On Tue, Oct 25, 2016 at 11:24:34AM +0800, Li Zhong wrote: > The core_idle_lock_held loops when the lock bit is held by others. > However, it is possible that after the lock bit is cleared, some one > else sees it first and sets the lock bit. And lwarx loads a value with > lock bit set, and the lock bit may be cleared in the following stwcx. > It is possible the first one is still executing in the critical section. > > This patch rechecks the lock bit after lwarx, and go back to loop if it > is set.
You're quite correct, in fact I posted almost exactly the same patch a few days ago... See http://patchwork.ozlabs.org/patch/684963/. Thanks, Paul.
