osfmk/kern/sched_amp_common.h

   1 /*
   2  * Copyright (c) 2019 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 #ifndef _KERN_SCHED_AMP_COMMON_H_
  30 #define _KERN_SCHED_AMP_COMMON_H_
  31
  32 #if __AMP__
  33
  34 /* Routine to initialize processor sets on AMP platforms */
  35 void sched_amp_init(void);
  36
  37 /*
  38  * The AMP scheduler uses spill/steal/rebalance logic to make sure the most appropriate threads
  39  * are scheduled on the P/E clusters. Here are the definitions of those terms:
  40  *
  41  * - Spill:     Spill threads from an overcommited P-cluster onto the E-cluster. This is needed to make sure
  42  *              that high priority P-recommended threads experience low scheduling latency in the presence of
  43  *              lots of P-recommended threads.
  44  *
  45  * - Steal:     From an E-core, steal a thread from the P-cluster to provide low scheduling latency for
  46  *              P-recommended threads.
  47  *
  48  * - Rebalance: Once a P-core goes idle, check if the E-cores are running any P-recommended threads and
  49  *              bring it back to run on its recommended cluster type.
  50  */
  51
  52 /* Spill logic */
  53 int sched_amp_spill_threshold(processor_set_t pset);
  54 void pset_signal_spill(processor_set_t pset, int spilled_thread_priority);
  55 bool pset_should_accept_spilled_thread(processor_set_t pset, int spilled_thread_priority);
  56 bool should_spill_to_ecores(processor_set_t nset, thread_t thread);
  57 void sched_amp_check_spill(processor_set_t pset, thread_t thread);
  58
  59 /* Steal logic */
  60 int sched_amp_steal_threshold(processor_set_t pset, bool spill_pending);
  61 bool sched_amp_steal_thread_enabled(processor_set_t pset);
  62
  63 /* Rebalance logic */
  64 void sched_amp_balance(processor_t cprocessor, processor_set_t cpset);
  65
  66 /* IPI policy */
  67 sched_ipi_type_t sched_amp_ipi_policy(processor_t dst, thread_t thread, boolean_t dst_idle, sched_ipi_event_t event);
  68
  69 /* AMP realtime runq management */
  70 rt_queue_t sched_amp_rt_runq(processor_set_t pset);
  71 void sched_amp_rt_init(processor_set_t pset);
  72 void sched_amp_rt_queue_shutdown(processor_t processor);
  73 void sched_amp_rt_runq_scan(sched_update_scan_context_t scan_context);
  74 int64_t sched_amp_rt_runq_count_sum(void);
  75
  76 uint32_t sched_amp_qos_max_parallelism(int qos, uint64_t options);
  77 void sched_amp_bounce_thread_group_from_ecores(processor_set_t pset, struct thread_group *tg);
  78
  79 pset_node_t sched_amp_choose_node(thread_t thread);
  80
  81 #endif /* __AMP__ */
  82
  83 #endif /* _KERN_SCHED_AMP_COMMON_H_ */