# Re: \[PATCH v9 00/13\] support "task\_isolation" mode for nohz\_full

- From: Chris Metcalf \<hidden\>
- Date: 2016-01-13 21:20:23 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2016/01/4659964
- Thread: https://ratatoskr.run/linux-api/2016/01/4652291/t.md

```text
On 01/13/2016 05:44 AM, Ingo Molnar wrote:
> * Chris Metcalf [ref] wrote:
>
>> (Adding Mark to cc's)
>>
>> On 01/12/2016 05:07 AM, Will Deacon wrote:
>>> On Mon, Jan 11, 2016 at 04:15:50PM -0500, Chris Metcalf wrote:
>>>> Ping!  There has been no substantive feedback to this version of
>>>> the patch in the week since I posted it, which optimistically suggests
>>>> to me that people may be satisfied with it.  If that's true, Frederic,
>>>> I assume this would be pulled into your tree?
>>>>
>>>> I have slightly updated the v9 patch series since this posting:
>>>>
>>>> [...]
>>>>
>>>> - Incorporated Mark Rutland's changes to convert arm64
>>>>    assembly to C code instead of using my own version.
>>> Please avoid queuing these patches -- the first is already in the arm64
>>> queue for 4.5 and the second was found to introduce a substantial
>>> performance regression on the syscall entry/exit path. I think Mark had
>>> an updated version to address that, so it would be easier not to have
>>> an old version sitting in some other queue!
>> I am not formally queueing them anywhere (like linux-next), though
>> now that you mention it, that's a pretty good idea - I'll talk to Steven
>> about that, assuming this merge window closes without the task
>> isolation stuff going in.
> NAK. Given the controversy, no way should this stuff go outside the primary trees
> it affects: the scheduler, timer, irq, etc. trees.

Fair enough.  I'll plan to do v10 once the merge window closes.

Mark, let me know when/if you get a new version of the de-asm stuff
for do_notify_resume() - thanks.  Or, would it be helpful if I worked up
the option I suggested, where we check the thread_info flags in the
assembly code before calling out to the new loop in do_notify_resume()?

-- 
Chris Metcalf, EZChip Semiconductor
http://www.ezchip.com

```