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

From: Ingo Molnar
Date: Thu Jun 16 2011 - 18:59:17 EST



* Andi Kleen <ak@xxxxxxxxxxxxxxx> 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
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