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From:   Joel Fernandes <joel@joelfernandes.org>
Date:   Tue, 17 Jan 2023 19:45:12 +0000
Message-ID: <CAEXW_YRYuroym5e4ApJ8oYofsocVj6ApCmCCf07kfJy=PD-9ww@mail.gmail.com>
Subject: Re: [PATCH v2 rcu/dev 1/2] rcu: Track laziness during boot and suspend
To:     paulmck@kernel.org
Cc:     Steven Rostedt <rostedt@goodmis.org>, linux-kernel@vger.kernel.org,
        Josh Triplett <josh@joshtriplett.org>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        rcu@vger.kernel.org, fweisbec@gmail.com, urezki@gmail.com
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On Tue, Jan 17, 2023 at 7:37 PM Paul E. McKenney <paulmck@kernel.org> wrote:
>
> On Tue, Jan 17, 2023 at 02:32:24PM -0500, Steven Rostedt wrote:
> > On Sun, 15 Jan 2023 16:34:58 -0500
> > Joel Fernandes <joel@joelfernandes.org> wrote:
> >
> > > > > +EXPORT_SYMBOL_GPL(rcu_async_hurry);
> > > > >
> > > >
> > > > Where do you plan on calling these externally, as they are being
> > > > marked exported?
> > > >
> > > > If you allow random drivers to enable this, I can see something
> > > > enabling it and hitting an error path that causes it to never disable
> > > > it.
> > >
> > > You mean, just like rcu_expedite_gp() ?
> > >
> > > > I wouldn't have EXPORT_SYMBOL_GPL() unless you really know that it is
> > > > needed externally.
> > >
> > > At the moment it is not called externally but in the future, it could
> > > be from rcutorture. If you see rcu_expedite_gp(), that is exported
> > > too. I was just modeling it around that API.
> >
> > The reason for the export should have been mentioned in the change log if
> > the patch is not obvious to why it is being exported.
>
> Would something like this suffice?  With attribution, of course.
>
>         Export rcu_async_should_hurry(), rcu_async_hurry(), and
>         rcu_async_relax() for later use by rcutorture.

Looks good to me Paul, and thanks for the suggestion Steven!

 - Joel