From: Tejun Heo <tj@kernel.org>
To: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] device core: Remove deprecated create_singlethread_workqueue
Date: Wed, 31 Aug 2016 10:24:16 -0400 [thread overview]
Message-ID: <20160831142416.GK12660@htj.duckdns.org> (raw)
In-Reply-To: <20160830171534.GA1917@Karyakshetra>
On Tue, Aug 30, 2016 at 10:45:34PM +0530, Bhaktipriya Shridhar wrote:
> The workqueue "deferred_wq" queues a single work item
> &deferred_probe_work and hence doesn't require ordering.
> It is involved in probing devices and is not being used on a memory
> reclaim path. Hence, it has been converted to use system_wq.
>
> System workqueues have been able to handle high level of concurrency
> for a long time now and hence it's not required to have a singlethreaded
> workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue
> created with create_singlethread_workqueue(), system_wq allows multiple
> work items to overlap executions even on the same CPU; however, a
> per-cpu workqueue doesn't have any CPU locality or global ordering
> guarantee unless the target CPU is explicitly specified and thus the
> increase of local concurrency shouldn't make any difference.
>
> The work item has been flushed in driver_probe_done() to ensure that
> there are no pending tasks while disconnecting the driver.
>
> Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Thanks.
--
tejun
prev parent reply other threads:[~2016-08-31 14:24 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-30 17:15 [PATCH] device core: Remove deprecated create_singlethread_workqueue Bhaktipriya Shridhar
2016-08-31 14:24 ` Tejun Heo [this message]
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=20160831142416.GK12660@htj.duckdns.org \
--to=tj@kernel.org \
--cc=bhaktipriya96@gmail.com \
--cc=gregkh@linuxfoundation.org \
--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).