2 files changed, 19 insertions, 2 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index 7aa02def4666..de31af256207 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -218,8 +218,6 @@ config SPLIT_PTLOCK_CPUS
         int
         default "999999" if ARM && !CPU_CACHE_VIPT
         default "999999" if PARISC && !PA20
-        default "999999" if DEBUG_SPINLOCK || DEBUG_LOCK_ALLOC
-        default "999999" if !64BIT && GENERIC_LOCKBREAK
         default "4"
 
 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
diff --git a/mm/memory.c b/mm/memory.c
index d05c6b10e926..24ffae2a530e 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4270,3 +4270,22 @@ void copy_user_huge_page(struct page *dst, struct page *src,
         }
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
+
+#if USE_SPLIT_PTE_PTLOCKS
+bool __ptlock_alloc(struct page *page)
+{
+        spinlock_t *ptl;
+
+        ptl = kmalloc(sizeof(spinlock_t), GFP_KERNEL);
+        if (!ptl)
+                return false;
+        page->ptl = (unsigned long)ptl;
+        return true;
+}
+
+void __ptlock_free(struct page *page)
+{
+        if (sizeof(spinlock_t) > sizeof(page->ptl))
+                kfree((spinlock_t *)page->ptl);
+}
+#endif