state) const {
		}
		}

		void Service::KillProcessGroup(int signal, bool report_oneshot) {
		void Service::KillProcessGroup(int signal) {
		// If we've already seen a successful result from killProcessGroup*(), then we have removed
		// the cgroup already and calling these functions a second time will simply result in an error.
		// This is true regardless of which signal was sent.
		@@ -202,20 +202,11 @@ void Service::KillProcessGroup(int signal, bool report_oneshot) {
		if (!process_cgroup_empty_) {
		LOG(INFO) << "Sending signal " << signal << " to service '" << name_ << "' (pid " << pid_
		<< ") process group...";
		int max_processes = 0;
		int r;
		if (signal == SIGTERM) {
		r = killProcessGroupOnce(uid(), pid_, signal, &max_processes);
		r = killProcessGroupOnce(uid(), pid_, signal);
		} else {
		r = killProcessGroup(uid(), pid_, signal, &max_processes);
		}

		if (report_oneshot && max_processes > 0) {
		LOG(WARNING)
		<< "Killed " << max_processes
		<< " additional processes from a oneshot process group for service '" << name_
		<< "'. This is new behavior, previously child processes would not be killed in "
		"this case.";
		r = killProcessGroup(uid(), pid_, signal);
		}

		if (r == 0) process_cgroup_empty_ = true;
		@@ -265,7 +256,7 @@ void Service::SetProcessAttributesAndCaps(InterprocessFifo setsid_finished) {

		void Service::Reap(const siginfo_t& siginfo) {
		if (!(flags_ & SVC_ONESHOT) \|\| (flags_ & SVC_RESTART)) {
		KillProcessGroup(SIGKILL, false);
		KillProcessGroup(SIGKILL);
		} else {
		// Legacy behavior from ~2007 until Android R: this else branch did not exist and we did not
		// kill the process group in this case.
		@@ -273,7 +264,7 @@ void Service::Reap(const siginfo_t& siginfo) {
		// The new behavior in Android R is to kill these process groups in all cases. The
		// 'true' parameter instructions KillProcessGroup() to report a warning message where it
		// detects a difference in behavior has occurred.
		KillProcessGroup(SIGKILL, true);
		KillProcessGroup(SIGKILL);
		}
		}

init/service.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -160,7 +160,7 @@ class Service {
		private:
		void NotifyStateChange(const std::string& new_state) const;
		void StopOrReset(int how);
		void KillProcessGroup(int signal, bool report_oneshot = false);
		void KillProcessGroup(int signal);
		void SetProcessAttributesAndCaps(InterprocessFifo setsid_finished);
		void ResetFlagsForStart();
		Result<void> CheckConsole();

libprocessgroup/include/processgroup/processgroup.h

+2 −5

Original line number	Diff line number	Diff line
		@@ -67,14 +67,11 @@ void DropTaskProfilesResourceCaching();
		// Return 0 and removes the cgroup if there are no longer any processes in it.
		// Returns -1 in the case of an error occurring or if there are processes still running
		// even after retrying for up to 200ms.
		// If max_processes is not nullptr, it returns the maximum number of processes seen in the cgroup
		// during the killing process. Note that this can be 0 if all processes from the process group have
		// already been terminated.
		int killProcessGroup(uid_t uid, int initialPid, int signal, int* max_processes = nullptr);
		int killProcessGroup(uid_t uid, int initialPid, int signal);

		// Returns the same as killProcessGroup(), however it does not retry, which means
		// that it only returns 0 in the case that the cgroup exists and it contains no processes.
		int killProcessGroupOnce(uid_t uid, int initialPid, int signal, int* max_processes = nullptr);
		int killProcessGroupOnce(uid_t uid, int initialPid, int signal);

		// Sends the provided signal to all members of a process group, but does not wait for processes to
		// exit, or for the cgroup to be removed. Callers should also ensure that killProcessGroup is called

libprocessgroup/processgroup.cpp

+5 −13

Original line number	Diff line number	Diff line
		@@ -455,8 +455,7 @@ static int DoKillProcessGroupOnce(const char* cgroup, uid_t uid, int initialPid,
		return (!fd \|\| feof(fd.get())) ? processes : -1;
		}

		static int KillProcessGroup(uid_t uid, int initialPid, int signal, int retries,
		int* max_processes) {
		static int KillProcessGroup(uid_t uid, int initialPid, int signal, int retries) {
		CHECK_GE(uid, 0);
		CHECK_GT(initialPid, 0);

		@@ -468,16 +467,9 @@ static int KillProcessGroup(uid_t uid, int initialPid, int signal, int retries,

		std::chrono::steady_clock::time_point start = std::chrono::steady_clock::now();

		if (max_processes != nullptr) {
		*max_processes = 0;
		}

		int retry = retries;
		int processes;
		while ((processes = DoKillProcessGroupOnce(cgroup, uid, initialPid, signal)) > 0) {
		if (max_processes != nullptr && processes > *max_processes) {
		*max_processes = processes;
		}
		LOG(VERBOSE) << "Killed " << processes << " processes for processgroup " << initialPid;
		if (!CgroupsAvailable()) {
		// makes no sense to retry, because there are no cgroup_procs file
		@@ -540,12 +532,12 @@ static int KillProcessGroup(uid_t uid, int initialPid, int signal, int retries,
		}
		}

		int killProcessGroup(uid_t uid, int initialPid, int signal, int* max_processes) {
		return KillProcessGroup(uid, initialPid, signal, 40 /retries/, max_processes);
		int killProcessGroup(uid_t uid, int initialPid, int signal) {
		return KillProcessGroup(uid, initialPid, signal, 40 /retries/);
		}

		int killProcessGroupOnce(uid_t uid, int initialPid, int signal, int* max_processes) {
		return KillProcessGroup(uid, initialPid, signal, 0 /retries/, max_processes);
		int killProcessGroupOnce(uid_t uid, int initialPid, int signal) {
		return KillProcessGroup(uid, initialPid, signal, 0 /retries/);
		}

		int sendSignalToProcessGroup(uid_t uid, int initialPid, int signal) {