From 94a59fb36ee91b3f977a9b914ec701efe40041de Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Wed, 9 Sep 2015 15:35:31 -0700 Subject: [PATCH] hwpoison: use page_cgroup_ino for filtering by memcg Hwpoison allows to filter pages by memory cgroup ino. Currently, it calls try_get_mem_cgroup_from_page to obtain the cgroup from a page and then its ino using cgroup_ino, but now we have a helper method for that, page_cgroup_ino, so use it instead. This patch also loosens the hwpoison memcg filter dependency rules - it makes it depend on CONFIG_MEMCG instead of CONFIG_MEMCG_SWAP, because hwpoison memcg filter does not require anything (nor it used to) from CONFIG_MEMCG_SWAP side. Signed-off-by: Vladimir Davydov Reviewed-by: Andres Lagar-Cavilla Cc: Minchan Kim Cc: Raghavendra K T Cc: Johannes Weiner Cc: Michal Hocko Cc: Greg Thelen Cc: Michel Lespinasse Cc: David Rientjes Cc: Pavel Emelyanov Cc: Cyrill Gorcunov Cc: Jonathan Corbet Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hwpoison-inject.c | 5 +---- mm/memory-failure.c | 16 ++-------------- 2 files changed, 3 insertions(+), 18 deletions(-) diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index aeba0edd6e44..9d26fd9fefe4 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -45,12 +45,9 @@ static int hwpoison_inject(void *data, u64 val) /* * do a racy check with elevated page count, to make sure PG_hwpoison * will only be set for the targeted owner (or on a free page). - * We temporarily take page lock for try_get_mem_cgroup_from_page(). * memory_failure() will redo the check reliably inside page lock. */ - lock_page(hpage); err = hwpoison_filter(hpage); - unlock_page(hpage); if (err) goto put_out; @@ -126,7 +123,7 @@ static int pfn_inject_init(void) if (!dentry) goto fail; -#ifdef CONFIG_MEMCG_SWAP +#ifdef CONFIG_MEMCG dentry = debugfs_create_u64("corrupt-filter-memcg", 0600, hwpoison_dir, &hwpoison_filter_memcg); if (!dentry) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index eeda6485e76c..95882692e747 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -130,27 +130,15 @@ static int hwpoison_filter_flags(struct page *p) * can only guarantee that the page either belongs to the memcg tasks, or is * a freed page. */ -#ifdef CONFIG_MEMCG_SWAP +#ifdef CONFIG_MEMCG u64 hwpoison_filter_memcg; EXPORT_SYMBOL_GPL(hwpoison_filter_memcg); static int hwpoison_filter_task(struct page *p) { - struct mem_cgroup *mem; - struct cgroup_subsys_state *css; - unsigned long ino; - if (!hwpoison_filter_memcg) return 0; - mem = try_get_mem_cgroup_from_page(p); - if (!mem) - return -EINVAL; - - css = &mem->css; - ino = cgroup_ino(css->cgroup); - css_put(css); - - if (ino != hwpoison_filter_memcg) + if (page_cgroup_ino(p) != hwpoison_filter_memcg) return -EINVAL; return 0; -- 2.20.1