Re: [RFC][PATCH v6 0/2] printk: Make printk() completely async

From	Pavel Machek <pavel@ucw.cz>
Newsgroups	linux.kernel
Subject	Re: [RFC][PATCH v6 0/2] printk: Make printk() completely async
Date	2016-04-23 21:50 +0200
Message-ID	<rrbIZ-a3-3@gated-at.bofh.it> (permalink)
References	<rfbOq-qS-11@gated-at.bofh.it> <rfoiB-C0-7@gated-at.bofh.it>
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On Tue 2016-03-22 07:49:48, Jan Kara wrote:
> Hi,
> 
> On Tue 22-03-16 02:25:28, Sergey Senozhatsky wrote:
> >  The patch set is based on slightly updated Jan Kara's patches.
> > 
> > This patch set makes printk() completely asynchronous: new messages
> > are getting upended to the kernel printk buffer, but instead of 'direct'
> > printing the actual print job is performed by a dedicated kthread.
> > This has the advantage that printing always happens from a schedulable
> > context and thus we don't lockup any particular CPU or even interrupts.
> > 
> > The patch set is against next-20160321
> > 
> > the series in total has 3 patches:
> > - printk: Make printk() completely async
> > - printk: Make wake_up_klogd_work_func() async
> > - printk: make console_unlock() async
> > 
> > per discussion, "printk: make console_unlock() async" will be posted
> > later on.
> 
> Patches look good to me. I don't think you need to mention the
> console_unlock() async patch when it is not part of the series.  BTW, you
> seemed to have dropped my patch to skip if there are too many buffered
> messages when oops is in progress. Any reason for that?

So... from basically linux 0.0, cli() printk("") could be used for
debugging. ... and that's now gone. Right?

Can you explain why that is good idea?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [RFC][PATCH v6 0/2] printk: Make printk() completely async Pavel Machek <pavel@ucw.cz> - 2016-04-23 21:50 +0200
  Re: [RFC][PATCH v6 0/2] printk: Make printk() completely async Sergey Senozhatsky <sergey.senozhatsky@gmail.com> - 2016-04-24 06:20 +0200
    Re: [RFC][PATCH v6 0/2] printk: Make printk() completely async Pavel Machek <pavel@ucw.cz> - 2016-04-24 15:40 +0200
      Re: [RFC][PATCH v6 0/2] printk: Make printk() completely async Sergey Senozhatsky <sergey.senozhatsky@gmail.com> - 2016-04-24 16:10 +0200

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