On Mon May 8, 2023 at 12:01 PM AEST, Rohan McLure wrote: > Use a compiler barrier to enforce that all fields of a new struct qnode > be written to (especially the lock value) before publishing the qnode to > the waitqueue.
publish_tail_cpu is the release barrier for this and includes the memory clobber there. Can we annotate that instead? Thanks, Nick > > Signed-off-by: Rohan McLure <rmcl...@linux.ibm.com> > --- > arch/powerpc/lib/qspinlock.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/powerpc/lib/qspinlock.c b/arch/powerpc/lib/qspinlock.c > index 579290d55abf..d548001a86be 100644 > --- a/arch/powerpc/lib/qspinlock.c > +++ b/arch/powerpc/lib/qspinlock.c > @@ -567,6 +567,10 @@ static __always_inline void > queued_spin_lock_mcs_queue(struct qspinlock *lock, b > node->cpu = smp_processor_id(); > node->yield_cpu = -1; > node->locked = 1; > + /* > + * Assign all attributes of a node before it can be published. > + */ > + barrier(); > > tail = encode_tail_cpu(node->cpu); > > -- > 2.37.2
