hwpoison: use page_cgroup_ino for filtering by memcg (94a59fb3) · Commits · 戴 / test

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 <vdavydov@parallels.com> Reviewed-by:

Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

mm/hwpoison-inject.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -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)

mm/memory-failure.c

+2 −14

Original line number	Diff line number	Diff line
		@@ -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;

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