num_poisoned_pages counts up the number of pages isolated by memory
errors. But for thp, only one subpage is isolated because memory error
handler splits it, so it's wrong to add (1 << compound_trans_order).
[akpm@linux-foundation.org: tweak comment]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
return 0;
}
- nr_pages = 1 << compound_trans_order(hpage);
+ /*
+ * Currently errors on hugetlbfs pages are measured in hugepage units,
+ * so nr_pages should be 1 << compound_order. OTOH when errors are on
+ * transparent hugepages, they are supposed to be split and error
+ * measurement is done in normal page units. So nr_pages should be one
+ * in this case.
+ */
+ if (PageHuge(p))
+ nr_pages = 1 << compound_order(hpage);
+ else /* normal page or thp */
+ nr_pages = 1;
atomic_long_add(nr_pages, &num_poisoned_pages);
/*