Re: [PATCH -v2 1/2] ratelimit: Extend to print suppressed messages on release

From: Ingo Molnar
Date: Fri Jul 01 2016 - 07:26:49 EST



* Borislav Petkov <bp@xxxxxxxxx> wrote:

> On Fri, Jul 01, 2016 at 10:22:47AM +0200, Ingo Molnar wrote:
> > > +/* issue num suppressed message on exit */
> > > +#define RATELIMIT_MSG_ON_RELEASE BIT(0)
> >
> > So this flag says that we should issue a ratelimit message when it occurs.
>
> This flag says that we should print the ratelimit message when we
> release the ratelimit state, i.e., devkmsg_release() for example.
>
> > But here we print the message if the RATELIMIT_MSG_ON_RELEASE bit is zero.
> > Is that intentional?
>
> Sure, we want to dump the ratelimited messages only when we release the
> ratelimit state.

ah, I see, I was being dim - never mind!

> > Also, while we are changing it, I'd like to suggest a different message - it's
> > talking about 'callbacks' but there's no callback here - we are skipping kernel
> > log messages. So how about:
> >
> > pr_warn("%s: %d kernel log lines skipped, due to rate-limiting.\n"
>
> Well, I'm not sure: even though the majority of the ratelimit usage is
> printing stuff and it has been carved out from printk.c, it still is a
> generic facility and you probably want to ratelimit other things too
> with it, like polling for something or whatnot.

Yeah, indeed, you are right.

Thanks,

Ingo