| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "lmkd_service.h" |
| |
| #include <errno.h> |
| |
| #include <android-base/logging.h> |
| #include <liblmkd_utils.h> |
| |
| #include "service_list.h" |
| |
| namespace android { |
| namespace init { |
| |
| enum LmkdRegistrationResult { |
| LMKD_REG_SUCCESS, |
| LMKD_CONN_FAILED, |
| LMKD_REG_FAILED, |
| }; |
| |
| static int lmkd_socket = -1; |
| |
| static LmkdRegistrationResult RegisterProcess(uid_t uid, pid_t pid, int oom_score_adjust) { |
| // connect to lmkd if not already connected |
| if (lmkd_socket < 0) { |
| lmkd_socket = lmkd_connect(); |
| if (lmkd_socket < 0) { |
| return LMKD_CONN_FAILED; |
| } |
| } |
| |
| // register service with lmkd |
| struct lmk_procprio params; |
| params.pid = pid; |
| params.uid = uid; |
| params.oomadj = oom_score_adjust; |
| params.ptype = PROC_TYPE_SERVICE; |
| if (lmkd_register_proc(lmkd_socket, ¶ms) != 0) { |
| // data transfer failed, reset the connection |
| close(lmkd_socket); |
| lmkd_socket = -1; |
| return LMKD_REG_FAILED; |
| } |
| |
| return LMKD_REG_SUCCESS; |
| } |
| |
| static bool UnregisterProcess(pid_t pid) { |
| if (lmkd_socket < 0) { |
| // no connection or it was lost, no need to unregister |
| return false; |
| } |
| |
| // unregister service |
| struct lmk_procremove params; |
| params.pid = pid; |
| if (lmkd_unregister_proc(lmkd_socket, ¶ms) != 0) { |
| // data transfer failed, reset the connection |
| close(lmkd_socket); |
| lmkd_socket = -1; |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static void RegisterServices(pid_t exclude_pid) { |
| for (const auto& service : ServiceList::GetInstance().services()) { |
| auto svc = service.get(); |
| if (svc->oom_score_adjust() != DEFAULT_OOM_SCORE_ADJUST) { |
| // skip if process is excluded or not yet forked (pid==0) |
| if (svc->pid() == exclude_pid || svc->pid() == 0) { |
| continue; |
| } |
| if (RegisterProcess(svc->uid(), svc->pid(), svc->oom_score_adjust()) != |
| LMKD_REG_SUCCESS) { |
| // a failure here resets the connection, will retry during next registration |
| break; |
| } |
| } |
| } |
| } |
| |
| void LmkdRegister(const std::string& name, uid_t uid, pid_t pid, int oom_score_adjust) { |
| bool new_connection = lmkd_socket == -1; |
| LmkdRegistrationResult result; |
| |
| result = RegisterProcess(uid, pid, oom_score_adjust); |
| if (result == LMKD_REG_FAILED) { |
| // retry one time if connection to lmkd was lost |
| result = RegisterProcess(uid, pid, oom_score_adjust); |
| new_connection = result == LMKD_REG_SUCCESS; |
| } |
| switch (result) { |
| case LMKD_REG_SUCCESS: |
| // register existing services once new connection is established |
| if (new_connection) { |
| RegisterServices(pid); |
| } |
| break; |
| case LMKD_CONN_FAILED: |
| PLOG(ERROR) << "lmkd connection failed when " << name << " process got started"; |
| break; |
| case LMKD_REG_FAILED: |
| PLOG(ERROR) << "lmkd failed to register " << name << " process"; |
| break; |
| } |
| } |
| |
| void LmkdUnregister(const std::string& name, pid_t pid) { |
| if (!UnregisterProcess(pid)) { |
| PLOG(ERROR) << "lmkd failed to unregister " << name << " process"; |
| } |
| } |
| |
| } // namespace init |
| } // namespace android |