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hugetlb_cgroup: use lockdep_assert_held rather than spin_is_locked

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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 <mhocko@suse.cz>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michal Hocko 2014-08-29 15:18:42 -07:00 committed by Linus Torvalds
parent 137f8cff50
commit 7ea8574e5f
1 changed files with 1 additions and 1 deletions
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2
mm/hugetlb_cgroup.c
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@ -217,7 +217,7 @@ void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
if (hugetlb_cgroup_disabled()) if (hugetlb_cgroup_disabled())
return; return;
VM_BUG_ON(!spin_is_locked(&hugetlb_lock)); lockdep_assert_held(&hugetlb_lock);
h_cg = hugetlb_cgroup_from_page(page); h_cg = hugetlb_cgroup_from_page(page);
if (unlikely(!h_cg)) if (unlikely(!h_cg))
return; return;