Dear Ketan...
> I am extremely sorry. Ofcourse the VMA is shared while cloning the
> process, what I meant was the mm_struct which is inside the
> task_struct. The mm_struct is the one which contains the list of
> VMA's the process can access. And thats what I meant by "copying of
> VMA values"... yeah the wording of my mail was confusing...I agree
Well, actually, you are almost there :) If you read kernel/fork.c on
copy_mm():
struct mm_struct * mm, *oldmm;
<snip>
oldmm = current->mm;
<snip>
if (clone_flags & CLONE_VM) {
atomic_inc(&oldmm->mm_users);
mm = oldmm;
<snip>
spin_unlock_wait(&oldmm->page_table_lock);
goto good_mm;
<snip>
good_mm:
tsk->mm = mm;
tsk->active_mm = mm;
return 0;
You can conclude that both mm_struct are actually pointing into single
structure in memory. How do we know that it is shared? by looking at
mm_users...:)
regards
Mulyadi
--
Kernelnewbies: Help each other learn about the Linux kernel.
Archive: http://mail.nl.linux.org/kernelnewbies/
FAQ: http://kernelnewbies.org/faq/
