xref: /xnu-12377.41.6/osfmk/arm/preemption_disable_internal.h (revision bbb1b6f9e71b8cdde6e5cd6f4841f207dee3d828)
1 /*
2  * Copyright (c) 2020-2023 Apple Inc. All rights reserved.
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28 
29 #include <kern/percpu.h>
30 #include <kern/timeout.h>
31 #include <stdatomic.h>
32 #include <stdbool.h>
33 #include <stdint.h>
34 
35 #pragma once
36 
37 /*
38  * This header is only meant for the PPL and SPTM pmap to access the preemption disable data
39  * structure directly for the purposes of managing timeouts.
40  */
41 
42 /**
43  * Track time and other counters during a preemption disabled window,
44  * when `SCHED_HYGIENE` is configured.
45  */
46 struct _preemption_disable_pcpu {
47 	/* Timeout structure to track this preemption disable. */
48 	kern_timeout_t pdp_timeout;
49 
50 	/* The maximum duration seen by this CPU, in Mach time units. */
51 	_Atomic uint64_t pdp_max_mach_duration;
52 };
53 
54 PERCPU_DECL(struct _preemption_disable_pcpu, _preemption_disable_pcpu_data);
55