dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

mm: allocate kernel pages to the right memcg 

When a process tries to allocate a page with the __GFP_KMEMCG flag, the
page allocator will call the corresponding memcg functions to validate
the allocation.  Tasks in the root memcg can always proceed.

To avoid adding markers to the page - and a kmem flag that would
necessarily follow, as much as doing page_cgroup lookups for no reason,
whoever is marking its allocations with __GFP_KMEMCG flag is responsible
for telling the page allocator that this is such an allocation at
free_pages() time.  This is done by the invocation of
__free_accounted_pages() and free_accounted_pages().

Signed-off-by: Glauber Costa <glommer@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: JoonSoo Kim <js1304@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Glauber Costa 2012-12-18 14:22:00 -08:00 committed by Linus Torvalds
parent 7ae1e1d0f8
commit 6a1a0d3b62
2 changed files with 38 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
include/linux/gfp.h
View File

@ -367,6 +367,9 @@ extern void free_pages(unsigned long addr, unsigned int order);
extern void free_hot_cold_page(struct page *page, int cold);
extern void free_hot_cold_page_list(struct list_head *list, int cold);
extern void __free_memcg_kmem_pages(struct page *page, unsigned int order);
extern void free_memcg_kmem_pages(unsigned long addr, unsigned int order);
#define __free_page(page) __free_pages((page), 0)
#define free_page(addr) free_pages((addr), 0)

35
mm/page_alloc.c
View File

@ -2612,6 +2612,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
int migratetype = allocflags_to_migratetype(gfp_mask);
unsigned int cpuset_mems_cookie;
int alloc_flags = ALLOC_WMARK_LOW|ALLOC_CPUSET;
struct mem_cgroup *memcg = NULL;
gfp_mask &= gfp_allowed_mask;
@ -2630,6 +2631,13 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
if (unlikely(!zonelist->_zonerefs->zone))
return NULL;
/*
* Will only have any effect when __GFP_KMEMCG is set. This is
* verified in the (always inline) callee
*/
if (!memcg_kmem_newpage_charge(gfp_mask, &memcg, order))
return NULL;
retry_cpuset:
cpuset_mems_cookie = get_mems_allowed();
@ -2665,6 +2673,8 @@ out:
if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page))
goto retry_cpuset;
memcg_kmem_commit_charge(page, memcg, order);
return page;
}
EXPORT_SYMBOL(__alloc_pages_nodemask);
@ -2717,6 +2727,31 @@ void free_pages(unsigned long addr, unsigned int order)
EXPORT_SYMBOL(free_pages);
/*
* __free_memcg_kmem_pages and free_memcg_kmem_pages will free
* pages allocated with __GFP_KMEMCG.
*
* Those pages are accounted to a particular memcg, embedded in the
* corresponding page_cgroup. To avoid adding a hit in the allocator to search
* for that information only to find out that it is NULL for users who have no
* interest in that whatsoever, we provide these functions.
*
* The caller knows better which flags it relies on.
*/
void __free_memcg_kmem_pages(struct page *page, unsigned int order)
{
memcg_kmem_uncharge_pages(page, order);
__free_pages(page, order);
}
void free_memcg_kmem_pages(unsigned long addr, unsigned int order)
{
if (addr != 0) {
VM_BUG_ON(!virt_addr_valid((void *)addr));
__free_memcg_kmem_pages(virt_to_page((void *)addr), order);
}
}
static void *make_alloc_exact(unsigned long addr, unsigned order, size_t size)
{
if (addr) {