x86, olpc: Add comment about implicit optimization barrier

Signed-off-by: Andres Salomon <dilinger@queued.net>
Cc: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <20100618174653.7755a39a@dev.queued.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/kernel/olpc_ofw.c b/arch/x86/kernel/olpc_ofw.c
index 469ee4384295..f5d499fbe74f 100644
--- a/arch/x86/kernel/olpc_ofw.c
+++ b/arch/x86/kernel/olpc_ofw.c
@@ -35,6 +35,8 @@ void __init setup_olpc_ofw_pgd(void)
 
         /* install OFW's PDE permanently into the kernel's pgtable */
         set_pgd(&swapper_pg_dir[OLPC_OFW_PDE_NR], *ofw_pde);
+        /* implicit optimization barrier here due to uninline function return */
+
         early_iounmap(base, sizeof(olpc_ofw_pgd) * PTRS_PER_PGD);
 }