NtCreateIRTimer - NtDoc

#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_WIN8)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtCreateIRTimer(
    _Out_ PHANDLE TimerHandle,
    _In_ PVOID Reserved,
    _In_ ACCESS_MASK DesiredAccess
    );

#endif
#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCreateIRTimer(
    _Out_ PHANDLE TimerHandle,
    _In_ PVOID Reserved,
    _In_ ACCESS_MASK DesiredAccess
    );

#endif
View code on GitHub