mm: ptl is not bloated if it fits in pointer

Hugh Dickins
2013-12-16T09:04:39Z

It's silly to force the 64-bit CONFIG_GENERIC_LOCKBREAK architectures
to kmalloc eight bytes for an indirect page table lock: the lock needs
to fit in the space that a pointer to it would occupy, not into an int.

Signed-off-by: Hugh Dickins <hughd@google.com>
---

kernel/bounds.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- 3.13-rc4/kernel/bounds.c 2013-11-22 15:40:37.452192638 -0800
+++ linux/kernel/bounds.c 2013-12-15 14:34:36.304485959 -0800
@@ -22,6 +22,6 @@ void foo(void)
#ifdef CONFIG_SMP
DEFINE(NR_CPUS_BITS, ilog2(CONFIG_NR_CPUS));
#endif
- DEFINE(BLOATED_SPINLOCKS, sizeof(spinlock_t) > sizeof(int));
+ DEFINE(BLOATED_SPINLOCKS, sizeof(spinlock_t) > sizeof(spinlock_t *));
/* End of constants */
}