On 6/4/24 21:27, Peter Zijlstra wrote:
> On Tue, Jun 04, 2024 at 09:36:08AM +0000, Bernd Schubert wrote:
>> On 6/4/24 11:26, Peter Zijlstra wrote:
>>> On Thu, May 30, 2024 at 04:37:29PM -0400, Josef Bacik wrote:
>>>> On Wed, May 29, 2024 at 08:00:50PM +0200, Bernd Schubert wrote:
>>>>> This is needed by fuse-over-io-uring to wake up the waiting
>>>>> application thread on the core it was submitted from.
>>>>> Avoiding core switching is actually a major factor for
>>>>> fuse performance improvements of fuse-over-io-uring.
>>>>>
>>>>> Signed-off-by: Bernd Schubert <bschubert@xxxxxxx>
>>>>> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
>>>>> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
>>>>> Cc: Andrei Vagin <avagin@xxxxxxxxxx>
>>>>
>>>> Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
>>>>
>>>> Probably best to submit this as a one-off so the sched guys can take it and it's
>>>> not in the middle of a fuse patchset they may be ignoring. Thanks,
>>>
>>> On its own its going to not be applied. Never merge an EXPORT without a
>>> user.
>>>
>>> As is, I don't have enough of the series to even see the user, so yeah,
>>> not happy :/
>>>
>>> And as hch said, this very much needs to be a GPL export.
>>
>> Sorry, accidentally done without the _GPL. What is the right way to get this merged?
>> First merge the entire fuse-io-uring series and then add on this? I already have these
>> optimization patches at the end of the series... The user for this is in the next patch
>
> Yeah, but you didn't send me the next patch, did you? So I have no
> clue.. :-)
>
> Anyway, if you could add a wee comment to __wake_up_con_current_cpu()
> along with the EXPORT_SYMBOL_GPL() that might be nice. I suppose you can
> copy paste from __wake_up() and then edit a wee bit.
>
>> [PATCH RFC v2 16/19] fuse: {uring} Wake requests on the the current cpu
>>
>> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
>> index c7fd3849a105..851c5fa99946 100644
>> --- a/fs/fuse/dev.c
>> +++ b/fs/fuse/dev.c
>> @@ -333,7 +333,10 @@ void fuse_request_end(struct fuse_req *req)
>> spin_unlock(&fc->bg_lock);
>> } else {
>> /* Wake up waiter sleeping in request_wait_answer() */
>> - wake_up(&req->waitq);
>> + if (fuse_per_core_queue(fc))
>> + __wake_up_on_current_cpu(&req->waitq, TASK_NORMAL, NULL);
>> + else
>> + wake_up(&req->waitq);
>> }
>>
>> if (test_bit(FR_ASYNC, &req->flags))
>
> Fair enough, although do we want a helper like wake_up() -- something
> like wake_up_on_current_cpu() ?
Thank you and yes sure!
I remove the patch and optimization from RFCv3, we first need to agree
on the taken approach and get that merged. Will send submit this
optimization immediately after.
Thanks,
Bernd
