Suren Baghdasaryan | c29c2ba | 2019-10-22 17:18:42 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2019 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include "lmkd_service.h" |
| 18 | |
| 19 | #include <errno.h> |
| 20 | |
| 21 | #include <android-base/logging.h> |
| 22 | #include <liblmkd_utils.h> |
| 23 | |
| 24 | #include "service_list.h" |
| 25 | |
| 26 | namespace android { |
| 27 | namespace init { |
| 28 | |
| 29 | enum LmkdRegistrationResult { |
| 30 | LMKD_REG_SUCCESS, |
| 31 | LMKD_CONN_FAILED, |
| 32 | LMKD_REG_FAILED, |
| 33 | }; |
| 34 | |
| 35 | static int lmkd_socket = -1; |
| 36 | |
| 37 | static LmkdRegistrationResult RegisterProcess(uid_t uid, pid_t pid, int oom_score_adjust) { |
| 38 | // connect to lmkd if not already connected |
| 39 | if (lmkd_socket < 0) { |
| 40 | lmkd_socket = lmkd_connect(); |
| 41 | if (lmkd_socket < 0) { |
| 42 | return LMKD_CONN_FAILED; |
| 43 | } |
| 44 | } |
| 45 | |
| 46 | // register service with lmkd |
| 47 | struct lmk_procprio params; |
| 48 | params.pid = pid; |
| 49 | params.uid = uid; |
| 50 | params.oomadj = oom_score_adjust; |
| 51 | params.ptype = PROC_TYPE_SERVICE; |
| 52 | if (lmkd_register_proc(lmkd_socket, ¶ms) != 0) { |
| 53 | // data transfer failed, reset the connection |
| 54 | close(lmkd_socket); |
| 55 | lmkd_socket = -1; |
| 56 | return LMKD_REG_FAILED; |
| 57 | } |
| 58 | |
| 59 | return LMKD_REG_SUCCESS; |
| 60 | } |
| 61 | |
| 62 | static bool UnregisterProcess(pid_t pid) { |
| 63 | if (lmkd_socket < 0) { |
| 64 | // no connection or it was lost, no need to unregister |
| 65 | return false; |
| 66 | } |
| 67 | |
| 68 | // unregister service |
| 69 | struct lmk_procremove params; |
| 70 | params.pid = pid; |
| 71 | if (lmkd_unregister_proc(lmkd_socket, ¶ms) != 0) { |
| 72 | // data transfer failed, reset the connection |
| 73 | close(lmkd_socket); |
| 74 | lmkd_socket = -1; |
| 75 | return false; |
| 76 | } |
| 77 | |
| 78 | return true; |
| 79 | } |
| 80 | |
| 81 | static void RegisterServices(pid_t exclude_pid) { |
Nikita Ioffe | 8d6ae2d | 2020-11-27 18:57:44 +0000 | [diff] [blame] | 82 | for (const auto& service : ServiceList::GetInstance()) { |
Suren Baghdasaryan | c29c2ba | 2019-10-22 17:18:42 -0700 | [diff] [blame] | 83 | auto svc = service.get(); |
| 84 | if (svc->oom_score_adjust() != DEFAULT_OOM_SCORE_ADJUST) { |
| 85 | // skip if process is excluded or not yet forked (pid==0) |
| 86 | if (svc->pid() == exclude_pid || svc->pid() == 0) { |
| 87 | continue; |
| 88 | } |
| 89 | if (RegisterProcess(svc->uid(), svc->pid(), svc->oom_score_adjust()) != |
| 90 | LMKD_REG_SUCCESS) { |
| 91 | // a failure here resets the connection, will retry during next registration |
| 92 | break; |
| 93 | } |
| 94 | } |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | void LmkdRegister(const std::string& name, uid_t uid, pid_t pid, int oom_score_adjust) { |
| 99 | bool new_connection = lmkd_socket == -1; |
| 100 | LmkdRegistrationResult result; |
| 101 | |
| 102 | result = RegisterProcess(uid, pid, oom_score_adjust); |
| 103 | if (result == LMKD_REG_FAILED) { |
| 104 | // retry one time if connection to lmkd was lost |
| 105 | result = RegisterProcess(uid, pid, oom_score_adjust); |
| 106 | new_connection = result == LMKD_REG_SUCCESS; |
| 107 | } |
| 108 | switch (result) { |
| 109 | case LMKD_REG_SUCCESS: |
| 110 | // register existing services once new connection is established |
| 111 | if (new_connection) { |
| 112 | RegisterServices(pid); |
| 113 | } |
| 114 | break; |
| 115 | case LMKD_CONN_FAILED: |
| 116 | PLOG(ERROR) << "lmkd connection failed when " << name << " process got started"; |
| 117 | break; |
| 118 | case LMKD_REG_FAILED: |
| 119 | PLOG(ERROR) << "lmkd failed to register " << name << " process"; |
| 120 | break; |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | void LmkdUnregister(const std::string& name, pid_t pid) { |
| 125 | if (!UnregisterProcess(pid)) { |
| 126 | PLOG(ERROR) << "lmkd failed to unregister " << name << " process"; |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | } // namespace init |
| 131 | } // namespace android |