Re: printk loglevel policy?

[Randy.Dunlap]

Keith Owens wrote:
> On Sun, 02 Jan 2005 13:41:34 -0800, 
> "Randy.Dunlap" <rddunlap@xxxxxxxx> wrote:
>
> > Jim Nelson wrote:
> >
> > > Or does printk() do some tracking that I didn't see as to where in the 
> > > kernel the strings are coming from?
> >
> > That kind of garbled output has been known to happen, but
> > the <console_sem> is supposed to prevent that (along with
> > zap_locks() in kernel/printk.c).
>
>
> Using multiple calls to printk to print a single line has always been
> subject to the possibility of interleaving on SMP.  We just live with
> the risk.  Printing a complete line in a single call to printk is
> protected by various locks.  Print a line in multiple calls is not
> protected.  If it bothers you that much, build up the line in a local
> buffer then call printk once.

True, I was thinking about the single line case, which I
have seen garbled/mixed in the past (on SMP).  Hopefully
that one is fixed.

--
~Randy
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