private/qos_private.h

   1 /*
   2  * Copyright (c) 2013-2014 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #ifndef _QOS_PRIVATE_H
  25 #define _QOS_PRIVATE_H
  26
  27 #include <pthread/qos.h>
  28 #include <sys/qos_private.h>
  29
  30 #if __DARWIN_C_LEVEL >= __DARWIN_C_FULL
  31 // allow __DARWIN_C_LEVEL to turn off the use of mach_port_t
  32 #include <mach/port.h>
  33 #endif
  34
  35 // pthread_priority_t is an on opaque integer that is guaranteed to be ordered such that
  36 // combations of QoS classes and relative priorities are ordered numerically, according to
  37 // their combined priority.
  38 typedef unsigned long pthread_priority_t;
  39
  40 // masks for splitting the handling the contents of a pthread_priority_t, the mapping from
  41 // qos_class_t to the class bits, however, is intentionally not exposed.
  42 #define _PTHREAD_PRIORITY_FLAGS_MASK            (~0xffffff)
  43 #define _PTHREAD_PRIORITY_QOS_CLASS_MASK        0x00ffff00
  44 #define _PTHREAD_PRIORITY_QOS_CLASS_SHIFT       (8ull)
  45 #define _PTHREAD_PRIORITY_PRIORITY_MASK         0x000000ff
  46 #define _PTHREAD_PRIORITY_PRIORITY_SHIFT        (0)
  47
  48 #define _PTHREAD_PRIORITY_OVERCOMMIT_FLAG       0x80000000
  49 #define _PTHREAD_PRIORITY_INHERIT_FLAG          0x40000000
  50 #define _PTHREAD_PRIORITY_ROOTQUEUE_FLAG        0x20000000
  51 #define _PTHREAD_PRIORITY_ENFORCE_FLAG          0x10000000
  52 #define _PTHREAD_PRIORITY_OVERRIDE_FLAG         0x08000000
  53
  54 // redeffed here to avoid leaving __QOS_ENUM defined in the public header
  55 #define __QOS_ENUM(name, type, ...) enum { __VA_ARGS__ }; typedef type name##_t
  56 #define __QOS_AVAILABLE_STARTING(x, y)
  57
  58 #if defined(__has_feature) && defined(__has_extension)
  59 #if __has_feature(objc_fixed_enum) || __has_extension(cxx_strong_enums)
  60 #undef __QOS_ENUM
  61 #define __QOS_ENUM(name, type, ...) typedef enum : type { __VA_ARGS__ } name##_t
  62 #endif
  63 #if __has_feature(enumerator_attributes)
  64 #undef __QOS_AVAILABLE_STARTING
  65 #define __QOS_AVAILABLE_STARTING __OSX_AVAILABLE_STARTING
  66 #endif
  67 #endif
  68
  69 __QOS_ENUM(_pthread_set_flags, unsigned int,
  70    _PTHREAD_SET_SELF_QOS_FLAG
  71                    __QOS_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0) = 0x1,
  72    _PTHREAD_SET_SELF_VOUCHER_FLAG
  73                    __QOS_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0) = 0x2,
  74    _PTHREAD_SET_SELF_FIXEDPRIORITY_FLAG
  75                    __QOS_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0) = 0x4,
  76 );
  77
  78 #undef __QOS_ENUM
  79 #undef __QOS_AVAILABLE_STARTING
  80
  81 #ifndef KERNEL
  82
  83 __BEGIN_DECLS
  84
  85 /*!
  86  * @function pthread_set_qos_class_np
  87  *
  88  * @abstract
  89  * Sets the requested QOS class and relative priority of the current thread.
  90  *
  91  * @discussion
  92  * The QOS class and relative priority represent an overall combination of
  93  * system quality of service attributes on a thread.
  94  *
  95  * Subsequent calls to interfaces such as pthread_setschedparam() that are
  96  * incompatible or in conflict with the QOS class system will unset the QOS
  97  * class requested with this interface and pthread_get_qos_class_np() will
  98  * return QOS_CLASS_UNSPECIFIED thereafter. A thread so modified is permanently
  99  * opted-out of the QOS class system and calls to this function to request a QOS
 100  * class for such a thread will fail and return EPERM.
 101  *
 102  * @param __pthread
 103  * The current thread as returned by pthread_self().
 104  * EINVAL will be returned if any other thread is provided.
 105  *
 106  * @param __qos_class
 107  * A QOS class value:
 108  *      - QOS_CLASS_USER_INTERACTIVE
 109  *      - QOS_CLASS_USER_INITIATED
 110  *      - QOS_CLASS_DEFAULT
 111  *      - QOS_CLASS_UTILITY
 112  *      - QOS_CLASS_BACKGROUND
 113  *      - QOS_CLASS_MAINTENANCE
 114  * EINVAL will be returned if any other value is provided.
 115  *
 116  * @param __relative_priority
 117  * A relative priority within the QOS class. This value is a negative offset
 118  * from the maximum supported scheduler priority for the given class.
 119  * EINVAL will be returned if the value is greater than zero or less than
 120  * QOS_MIN_RELATIVE_PRIORITY.
 121  *
 122  * @return
 123  * Zero if successful, othwerise an errno value.
 124  */
 125 __OSX_AVAILABLE_BUT_DEPRECATED_MSG(__MAC_10_10, __MAC_10_10, __IPHONE_8_0, __IPHONE_8_0, \
 126                 "Use pthread_set_qos_class_self_np() instead")
 127 int
 128 pthread_set_qos_class_np(pthread_t __pthread,
 129                                                  qos_class_t __qos_class,
 130                                                  int __relative_priority);
 131
 132 /* Private interfaces for libdispatch to encode/decode specific values of pthread_priority_t. */
 133
 134 // Encode a class+priority pair into a pthread_priority_t,
 135 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 136 pthread_priority_t
 137 _pthread_qos_class_encode(qos_class_t qos_class, int relative_priority, unsigned long flags);
 138
 139 // Decode a pthread_priority_t into a class+priority pair.
 140 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 141 qos_class_t
 142 _pthread_qos_class_decode(pthread_priority_t priority, int *relative_priority, unsigned long *flags);
 143
 144 // Encode a legacy workqueue API priority into a pthread_priority_t
 145 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 146 pthread_priority_t
 147 _pthread_qos_class_encode_workqueue(int queue_priority, unsigned long flags);
 148
 149 #if __DARWIN_C_LEVEL >= __DARWIN_C_FULL
 150 // Set QoS or voucher, or both, on pthread_self()
 151 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 152 int
 153 _pthread_set_properties_self(_pthread_set_flags_t flags, pthread_priority_t priority, mach_port_t voucher);
 154
 155 // Set self to fixed priority without disturbing QoS or priority
 156 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 157 int
 158 pthread_set_fixedpriority_self(void);
 159
 160 #endif
 161
 162 __END_DECLS
 163
 164 #endif // KERNEL
 165
 166 #endif //_QOS_PRIVATE_H