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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Petr Pavlu <petr.pavlu@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	"Masami Hiramatsu (Google)" <mhiramat@kernel.org>,
	linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	Mark Rutland <mark.rutland@arm.com>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Luis Chamberlain <mcgrof@kernel.org>,
	Sami Tolvanen <samitolvanen@google.com>,
	Daniel Gomez <da.gomez@samsung.com>, linux-modules@vger.kernel.org
Subject: Re: [PATCH 5/8] module: Add module_for_each_mod() function
Message-ID: <20250210140803.yAy54W0Q@linutronix.de>
References: <20250205225031.799739376@goodmis.org>
 <20250205225103.760856859@goodmis.org>
 <20250206142817.91853f475c681bc2ef7ca962@kernel.org>
 <20250206102720.0fd57129@gandalf.local.home>
 <bfe05b54-9714-46bc-9b59-ad091897c62d@suse.com>
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In-Reply-To: <bfe05b54-9714-46bc-9b59-ad091897c62d@suse.com>

On 2025-02-10 14:04:35 [+0100], Petr Pavlu wrote:
> >> BTW, do we really need to disable preempt or is it enough to call
> >> rcu_read_lock()?
> > 
> > Bah, as I expected this function to be changed, I didn't spend too much
> > time on looking at its implementation. I just cut and pasted how the other
> > loops worked. But yes, it should not be disabling preemption. In fact, I
> > think the module code itself should not be disabling preemption!
> > 
> > I'll have to go and look into that.
> 
> The series "module: Use RCU instead of RCU-sched" from Sebastian Andrzej
> Siewior cleans this up [1]. It is currently queued on modules-next (for
> 6.15-rc1).
> 
> The new function module_for_each_mod() should then use "guard(rcu)();".

So the removal of the preempt-disable statements here already pays off.
Nice.

Sebastian