1 /* 2 * Copyright (c) 2015-2017 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 29 #ifndef _SYS_WORK_INTERVAL_H 30 #define _SYS_WORK_INTERVAL_H 31 32 #include <stdint.h> 33 #include <sys/cdefs.h> 34 #include <sys/_types/_size_t.h> 35 36 #include <mach/port.h> 37 38 __BEGIN_DECLS 39 40 /* 41 * A work interval is a repeatable unit of work characterized by a 42 * start, finish, and deadline. 43 * 44 * Trusted clients with deadline-sensitive work may report information 45 * about the execution of their work using the work interval facility. 46 * This is intended to be a higher-level semantic than realtime scheduling, 47 * which operates at the level of thread block/unblock. A high level 48 * operation may have many blocking points, including IPC to other tasks, 49 * and this this metric will capture the overall time to complete a unit of 50 * work. 51 * 52 * A work interval is defined by several timestamps, namely (S)tart, 53 * (F)inish, (D)eadline, and (N)ext start. 54 * 55 * ... ----+==================+--------+--+==== ... 56 * | | | | 57 * S F D N 58 * 59 * \__________________/ 60 * Active 61 * \___________________________/ 62 * Work Interval 63 * 64 * \_________/ 65 * | 66 * report information here ---------+ 67 * 68 * Definitions: 69 * 70 * Start: Absolute time when the current deadline-oriented work began. Due 71 * to scheduling latency, preemption, and blocking points, the 72 * thread controlling the work interval may actually begin 73 * executing after this ideal time (which may be the previous work 74 * interval's "next start") 75 * Finish: Absolute time when the current deadline-oriented work finished. 76 * This will typically be a timestamp taken before reporting using 77 * the work interval interface. 78 * Deadline: Absolute time by which the current work was expected to finish. 79 * In cases where the amount of computation (or preemption, or time 80 * spent blocked) causes the active period to take longer than 81 * expected, F may be greater than D. 82 * Next start: Absolute time when the next deadline-oriented work is 83 * expected to begin. This is typically the same as Deadline. 84 * Active: The fraction of the work interval spent completing the work. In 85 * cases where the Finish time exceeded the Deadline, this fraction 86 * will be >1.0. 87 * 88 * Basic Use: 89 * 90 * Clients should report information for a work interval after finishing 91 * work for the current interval but before the next work interval begins. 92 * 93 * If Finish far exceeds the previously expected Deadline, the 94 * caller may adjust Next Start to align to a multiple of the period 95 * (and skip over several work intervals that could not be 96 * executed). 97 * 98 * Caution (!): 99 * 100 * Because the information supplied via this facility directly influences power 101 * management decisions, clients should strive to be as accurate as possible. 102 * Failure to do so will adversely impact system power and performance. 103 * 104 * Work Interval Auto Join Support: 105 * 106 * Work intervals support an optional flag WORK_INTERVAL_FLAG_ENABLE_AUTO_JOIN 107 * which allows RT threads from the same home thread group to join work 108 * intervals via wakeup relationship tracking. Based on the join policy, 109 * RT threads can temporarily join the work interval of other RT threads 110 * which make them runnable. The auto joined thread remains in the work 111 * interval until it blocks or terminates. The mechanism works through 112 * make runnable heuristic and it should be used with extreme caution. 113 * If a client specifies this flag, it gives up explicit control over its 114 * thread group membership and threads unrelated to the work interval 115 * could become part of the thread group. This could lead to serious power 116 * and performance issues. If the make runnable heuristic does not work 117 * for a client use case, it should adopt work_interval_join_port() or 118 * work_interval_join() to explicitly declare its intent. 