Re: [PATCH 24/36] printk: Remove trace_.*_rcuidle() usage

From: Sergey Senozhatsky <senozhatsky@chromium.org>
To: Petr Mladek <pmladek@suse.com>
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Subject: Re: [PATCH 24/36] printk: Remove trace_.*_rcuidle() usage
Date: Sat, 11 Jun 2022 11:33:05 +0900	[thread overview]
Message-ID: <CA+_sPaq1ez7jah0bibAdeA__Yp92K_VA7E-NZ9knoUmOW9itJg@mail.gmail.com> (raw)
In-Reply-To: <YqHvXFdIJfvUDI6e@alley>

On Thu, Jun 9, 2022 at 10:02 PM Petr Mladek <pmladek@suse.com> wrote:
>
> On Thu 2022-06-09 20:30:58, Sergey Senozhatsky wrote:
> > My emails are getting rejected... Let me try web-interface
>
> Bad day for mail sending. I have problems as well ;-)

For me the problem is still there and apparently it's an "too many
recipients" error.

> > I'm somewhat curious whether we can actually remove that trace event.
>
> Good question.
>
> Well, I think that it might be useful. It allows to see trace and
> printk messages together.

Fair enough. Seems that back in 2011 people were pretty happy with it
https://lore.kernel.org/all/1322161388.5366.54.camel@jlt3.sipsolutions.net/T/#m7bf6416f469119372191f22a6ecf653c5f7331d2

but... reportedly, one of the folks who Ack-ed it (*cough cough*
PeterZ) has never used it.

> It was ugly when it was in the console code. The new location
> in vprintk_store() allows to have it even "correctly" sorted
> (timestamp) against other tracing messages.

That's true.