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#ifndef _KERN_SCHED_RT_H_
#define _KERN_SCHED_RT_H_
#include <kern/kern_types.h>
#include <kern/sched_common.h>
#include <kern/processor.h>
#include <kern/sched_prim.h>
__BEGIN_DECLS
#pragma mark - Constants and Tunables
#if (DEVELOPMENT || DEBUG || SCHED_TEST_HARNESS)
extern unsigned sched_rt_spill_policy;
extern unsigned sched_rt_steal_policy;
#endif /* (DEVELOPMENT || DEBUG || SCHED_TEST_HARNESS) */
extern uint32_t rt_deadline_epsilon;
extern uint32_t rt_constraint_threshold;
extern int sched_rt_runq_strict_priority;
extern int sched_allow_rt_smt;
#pragma mark - Initialization
void sched_realtime_timebase_init(void);
/* Initialize realtime runqueues for the given pset. */
void sched_rt_init_pset(processor_set_t pset);
/* Called once all psets are initialized. */
void sched_rt_init_completed(void);
#if CONFIG_SCHED_EDGE
#pragma mark - Realtime Scheduler-CLPC Interface
/*
* The realtime scheduler uses edges between psets to define policies
* regarding migration and steal operations, similar to the edge scheduler.
* The weights define an explicit search order for the scheduler to identify
* alternative psets when a realtime thread's preferred pset is overloaded.
*
* The matrix can be directly manipulated with
* sched_rt_config_set()/sched_rt_config_get(), but the preferred interface for
* updates is to call sched_rt_matrix_set(), which will update cached values
* computed from the matrix.
*/
void sched_rt_config_set(pset_id_t src_pset, pset_id_t dst_pset, sched_clutch_edge edge_config);
sched_clutch_edge sched_rt_config_get(pset_id_t src_pset, pset_id_t dst_pset);
/*
* sched_rt_matrix_get()/sched_rt_matrix_set()
*
* Selectively retrieve (or update, respectively) multiple edges in the realtime
* matrix. The realtime spill order is recomputed for every pset with a changed
* outgoing edge.
*
* The matrix provided should be `num_psets * num_psets`, where `num_psets`
* is equal to `sched_edge_max_clusters`. Like the Edge matrix, it is indexed
* first by source pset (major), then by destination pset (minor).
*/
void sched_rt_matrix_get(sched_clutch_edge *rt_matrix, bool *edge_requests, uint64_t num_psets);
void sched_rt_matrix_set(sched_clutch_edge *rt_matrix, bool *edge_changes, uint64_t num_psets);
#endif /* CONFIG_SCHED_EDGE */
#pragma mark - Scheduler Callouts
#if CONFIG_SCHED_SMT
/* SMT-aware callout for rt_choose_processor. */
processor_t sched_rtlocal_choose_processor_smt(processor_set_t starting_pset, processor_t processor, thread_t thread);
#else /* !CONFIG_SCHED_SMT */
processor_t sched_rt_choose_processor(processor_set_t starting_pset, processor_t processor, thread_t thread);
#endif /* !CONFIG_SCHED_SMT */
#if CONFIG_SCHED_EDGE
thread_t sched_rt_steal_thread(processor_set_t stealing_pset);
#endif /* CONFIG_SCHED_EDGE */
thread_t sched_rt_choose_thread(processor_t processor);
void sched_rt_queue_shutdown(processor_t processor);
void sched_rt_runq_scan(sched_update_scan_context_t scan_context);
int64_t sched_rt_runq_count_sum(void);
#pragma mark - Utilities
/*
* We are in the process of migrating realtime scheduler code into sched_rt.c
* to make it unit-testable in isolation.
*
* For the time being, these methods are made accessible to code that include
* sched_rt.h. They will be made static members of sched_rt.c as soon as
* practicable.
*/
uint64_t rt_deadline_add(uint64_t d, uint64_t e);
cpumap_t pset_available_but_not_running_rt_threads_cpumap(processor_set_t pset);
processor_t
pset_choose_furthest_deadline_processor_for_realtime_thread(
processor_set_t pset,
int max_pri,
uint64_t minimum_deadline,
processor_t skip_processor,
bool skip_spills,
bool include_ast_urgent_pending_cpus);
#if CONFIG_SCHED_SMT
processor_t pset_choose_processor_for_realtime_thread_smt(
processor_set_t pset,
processor_t skip_processor,
bool consider_secondaries,
bool skip_spills);
#else /* !CONFIG_SCHED_SMT */
processor_t
pset_choose_processor_for_realtime_thread(
processor_set_t pset,
processor_t skip_processor,
bool skip_spills);
#endif /* !CONFIG_SCHED_SMT */
#if CONFIG_SCHED_EDGE
bool rt_pset_has_stealable_threads(processor_set_t pset);
void pset_update_rt_stealable_state(processor_set_t pset);
/* Realtime spill is only supported on platforms with the edge scheduler. */
bool rt_choose_next_processor_for_spill_IPI(processor_set_t starting_pset, processor_t chosen_processor, processor_t *result_processor, sched_ipi_type_t *result_ipi_type);
#else /* !CONFIG_SCHED_EDGE */
#define pset_update_rt_stealable_state(x) do {(void) x;} while (0)
#endif /* !CONFIG_SCHED_EDGE */
bool rt_pset_needs_a_followup_IPI(processor_set_t pset);
void rt_choose_next_processor_for_followup_IPI(processor_set_t pset, processor_t chosen_processor, processor_t *result_processor, sched_ipi_type_t *result_ipi_type);
bool rt_clear_pending_spill(processor_t processor, int reason);
#pragma mark - Realtime Runqueues
#if DEBUG || SCHED_TEST_HARNESS
void check_rt_runq_consistency(rt_queue_t rt_run_queue, thread_t thread);
#define CHECK_RT_RUNQ_CONSISTENCY(q, th) check_rt_runq_consistency(q, th)
#else /* !(DEBUG || SCHED_TEST_HARNESS) */
#define CHECK_RT_RUNQ_CONSISTENCY(q, th) do {} while (0)
#endif /* !(DEBUG || SCHED_TEST_HARNESS) */
int rt_runq_count(processor_set_t);
thread_t rt_runq_dequeue(rt_queue_t rt_run_queue);
uint64_t rt_runq_earliest_deadline(processor_set_t);
thread_t rt_runq_first(rt_queue_t rt_run_queue);
bool rt_runq_insert(processor_t processor, processor_set_t pset, thread_t thread);
bool rt_runq_is_low_latency(processor_set_t pset);
int rt_runq_priority(processor_set_t pset);
void rt_runq_remove(rt_queue_t rt_run_queue, thread_t thread);
__END_DECLS
#endif /* _KERN_SCHED_RT_H_ */