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Subject: Re: [RFC PATCH 1/5] printk: implement pr_cont_t
From:   Joe Perches <joe@perches.com>
To:     David Laight <David.Laight@ACULAB.COM>,
        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" <linux-kernel@vger.kernel.org>
Date:   Thu, 20 Aug 2020 00:59:30 -0700
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On Thu, 2020-08-20 at 07:44 +0000, David Laight wrote:
> I've no idea how you'd 'size' the number of buffers.

I believe they are static and assume no more than 10
simultaneous uses of
printk_begin

+#define CONT_LINE_MAX LOG_LINE_MAX
+#define CONT_BUF_COUNT 10
+static char cont_buf[CONT_BUF_COUNT][CONT_LINE_MAX];
+static DECLARE_BITMAP(cont_buf_map, CONT_BUF_COUNT);

Though I don't see much value in a separate define
for CONT_LINE_MAx