Узнать, находится ли в кеше процессора переменная?

A *a = new A(); // выделили память
a->foo();; //page fault

#include <stdio.h>
#include <unistd.h>
 
#include <sys/sdt.h>
#include <sys/types.h>
#include <sys/syscall.h>
 
struct A
{
    void foo()
    {   
        a = 42; 
    }   
 
    int a;
};
 
int main()
{
    pid_t x = syscall(__NR_gettid);
 
    DTRACE_PROBE1(pf_test, thread_id, (int)x);
    DTRACE_PROBE(pf_test, begin);
    A *a = new A;
    a->foo();
    DTRACE_PROBE(pf_test, end);
    printf("a: %p\n", a); 
    return 0;
}
 
thread id 25394
fault address: 0x601008, symbol: 0x601008, access: w, type: minor, delay: 4
 
a: 0x601010

#! /usr/bin/env stap
 
global fentry_time, fexit_time, faddress, fsymbol, faccess, ftype
global thread_id, dump, fdumped
 
probe process("pf_test").mark("thread_id")
{
    thread_id = $arg1
    printf("thread id %d\n", thread_id)
}
 
probe process("pf_test").mark("begin")
{
    dump = 1 
    fdumped = 1 
}
 
probe process("pf_test").mark("end")
{
    dump = 0 
 
    if (!fdumped)
    {   
        e = fexit_time - fentry_time
        printf("fault address: %p, symbol: %s, access: %s, type: %s, delay: %d\n",
            faddress, fsymbol, faccess, ftype, e)
        fdumped = 1 
    }   
}
 
probe vm.pagefault
{
    if (!(dump && tid() == thread_id)) next
 
    fentry_time = gettimeofday_us()
    faddress = address
    fsymbol = usymdata(address)
    faccess = write_access ? "w" : "r" 
}
 
probe vm.pagefault.return
{
    if (!(dump && tid() == thread_id)) next
    fexit_time = gettimeofday_us()
 
    if (vm_fault_contains(fault_type, VM_FAULT_MINOR))
    {   
        ftype = "minor"
    }   
    else if (vm_fault_contains(fault_type, VM_FAULT_MAJOR))
    {   
        ftype = "major"
    }   
    else
    {   
        next #only want to deal with minor and major page faults
    }   
 
    fdumped = 0 
}