PAGE_SHIFT in sys_mlockall

[Benoît Lefebvre <benoit.lefebvre.2@ulaval.ca>]

Hi,

Consider the following lines of code from mlock.c

asmlinkage long sys_mlockall(int flags)
{
        unsigned long lock_limit;
...

        lock_limit = current->rlim[RLIMIT_MEMLOCK].rlim_cur;
        lock_limit >>= PAGE_SHIFT;
...
        if (current->mm->total_vm > lock_limit)
                goto out;
...

My question is about "lock_limit >>= PAGE_SHIFT;". I dont understand why
this line is needed. Why we cannot just compare rlim_cur with
current->mm->total_vm?
Thanks


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