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Date:   Mon, 27 Jun 2022 09:22:37 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Tejun Heo <tj@kernel.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Christian Brauner <brauner@kernel.org>,
        Petr Mladek <pmladek@suse.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Michal Hocko <mhocko@suse.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH 3/3] kthread: Stop abusing TASK_UNINTERRUPTIBLE
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Bit off a tangent..

On Mon, Jun 27, 2022 at 05:23:00AM +0900, Tejun Heo wrote:

> This is a bit of bike-shedding but there are inherent downsides to
> callback based interface in terms of write/readability. Now you have
> to move the init code out of line, and if the context that needs to be
> passing doesn't fit in a single pointer, you gotta define a struct to
> carry it adding to the boilerplate.

Yes, I so wish C had reasonable lambda expressions :/ But even if we
could come up with a semi sensible syntax and implementation, it would
still be many *many* years before we could actually use it in-kernel :-(