xref: /xnu-10002.81.5/osfmk/arm/preemption_disable_internal.h (revision 5e3eaea39dcf651e66cb99ba7d70e32cc4a99587)
1 /*
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27  */
28 
29 #include <kern/percpu.h>
30 #include <stdatomic.h>
31 #include <stdbool.h>
32 #include <stdint.h>
33 
34 #pragma once
35 
36 
37 /**
38  * Track time and other counters during a preemption disabled window,
39  * when `SCHED_HYGIENE` is configured.
40  */
41 struct _preemption_disable_pcpu {
42 	/**
43 	 * A snapshot of times and counters relevant to preemption disable measurement.
44 	 */
45 	struct _preemption_disable_snap {
46 		/* The time when preemption was disabled, in Mach time units. */
47 		uint64_t pds_mach_time;
48 		/* The amount of time spent in interrupts by the current CPU, in Mach time units. */
49 		uint64_t pds_int_mach_time;
50 #if MONOTONIC
51 		/* The number of cycles elapsed on this CPU. */
52 		uint64_t pds_cycles;
53 		/* The number of instructions seen by this CPU. */
54 		uint64_t pds_instrs;
55 #endif /* MONOTONIC */
56 	}
57 	/* At the start of the preemption disabled window. */
58 	pdp_start;
59 
60 	/* The maximum duration seen by this CPU, in Mach time units. */
61 	_Atomic uint64_t pdp_max_mach_duration;
62 	/*
63 	 * Whether to abandon the measurement on this CPU,
64 	 * due to a call to abandon_preemption_disable_measurement().
65 	 */
66 	bool pdp_abandon;
67 };
68 
69 PERCPU_DECL(struct _preemption_disable_pcpu, _preemption_disable_pcpu_data);
70