From: Jens Axboe <[email protected]>
To: Stefan Metzmacher <[email protected]>, [email protected]
Cc: [email protected], [email protected],
[email protected]
Subject: Re: [PATCHSET RFC 0/18] Remove kthread usage from io_uring
Date: Fri, 19 Feb 2021 16:51:59 -0700 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
On 2/19/21 4:44 PM, Stefan Metzmacher wrote:
> Hi Jens,
>
>> tldr - instead of using kthreads that assume the identity of the original
>> tasks for work that needs offloading to a thread, setup these workers as
>> threads of the original task.
>>
>> Here's a first cut of moving away from kthreads for io_uring. It passes
>> the test suite and various other testing I've done with it. It also
>> performs better, both for workloads actually using the async offload, but
>> also in general as we slim down structures and kill code from the hot path.
>>
>> The series is roughly split into these parts:
>>
>> - Patches 1-6, io_uring/io-wq prep patches
>> - Patches 7-8, Minor arch/kernel support
>> - Patches 9-15, switch from kthread to thread, remove state only needed
>> for kthreads
>> - Patches 16-18, remove now dead/unneeded PF_IO_WORKER restrictions
>>
>> Comments/suggestions welcome. I'm pretty happy with the series at this
>> point, and particularly with how we end up cutting a lot of code while
>> also unifying how sync vs async is presented.
>
> Thanks a lot! I was thinking hard about how to make all this easier to
> understand and perform better in order to have the whole context
> available natively for sendmsg/recvmsg, but also for the upcoming
> uring_cmd().
>
> And now all that code magically disappeared completely, wonderful :-)
Glad to hear you like the approach! Yes, this will help both
readability, performance, and maintainability. Pretty much a win all
around imho.
--
Jens Axboe
next prev parent reply other threads:[~2021-02-19 23:52 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-19 17:09 [PATCHSET RFC 0/18] Remove kthread usage from io_uring Jens Axboe
2021-02-19 17:09 ` [PATCH 01/18] io_uring: remove the need for relying on an io-wq fallback worker Jens Axboe
2021-02-19 20:25 ` Eric W. Biederman
2021-02-19 20:37 ` Jens Axboe
2021-02-22 13:46 ` Pavel Begunkov
2021-02-19 17:09 ` [PATCH 02/18] io-wq: don't create any IO workers upfront Jens Axboe
2021-02-19 17:09 ` [PATCH 03/18] io_uring: disable io-wq attaching Jens Axboe
2021-02-19 17:09 ` [PATCH 04/18] io-wq: get rid of wq->use_refs Jens Axboe
2021-02-19 17:09 ` [PATCH 05/18] io_uring: tie async worker side to the task context Jens Axboe
2021-02-20 8:11 ` Hao Xu
2021-02-20 14:38 ` Jens Axboe
2021-02-21 9:16 ` Hao Xu
2021-02-19 17:09 ` [PATCH 06/18] io-wq: don't pass 'wqe' needlessly around Jens Axboe
2021-02-19 17:09 ` [PATCH 07/18] arch: setup PF_IO_WORKER threads like PF_KTHREAD Jens Axboe
2021-02-19 22:21 ` Eric W. Biederman
2021-02-19 23:26 ` Jens Axboe
2021-02-19 17:10 ` [PATCH 08/18] kernel: treat PF_IO_WORKER like PF_KTHREAD for ptrace/signals Jens Axboe
2021-02-19 17:10 ` [PATCH 09/18] io-wq: fork worker threads from original task Jens Axboe
2021-03-04 12:23 ` Stefan Metzmacher
2021-03-04 13:05 ` Jens Axboe
2021-03-04 13:19 ` Stefan Metzmacher
2021-03-04 16:13 ` Stefan Metzmacher
2021-03-04 16:42 ` Jens Axboe
2021-03-04 17:09 ` Stefan Metzmacher
2021-03-04 17:32 ` Jens Axboe
2021-03-04 18:19 ` Jens Axboe
2021-03-04 18:56 ` Linus Torvalds
2021-03-04 19:19 ` Jens Axboe
2021-03-04 19:46 ` Linus Torvalds
2021-03-04 19:54 ` Jens Axboe
2021-03-04 20:00 ` Jens Axboe
2021-03-04 20:23 ` Jens Axboe
2021-03-04 20:50 ` Linus Torvalds
2021-03-04 20:54 ` Jens Axboe
2021-03-05 19:16 ` Eric W. Biederman
2021-03-05 19:00 ` Eric W. Biederman
2021-02-19 17:10 ` [PATCH 10/18] io-wq: worker idling always returns false Jens Axboe
2021-02-19 17:10 ` [PATCH 11/18] io_uring: remove any grabbing of context Jens Axboe
2021-02-19 17:10 ` [PATCH 12/18] io_uring: remove io_identity Jens Axboe
2021-02-19 17:10 ` [PATCH 13/18] io-wq: only remove worker from free_list, if it was there Jens Axboe
2021-02-19 17:10 ` [PATCH 14/18] io-wq: make io_wq_fork_thread() available to other users Jens Axboe
2021-02-19 17:10 ` [PATCH 15/18] io_uring: move SQPOLL thread io-wq forked worker Jens Axboe
2021-02-19 17:10 ` [PATCH 16/18] Revert "proc: don't allow async path resolution of /proc/thread-self components" Jens Axboe
2021-02-19 17:10 ` [PATCH 17/18] Revert "proc: don't allow async path resolution of /proc/self components" Jens Axboe
2021-02-19 17:10 ` [PATCH 18/18] net: remove cmsg restriction from io_uring based send/recvmsg calls Jens Axboe
2021-02-19 23:44 ` [PATCHSET RFC 0/18] Remove kthread usage from io_uring Stefan Metzmacher
2021-02-19 23:51 ` Jens Axboe [this message]
2021-02-21 5:04 ` Linus Torvalds
2021-02-21 21:22 ` Jens Axboe
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