mm: define USE_SPLIT_PTLOCKS rather than repeating expression
Define USE_SPLIT_PTLOCKS as a constant expression rather than repeating
"NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS" all over the place.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 72a15dc..4194bf8 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -919,7 +919,7 @@
}
#endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */
-#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
+#if USE_SPLIT_PTLOCKS
/*
* We tuck a spinlock to guard each pagetable page into its struct page,
* at page->private, with BUILD_BUG_ON to make sure that this will not
@@ -932,14 +932,14 @@
} while (0)
#define pte_lock_deinit(page) ((page)->mapping = NULL)
#define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));})
-#else
+#else /* !USE_SPLIT_PTLOCKS */
/*
* We use mm->page_table_lock to guard all pagetable pages of the mm.
*/
#define pte_lock_init(page) do {} while (0)
#define pte_lock_deinit(page) do {} while (0)
#define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;})
-#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
+#endif /* USE_SPLIT_PTLOCKS */
static inline void pgtable_page_ctor(struct page *page)
{