Hi all,
I would like to know if there is a way to identify
struct page that is cow (copy-on-write).
The way I figured out to identify cow pages is when
copy-on-write happens. I mean I identify cow pages
inside the do_wp_page(), the function that handles
copy-on-write. I have checked do_no_page() as well.
I have included a field (is_cow) in the struct page to
identify cow page.
struct page {
...
atomic_t is_cow;
}
But I wonder if it is possible to identify cow pages
before copy-on-write happens. So identify cow pages in
advance before any process tries to write to a cow
page.
I have checked the do_fork(), copy_process() and
copy_mm() function to try to identify cow pages during
the process creation, but no success. In copy_mm(),
just the mm (of current process) is provided to the
child process, but there are no references to struct
pages related to mm and its VMAs.
So when a page struct is considered a cow in the
kernel and its count variable is updated? Certainly
the counter page (page->_count) is updated when a page
is shared because of copy-on-write feature.
How can I identify cow pages when it becomes cow? Is
there any feasible way to perform that?
BR,
Mauricio Lin.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
