1/* 2 * Copyright (c) 1993-1995, 1999-2008 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/*! 30 @header thread_call.h 31 @discussion Facilities for executing work asynchronously. 32 */ 33 34#ifndef _KERN_THREAD_CALL_H_ 35#define _KERN_THREAD_CALL_H_ 36 37#include <mach/mach_types.h> 38 39#include <kern/clock.h> 40 41#include <sys/cdefs.h> 42 43struct thread_call; 44typedef struct thread_call *thread_call_t; 45 46typedef void *thread_call_param_t; 47typedef void (*thread_call_func_t)( 48 thread_call_param_t param0, 49 thread_call_param_t param1); 50/*! 51 @enum thread_call_priority_t 52 @discussion Thread call priorities should not be assumed to have any specific 53 numerical value; they should be interpreted as importances or roles for work 54 items, priorities for which will be reasonably managed by the subsystem. 55 @constant THREAD_CALL_PRIORITY_HIGH Importance above everything but realtime. 56 Thread calls allocated with this priority execute at extremely high priority, 57 above everything but realtime threads. They are generally executed in serial. 58 Though they may execute concurrently under some circumstances, no fan-out is implied. 59 These work items should do very small amounts of work or risk disrupting system 60 responsiveness. 61 @constant THREAD_CALL_PRIORITY_KERNEL Importance similar to that of normal kernel 62 threads. 63 @constant THREAD_CALL_PRIORITY_USER Importance similar to that of normal user threads. 64 @constant THREAD_CALL_PRIORITY_LOW Very low importance. 65 */ 66typedef enum { 67 THREAD_CALL_PRIORITY_HIGH = 0, 68 THREAD_CALL_PRIORITY_KERNEL = 1, 69 THREAD_CALL_PRIORITY_USER = 2, 70 THREAD_CALL_PRIORITY_LOW = 3 71} thread_call_priority_t; 72 73__BEGIN_DECLS 74 75/*! 76 @function thread_call_enter 77 @abstract Submit a thread call work item for immediate execution. 78 @discussion If the work item is already scheduled for delayed execution, and it has 79 not yet begun to run, that delayed invocation will be cancelled. Note that if a 80 thread call is rescheduled from its own callback, then multiple invocations of the 81 callback may be in flight at the same time. 82 @result TRUE if the call was already pending for either delayed or immediate 83 execution, FALSE otherwise. 84 @param call The thread call to execute. 85 */ 86extern boolean_t thread_call_enter( 87 thread_call_t call); 88/*! 89 @function thread_call_enter1 90 @abstract Submit a thread call work item for immediate execution, with an extra parameter. 91 @discussion This routine is identical to thread_call_enter(), except that 92 the second parameter to the callback is specified. 93 @result TRUE if the call was already pending for either delayed or immediate 94 execution, FALSE otherwise. 95 @param call The thread call to execute. 96 @param param1 Parameter to pass callback. 97 */ 98extern boolean_t thread_call_enter1( 99 thread_call_t call, 100 thread_call_param_t param1); 101 102/*! 103 @function thread_call_enter_delayed 104 @abstract Submit a thread call to be executed at some point in the future. 105 @discussion If the work item is already scheduled for delayed or immediate execution, 106 and it has not yet begun to run, that invocation will be cancelled in favor of execution 107 at the newly specified time. Note that if a thread call is rescheduled from its own callback, 108 then multiple invocations of the callback may be in flight at the same time. 109 @result TRUE if the call was already pending for either delayed or immediate 110 execution, FALSE otherwise. 111 @param call The thread call to execute. 112 @param deadline Time, in absolute time units, at which to execute callback. 113 */ 114extern boolean_t thread_call_enter_delayed( 115 thread_call_t call, 116 uint64_t deadline); 117/*! 118 @function thread_call_enter1_delayed 119 @abstract Submit a thread call to be executed at some point in the future, with an extra parameter. 120 @discussion This routine is identical to thread_call_enter_delayed(), 121 except that a second parameter to the callback is specified. 122 @result TRUE if the call was already pending for either delayed or immediate 123 execution, FALSE otherwise. 124 @param call The thread call to execute. 125 @param param1 Second parameter to callback. 126 @param deadline Time, in absolute time units, at which to execute callback. 127 */ 128extern boolean_t thread_call_enter1_delayed( 129 thread_call_t call, 130 thread_call_param_t param1, 131 uint64_t deadline); 132 133/*! 134 @function thread_call_cancel 135 @abstract Attempt to cancel a pending invocation of a thread call. 136 @discussion Attempt to cancel a thread call which has been scheduled 137 for execution with a thread_call_enter* variant. If the call has not 138 yet begun executing, the pending invocation will be cancelled and TRUE 139 will be returned. If the work item has already begun executing, 140 thread_call_cancel will return FALSE immediately; the callback may be 141 about to run, currently running, or already done executing. 142 @result TRUE if the call was successfully cancelled, FALSE otherwise. 143 */ 144extern boolean_t thread_call_cancel( 145 thread_call_t call); 146/*! 147 @function thread_call_cancel_wait 148 @abstract Attempt to cancel a pending invocation of a thread call. 149 If unable to cancel, wait for current invocation to finish. 