src/shims/priority.h

   1 /*
   2  * Copyright (c) 2008-2016 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_APACHE_LICENSE_HEADER_START@
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  *
  18  * @APPLE_APACHE_LICENSE_HEADER_END@
  19  */
  20
  21 /*
  22  * IMPORTANT: This header file describes INTERNAL interfaces to libdispatch
  23  * which are subject to change in future releases of Mac OS X. Any applications
  24  * relying on these interfaces WILL break.
  25  */
  26
  27 #ifndef __DISPATCH_SHIMS_PRIORITY__
  28 #define __DISPATCH_SHIMS_PRIORITY__
  29
  30 #if HAVE_PTHREAD_QOS_H && __has_include(<pthread/qos_private.h>)
  31 #include <pthread/qos.h>
  32 #include <pthread/qos_private.h>
  33 #ifndef _PTHREAD_PRIORITY_OVERCOMMIT_FLAG
  34 #define _PTHREAD_PRIORITY_OVERCOMMIT_FLAG 0x80000000
  35 #endif
  36 #ifndef _PTHREAD_PRIORITY_SCHED_PRI_FLAG
  37 #define _PTHREAD_PRIORITY_SCHED_PRI_FLAG 0x20000000
  38 #endif
  39 #ifndef _PTHREAD_PRIORITY_DEFAULTQUEUE_FLAG
  40 #define _PTHREAD_PRIORITY_DEFAULTQUEUE_FLAG 0x04000000
  41 #endif
  42 #ifndef _PTHREAD_PRIORITY_EVENT_MANAGER_FLAG
  43 #define _PTHREAD_PRIORITY_EVENT_MANAGER_FLAG 0x02000000
  44 #endif
  45 #ifndef _PTHREAD_PRIORITY_NEEDS_UNBIND_FLAG
  46 #define _PTHREAD_PRIORITY_NEEDS_UNBIND_FLAG 0x01000000
  47 #endif
  48 #else // HAVE_PTHREAD_QOS_H
  49 OS_ENUM(qos_class, unsigned int,
  50         QOS_CLASS_USER_INTERACTIVE = 0x21,
  51         QOS_CLASS_USER_INITIATED = 0x19,
  52         QOS_CLASS_DEFAULT = 0x15,
  53         QOS_CLASS_UTILITY = 0x11,
  54         QOS_CLASS_BACKGROUND = 0x09,
  55         QOS_CLASS_MAINTENANCE = 0x05,
  56         QOS_CLASS_UNSPECIFIED = 0x00,
  57 );
  58 typedef unsigned long pthread_priority_t;
  59 #define QOS_MIN_RELATIVE_PRIORITY (-15)
  60 #define _PTHREAD_PRIORITY_FLAGS_MASK (~0xffffff)
  61 #define _PTHREAD_PRIORITY_QOS_CLASS_MASK 0x00ffff00
  62 #define _PTHREAD_PRIORITY_QOS_CLASS_SHIFT (8ull)
  63 #define _PTHREAD_PRIORITY_PRIORITY_MASK 0x000000ff
  64 #define _PTHREAD_PRIORITY_OVERCOMMIT_FLAG 0x80000000
  65 #define _PTHREAD_PRIORITY_SCHED_PRI_FLAG 0x20000000
  66 #define _PTHREAD_PRIORITY_DEFAULTQUEUE_FLAG 0x04000000
  67 #define _PTHREAD_PRIORITY_EVENT_MANAGER_FLAG 0x02000000
  68 #define _PTHREAD_PRIORITY_NEEDS_UNBIND_FLAG 0x01000000
  69 #define _PTHREAD_PRIORITY_ENFORCE_FLAG  0x10000000
  70
  71 #endif // HAVE_PTHREAD_QOS_H
  72
  73 typedef uint32_t dispatch_qos_t;
  74 typedef uint32_t dispatch_priority_t;
  75 typedef uint32_t dispatch_priority_t;
  76 typedef uint16_t dispatch_priority_requested_t;
  77
  78 #define DISPATCH_QOS_UNSPECIFIED            ((dispatch_qos_t)0)
  79 #define DISPATCH_QOS_MAINTENANCE            ((dispatch_qos_t)1)
  80 #define DISPATCH_QOS_BACKGROUND             ((dispatch_qos_t)2)
