Merge "init: reap zombies only after kill(-pid, ...)" am: a51c40ce35 am: 0924b32c1f am: 419a9ef8f1 (2afdb6d5) · Commits · e / os / android_system_core

init/service.cpp

+20 −11

Original line number	Original line	Diff line number	Diff line
	@@ -34,6 +34,7 @@
	#include <android-base/logging.h>		#include <android-base/logging.h>
	#include <android-base/parseint.h>		#include <android-base/parseint.h>
	#include <android-base/properties.h>		#include <android-base/properties.h>
			#include <android-base/scopeguard.h>
	#include <android-base/stringprintf.h>		#include <android-base/stringprintf.h>
	#include <android-base/strings.h>		#include <android-base/strings.h>
	#include <processgroup/processgroup.h>		#include <processgroup/processgroup.h>
	@@ -47,6 +48,7 @@
	using android::base::boot_clock;		using android::base::boot_clock;
	using android::base::GetProperty;		using android::base::GetProperty;
	using android::base::Join;		using android::base::Join;
			using android::base::make_scope_guard;
	using android::base::ParseInt;		using android::base::ParseInt;
	using android::base::StartsWith;		using android::base::StartsWith;
	using android::base::StringPrintf;		using android::base::StringPrintf;
	@@ -1088,14 +1090,24 @@ void ServiceManager::DumpState() const {
	}		}

	bool ServiceManager::ReapOneProcess() {		bool ServiceManager::ReapOneProcess() {
	int status;		siginfo_t siginfo = {};
	pid_t pid = TEMP_FAILURE_RETRY(waitpid(-1, &status, WNOHANG));		// This returns a zombie pid or informs us that there are no zombies left to be reaped.
	if (pid == 0) {		// It does NOT reap the pid; that is done below.
			if (TEMP_FAILURE_RETRY(waitid(P_ALL, 0, &siginfo, WEXITED \| WNOHANG \| WNOWAIT)) != 0) {
			PLOG(ERROR) << "waitid failed";
	return false;		return false;
	} else if (pid == -1) {		}
	PLOG(ERROR) << "waitpid failed";
	return false;		auto pid = siginfo.si_pid;
	} else if (PropertyChildReap(pid)) {		if (pid == 0) return false;

			// At this point we know we have a zombie pid, so we use this scopeguard to reap the pid
			// whenever the function returns from this point forward.
			// We do NOT want to reap the zombie earlier as in Service::Reap(), we kill(-pid, ...) and we
			// want the pid to remain valid throughout that (and potentially future) usages.
			auto reaper = make_scope_guard([pid] { TEMP_FAILURE_RETRY(waitpid(pid, nullptr, WNOHANG)); });

			if (PropertyChildReap(pid)) {
	return true;		return true;
	}		}

	@@ -1112,14 +1124,11 @@ bool ServiceManager::ReapOneProcess() {
	name = StringPrintf("Untracked pid %d", pid);		name = StringPrintf("Untracked pid %d", pid);
	}		}

			auto status = siginfo.si_status;
	if (WIFEXITED(status)) {		if (WIFEXITED(status)) {
	LOG(INFO) << name << " exited with status " << WEXITSTATUS(status) << wait_string;		LOG(INFO) << name << " exited with status " << WEXITSTATUS(status) << wait_string;
	} else if (WIFSIGNALED(status)) {		} else if (WIFSIGNALED(status)) {
	LOG(INFO) << name << " killed by signal " << WTERMSIG(status) << wait_string;		LOG(INFO) << name << " killed by signal " << WTERMSIG(status) << wait_string;
	} else if (WIFSTOPPED(status)) {
	LOG(INFO) << name << " stopped by signal " << WSTOPSIG(status) << wait_string;
	} else {
	LOG(INFO) << name << " state changed" << wait_string;
	}		}

	if (!svc) {		if (!svc) {