Suren Baghdasaryan | a92de71 | 2018-03-07 12:27:50 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2018 Google, Inc |
| 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 | #ifndef _LMKD_H_ |
| 18 | #define _LMKD_H_ |
| 19 | |
| 20 | #include <arpa/inet.h> |
| 21 | #include <sys/cdefs.h> |
| 22 | #include <sys/types.h> |
| 23 | |
| 24 | __BEGIN_DECLS |
| 25 | |
| 26 | /* |
| 27 | * Supported LMKD commands |
| 28 | */ |
| 29 | enum lmk_cmd { |
| 30 | LMK_TARGET = 0, /* Associate minfree with oom_adj_score */ |
| 31 | LMK_PROCPRIO, /* Register a process and set its oom_adj_score */ |
| 32 | LMK_PROCREMOVE, /* Unregister a process */ |
Suren Baghdasaryan | e3b6047 | 2018-10-10 14:17:17 -0700 | [diff] [blame] | 33 | LMK_PROCPURGE, /* Purge all registered processes */ |
Suren Baghdasaryan | a92de71 | 2018-03-07 12:27:50 -0800 | [diff] [blame] | 34 | }; |
| 35 | |
| 36 | /* |
| 37 | * Max number of targets in LMK_TARGET command. |
| 38 | */ |
| 39 | #define MAX_TARGETS 6 |
| 40 | |
| 41 | /* |
| 42 | * Max packet length in bytes. |
| 43 | * Longest packet is LMK_TARGET followed by MAX_TARGETS |
| 44 | * of minfree and oom_adj_score values |
| 45 | */ |
| 46 | #define CTRL_PACKET_MAX_SIZE (sizeof(int) * (MAX_TARGETS * 2 + 1)) |
| 47 | |
| 48 | /* LMKD packet - first int is lmk_cmd followed by payload */ |
| 49 | typedef int LMKD_CTRL_PACKET[CTRL_PACKET_MAX_SIZE / sizeof(int)]; |
| 50 | |
| 51 | /* Get LMKD packet command */ |
| 52 | inline enum lmk_cmd lmkd_pack_get_cmd(LMKD_CTRL_PACKET pack) { |
| 53 | return (enum lmk_cmd)ntohl(pack[0]); |
| 54 | } |
| 55 | |
| 56 | /* LMK_TARGET packet payload */ |
| 57 | struct lmk_target { |
| 58 | int minfree; |
| 59 | int oom_adj_score; |
| 60 | }; |
| 61 | |
| 62 | /* |
| 63 | * For LMK_TARGET packet get target_idx-th payload. |
| 64 | * Warning: no checks performed, caller should ensure valid parameters. |
| 65 | */ |
| 66 | inline void lmkd_pack_get_target(LMKD_CTRL_PACKET packet, |
| 67 | int target_idx, struct lmk_target *target) { |
| 68 | target->minfree = ntohl(packet[target_idx * 2 + 1]); |
| 69 | target->oom_adj_score = ntohl(packet[target_idx * 2 + 2]); |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * Prepare LMK_TARGET packet and return packet size in bytes. |
| 74 | * Warning: no checks performed, caller should ensure valid parameters. |
| 75 | */ |
| 76 | inline size_t lmkd_pack_set_target(LMKD_CTRL_PACKET packet, |
| 77 | struct lmk_target *targets, |
| 78 | size_t target_cnt) { |
| 79 | int idx = 0; |
| 80 | packet[idx++] = htonl(LMK_TARGET); |
| 81 | while (target_cnt) { |
| 82 | packet[idx++] = htonl(targets->minfree); |
| 83 | packet[idx++] = htonl(targets->oom_adj_score); |
| 84 | targets++; |
| 85 | target_cnt--; |
| 86 | } |
| 87 | return idx * sizeof(int); |
| 88 | } |
| 89 | |
| 90 | /* LMK_PROCPRIO packet payload */ |
| 91 | struct lmk_procprio { |
| 92 | pid_t pid; |
| 93 | uid_t uid; |
| 94 | int oomadj; |
| 95 | }; |
| 96 | |
| 97 | /* |
| 98 | * For LMK_PROCPRIO packet get its payload. |
| 99 | * Warning: no checks performed, caller should ensure valid parameters. |
| 100 | */ |
| 101 | inline void lmkd_pack_get_procprio(LMKD_CTRL_PACKET packet, |
| 102 | struct lmk_procprio *params) { |
| 103 | params->pid = (pid_t)ntohl(packet[1]); |
| 104 | params->uid = (uid_t)ntohl(packet[2]); |
| 105 | params->oomadj = ntohl(packet[3]); |
| 106 | } |
| 107 | |
| 108 | /* |
| 109 | * Prepare LMK_PROCPRIO packet and return packet size in bytes. |
| 110 | * Warning: no checks performed, caller should ensure valid parameters. |
| 111 | */ |
| 112 | inline size_t lmkd_pack_set_procprio(LMKD_CTRL_PACKET packet, |
| 113 | struct lmk_procprio *params) { |
| 114 | packet[0] = htonl(LMK_PROCPRIO); |
| 115 | packet[1] = htonl(params->pid); |
| 116 | packet[2] = htonl(params->uid); |
| 117 | packet[3] = htonl(params->oomadj); |
| 118 | return 4 * sizeof(int); |
| 119 | } |
| 120 | |
| 121 | /* LMK_PROCREMOVE packet payload */ |
| 122 | struct lmk_procremove { |
| 123 | pid_t pid; |
| 124 | }; |
| 125 | |
| 126 | /* |
| 127 | * For LMK_PROCREMOVE packet get its payload. |
| 128 | * Warning: no checks performed, caller should ensure valid parameters. |
| 129 | */ |
| 130 | inline void lmkd_pack_get_procremove(LMKD_CTRL_PACKET packet, |
| 131 | struct lmk_procremove *params) { |
| 132 | params->pid = (pid_t)ntohl(packet[1]); |
| 133 | } |
| 134 | |
| 135 | /* |
| 136 | * Prepare LMK_PROCREMOVE packet and return packet size in bytes. |
| 137 | * Warning: no checks performed, caller should ensure valid parameters. |
| 138 | */ |
| 139 | inline size_t lmkd_pack_set_procremove(LMKD_CTRL_PACKET packet, |
| 140 | struct lmk_procprio *params) { |
| 141 | packet[0] = htonl(LMK_PROCREMOVE); |
| 142 | packet[1] = htonl(params->pid); |
| 143 | return 2 * sizeof(int); |
| 144 | } |
| 145 | |
Suren Baghdasaryan | e3b6047 | 2018-10-10 14:17:17 -0700 | [diff] [blame] | 146 | /* |
| 147 | * Prepare LMK_PROCPURGE packet and return packet size in bytes. |
| 148 | * Warning: no checks performed, caller should ensure valid parameters. |
| 149 | */ |
| 150 | inline size_t lmkd_pack_set_procpurge(LMKD_CTRL_PACKET packet) { |
| 151 | packet[0] = htonl(LMK_PROCPURGE); |
| 152 | return sizeof(int); |
| 153 | } |
| 154 | |
Suren Baghdasaryan | a92de71 | 2018-03-07 12:27:50 -0800 | [diff] [blame] | 155 | __END_DECLS |
| 156 | |
| 157 | #endif /* _LMKD_H_ */ |