From: Greg KH <gregkh@linuxfoundation.org>
To: Zheng Yejian <zhengyejian1@huawei.com>
Cc: rostedt@goodmis.org, mhiramat@kernel.org,
linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
stable@vger.kernel.org
Subject: Re: [PATCH 5.10] tracing: Add tracing_reset_all_online_cpus_unlocked() function
Date: Mon, 19 Jun 2023 10:26:51 +0200 [thread overview]
Message-ID: <2023061913-dosage-repacking-678e@gregkh> (raw)
In-Reply-To: <20230615204931.3250659-1-zhengyejian1@huawei.com>
On Fri, Jun 16, 2023 at 04:49:31AM +0800, Zheng Yejian wrote:
> From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
>
> commit e18eb8783ec4949adebc7d7b0fdb65f65bfeefd9 upstream.
>
> Currently the tracing_reset_all_online_cpus() requires the
> trace_types_lock held. But only one caller of this function actually has
> that lock held before calling it, and the other just takes the lock so
> that it can call it. More users of this function is needed where the lock
> is not held.
>
> Add a tracing_reset_all_online_cpus_unlocked() function for the one use
> case that calls it without being held, and also add a lockdep_assert to
> make sure it is held when called.
>
> Then have tracing_reset_all_online_cpus() take the lock internally, such
> that callers do not need to worry about taking it.
>
> Link: https://lkml.kernel.org/r/20221123192741.658273220@goodmis.org
>
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Zheng Yejian <zhengyejian1@huawei.com>
> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> [this patch is pre-depended by be111ebd8868d4b7c041cb3c6102e1ae27d6dc1d
> due to tracing_reset_all_online_cpus() should be called after taking lock]
> Fixes: be111ebd8868 ("tracing: Free buffers when a used dynamic event is removed")
> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
> ---
What about for 5.15.y? You can't apply a fix to just an older tree as
you will then have a regression when you update.
I'll drop this one from my queue, please resend a backport for all
relevent stable releases.
thanks,
greg k-h
next prev parent reply other threads:[~2023-06-19 8:27 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-15 20:49 [PATCH 5.10] tracing: Add tracing_reset_all_online_cpus_unlocked() function Zheng Yejian
2023-06-19 8:26 ` Greg KH [this message]
2023-06-19 13:38 ` Zheng Yejian
-- strict thread matches above, loose matches on Subject: below --
2023-06-20 1:31 Zheng Yejian
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=2023061913-dosage-repacking-678e@gregkh \
--to=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=rostedt@goodmis.org \
--cc=stable@vger.kernel.org \
--cc=zhengyejian1@huawei.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).