Re: [PATCH v2] core, x86: Add user return notifiers

H. Peter Anvin
2009-09-22T15:19:52Z

Ingo Molnar wrote:
> * Avi Kivity <avi@redhat.com> wrote:
>
>> On 09/19/2009 09:40 AM, Avi Kivity wrote:
>>> Add a general per-cpu notifier that is called whenever the kernel is
>>> about to return to userspace. The notifier uses a thread_info flag
>>> and existing checks, so there is no impact on user return or context
>>> switch fast paths.
>>>
>> Ingo/Peter?
>
> Would be nice to convert some existing open-coded return-to-user-space
> logic to this facility. One such candidate would be lockdep_sys_exit?
>
> Ingo

Sorry, limited bandwidth due to LinuxCon, but I like the concept, and
the previous (partial) patch was really clean. I agree with Ingo that
arch support so we can use this as a general facility would be nice, but
I don't consider that as a prerequisite for merging.

-hpa