From: Nam Cao <namcao@linutronix.de>
To: Gabriele Monaco <gmonaco@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
Masami Hiramatsu <mhiramat@kernel.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/6] rv: Remove rv_reactor's reference counter
Date: Mon, 21 Jul 2025 16:04:25 +0200 [thread overview]
Message-ID: <20250721140425.OeD16I4D@linutronix.de> (raw)
In-Reply-To: <2de814842fbbeee888e076db2f80bf2028fdbb0d.camel@redhat.com>
On Mon, Jul 21, 2025 at 03:20:44PM +0200, Gabriele Monaco wrote:
> Mmh, I'm not understanding how, let's assume I create a custom reactor
> as a kernel module and I want to use it on existing models (built in or
> modules themselves), I'd do.
>
> insmod myreactor
> echo myreactor > mymodel/reactors
> rmmod myreactor
> ## I want this one to fail because the reactor is in use
>
> echo nop > mymodel/reactors
> rmmod myreactor
> # now it can succeed
>
> How is MODULE_SOFTDEP helping in this scenario?
> Am I missing something here?
You are right, MODULE_SOFTDEP does not help this use case.
I did a quick search, it seems try_module_get() and module_put() are what
we need for this. Let me amend the commit message.
But my essential point in this patch is that, the current ref count
implementation does not work. Furthermore, we should use the centralized
kernel module's facilities, not implementing our own custom logic.
Best regards,
Nam
next prev parent reply other threads:[~2025-07-21 14:04 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-21 9:47 [PATCH 0/6] rv: Clean up & simplify Nam Cao
2025-07-21 9:47 ` [PATCH 1/6] rv: Remove unused field in struct rv_monitor_def Nam Cao
2025-07-21 13:01 ` Gabriele Monaco
2025-07-21 9:47 ` [PATCH 2/6] rv: Merge struct rv_monitor_def into struct rv_monitor Nam Cao
2025-07-21 14:13 ` Gabriele Monaco
2025-07-21 9:47 ` [PATCH 3/6] rv: Merge struct rv_reactor_def into struct rv_reactor Nam Cao
2025-07-21 14:29 ` Gabriele Monaco
2025-07-21 9:47 ` [PATCH 4/6] rv: Remove rv_reactor's reference counter Nam Cao
2025-07-21 13:20 ` Gabriele Monaco
2025-07-21 14:04 ` Nam Cao [this message]
2025-07-21 15:49 ` Gabriele Monaco
2025-07-22 8:27 ` Nam Cao
2025-07-22 8:30 ` Gabriele Monaco
2025-07-21 9:47 ` [PATCH 5/6] rv: Remove the nop reactor Nam Cao
2025-07-21 10:29 ` Gabriele Monaco
2025-07-21 14:10 ` Nam Cao
2025-07-21 9:47 ` [PATCH 6/6] rv: Remove struct rv_monitor::reacting Nam Cao
2025-07-21 14:38 ` Gabriele Monaco
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