linux-kernel - Re: [PATCH 02/10] rcu: Move rcu_preempt_depth

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAJhGHyDjoQ3TrApksYJ5o1ooU4s8rzys2UnfF6EFzGwkaSVaKA@mail.gmail.com>
Date: Mon, 1 Apr 2024 00:16:42 +0800
From: Lai Jiangshan <jiangshanlai@...il.com>
To: Joel Fernandes <joel@...lfernandes.org>
Cc: linux-kernel@...r.kernel.org, rcu@...r.kernel.org, x86@...nel.org, 
	Lai Jiangshan <jiangshan.ljs@...group.com>, "Paul E. McKenney" <paulmck@...nel.org>, 
	Peter Zijlstra <peterz@...radead.org>, Frederic Weisbecker <frederic@...nel.org>, 
	Neeraj Upadhyay <quic_neeraju@...cinc.com>, Josh Triplett <josh@...htriplett.org>, 
	Boqun Feng <boqun.feng@...il.com>, Steven Rostedt <rostedt@...dmis.org>, 
	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>, Zqiang <qiang.zhang1211@...il.com>
Subject: Re: [PATCH 02/10] rcu: Move rcu_preempt_depth_set() to rcupdate.h

On Sun, Mar 31, 2024 at 7:10 PM Joel Fernandes <joel@...lfernandes.org> wrote:
>
>
>
> > On Mar 28, 2024, at 1:20 PM, Lai Jiangshan <jiangshanlai@...il.com> wrote:
> >
> > From: Lai Jiangshan <jiangshan.ljs@...group.com>
> >
> > Prepare for arch-specific-defined rcu_preempt_depth_set().
> >
> > No functionality change intended, but it has to be defined as a macro
> > as rcupdate.h is a very low level header included from areas that don't
> > even know about the task struct "current".
>
> Sorry I did not follow changelog. If some rcupdate.h includers do not know
> about task_struct, how does adding a macro that uses current help?
>

Hello

This is how macro works and it expands blindly based on tokens on the
usage-sites.

And rcu_preempt_depth() & rcu_preempt_depth_set() are not universally
used wrappers, the user can simply also include linux/sched.h to make
they work.

Thanks
Lai