Re: [PATCH v2 1/2] paravirt/locks: use new static key for controlling call of virt_spin_lock()

From: Peter Zijlstra
Date: Wed Sep 06 2017 - 12:04:38 EST


On Wed, Sep 06, 2017 at 11:49:49AM -0400, Waiman Long wrote:
> > #define virt_spin_lock virt_spin_lock
> > static inline bool virt_spin_lock(struct qspinlock *lock)
> > {
> > + if (!static_branch_likely(&virt_spin_lock_key))
> > + return false;
> > if (!static_cpu_has(X86_FEATURE_HYPERVISOR))
> > return false;
> >

Now native has two NOPs instead of one. Can't we merge these two static
branches?