xref: /xnu-11417.121.6/osfmk/kern/sched_amp_common.h (revision a1e26a70f38d1d7daa7b49b258e2f8538ad81650)
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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 bool 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 uint32_t sched_amp_qos_max_parallelism(int qos, uint64_t options);
70 void sched_amp_bounce_thread_group_from_ecores(processor_set_t pset, struct thread_group *tg);
71 
72 pset_node_t sched_amp_choose_node(thread_t thread);
73 
74 #endif /* __AMP__ */
75 
76 #endif /* _KERN_SCHED_AMP_COMMON_H_ */
77