InterruptTimeAccounting.cc

/*
 * Copyright (c) 2026, Pedigree Developers
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted.
 */
 
#include "pedigree/kernel/process/DeferredTimeAccounting.h"
#include "pedigree/kernel/process/InterruptTimeAccounting.h"
#include "pedigree/kernel/process/Thread.h"
#include "pedigree/kernel/processor/Processor.h"
#include "pedigree/kernel/processor/ProcessorInformation.h"
 
InterruptTimeAccounting::InterruptTimeAccounting(bool fromUserspace)
    : m_pThread(Processor::information().getCurrentThread()), m_bFromUserspace(fromUserspace) {
  if (!m_pThread || !m_pThread->getParent()) {
    m_pThread = nullptr;
    return;
  }
 
  m_pThread->transitionTime(KernelTimeTransition::interrupted(m_bFromUserspace),
                            KernelTimeTransition::handler());
}
 
InterruptTimeAccounting::~InterruptTimeAccounting() {
  if (!m_pThread) {
    return;
  }
 
  // A userspace-origin interrupt still has an ordinary kernel return tail.
  // Its final architecture boundary owns the Kernel -> User transition so
  // callbacks and subsystem work are charged to the kernel.
  if (!m_bFromUserspace) {
    m_pThread->transitionTime(KernelTimeTransition::handler(),
                              KernelTimeTransition::resumed(false));
  }
}
 
void InterruptTimeAccounting::finishUserReturn(Thread* thread) {
  if (thread && thread->currentTimeAccountingMode() == CpuTimeMode::Kernel) {
    thread->transitionTimeAtInterruptReturn(CpuTimeMode::Kernel, CpuTimeMode::User);
  }
}