teach /proc/$pid/numa_maps about transparent hugepages

This is modeled after the smaps code.

It detects transparent hugepages and then does a single gather_stats()
for the page as a whole.  This has two benifits:
 1. It is more efficient since it does many pages in a single shot.
 2. It does not have to break down the huge page.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dave Hansen 2011-09-20 15:19:41 -07:00 committed by Linus Torvalds
parent 3200a8aaab
commit 32ef43848f

View file

@ -936,6 +936,26 @@ static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
pte_t *pte;
md = walk->private;
spin_lock(&walk->mm->page_table_lock);
if (pmd_trans_huge(*pmd)) {
if (pmd_trans_splitting(*pmd)) {
spin_unlock(&walk->mm->page_table_lock);
wait_split_huge_page(md->vma->anon_vma, pmd);
} else {
pte_t huge_pte = *(pte_t *)pmd;
struct page *page;
page = can_gather_numa_stats(huge_pte, md->vma, addr);
if (page)
gather_stats(page, md, pte_dirty(huge_pte),
HPAGE_PMD_SIZE/PAGE_SIZE);
spin_unlock(&walk->mm->page_table_lock);
return 0;
}
} else {
spin_unlock(&walk->mm->page_table_lock);
}
orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
do {
struct page *page = can_gather_numa_stats(*pte, md->vma, addr);