On Tue, Jan 21, 2014 at 11:35:53PM +0000, Tim Chen wrote: > From: Waiman Long <Waiman.Long@xxxxxx> > > This patch corrects the way memory barriers are used in the MCS lock > with smp_load_acquire and smp_store_release fucnctions. The previous > barriers could leak critical sections if mcs lock is used by itself. > It is not a problem when mcs lock is embedded in mutex but will be an > issue when the mcs_lock is used elsewhere. > > The patch removes the incorrect barriers and put in correct > barriers with the pair of functions smp_load_acquire and smp_store_release. > > Suggested-by: Michel Lespinasse <walken@xxxxxxxxxx> > Reviewed-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Waiman Long <Waiman.Long@xxxxxx> > Signed-off-by: Jason Low <jason.low2@xxxxxx> > Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> > --- > kernel/locking/mutex.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) Reviewed-by: Will Deacon <will.deacon@xxxxxxx> Will -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>