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Date: Wed, 13 Nov 2019 10:23:37 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Petr Mladek <pmladek@suse.com>, Dmitry Safonov <dima@arista.com>
Subject: Re: [PATCH 00/50] Add log level to show_stack()
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Cc: Juri Lelli <juri.lelli@redhat.com>,
 Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
 linux-sh@vger.kernel.org, Catalin Marinas <catalin.marinas@arm.com>,
 Ben Segall <bsegall@google.com>, Guo Ren <guoren@kernel.org>,
 Pavel Machek <pavel@ucw.cz>, Vincent Guittot <vincent.guittot@linaro.org>,
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On (19/11/12 19:12), Sergey Senozhatsky wrote:
> On (19/11/12 09:35), Petr Mladek wrote:
> [..]
> > This is getting too complicated. It would introduce too many
> > hidden rules. While the explicitly passed loglevel parameter
> > is straightforward and clear.
>
> If loglevel is DEFAULT or NOTICE or INFO then we can overwrite it
> (either downgrade or upgrade). That's one rule, basically. Not too
> complicated, I guess.

Can be taken even a bit further than

	show_stack(NULL, NULL, LOGLEVEL_DEBUG);
or
	show_stack(NULL, NULL, LOGLEVEL_ERR);

For instance,

	spin_lock_irqsave(&rq->lock, flags);
	printk_emergency_enter(LOGLEVEL_SCHED);
		...
		show_stack(...);
		printk();
		printk();
		...
	spin_unlock_irqrestore(&rq->lock, flags);

or

	spin_lock_irqsave(&uart_port->lock, flags);
	printk_emergency_enter(LOGLEVEL_SCHED);
		...
		printk();
		printk();
		...

and so on.

	-ss