diff options
| author | Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> | 2011-03-23 16:42:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-23 19:46:25 -0700 |
| commit | f212ad7cf9c73f8a7fa160e223dcb3f074441a72 (patch) | |
| tree | 95789ef7ce662e86a3e4aded5dfb97c51dc7b0a0 /mm/memcontrol.c | |
| parent | af4a662144884a7dbb19acbef70878b3b955f928 (diff) | |
memcg: add memcg sanity checks at allocating and freeing pages
Add checks at allocating or freeing a page whether the page is used (iow,
charged) from the view point of memcg.
This check may be useful in debugging a problem and we did similar checks
before the commit 52d4b9ac(memcg: allocate all page_cgroup at boot).
This patch adds some overheads at allocating or freeing memory, so it's
enabled only when CONFIG_DEBUG_VM is enabled.
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3a2d54bdf07..0356cb6c950 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3046,6 +3046,52 @@ int mem_cgroup_shmem_charge_fallback(struct page *page, return ret; } +#ifdef CONFIG_DEBUG_VM +static struct page_cgroup *lookup_page_cgroup_used(struct page *page) +{ + struct page_cgroup *pc; + + pc = lookup_page_cgroup(page); + if (likely(pc) && PageCgroupUsed(pc)) + return pc; + return NULL; +} + +bool mem_cgroup_bad_page_check(struct page *page) +{ + if (mem_cgroup_disabled()) + return false; + + return lookup_page_cgroup_used(page) != NULL; +} + +void mem_cgroup_print_bad_page(struct page *page) +{ + struct page_cgroup *pc; + + pc = lookup_page_cgroup_used(page); + if (pc) { + int ret = -1; + char *path; + + printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", + pc, pc->flags, pc->mem_cgroup); + + path = kmalloc(PATH_MAX, GFP_KERNEL); + if (path) { + rcu_read_lock(); + ret = cgroup_path(pc->mem_cgroup->css.cgroup, + path, PATH_MAX); + rcu_read_unlock(); + } + + printk(KERN_CONT "(%s)\n", + (ret < 0) ? "cannot get the path" : path); + kfree(path); + } +} +#endif + static DEFINE_MUTEX(set_limit_mutex); static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |