From: qiaozhou <qiaozhou@asrmicro.com>
To: <tj@kernel.org>, <linux-pm@vger.kernel.org>,
Wang Wilbur <wilburwang@asrmicro.com>,
Wu Gang <gangwu@asrmicro.com>, <linux-kernel@vger.kernel.org>
Subject: [Question] about patch: don't use [delayed_]work_pending()
Date: Thu, 1 Sep 2016 17:09:36 +0800 [thread overview]
Message-ID: <d2501c4c-8e7b-bea3-1b01-000b36b5dfe9@asrmicro.com> (raw)
Hi Tejun,
I have a question related with below patch, and need your suggestion.
In our system, we do cpu clock init in of_clk_init path, and use pm qos
to maintain cpu/cci clock. Firstly we init a CCI_CLK_QOS and set a
default value, then update CCI_CLK_QOS to limit CCI min frequency
according to current cpu frequency. Before calling
pm_qos_update_request, irq is disabled, but after the calling, irq is
enabled in cancel_delayed_work_sync, which causes some inconvenience
before Before this patch is applied, it checks pending work and won't do
cancel_delayed_work_sync in this boot up phase.
The simple calling sequence is like this:
start_kernel -> of_clk_init -> cpu_clk_init -> pm_qos_add_request(xx,
default_value),
then pm_qos_update_request.
I don't know whether it's meaningful to still check pending work here,
or it's not suggested to use pm_qos_update_request in this early boot up
phase. Could you help to share some opinions? (I can fix this issue by
adding the current qos value directly instead of default value, though.)
Thanks a lot.
commit ed1ac6e91a3ff7c561008ba57747cd6cbc49385e
Author: Tejun Heo <tj@kernel.org>
Date: Fri Jan 11 13:37:33 2013 +0100
PM: don't use [delayed_]work_pending()
There's no need to test whether a (delayed) work item is pending
before queueing, flushing or cancelling it, so remove work_pending()
tests used in those cases.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
...
@@ -359,8 +359,7 @@ void pm_qos_update_request(struct pm_qos_request *req,
return;
}
- if (delayed_work_pending(&req->work))
- cancel_delayed_work_sync(&req->work);
+ cancel_delayed_work_sync(&req->work);
...
Best Regards
Qiao
next reply other threads:[~2016-09-01 9:25 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-01 9:09 qiaozhou [this message]
2016-09-01 18:45 ` [Question] about patch: don't use [delayed_]work_pending() Tejun Heo
2016-09-02 1:17 ` qiaozhou
2016-09-02 13:50 ` Tejun Heo
2016-09-02 14:21 ` Tejun Heo
2016-09-03 15:27 ` qiaozhou
2016-09-05 5:34 ` qiaozhou
2016-09-05 12:38 ` [PATCH] power: avoid calling cancel_delayed_work_sync() during early boot Tejun Heo
2016-09-05 12:58 ` Rafael J. Wysocki
2016-09-04 1:29 [Question] about patch: don't use [delayed_]work_pending() Andreas Mohr
2016-09-05 12:41 ` Tejun Heo
2016-09-05 14:14 ` Andreas Mohr
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=d2501c4c-8e7b-bea3-1b01-000b36b5dfe9@asrmicro.com \
--to=qiaozhou@asrmicro.com \
--cc=gangwu@asrmicro.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=tj@kernel.org \
--cc=wilburwang@asrmicro.com \
/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).