Re: [PATCH] perf/x86/intel: Avoid unnecessary reallocations of memory allocated in cpu hotplug prepare state

[Peter Zijlstra]

On Tue, Dec 18, 2018 at 12:16:37PM +0100, Sebastian Andrzej Siewior wrote:
> On 2018-12-18 12:02:09 [+0100], Peter Zijlstra wrote:
> > On Tue, Dec 18, 2018 at 06:30:33PM +0800, zhe.he@xxxxxxxxxxxxx wrote:
> > > Besides, in preempt-rt full mode, the freeing can happen in atomic context and
> > > thus cause the following BUG.
> > 
> > Hurm, I though we fixed all those long ago..
> > 
> > And no, the patch is horrible; that's what we have things like
> > x86_pmu::cpu_dead() for.
> 
> ehm, you say we keep memory allocation +free on CPU up/down?

Sure, why not?