  81 #define DISPATCH_QOS_UTILITY                ((dispatch_qos_t)3)
  82 #define DISPATCH_QOS_DEFAULT                ((dispatch_qos_t)4)
  83 #define DISPATCH_QOS_USER_INITIATED         ((dispatch_qos_t)5)
  84 #define DISPATCH_QOS_USER_INTERACTIVE       ((dispatch_qos_t)6)
  85 #define DISPATCH_QOS_MAX                    DISPATCH_QOS_USER_INTERACTIVE
  86 #define DISPATCH_QOS_SATURATED              ((dispatch_qos_t)15)
  87
  88 #define DISPATCH_PRIORITY_RELPRI_MASK        ((dispatch_priority_t)0x000000ff)
  89 #define DISPATCH_PRIORITY_RELPRI_SHIFT       0
  90 #define DISPATCH_PRIORITY_QOS_MASK           ((dispatch_priority_t)0x0000ff00)
  91 #define DISPATCH_PRIORITY_QOS_SHIFT          8
  92 #define DISPATCH_PRIORITY_REQUESTED_MASK     ((dispatch_priority_t)0x0000ffff)
  93 #define DISPATCH_PRIORITY_OVERRIDE_MASK      ((dispatch_priority_t)0x00ff0000)
  94 #define DISPATCH_PRIORITY_OVERRIDE_SHIFT     16
  95 #define DISPATCH_PRIORITY_FLAGS_MASK         ((dispatch_priority_t)0xff000000)
  96
  97 #define DISPATCH_PRIORITY_SATURATED_OVERRIDE ((dispatch_priority_t)0x000f0000)
  98
  99 #define DISPATCH_PRIORITY_FLAG_OVERCOMMIT    ((dispatch_priority_t)0x80000000) // _PTHREAD_PRIORITY_OVERCOMMIT_FLAG
 100 #define DISPATCH_PRIORITY_FLAG_DEFAULTQUEUE  ((dispatch_priority_t)0x04000000) // _PTHREAD_PRIORITY_DEFAULTQUEUE_FLAG
 101 #define DISPATCH_PRIORITY_FLAG_MANAGER       ((dispatch_priority_t)0x02000000) // _PTHREAD_PRIORITY_EVENT_MANAGER_FLAG
 102 #define DISPATCH_PRIORITY_PTHREAD_PRIORITY_FLAGS_MASK \
 103                 (DISPATCH_PRIORITY_FLAG_OVERCOMMIT | DISPATCH_PRIORITY_FLAG_DEFAULTQUEUE | \
 104                 DISPATCH_PRIORITY_FLAG_MANAGER)
 105
 106 // not passed to pthread
 107 #define DISPATCH_PRIORITY_FLAG_INHERIT       ((dispatch_priority_t)0x40000000) // _PTHREAD_PRIORITY_INHERIT_FLAG
 108 #define DISPATCH_PRIORITY_FLAG_ENFORCE       ((dispatch_priority_t)0x10000000) // _PTHREAD_PRIORITY_ENFORCE_FLAG
 109 #define DISPATCH_PRIORITY_FLAG_ROOTQUEUE     ((dispatch_priority_t)0x20000000) // _PTHREAD_PRIORITY_ROOTQUEUE_FLAG
 110
 111 #pragma mark dispatch_qos
 112
 113 DISPATCH_ALWAYS_INLINE
 114 static inline dispatch_qos_t
 115 _dispatch_qos_from_qos_class(qos_class_t cls)
 116 {
 117         switch ((unsigned int)cls) {
 118         case QOS_CLASS_USER_INTERACTIVE: return DISPATCH_QOS_USER_INTERACTIVE;
 119         case QOS_CLASS_USER_INITIATED:   return DISPATCH_QOS_USER_INITIATED;
 120         case QOS_CLASS_DEFAULT:          return DISPATCH_QOS_DEFAULT;
 121         case QOS_CLASS_UTILITY:          return DISPATCH_QOS_UTILITY;
 122         case QOS_CLASS_BACKGROUND:       return DISPATCH_QOS_BACKGROUND;
 123         case QOS_CLASS_MAINTENANCE:      return DISPATCH_QOS_MAINTENANCE;
