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_FLAGS_SHIFT       (24ull)
  44 #define _PTHREAD_PRIORITY_QOS_CLASS_MASK        0x00ffff00
  45 #define _PTHREAD_PRIORITY_QOS_CLASS_SHIFT       (8ull)
  46 #define _PTHREAD_PRIORITY_PRIORITY_MASK         0x000000ff
  47 #define _PTHREAD_PRIORITY_PRIORITY_SHIFT        (0)
  48
  49 #define _PTHREAD_PRIORITY_OVERCOMMIT_FLAG       0x80000000
  50 #define _PTHREAD_PRIORITY_INHERIT_FLAG          0x40000000
  51 #define _PTHREAD_PRIORITY_ROOTQUEUE_FLAG        0x20000000
  52 #define _PTHREAD_PRIORITY_ENFORCE_FLAG          0x10000000
  53 #define _PTHREAD_PRIORITY_OVERRIDE_FLAG         0x08000000
  54
  55 // libdispatch defines the following, so it's not safe to use for anything we
  56 // expect to be passed in from userspace
  57 //#define _PTHREAD_PRIORITY_DEFAULTQUEUE_FLAG 0x04000000
  58
  59 // The event manager flag indicates that this thread/request is for a event
  60 // manager thread.  There can only ever be one event manager thread at a time and
  61 // it is brought up at the highest of all event manager priorities passed to the
  62 // kext.
  63 #define _PTHREAD_PRIORITY_EVENT_MANAGER_FLAG    0x02000000
  64
  65 // Used to indicate to the pthread kext that the provided event manager thread
  66 // priority is actually a scheduling priority not a QoS.  We can have ROOTQUEUE_FLAG
  67 // perform double duty because it's never provided to the kernel.
  68 #define _PTHREAD_PRIORITY_SCHED_PRI_FLAG        0x20000000
  69
  70 // redeffed here to avoid leaving __QOS_ENUM defined in the public header
  71 #define __QOS_ENUM(name, type, ...) enum { __VA_ARGS__ }; typedef type name##_t
  72 #define __QOS_AVAILABLE_STARTING(x, y)
  73
  74 #if defined(__has_feature) && defined(__has_extension)
  75 #if __has_feature(objc_fixed_enum) || __has_extension(cxx_strong_enums)
  76 #undef __QOS_ENUM
  77 #define __QOS_ENUM(name, type, ...) typedef enum : type { __VA_ARGS__ } name##_t
  78 #endif
  79 #if __has_feature(enumerator_attributes)
  80 #undef __QOS_AVAILABLE_STARTING
  81 #define __QOS_AVAILABLE_STARTING __OSX_AVAILABLE_STARTING
  82 #endif
  83 #endif
  84
  85 __QOS_ENUM(_pthread_set_flags, unsigned int,
  86    _PTHREAD_SET_SELF_QOS_FLAG
  87                    __QOS_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0) = 0x1,
  88    _PTHREAD_SET_SELF_VOUCHER_FLAG
  89                    __QOS_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0) = 0x2,
  90    _PTHREAD_SET_SELF_FIXEDPRIORITY_FLAG
  91                    __QOS_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0) = 0x4,
  92    _PTHREAD_SET_SELF_TIMESHARE_FLAG
  93                    __QOS_AVAILABLE_STARTING(__MAC_10_11, __IPHONE_9_0) = 0x8,
  94 );
  95
  96 #undef __QOS_ENUM
  97 #undef __QOS_AVAILABLE_STARTING
  98
  99 #ifndef KERNEL
 100
 101 __BEGIN_DECLS
 102
 103 /*!
 104  * @function pthread_set_qos_class_np
 105  *
 106  * @abstract
 107  * Sets the requested QOS class and relative priority of the current thread.
 108  *
 109  * @discussion
 110  * The QOS class and relative priority represent an overall combination of
 111  * system quality of service attributes on a thread.
 112  *
 113  * Subsequent calls to interfaces such as pthread_setschedparam() that are
 114  * incompatible or in conflict with the QOS class system will unset the QOS
 115  * class requested with this interface and pthread_get_qos_class_np() will
 116  * return QOS_CLASS_UNSPECIFIED thereafter. A thread so modified is permanently
 117  * opted-out of the QOS class system and calls to this function to request a QOS
 118  * class for such a thread will fail and return EPERM.
 119  *
 120  * @param __pthread
 121  * The current thread as returned by pthread_self().
 122  * EINVAL will be returned if any other thread is provided.
 123  *
 124  * @param __qos_class
 125  * A QOS class value:
 126  *      - QOS_CLASS_USER_INTERACTIVE
 127  *      - QOS_CLASS_USER_INITIATED
 128  *      - QOS_CLASS_DEFAULT
 129  *      - QOS_CLASS_UTILITY
 130  *      - QOS_CLASS_BACKGROUND
 131  *      - QOS_CLASS_MAINTENANCE
 132  * EINVAL will be returned if any other value is provided.
 133  *
 134  * @param __relative_priority
 135  * A relative priority within the QOS class. This value is a negative offset
 136  * from the maximum supported scheduler priority for the given class.
 137  * EINVAL will be returned if the value is greater than zero or less than
 138  * QOS_MIN_RELATIVE_PRIORITY.
 139  *
 140  * @return
 141  * Zero if successful, othwerise an errno value.
 142  */
 143 __OSX_AVAILABLE_BUT_DEPRECATED_MSG(__MAC_10_10, __MAC_10_10, __IPHONE_8_0, __IPHONE_8_0, \
 144                 "Use pthread_set_qos_class_self_np() instead")
 145 int
 146 pthread_set_qos_class_np(pthread_t __pthread,
 147                                                  qos_class_t __qos_class,
 148                                                  int __relative_priority);
 149
 150 /* Private interfaces for libdispatch to encode/decode specific values of pthread_priority_t. */
 151
 152 // Encode a class+priority pair into a pthread_priority_t,
 153 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 154 pthread_priority_t
 155 _pthread_qos_class_encode(qos_class_t qos_class, int relative_priority, unsigned long flags);
 156
 157 // Decode a pthread_priority_t into a class+priority pair.
 158 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 159 qos_class_t
 160 _pthread_qos_class_decode(pthread_priority_t priority, int *relative_priority, unsigned long *flags);
 161
 162 // Encode a legacy workqueue API priority into a pthread_priority_t
 163 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 164 pthread_priority_t
 165 _pthread_qos_class_encode_workqueue(int queue_priority, unsigned long flags);
 166
 167 #if __DARWIN_C_LEVEL >= __DARWIN_C_FULL
 168 // Set QoS or voucher, or both, on pthread_self()
 169 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 170 int
 171 _pthread_set_properties_self(_pthread_set_flags_t flags, pthread_priority_t priority, mach_port_t voucher);
 172
 173 // Set self to fixed priority without disturbing QoS or priority
 174 __OSX_AVAILABLE_STARTING(__MAC_10_10, __IPHONE_8_0)
 175 int
 176 pthread_set_fixedpriority_self(void);
 177
 178 // Inverse of pthread_set_fixedpriority_self()
 179 __OSX_AVAILABLE_STARTING(__MAC_10_11, __IPHONE_9_0)
 180 int
 181 pthread_set_timeshare_self(void);
 182
 183 #endif
 184
 185 __END_DECLS
 186
 187 #endif // KERNEL
 188
 189 #endif //_QOS_PRIVATE_H