From 7ea8574e5fa31f43d8098a028f12ba6a9c9f3530 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Fri, 29 Aug 2014 15:18:42 -0700 Subject: [PATCH] hugetlb_cgroup: use lockdep_assert_held rather than spin_is_locked spin_lock may be an empty struct for !SMP configurations and so arch_spin_is_locked may return unconditional 0 and trigger the VM_BUG_ON even when the lock is held. Replace spin_is_locked by lockdep_assert_held. We will not BUG anymore but it is questionable whether crashing makes a lot of sense in the uncharge path. Uncharge happens after the last page reference was released so nobody should touch the page and the function doesn't update any shared state except for res counter which uses synchronization of its own. Signed-off-by: Michal Hocko Reviewed-by: Aneesh Kumar K.V Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb_cgroup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c index 9eebfadeeee1..a67c26e0f360 100644 --- a/mm/hugetlb_cgroup.c +++ b/mm/hugetlb_cgroup.c @@ -217,7 +217,7 @@ void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages, if (hugetlb_cgroup_disabled()) return; - VM_BUG_ON(!spin_is_locked(&hugetlb_lock)); + lockdep_assert_held(&hugetlb_lock); h_cg = hugetlb_cgroup_from_page(page); if (unlikely(!h_cg)) return;