150 @discussion Attempt to cancel a thread call which has been scheduled 151 for execution with a thread_call_enter* variant. If the call has not 152 yet begun executing, the pending invocation will be cancelled and TRUE 153 will be returned. If the work item has already begun executing, 154 thread_call_cancel_wait waits for the most recent invocation to finish. When 155 called on a work item which has already finished, it will return FALSE immediately. 156 Note that this routine can only be used on thread calls set up with either 157 thread_call_allocate or thread_call_allocate_with_priority, and that invocations 158 of the thread call <i>after</i> the current invocation may be in flight when 159 thread_call_cancel_wait returns. 160 @result TRUE if the call was successfully cancelled, FALSE otherwise. 161 */ 162extern boolean_t thread_call_cancel_wait( 163 thread_call_t call); 164 165 /*! 166 @function thread_call_allocate 167 @abstract Allocate a thread call to execute with default (high) priority. 168 @discussion Allocates a thread call that will run with properties of 169 THREAD_CALL_PRIORITY_HIGH, binding the first parameter to the callback. 170 @param func Callback to invoke when thread call is scheduled. 171 @param param0 First argument ot pass to callback. 172 @result Thread call which can be passed to thread_call_enter variants. 173 */ 174extern thread_call_t thread_call_allocate( 175 thread_call_func_t func, 176 thread_call_param_t param0); 177 178 /*! 179 @function thread_call_allocate_with_priority 180 @abstract Allocate a thread call to execute with a specified priority. 181 @discussion Identical to thread_call_allocate, except that priority 182 is specified by caller. 183 @param func Callback to invoke when thread call is scheduled. 184 @param param0 First argument to pass to callback. 185 @param pri Priority of item. 186 @result Thread call which can be passed to thread_call_enter variants. 187 */ 188extern thread_call_t thread_call_allocate_with_priority( 189 thread_call_func_t func, 190 thread_call_param_t param0, 191 thread_call_priority_t pri); 192 193/*! 194 @function thread_call_free 195 @abstract Release a thread call. 196 @discussion Should only be used on thread calls allocated with thread_call_allocate 197 or thread_call_allocate_with_priority. Once thread_call_free has been called, 198 no other operations may be performed on a thread call. If the thread call is 199 currently pending, thread_call_free will return FALSE and will have no effect. 200 Calling thread_call_free from a thread call's own callback is safe; the work 201 item is not considering "pending" at that point. 202 @result TRUE if the thread call has been successfully released, else FALSE. 203 @param call The thread call to release. 204 */ 205extern boolean_t thread_call_free( 206 thread_call_t call); 207 208/*! 209 @function thread_call_isactive 210 @abstract Determine whether a thread call is pending or currently executing. 211 @param call Thread call to examine. 212 @result TRUE if the thread call is either scheduled for execution (immediately 213 or at some point in the future) or is currently executing. 214 */ 215boolean_t thread_call_isactive( 216 thread_call_t call); 217__END_DECLS 218 219#ifdef MACH_KERNEL_PRIVATE 220 221#include <kern/call_entry.h> 222 223struct thread_call { 224 struct call_entry tc_call; /* Must be first */ 225 uint64_t tc_submit_count; 226 uint64_t tc_finish_count; 227 thread_call_priority_t tc_pri; 228 229 uint32_t tc_flags; 230 int32_t tc_refs; 231 232 uint64_t ttd; /* Time to deadline at creation */ 233}; 234 235#define THREAD_CALL_ALLOC 0x01 236#define THREAD_CALL_WAIT 0x02 237 238typedef struct thread_call thread_call_data_t; 239 240extern void thread_call_initialize(void); 241 242extern void thread_call_setup( 243 thread_call_t call, 244 thread_call_func_t func, 245 thread_call_param_t param0); 246 247#endif /* MACH_KERNEL_PRIVATE */ 248 249#ifdef KERNEL_PRIVATE 250 251__BEGIN_DECLS 252 253/* 254 * Obsolete interfaces. 255 */ 256 257#ifndef __LP64__ 258 259extern boolean_t thread_call_is_delayed( 260 thread_call_t call, 261 uint64_t *deadline); 262 263extern void thread_call_func( 264 thread_call_func_t func, 265 thread_call_param_t param, 266 boolean_t unique_call); 267 268extern void thread_call_func_delayed( 269 thread_call_func_t func, 270 thread_call_param_t param, 271 uint64_t deadline); 272 273extern boolean_t thread_call_func_cancel( 274 thread_call_func_t func, 275 thread_call_param_t param, 276 boolean_t cancel_all); 277 278#else /* __LP64__ */ 279 280#ifdef XNU_KERNEL_PRIVATE 281 282extern void thread_call_func_delayed( 283 thread_call_func_t func, 284 thread_call_param_t param, 285 uint64_t deadline); 286 287extern boolean_t thread_call_func_cancel( 288 thread_call_func_t func, 289 thread_call_param_t param, 290 boolean_t cancel_all); 291 292#endif /* XNU_KERNEL_PRIVATE */ 293 294#endif /* __LP64__ */ 295 296#ifndef MACH_KERNEL_PRIVATE 297 298#ifndef __LP64__ 299 300#ifndef ABSOLUTETIME_SCALAR_TYPE 301 302#define thread_call_enter_delayed(a, b) \ 303 thread_call_enter_delayed((a), __OSAbsoluteTime(b)) 304 305#define thread_call_enter1_delayed(a, b, c) \ 306 thread_call_enter1_delayed((a), (b), __OSAbsoluteTime(c)) 307 308#define thread_call_is_delayed(a, b) \ 309 thread_call_is_delayed((a), __OSAbsoluteTimePtr(b)) 310 311#define thread_call_func_delayed(a, b, c) \ 312 thread_call_func_delayed((a), (b), __OSAbsoluteTime(c)) 313 314#endif /* ABSOLUTETIME_SCALAR_TYPE */ 315 316#endif /* __LP64__ */ 317 318#endif /* MACH_KERNEL_PRIVATE */ 319 320__END_DECLS 321 322#endif /* KERNEL_PRIVATE */ 323 324#endif /* _KERN_THREAD_CALL_H_ */ 325