119 * 120 * Work Interval Deferred Finish Support: 121 * 122 * Another advanced feature for work intervals is the ability to defer the finish 123 * calls for the work interval until all auto-joined threads for the work interval 124 * have blocked or terminated. This feature is enabled via an optional flag 125 * WORK_INTERVAL_FLAG_ENABLE_DEFERRED_FINISH and is valid only if the work interval 126 * is configured with the WORK_INTERVAL_FLAG_ENABLE_AUTO_JOIN flag as well. The 127 * deferred finish mechanism allows the work interval to defer the finish call 128 * for the work interval until all auto-join threads have blocked/terminated 129 * (and have therefore un-joined the work interval) or one of the work interval 130 * threads calls start for the next frame. The deferred finish works only for 131 * workloads that have no temporal overlap across frames i.e. previous frame has to 132 * finish before next frame can start. This feature should be used with caution 133 * since auto-joined threads would delay finish calls to the performance controller 134 * which could lead to poor performance and battery life. 135 */ 136 137 /* Flags to be passed with work_interval_create() */ 138 139 /* If interval is joinable, create no longer implicitly joins, you must use work_interval_join */ 140 #define WORK_INTERVAL_FLAG_JOINABLE (0x1) 141 /* Only threads that join the group are measured together, otherwise the group is the creator's home group */ 142 #define WORK_INTERVAL_FLAG_GROUP (0x2) 143 /* Specifies that the work interval is being created by a client who doesn't 144 * necessarily have the PRIV_WORK_INTERVAL entitlement. Skip privilege checks. 145 * This can only be masked in for work intervals of types COREAUDIO, CA_CLIENT 146 * and DEFAULT */ 147 #define WORK_INTERVAL_FLAG_UNRESTRICTED (0x4) 148 149 /* [Advanced Flag] Read section on "Work Interval Auto Join Support" above for details */ 150 #define WORK_INTERVAL_FLAG_ENABLE_AUTO_JOIN (0x8) 151 /* [Advanced Flag] Read section on "Work Interval Deferred Finish Support" above for details */ 152 #define WORK_INTERVAL_FLAG_ENABLE_DEFERRED_FINISH (0x10) 153 154 /* Kernel-supplied flag: Work interval has been ignored by the kernel */ 155 #define WORK_INTERVAL_FLAG_IGNORED (0x20) 156 157 /* Specifies that the work interval requests the system to provide just enough performance 158 * to be able to finish at the provided deadline and no sooner. */ 159 #define WORK_INTERVAL_FLAG_FINISH_AT_DEADLINE (0x40) 160 161 /* Internal-only flag: workinterval will have the SET_WORKLOAD_ID operation called on it immediately 162 * after creation. */ 163 #define WORK_INTERVAL_FLAG_HAS_WORKLOAD_ID (0x80) 164 165 /* Flags to describe the interval flavor to the performance controller */ 166 #define WORK_INTERVAL_TYPE_MASK (0xF0000000) 167 #define WORK_INTERVAL_TYPE_DEFAULT (0x0 << 28) 168 #define WORK_INTERVAL_TYPE_COREAUDIO (0x1 << 28) 169 #define WORK_INTERVAL_TYPE_COREANIMATION (0x2 << 28) 170 #define WORK_INTERVAL_TYPE_CA_RENDER_SERVER (0x2 << 28) 171 #define WORK_INTERVAL_TYPE_CA_CLIENT (0x3 << 28) 172 #define WORK_INTERVAL_TYPE_HID_DELIVERY (0x4 << 28) 173 #define WORK_INTERVAL_TYPE_COREMEDIA (0x5 << 28) 174 #define WORK_INTERVAL_TYPE_ARKIT (0x6 << 28) 175 #define WORK_INTERVAL_TYPE_FRAME_COMPOSITOR (0x7 << 28) 176 #define WORK_INTERVAL_TYPE_LAST (0xF << 28) 177 178 #ifndef KERNEL 179 180 typedef struct work_interval *work_interval_t; 181 typedef struct work_interval_instance *work_interval_instance_t; 182 183 /* 184 * Create a new work interval handle. 185 * 186 * May fail with EALREADY if the current group already has a work interval. 187 * 188 * With no flags: 189 * Auto-joins the work interval to the creating thread 190 * May only use interval_handle from creating thread 191 * Data provided affects native thread group 192 * 193 * With the JOINABLE flag 194 * interval_handle is usable by the process 195 * creating thread does not auto-join 196 * notifying thread must have joined when notifying 197 * 198 * With the GROUP flag 199 * creates a new thread group to isolate the joined threads from 200 * the rest of the process for performance controller analysis 201 * Threads which join the work interval become members of this new group 202 * 203 * TODO: Add a name parameter so that clients can name the work interval 204 * Can also take the thread name from the notifying thread 205 * 206 * Requires the 'com.apple.private.kernel.work-interval' entitlement (PRIV_WORK_INTERVAL) 207 * 208 * Note that joining a work interval supersedes automatic thread group management via vouchers 209 */ 210 int work_interval_create(work_interval_t *interval_handle, uint32_t flags); 211 212 /* Returns the flags used for the work interval when it was created. 