 124         default: return DISPATCH_QOS_UNSPECIFIED;
 125         }
 126 }
 127
 128 DISPATCH_ALWAYS_INLINE
 129 static inline qos_class_t
 130 _dispatch_qos_to_qos_class(dispatch_qos_t qos)
 131 {
 132         switch (qos) {
 133         case DISPATCH_QOS_USER_INTERACTIVE: return QOS_CLASS_USER_INTERACTIVE;
 134         case DISPATCH_QOS_USER_INITIATED:   return QOS_CLASS_USER_INITIATED;
 135         case DISPATCH_QOS_DEFAULT:          return QOS_CLASS_DEFAULT;
 136         case DISPATCH_QOS_UTILITY:          return QOS_CLASS_UTILITY;
 137         case DISPATCH_QOS_BACKGROUND:       return QOS_CLASS_BACKGROUND;
 138         case DISPATCH_QOS_MAINTENANCE:      return (qos_class_t)QOS_CLASS_MAINTENANCE;
 139         default: return QOS_CLASS_UNSPECIFIED;
 140         }
 141 }
 142
 143 DISPATCH_ALWAYS_INLINE
 144 static inline dispatch_qos_t
 145 _dispatch_qos_from_queue_priority(long priority)
 146 {
 147         switch (priority) {
 148         case DISPATCH_QUEUE_PRIORITY_BACKGROUND:      return DISPATCH_QOS_BACKGROUND;
 149         case DISPATCH_QUEUE_PRIORITY_NON_INTERACTIVE: return DISPATCH_QOS_UTILITY;
 150         case DISPATCH_QUEUE_PRIORITY_LOW:             return DISPATCH_QOS_UTILITY;
 151         case DISPATCH_QUEUE_PRIORITY_DEFAULT:         return DISPATCH_QOS_DEFAULT;
 152         case DISPATCH_QUEUE_PRIORITY_HIGH:            return DISPATCH_QOS_USER_INITIATED;
 153         default: return _dispatch_qos_from_qos_class((qos_class_t)priority);
 154         }
 155 }
 156
 157 DISPATCH_ALWAYS_INLINE
 158 static inline dispatch_qos_t
 159 _dispatch_qos_from_pp(pthread_priority_t pp)
 160 {
 161         pp &= _PTHREAD_PRIORITY_QOS_CLASS_MASK;
 162         pp >>= _PTHREAD_PRIORITY_QOS_CLASS_SHIFT;
 163         return (dispatch_qos_t)__builtin_ffs((int)pp);
 164 }
 165
 166 DISPATCH_ALWAYS_INLINE
 167 static inline pthread_priority_t
 168 _dispatch_qos_to_pp(dispatch_qos_t qos)
 169 {
 170         pthread_priority_t pp;
 171         pp = 1ul << ((qos - 1) + _PTHREAD_PRIORITY_QOS_CLASS_SHIFT);
 172         return pp | _PTHREAD_PRIORITY_PRIORITY_MASK;
 173 }
 174
 175 // including maintenance
 176 DISPATCH_ALWAYS_INLINE
 177 static inline bool
 178 _dispatch_qos_is_background(dispatch_qos_t qos)
 179 {
 180         return qos && qos <= DISPATCH_QOS_BACKGROUND;
 181 }
 182
 183 #pragma mark dispatch_priority
 184
 185 #define _dispatch_priority_make(qos, relpri) \
 186         (qos ? ((((qos) << DISPATCH_PRIORITY_QOS_SHIFT) & DISPATCH_PRIORITY_QOS_MASK) | \
 187          ((dispatch_priority_t)(relpri - 1) & DISPATCH_PRIORITY_RELPRI_MASK)) : 0)
 188
 189 DISPATCH_ALWAYS_INLINE
 190 static inline dispatch_priority_t
 191 _dispatch_priority_with_override_qos(dispatch_priority_t pri,
 192                 dispatch_qos_t oqos)
 193 {
