Merge "libprocessgroup: Rework SetupCgroup()" (d35f56b1) · Commits · e / os / android_system_core

libprocessgroup/setup/cgroup_map_write.cpp

+95 −68

Original line number	Diff line number	Diff line
		@@ -254,13 +254,13 @@ static bool ReadDescriptors(std::map<std::string, CgroupDescriptor>* descriptors
		// To avoid issues in sdk_mac build
		#if defined(__ANDROID__)

		static bool SetupCgroup(const CgroupDescriptor& descriptor) {
		static bool IsOptionalController(const format::CgroupController* controller) {
		return controller->flags() & CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
		}

		static bool MountV2CgroupController(const CgroupDescriptor& descriptor) {
		const format::CgroupController* controller = descriptor.controller();

		int result;
		if (controller->version() == 2) {
		result = 0;
		if (!strcmp(controller->name(), CGROUPV2_CONTROLLER_NAME)) {
		// /sys/fs/cgroup is created by cgroup2 with specific selinux permissions,
		// try to create again in case the mount point is changed
		if (!Mkdir(controller->path(), 0, "", "")) {
		@@ -278,32 +278,50 @@ static bool SetupCgroup(const CgroupDescriptor& descriptor) {
		if (mount("none", controller->path(), "cgroup2", MS_NODEV \| MS_NOEXEC \| MS_NOSUID,
		nullptr) < 0) {
		PLOG(ERROR) << "Failed to mount cgroup v2";
		return IsOptionalController(controller);
		}
		}

		// selinux permissions change after mounting, so it's ok to change mode and owner now
		if (!ChangeDirModeAndOwner(controller->path(), descriptor.mode(), descriptor.uid(),
		descriptor.gid())) {
		LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
		result = -1;
		PLOG(ERROR) << "Change of ownership or mode failed for controller " << controller->name();
		return IsOptionalController(controller);
		}
		} else {

		return true;
		}

		static bool ActivateV2CgroupController(const CgroupDescriptor& descriptor) {
		const format::CgroupController* controller = descriptor.controller();

		if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
		LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
		return false;
		}

		if (controller->flags() & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION) {
		std::string str = std::string("+") + controller->name();
		std::string path = std::string(controller->path()) + "/cgroup.subtree_control";
		std::string str = "+";
		str += controller->name();
		std::string path = controller->path();
		path += "/cgroup.subtree_control";

		if (!base::WriteStringToFile(str, path)) {
		LOG(ERROR) << "Failed to activate controller " << controller->name();
		if (IsOptionalController(controller)) {
		PLOG(INFO) << "Failed to activate optional controller " << controller->name();
		return true;
		}
		PLOG(ERROR) << "Failed to activate controller " << controller->name();
		return false;
		}
		}

		return true;
		}
		} else {

		static bool MountV1CgroupController(const CgroupDescriptor& descriptor) {
		const format::CgroupController* controller = descriptor.controller();

		// mkdir <path> [mode] [owner] [group]
		if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
		LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
		@@ -315,30 +333,39 @@ static bool SetupCgroup(const CgroupDescriptor& descriptor) {
		// to be prepended with controller name. For example this way instead of
		// /dev/cpuset/cpuset.cpus the attribute becomes /dev/cpuset/cpus which is what
		// the system currently expects.
		int res;
		if (!strcmp(controller->name(), "cpuset")) {
		// mount cpuset none /dev/cpuset nodev noexec nosuid
		result = mount("none", controller->path(), controller->name(),
		res = mount("none", controller->path(), controller->name(),
		MS_NODEV \| MS_NOEXEC \| MS_NOSUID, nullptr);
		} else {
		// mount cgroup none <path> nodev noexec nosuid <controller>
		result = mount("none", controller->path(), "cgroup", MS_NODEV \| MS_NOEXEC \| MS_NOSUID,
		res = mount("none", controller->path(), "cgroup", MS_NODEV \| MS_NOEXEC \| MS_NOSUID,
		controller->name());
		}
		if (res != 0) {
		if (IsOptionalController(controller)) {
		PLOG(INFO) << "Failed to mount optional controller " << controller->name();
		return true;
		}
		PLOG(ERROR) << "Failed to mount controller " << controller->name();
		return false;
		}
		return true;
		}

		if (result < 0) {
		bool optional = controller->flags() & CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
		static bool SetupCgroup(const CgroupDescriptor& descriptor) {
		const format::CgroupController* controller = descriptor.controller();

		if (optional && errno == EINVAL) {
		// Optional controllers are allowed to fail to mount if kernel does not support them
		LOG(INFO) << "Optional " << controller->name() << " cgroup controller is not mounted";
		if (controller->version() == 2) {
		if (!strcmp(controller->name(), CGROUPV2_CONTROLLER_NAME)) {
		return MountV2CgroupController(descriptor);
		} else {
		PLOG(ERROR) << "Failed to mount " << controller->name() << " cgroup";
		return false;
		return ActivateV2CgroupController(descriptor);
		}
		} else {
		return MountV1CgroupController(descriptor);
		}

		return true;
		}

		#else