Re: [RFC patch 02/15] x86/entry: Remove _TIF_NOHZ from _TIF_WORK_SYSCALL_ENTRY

[Thomas Gleixner]

On Fri, 20 Sep 2019, Andy Lutomirski wrote:

> On Thu, Sep 19, 2019 at 8:09 AM Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> >
> > Evaluating _TIF_NOHZ to decide whether to use the slow syscall entry path
> > is not only pointless, it's actually counterproductive:
> >
> >  1) Context tracking code is invoked unconditionally before that flag is
> >     evaluated.
> >
> >  2) If the flag is set the slow path is invoked for nothing due to #1
> 
> Can we also get rid of TIF_NOHZ on x86?

If we make the usage in context_tracking_cpu_set() conditional.

Thanks,

	tglx