⚠️ VeridianOS Kernel Documentation - This is low-level kernel code. All functions are unsafe unless explicitly marked otherwise. no_std

Module deadline

veridian_kernel::sched

Module deadline 

Source
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Earliest Deadline First (EDF) Deadline Scheduler

Implements SCHED_DEADLINE scheduling policy alongside the existing CFS scheduler. Deadline tasks always preempt CFS tasks. Among deadline tasks, the one with the earliest absolute deadline is selected. Admission control ensures total CPU utilization does not exceed 100% (using fixed-point arithmetic scaled by 1000).

Key concepts:

  • Runtime: Maximum execution time per period (nanoseconds)
  • Deadline: Relative deadline from start of period (nanoseconds)
  • Period: Activation period (nanoseconds)
  • Admission control: Sum of (runtime/period) for all tasks must not exceed 1.0
  • Replenishment: Runtime is reset at period boundaries

Structs§

DeadlineEntity
A deadline scheduling entity describing a task’s timing parameters.
DeadlineScheduler
The Earliest Deadline First (EDF) deadline scheduler.
SchedAttr
Scheduling attributes for sched_setattr-style interface.

Constants§

SCHED_DEADLINE
SCHED_DEADLINE policy constant (Linux-compatible value)