OpenVZ Forum


Home » Mailing lists » Devel » [PATCH v4 00/25] kmem limitation for memcg
[PATCH v4 16/25] don't do __ClearPageSlab before freeing slab page. [message #46834 is a reply to message #46818] Mon, 18 June 2012 10:28 Go to previous messageGo to previous message
Glauber Costa is currently offline  Glauber Costa
Messages: 916
Registered: October 2011
Senior Member
This will give the oportunity to the page allocator to
determine that a given page was previously a slab page, and
take action accordingly.

If memcg kmem is present, this means that that page needs to
be unaccounted. The page allocator will now have the responsibility
to clear that bit upon free_pages().

It is not uncommon to have the page allocator to check page flags.
Mlock flag, for instance, is checked pervasively all over the place.
So I hope this is okay for the slab as well.

Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: Pekka Enberg <penberg@cs.helsinki.fi>
CC: Michal Hocko <mhocko@suse.cz>
CC: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
CC: Johannes Weiner <hannes@cmpxchg.org>
CC: Suleiman Souhlal <suleiman@google.com>
---
mm/page_alloc.c | 5 ++++-
mm/slab.c | 5 -----
mm/slob.c | 1 -
mm/slub.c | 1 -
4 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 918330f..a884a9c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -697,8 +697,10 @@ static bool free_pages_prepare(struct page *page, unsigned int order)

if (PageAnon(page))
page->mapping = NULL;
- for (i = 0; i < (1 << order); i++)
+ for (i = 0; i < (1 << order); i++) {
+ __ClearPageSlab(page + i);
bad += free_pages_check(page + i);
+ }
if (bad)
return false;

@@ -2505,6 +2507,7 @@ EXPORT_SYMBOL(get_zeroed_page);
void __free_pages(struct page *page, unsigned int order)
{
if (put_page_testzero(page)) {
+ __ClearPageSlab(page);
if (order == 0)
free_hot_cold_page(page, 0);
else
diff --git a/mm/slab.c b/mm/slab.c
index c548666..e537406 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1795,11 +1795,6 @@ static void kmem_freepages(struct kmem_cache *cachep, void *addr)
else
sub_zone_page_state(page_zone(page),
NR_SLAB_UNRECLAIMABLE, nr_freed);
- while (i--) {
- BUG_ON(!PageSlab(page));
- __ClearPageSlab(page);
- page++;
- }
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += nr_freed;
free_pages((unsigned long)addr, cachep->gfporder);
diff --git a/mm/slob.c b/mm/slob.c
index 61b1845..b03d65e 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -360,7 +360,6 @@ static void slob_free(void *block, int size)
if (slob_page_free(sp))
clear_slob_page_free(sp);
spin_unlock_irqrestore(&slob_lock, flags);
- __ClearPageSlab(sp);
reset_page_mapcount(sp);
slob_free_pages(b, 0);
return;
diff --git a/mm/slub.c b/mm/slub.c
index e685cfa..69c5677 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1399,7 +1399,6 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
-pages);

- __ClearPageSlab(page);
reset_page_mapcount(page);
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += pages;
--
1.7.10.2
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: [PATCH] provide a common place for initcall processing in kmem_cache
Next Topic: [PATCH] SUNRPC: return negative value in case rpcbind client creation error
Goto Forum:
  


Current Time: Wed Aug 27 19:17:12 GMT 2025

Total time taken to generate the page: 0.21169 seconds