xref: /xnu-10063.121.3/osfmk/arm/preemption_disable_internal.h (revision 2c2f96dc2b9a4408a43d3150ae9c105355ca3daa)
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28 
29 #include <kern/percpu.h>
30 #include <stdatomic.h>
31 #include <stdbool.h>
32 #include <stdint.h>
33 
34 #pragma once
35 
36 #if CONFIG_SPTM
37 /*
38  * This header is only meant for the PPL and SPTM to access the preemption disable data structure directly.
39  */
40 #endif /* CONFIG_SPTM */
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 	/**
48 	 * A snapshot of times and counters relevant to preemption disable measurement.
49 	 */
50 	struct _preemption_disable_snap {
51 		/* The time when preemption was disabled, in Mach time units. */
52 		uint64_t pds_mach_time;
53 		/* The amount of time spent in interrupts by the current CPU, in Mach time units. */
54 		uint64_t pds_int_mach_time;
55 #if CONFIG_CPU_COUNTERS
56 		/* The number of cycles elapsed on this CPU. */
57 		uint64_t pds_cycles;
58 		/* The number of instructions seen by this CPU. */
59 		uint64_t pds_instrs;
60 #endif /* CONFIG_CPU_COUNTERS */
61 	}
62 	/* At the start of the preemption disabled window. */
63 	pdp_start;
64 
65 	/* The maximum duration seen by this CPU, in Mach time units. */
66 	_Atomic uint64_t pdp_max_mach_duration;
67 	/*
68 	 * Whether to abandon the measurement on this CPU,
69 	 * due to a call to abandon_preemption_disable_measurement().
70 	 */
71 	bool pdp_abandon;
72 };
73 
74 PERCPU_DECL(struct _preemption_disable_pcpu, _preemption_disable_pcpu_data);
75