213 * 214 * May fail with EINVAL if the port isn't from a prior call to 215 * work_interval_copy_port. 216 */ 217 int work_interval_get_flags_from_port(mach_port_t port, uint32_t *flags); 218 219 220 /* 221 * Notify the power management subsystem that the work for a current interval has completed 222 * 223 * Only the process which created the work interval may notify 224 */ 225 int work_interval_notify(work_interval_t interval_handle, 226 uint64_t start, uint64_t finish, 227 uint64_t deadline, uint64_t next_start, 228 uint32_t flags); 229 230 /* 231 * Notify, with "finish" implicitly set to the current time 232 * 233 * Only the process which created the work interval may notify 234 */ 235 int work_interval_notify_simple(work_interval_t interval_handle, 236 uint64_t start, uint64_t deadline, 237 uint64_t next_start); 238 239 /* 240 * Deallocate work interval handle 241 * For non-JOINABLE, also removes thread from work interval 242 * For JOINABLE, does not remove thread (needs a leave as well) 243 */ 244 int work_interval_destroy(work_interval_t interval_handle); 245 246 /* 247 * Join work interval via work interval handle 248 * Only allowed if interval is using the joinable and group flags 249 * 250 * Supersedes automatic thread group management via vouchers 251 */ 252 int work_interval_join(work_interval_t interval_handle); 253 254 /* 255 * extract Mach send right representing work interval thread group 256 * Returns a +1 send right ref, which must be deallocated via mach_port_deallocate 257 * Only allowed if interval is joinable, otherwise returns ENOTSUP 258 * 259 * Supersedes automatic thread group management via vouchers 260 */ 261 int work_interval_copy_port(work_interval_t interval_handle, mach_port_t *port); 262 263 /* 264 * Join work interval via Mach send right 265 * 266 * Does NOT consume Mach send right, must deallocate with mach_port_deallocate after using 267 * It's safe to deallocate the right after joining, the thread will stay joined 268 * 269 * Can be sent to clients via xpc_dictionary_copy_mach_send, and similar 270 * 271 * Supersedes automatic thread group management via vouchers 272 * 273 * If the underlying work interval object is terminated then this may return ENOENT 274 * <rdar://problem/31819320> 275 */ 276 int work_interval_join_port(mach_port_t port); 277 278 /* 279 * Leave the current thread's work interval 280 */ 281 int work_interval_leave(void); 282 283 #endif /* !KERNEL */ 284 285 #if PRIVATE 286 287 /* Private interface between Libsyscall and xnu */ 288 #define WORK_INTERVAL_OPERATION_CREATE 0x00000001 /* deprecated */ 289 #define WORK_INTERVAL_OPERATION_DESTROY 0x00000002 /* arg is NULL */ 290 #define WORK_INTERVAL_OPERATION_NOTIFY 0x00000003 /* arg is a work_interval_notification_t */ 291 #define WORK_INTERVAL_OPERATION_CREATE2 0x00000004 /* arg is a work_interval_create_params */ 292 #define WORK_INTERVAL_OPERATION_JOIN 0x00000005 /* arg is a port_name */ 293 #define WORK_INTERVAL_OPERATION_GET_FLAGS 0x00000009 /* arg is a port name */ 294 #define WORK_INTERVAL_OPERATION_SET_NAME 0x0000000a /* arg is name string (char[WORK_INTERVAL_NAME_MAX])*/ 295 #define WORK_INTERVAL_OPERATION_SET_WORKLOAD_ID 0x0000000b /* arg is a work_interval_workload_id_params */ 296 297 #define WORK_INTERVAL_NAME_MAX 32 298 #define WORK_INTERVAL_WORKLOAD_ID_NAME_MAX 64 299 300 /* Flags passed in work_interval_workload_id_params wlidp_flags field */ 301 #define WORK_INTERVAL_WORKLOAD_ID_HAS_ID (1u << 0) 302 #define WORK_INTERVAL_WORKLOAD_ID_RT_ALLOWED (1u << 1) 303 #define WORK_INTERVAL_WORKLOAD_ID_RT_CRITICAL (1u << 2) 304 305 /* Flags allowed to be passed in from userspace as part of kern_work_interval_set_workload_id() */ 306 #define WORK_INTERVAL_SET_WORKLOAD_ID_FLAGS_MASK (WORK_INTERVAL_WORKLOAD_ID_RT_CRITICAL | WORK_INTERVAL_WORKLOAD_ID_RT_ALLOWED) 307 308 #ifdef XNU_KERNEL_PRIVATE 309 310 /* Marker that workinterval was joined before workload ID was set */ 311 #define WORK_INTERVAL_WORKLOAD_ID_ALREADY_JOINED (1u << 31) 312 /* Work interval is allowed to provide complexity values per frame as part of {start, update, finish} calls */ 313 #define WORK_INTERVAL_WORKLOAD_ID_COMPLEXITY_ALLOWED (1u << 30) 314 315 #endif /* XNU_KERNEL_PRIVATE */ 316 317 struct work_interval_notification { 318 uint64_t start; 319 uint64_t finish; 320 uint64_t deadline; 321 uint64_t next_start; 322 uint32_t notify_flags; 323 uint32_t create_flags; 324 }; 325 typedef struct work_interval_notification *work_interval_notification_t; 326 327 struct work_interval_create_params { 328 uint64_t wicp_id; /* in/out param */ 329 mach_port_name_t wicp_port; /* in/out param */ 330 uint32_t wicp_create_flags; 331 }; 332 333 struct work_interval_workload_id_params { 334 uint32_t wlidp_flags; /* in/out param */ 335 uint32_t wlidp_wicreate_flags; /* in/out param */ 336 uint64_t wlidp_name; /* in param (pointer to char[WORK_INTERVAL_WORKLOAD_ID_NAME_MAX])*/ 337 uint64_t wlidp_syscall_mask[2]; /* out param (needs to fit MACH_TRAP_TABLE_COUNT + nsysent bits) */ 338 }; 339 340 341 int __work_interval_ctl(uint32_t operation, uint64_t work_interval_id, void *arg, size_t len); 342 343 #endif /* PRIVATE */ 344 345 __END_DECLS 346 347 #endif /* _SYS_WORK_INTERVAL_H */ 348