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Date:   Fri, 28 Sep 2018 18:02:04 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Alexander Potapenko <glider@google.com>,
        Dmitriy Vyukov <dvyukov@google.com>,
        kbuild test robot <fengguang.wu@intel.com>,
        syzkaller <syzkaller@googlegroups.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] printk: inject caller information into the body of
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On (09/28/18 01:10), Tetsuo Handa wrote:
> 
> Therefore, I think that "Either we need to require synchronization - umm... and
> document it - or to provide some means of synchronization in pr_line()." is a
> pointless worry. It is only existing printk() API which needs synchronization. I
> think that line buffered printk() API does not need to talk about synchronization.
> Just saying "don't share DEFINE_PR_LINE()/DEFINE_PR_LINE_BUF() variables" will be
> sufficient.

Agreed. My conclusion at the end was that - "pr_line is going to do as much
as seq_buf does". So pr_line won't provide any additional synchronization
mechanisms.

	-ss