osfmk/kperf/pet.h

   1 /*
   2  * Copyright (c) 2011-2018 Apple Computer, 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 #include <kern/thread.h>
  30 #include <stdbool.h>
  31
  32 #define KPERF_PET_DEFAULT_IDLE_RATE 15
  33
  34 extern bool kppet_lightweight_active;
  35 extern _Atomic uint32_t kppet_gencount;
  36
  37 /*
  38  * If `actionid` is non-zero, set up PET to sample the action.  Otherwise,
  39  * disable PET.
  40  */
  41 void kppet_config(unsigned int actionid);
  42
  43 /*
  44  * Reset PET back to its default settings.
  45  */
  46 void kppet_reset(void);
  47
  48 /*
  49  * Notify PET that new threads are switching on-CPU.
  50  */
  51 void kppet_on_cpu(thread_t thread, thread_continue_t continuation,
  52     uintptr_t *starting_frame);
  53
  54 /*
  55  * Wake the PET thread from its timer handler.
  56  */
  57 void kppet_wake_thread(void);
  58
  59 /*
  60  * For configuring PET from the sysctl interface.
  61  */
  62 int kppet_get_idle_rate(void);
  63 int kppet_set_idle_rate(int new_idle_rate);
  64 int kppet_get_lightweight_pet(void);
  65 int kppet_set_lightweight_pet(int on);
  66
  67 /*
  68  * Update whether lightweight PET is active when turning sampling on and off.
  69  */
  70 void kppet_lightweight_active_update(void);