The patch titled
Update page->order at an appropriate time when tracking PAGE_OWNER
has been added to the -mm tree. Its filename is
update-page-order-at-an-appropriate-time-when-tracking-page_owner.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: Update page->order at an appropriate time when tracking PAGE_OWNER
From: mel@xxxxxxxxx (Mel Gorman)
PAGE_OWNER tracks free pages by setting page->order to -1. However, it is
set during __free_pages() which is not the only free path as
__pagevec_free() and free_compound_page() do not go through __free_pages().
This leads to a situation where free pages are visible in /proc/page_owner
which is confusing and might be interpreted as a memory leak.
This patch sets page->owner when PageBuddy is set. It also prints a
warning to the kernel log if a free page is found that does not appear free
to PAGE_OWNER. This should be considered a fix to
page-owner-tracking-leak-detector.patch.
This only applies to -mm as PAGE_OWNER is not in mainline.
Signed-off-by: Mel Gorman <mel@xxxxxxxxx>
Acked-by: Andy Whitcroft <apw@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/proc/proc_misc.c | 8 ++++++++
mm/page_alloc.c | 6 +++---
2 files changed, 11 insertions(+), 3 deletions(-)
diff -puN fs/proc/proc_misc.c~update-page-order-at-an-appropriate-time-when-tracking-page_owner fs/proc/proc_misc.c
--- a/fs/proc/proc_misc.c~update-page-order-at-an-appropriate-time-when-tracking-page_owner
+++ a/fs/proc/proc_misc.c
@@ -769,8 +769,16 @@ read_page_owner(struct file *file, char
if (!pfn_valid(pfn))
continue;
page = pfn_to_page(pfn);
+
+ /* Catch situations where free pages have a bad ->order */
+ if (page->order >= 0 && PageBuddy(page))
+ printk(KERN_WARNING
+ "PageOwner info inaccurate for PFN %lu\n",
+ pfn);
+
if (page->order >= 0)
break;
+
next_idx++;
}
diff -puN mm/page_alloc.c~update-page-order-at-an-appropriate-time-when-tracking-page_owner mm/page_alloc.c
--- a/mm/page_alloc.c~update-page-order-at-an-appropriate-time-when-tracking-page_owner
+++ a/mm/page_alloc.c
@@ -308,6 +308,9 @@ static inline void set_page_order(struct
{
set_page_private(page, order);
__SetPageBuddy(page);
+#ifdef CONFIG_PAGE_OWNER
+ page->order = -1;
+#endif
}
static inline void rmv_page_order(struct page *page)
@@ -1726,9 +1729,6 @@ fastcall void __free_pages(struct page *
free_hot_page(page);
else
__free_pages_ok(page, order);
-#ifdef CONFIG_PAGE_OWNER
- page->order = -1;
-#endif
}
}
_
Patches currently in -mm which might be from mel@xxxxxxxxx are
x86_64-extract-helper-function-from-e820_register_active_regions.patch
add-a-bitmap-that-is-used-to-track-flags-affecting-a-block-of-pages.patch
add-__gfp_movable-for-callers-to-flag-allocations-from-high-memory-that-may-be-migrated.patch
split-the-free-lists-for-movable-and-unmovable-allocations.patch
choose-pages-from-the-per-cpu-list-based-on-migration-type.patch
add-a-configure-option-to-group-pages-by-mobility.patch
drain-per-cpu-lists-when-high-order-allocations-fail.patch
move-free-pages-between-lists-on-steal.patch
group-short-lived-and-reclaimable-kernel-allocations.patch
group-high-order-atomic-allocations.patch
do-not-group-pages-by-mobility-type-on-low-memory-systems.patch
bias-the-placement-of-kernel-pages-at-lower-pfns.patch
be-more-agressive-about-stealing-when-migrate_reclaimable-allocations-fallback.patch
fix-corruption-of-memmap-on-ia64-sparsemem-when-mem_section-is-not-a-power-of-2.patch
bias-the-location-of-pages-freed-for-min_free_kbytes-in-the-same-max_order_nr_pages-blocks.patch
remove-page_group_by_mobility.patch
dont-group-high-order-atomic-allocations.patch
fix-calculation-in-move_freepages_block-for-counting-pages.patch
breakout-page_order-to-internalh-to-avoid-special-knowledge-of-the-buddy-allocator.patch
do-not-depend-on-max_order-when-grouping-pages-by-mobility.patch
print-out-statistics-in-relation-to-fragmentation-avoidance-to-proc-pagetypeinfo.patch
remove-alloc_zeroed_user_highpage.patch
create-the-zone_movable-zone.patch
create-the-zone_movable-zone-fix.patch
allow-huge-page-allocations-to-use-gfp_high_movable.patch
allow-huge-page-allocations-to-use-gfp_high_movable-fix.patch
allow-huge-page-allocations-to-use-gfp_high_movable-fix-2.patch
handle-kernelcore=-generic.patch
lumpy-reclaim-v4.patch
lumpy-move-to-using-pfn_valid_within.patch
have-kswapd-keep-a-minimum-order-free-other-than-order-0.patch
have-kswapd-keep-a-minimum-order-free-other-than-order-0-fix.patch
only-check-absolute-watermarks-for-alloc_high-and-alloc_harder-allocations.patch
ext2-reservations.patch
add-__gfp_movable-for-callers-to-flag-allocations-from-high-memory-that-may-be-migrated-swap-prefetch.patch
rename-gfp_high_movable-to-gfp_highuser_movable-prefetch.patch
print-out-page_owner-statistics-in-relation-to-fragmentation-avoidance.patch
update-page-order-at-an-appropriate-time-when-tracking-page_owner.patch
add-debugging-aid-for-memory-initialisation-problems.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
