Re: linux.git: printk() problem

From	Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Newsgroups	linux.kernel
Subject	Re: linux.git: printk() problem
Date	2016-10-25 06:50 +0200
Message-ID	<sw1Qt-MZ-9@gated-at.bofh.it> (permalink)
References	(5 earlier) <svZbX-7gE-7@gated-at.bofh.it> <svZlD-7z6-5@gated-at.bofh.it> <svZEZ-7Nb-3@gated-at.bofh.it> <sw1dL-t9-1@gated-at.bofh.it> <sw1x7-Gn-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On (10/24/16 21:15), Linus Torvalds wrote:
[..]
> No. Most cont lines never hit the delay, because when the line is
> completed, it is flushed (and then printed synchronously, assuming it
> can get the console lock).
> 
> So the timeout only ever comes into effect if the line isn't completed
> in time at all. Which is actually very rare, and never happens for the
> "let's print things out in multiple chinks because we're using a
> loop".
> 
> Similarly, if a new printk() happens due to interleaving, the previous
> buffered line is always flushed first, so buffering never causes
> out-of-order behavior.

thanks. the patch works fine on my x86 box.

> Basically, the only time the timer actually does anything is if
> something just does a printk() without a newline, and no other
> printouts happen for the next 0.1s.

ok. perhaps, like slow serial console. will test on arm board later.

	-ss

Thread

Re: linux.git: printk() problem Geert Uytterhoeven <geert@linux-m68k.org> - 2016-10-23 11:30 +0200
  Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-23 20:20 +0200
    Re: linux.git: printk() problem Joe Perches <joe@perches.com> - 2016-10-23 21:10 +0200
      Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-23 21:40 +0200
        Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-23 21:50 +0200
          Re: linux.git: printk() problem Geert Uytterhoeven <geert@linux-m68k.org> - 2016-10-24 13:20 +0200
          Re: linux.git: printk() problem Sergey Senozhatsky <sergey.senozhatsky@gmail.com> - 2016-10-24 16:20 +0200
            Re: linux.git: printk() problem Sergey Senozhatsky <sergey.senozhatsky@gmail.com> - 2016-10-24 16:30 +0200
            Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-24 20:00 +0200
              Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-24 20:00 +0200
                Re: linux.git: printk() problem Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2016-10-25 04:00 +0200
                Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-25 04:10 +0200
                Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-25 04:30 +0200
                Re: linux.git: printk() problem Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2016-10-25 06:10 +0200
                Re: linux.git: printk() problem Joe Perches <joe@perches.com> - 2016-10-25 06:20 +0200
                Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-25 06:30 +0200
                Re: linux.git: printk() problem Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2016-10-25 06:50 +0200
                Re: linux.git: printk() problem Petr Mladek <pmladek@suse.com> - 2016-10-25 16:50 +0200
                Re: linux.git: printk() problem Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2016-10-25 04:30 +0200
        Re: linux.git: printk() problem Joe Perches <joe@perches.com> - 2016-10-23 22:40 +0200
          Re: linux.git: printk() problem Linus Torvalds <torvalds@linux-foundation.org> - 2016-10-23 23:20 +0200
    Re: linux.git: printk() problem Steven Rostedt <rostedt@goodmis.org> - 2016-10-25 16:50 +0200

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