lkml.org 
[lkml]   [2011]   [Nov]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: Printk mulitple line message support
    From
    Date
    On Tue, 2011-11-15 at 10:30 +0800, Joe Perches wrote:
    > On Tue, 2011-11-15 at 09:52 +0800, Huang Ying wrote:
    > > On Tue, 2011-11-15 at 09:18 +0800, Joe Perches wrote:
    > > > I believe you are not solving any real problem
    > > > with pr_<level>_ml.
    > > > Most all interleaved complete line uses have some
    > > > pr_fmt prefix that distinguishes between the sources.
    > > Except dev_<level> and netdev_<level>, it appears that many general
    > > pr_<level> do not have the prefix.
    >
    > I'm working on that.
    > There are a lot of them and it's a slog.

    Em... so you think we do not need a general solution? Just use various
    prefix for these pr_<level>?

    The down side of this solution is that it is hard to use a simple script
    to distinguish interleaved message easily.

    > > > A perhaps larger problem is interleaved partial
    > > > lines with pr_cont.
    > > In an interleaved situation, how to determine <level> for pr_cont?
    >
    > pr_cont has its own KERN_CONT level, it's "<c>", which
    > is stripped from output by printk. It's used to continue
    > the previous printks output on a single line.

    Sorry. Had some misunderstanding about pr_cont.

    > > > I believe that an initiator/terminator is necessary
    > > > for reassembly. Something that could be used
    > > > with pr_<level>, dev_<level>, netdev_<level>, et al.
    > > >
    > > > mp_start(&cookie)
    > > > pr_<level>(fmt, ...);
    > >
    > > Do not need cookie here?
    >
    > Ideally not.
    >
    > > > pr_mp_cont(&cookie, fmt, ...);
    > > > pr_mp_cont(&cookie, fmt "\n", ...);
    > > > mp_end(&cookie);
    > >
    > > With initiator/terminator the kernel log will be more structural, but
    > > that will make kernel log a little harder to read too.
    >
    > Initiator/terminator would not be part of printk output
    > but could exist simply to set/track the atomic/cookie #
    > and have printk output the appropriate cookie id when
    > more than 1 cookie is active.

    Oh. I see.

    For multiple part in one line. I think the better solution may be to
    assemble them in a line buffer before real output to console to avoid
    interleaving. Do you think so?

    Best Regards,
    Huang Ying




    \
     
     \ /
      Last update: 2011-11-15 04:01    [W:0.034 / U:29.620 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site