From: Jens Axboe <[email protected]>
To: Pavel Begunkov <[email protected]>,
Stefano Garzarella <[email protected]>
Cc: [email protected], [email protected]
Subject: Re: Are CAP_SYS_ADMIN and CAP_SYS_NICE still needed for SQPOLL?
Date: Thu, 25 Mar 2021 08:02:45 -0600 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
On 3/25/21 7:44 AM, Pavel Begunkov wrote:
> On 25/03/2021 11:33, Stefano Garzarella wrote:
>> Hi Jens, Hi Pavel,
>> I was taking a look at the new SQPOLL handling with io_thread instead of kthread. Great job! Really nice feature that maybe can be reused also in other scenarios (e.g. vhost).
>>
>> Regarding SQPOLL, IIUC these new threads are much closer to user threads, so is there still a need to require CAP_SYS_ADMIN and CAP_SYS_NICE to enable SQPOLL?
>
> Hmm, good question. If there are under same cgroup (should be in
> theory), and if we add more scheduling points (i.e. need_resched()), and
> don't see a reason why not. Jens?
>
> Better not right away though. IMHO it's safer to let the change settle
> down for some time.
Yes, agree on both counts - we are not going to need elevated privileges
going forward, but I'd also rather defer making that change until 5.13
so we have a bit more time on the current (new) base first.
--
Jens Axboe
next prev parent reply other threads:[~2021-03-25 14:03 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-25 11:33 Are CAP_SYS_ADMIN and CAP_SYS_NICE still needed for SQPOLL? Stefano Garzarella
2021-03-25 13:44 ` Pavel Begunkov
2021-03-25 14:02 ` Jens Axboe [this message]
2021-03-25 14:09 ` Stefano Garzarella
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