From: Viresh Kumar <viresh.kumar@linaro.org>
To: Dmitry Osipenko <digetx@gmail.com>
Cc: Viresh Kumar <vireshk@kernel.org>,
Stephen Boyd <sboyd@kernel.org>, Nishanth Menon <nm@ti.com>,
linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH v1] opp: Release current OPP properly
Date: Fri, 13 Aug 2021 09:42:24 +0530 [thread overview]
Message-ID: <20210813041224.dqz3kbynr5ffjclj@vireshk-i7> (raw)
In-Reply-To: <20210812101353.14318-1-digetx@gmail.com>
On 12-08-21, 13:13, Dmitry Osipenko wrote:
> The current_opp is released only when whole OPP table is released,
> otherwise it's only marked as removed by dev_pm_opp_remove_table().
> Functions like dev_pm_opp_put_clkname() and dev_pm_opp_put_supported_hw()
> are checking whether OPP table is empty and it's not if current_opp is
> set since it holds the refcount of OPP, this produces a noisy warning
> from these functions about busy OPP table. Release current_opp when
> OPP table is removed to fix it.
>
> Cc: stable@vger.kernel.org
> Fixes: 81c4d8a3c414 ("opp: Keep track of currently programmed OPP")
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
> drivers/opp/core.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
> index b335c077f215..73da968b5c86 100644
> --- a/drivers/opp/core.c
> +++ b/drivers/opp/core.c
> @@ -1378,9 +1378,6 @@ static void _opp_table_kref_release(struct kref *kref)
> list_del(&opp_table->node);
> mutex_unlock(&opp_table_lock);
>
> - if (opp_table->current_opp)
> - dev_pm_opp_put(opp_table->current_opp);
> -
> _of_clear_opp_table(opp_table);
>
> /* Release clk */
> @@ -2901,6 +2898,12 @@ void dev_pm_opp_remove_table(struct device *dev)
> if (_opp_remove_all_static(opp_table))
> dev_pm_opp_put_opp_table(opp_table);
>
> + /* Drop reference taken by _find_current_opp() */
> + if (opp_table->current_opp) {
> + dev_pm_opp_put(opp_table->current_opp);
> + opp_table->current_opp = NULL;
> + }
> +
It is better to drop the reference when the OPP table is really
getting removed.
I think the WARN_ON() in the put_* functions can be dropped. It is
important to check this when the stuff is getting set, like in
dev_pm_opp_set_supported_hw(), but removal is just fine.
--
viresh
next prev parent reply other threads:[~2021-08-13 4:12 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-12 10:13 [PATCH v1] opp: Release current OPP properly Dmitry Osipenko
2021-08-13 4:12 ` Viresh Kumar [this message]
2021-08-13 17:23 ` Dmitry Osipenko
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=20210813041224.dqz3kbynr5ffjclj@vireshk-i7 \
--to=viresh.kumar@linaro.org \
--cc=digetx@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=nm@ti.com \
--cc=sboyd@kernel.org \
--cc=vireshk@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).