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Message-ID: <e1e3164eabf69e04ad9e9ddc259ca685f48c5e27.camel@perches.com>
Subject: Re: [RFC PATCH 1/5] printk: implement pr_cont_t
From:   Joe Perches <joe@perches.com>
To:     John Ogness <john.ogness@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        linux-kernel@vger.kernel.org
Date:   Wed, 19 Aug 2020 17:33:51 -0700
In-Reply-To: <20200819232632.13418-2-john.ogness@linutronix.de>
References: <20200819232632.13418-1-john.ogness@linutronix.de>
         <20200819232632.13418-2-john.ogness@linutronix.de>
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On Thu, 2020-08-20 at 01:32 +0206, John Ogness wrote:
> Implement a new buffering mechanism for pr_cont messages.
> 
> Old mechanism syntax:
> 
>     printk(KERN_INFO "text");
>     printk(KERN_CONT " continued");
>     printk(KERN_CONT "\n");
> 
> New mechanism syntax:
> 
>     pr_cont_t c;
> 
>     pr_cont_begin(&c, KERN_INFO "text");

bikeshed:

I suggest:

	printk_begin(&printk_context, fmt, ...)
	printk_continue(&printk_context, fmt, ...) (maybe printk_next())
	printk_end(&printk_context, fmt, ...)

and macros using pr_<level>_begin

ie:

#define pr_info_begin(context, fmt, ...)		\
	printk_begin(context, KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)

and each continued bit would use printk_continue or printk_end
as appropriate.

KERN_<LEVEL> could be a separate argument, but it's simple
enough to use
printk_get_level on the format.