[PATCH 1/2] kernel/smp: Explicitly inline cds_lock helpers

Davidlohr Bueso
2016-03-10T01:56:33Z

From: Davidlohr Bueso <dave@stgolabs.net>

While the compiler tends to already to it for us (except for
cds_unlock), make it explicit. These helpers mainly deal with
the ->flags, are short-lived and can be called, for example,
from smp_call_function_many().

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
kernel/smp.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/smp.c b/kernel/smp.c
index 822ffb1ada3f..c91e00178f8f 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -105,13 +105,13 @@ void __init call_function_init(void)
* previous function call. For multi-cpu calls its even more interesting
* as we'll have to ensure no other cpu is observing our csd.
*/
-static void csd_lock_wait(struct call_single_data *csd)
+static __always_inline void csd_lock_wait(struct call_single_data *csd)
{
while (smp_load_acquire(&csd->flags) & CSD_FLAG_LOCK)
cpu_relax();
}

-static void csd_lock(struct call_single_data *csd)
+static __always_inline void csd_lock(struct call_single_data *csd)
{
csd_lock_wait(csd);
csd->flags |= CSD_FLAG_LOCK;
@@ -124,7 +124,7 @@ static void csd_lock(struct call_single_data *csd)
smp_wmb();
}

-static void csd_unlock(struct call_single_data *csd)
+static __always_inline void csd_unlock(struct call_single_data *csd)
{
WARN_ON(!(csd->flags & CSD_FLAG_LOCK));

--
2.1.4