 194         pri &= ~DISPATCH_PRIORITY_OVERRIDE_MASK;
 195         pri |= oqos << DISPATCH_PRIORITY_OVERRIDE_SHIFT;
 196         return pri;
 197 }
 198
 199 DISPATCH_ALWAYS_INLINE
 200 static inline int
 201 _dispatch_priority_relpri(dispatch_priority_t dbp)
 202 {
 203         if (dbp & DISPATCH_PRIORITY_QOS_MASK) {
 204                 return (int8_t)(dbp & DISPATCH_PRIORITY_RELPRI_MASK) + 1;
 205         }
 206         return 0;
 207 }
 208
 209 DISPATCH_ALWAYS_INLINE
 210 static inline dispatch_qos_t
 211 _dispatch_priority_qos(dispatch_priority_t dbp)
 212 {
 213         dbp &= DISPATCH_PRIORITY_QOS_MASK;
 214         return dbp >> DISPATCH_PRIORITY_QOS_SHIFT;
 215 }
 216
 217 DISPATCH_ALWAYS_INLINE
 218 static inline dispatch_qos_t
 219 _dispatch_priority_override_qos(dispatch_priority_t dbp)
 220 {
 221         dbp &= DISPATCH_PRIORITY_OVERRIDE_MASK;
 222         return dbp >> DISPATCH_PRIORITY_OVERRIDE_SHIFT;
 223 }
 224
 225 DISPATCH_ALWAYS_INLINE
 226 static inline dispatch_priority_t
 227 _dispatch_priority_from_pp_impl(pthread_priority_t pp, bool keep_flags)
 228 {
 229         dispatch_assert(!(pp & _PTHREAD_PRIORITY_SCHED_PRI_FLAG));
 230
 231         dispatch_priority_t dbp;
 232         if (keep_flags) {
 233                 dbp = pp & (DISPATCH_PRIORITY_PTHREAD_PRIORITY_FLAGS_MASK |
 234                                 DISPATCH_PRIORITY_RELPRI_MASK);
 235         } else {
 236                 dbp = pp & DISPATCH_PRIORITY_RELPRI_MASK;
 237         }
 238
 239         dbp |= _dispatch_qos_from_pp(pp) << DISPATCH_PRIORITY_QOS_SHIFT;
 240         return dbp;
 241 }
 242 #define _dispatch_priority_from_pp(pp) \
 243                 _dispatch_priority_from_pp_impl(pp, true)
 244 #define _dispatch_priority_from_pp_strip_flags(pp) \
 245                 _dispatch_priority_from_pp_impl(pp, false)
 246
 247 DISPATCH_ALWAYS_INLINE
 248 static inline pthread_priority_t
 249 _dispatch_priority_to_pp_impl(dispatch_priority_t dbp, bool keep_flags)
 250 {
 251         pthread_priority_t pp;
 252         if (keep_flags) {
 253                 pp = dbp & (DISPATCH_PRIORITY_PTHREAD_PRIORITY_FLAGS_MASK |
 254                                 DISPATCH_PRIORITY_RELPRI_MASK);
 255         } else {
 256                 pp = dbp & DISPATCH_PRIORITY_RELPRI_MASK;
 257         }
 258         dispatch_qos_t qos = _dispatch_priority_qos(dbp);
 259         if (qos) {
 260                 pp |= (1ul << ((qos - 1) + _PTHREAD_PRIORITY_QOS_CLASS_SHIFT));
 261         }
 262         return pp;
 263 }
 264 #define _dispatch_priority_to_pp(pp) \
 265                 _dispatch_priority_to_pp_impl(pp, true)
 266 #define _dispatch_priority_to_pp_strip_flags(pp) \
 267                 _dispatch_priority_to_pp_impl(pp, false)
 268
 269 #endif // __DISPATCH_SHIMS_PRIORITY__