From: Hao Xu <haoxu@linux.alibaba.com>
To: Bixuan Cui <cuibixuan@huawei.com>,
linux-kernel@vger.kernel.org, io-uring@vger.kernel.org
Cc: axboe@kernel.dk, asml.silence@gmail.com,
Joseph Qi <joseph.qi@linux.alibaba.com>
Subject: Re: [PATCH -next] io-wq: Remove duplicate code in io_workqueue_create()
Date: Sun, 12 Sep 2021 23:36:01 +0800 [thread overview]
Message-ID: <49d9bb13-a7b3-48b5-20ef-d3b72052f92b@linux.alibaba.com> (raw)
In-Reply-To: <20210911085847.34849-1-cuibixuan@huawei.com>
在 2021/9/11 下午4:58, Bixuan Cui 写道:
> While task_work_add() in io_workqueue_create() is true,
> then duplicate code is executed:
>
> -> clear_bit_unlock(0, &worker->create_state);
> -> io_worker_release(worker);
> -> atomic_dec(&acct->nr_running);
> -> io_worker_ref_put(wq);
> -> return false;
>
> -> clear_bit_unlock(0, &worker->create_state); // back to io_workqueue_create()
> -> io_worker_release(worker);
> -> kfree(worker);
>
> The io_worker_release() and clear_bit_unlock() are executed twice.
>
> Fixes: 3146cba99aa2 ("io-wq: make worker creation resilient against signals")
> Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
> ---
> fs/io-wq.c | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/fs/io-wq.c b/fs/io-wq.c
> index 6c55362c1f99..95d0eaed7c00 100644
> --- a/fs/io-wq.c
> +++ b/fs/io-wq.c
> @@ -329,8 +329,10 @@ static bool io_queue_worker_create(struct io_worker *worker,
>
> init_task_work(&worker->create_work, func);
> worker->create_index = acct->index;
> - if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL))
> + if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) {
> + clear_bit_unlock(0, &worker->create_state);
> return true;
> + }
> clear_bit_unlock(0, &worker->create_state);
> fail_release:
> io_worker_release(worker);
> @@ -723,11 +725,8 @@ static void io_workqueue_create(struct work_struct *work)
> struct io_worker *worker = container_of(work, struct io_worker, work);
> struct io_wqe_acct *acct = io_wqe_get_acct(worker);
>
> - if (!io_queue_worker_create(worker, acct, create_worker_cont)) {
> - clear_bit_unlock(0, &worker->create_state);
> - io_worker_release(worker);
> + if (!io_queue_worker_create(worker, acct, create_worker_cont))
> kfree(worker);
> - }
> }
>
> static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index)
>
AFAIK, this looks reasonable for me.
next prev parent reply other threads:[~2021-09-12 15:36 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-11 8:58 [PATCH -next] io-wq: Remove duplicate code in io_workqueue_create() Bixuan Cui
2021-09-12 15:36 ` Hao Xu [this message]
2021-09-15 18:12 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=49d9bb13-a7b3-48b5-20ef-d3b72052f92b@linux.alibaba.com \
--to=haoxu@linux.alibaba.com \
--cc=asml.silence@gmail.com \
--cc=axboe@kernel.dk \
--cc=cuibixuan@huawei.com \
--cc=io-uring@vger.kernel.org \
--cc=joseph.qi@linux.alibaba.com \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).