Re: [GIT PULL] Re: REGRESSION: Performance regressions from switching anon_vma->lock to mutex

Ingo Molnar
2011-06-16T22:59:07Z

* Andi Kleen <ak@linux.intel.com> wrote:

> > There's a crazy solution for that: the idle thread could process
> > RCU callbacks carefully, as if it was running user-space code.
>
> In Ben's kernel NFS server case the system may not be idle.

An always-100%-busy NFS server is very unlikely, but even in the
hypothetical case a kernel NFS server is really performing system
calls from a kernel thread in essence. If it doesn't do it explicitly
then its main loop can easily include a "check RCU callbacks" call.

Thanks,

Ingo