Recently lockless_dereference() was added which can be used in place of hard-coding smp_read_barrier_depends(). The following PATCH makes the change.
Signed-off-by: Pranith Kumar <[email protected]> --- mm/ksm.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/mm/ksm.c b/mm/ksm.c index d247efa..a67de79 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -542,15 +542,14 @@ static struct page *get_ksm_page(struct stable_node *stable_node, bool lock_it) expected_mapping = (void *)stable_node + (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM); again: - kpfn = ACCESS_ONCE(stable_node->kpfn); - page = pfn_to_page(kpfn); - /* * page is computed from kpfn, so on most architectures reading * page->mapping is naturally ordered after reading node->kpfn, * but on Alpha we need to be more careful. */ - smp_read_barrier_depends(); + kpfn = lockless_dereference(stable_node->kpfn); + page = pfn_to_page(kpfn); + if (ACCESS_ONCE(page->mapping) != expected_mapping) goto stale; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
