From: Ingo Molnar <mingo@elte.hu>
To: Valdis.Kletnieks@vt.edu
Cc: Andrew Morton <akpm@linux-foundation.org>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Steven Rostedt <rostedt@goodmis.org>,
linux-kernel@vger.kernel.org,
Frederic Weisbecker <fweisbec@gmail.com>
Subject: Re: [PATCH 5/5] ring-buffer: fix printk output
Date: Wed, 29 Apr 2009 22:15:55 +0200 [thread overview]
Message-ID: <20090429201555.GG17021@elte.hu> (raw)
In-Reply-To: <25555.1241021943@turing-police.cc.vt.edu>
* Valdis.Kletnieks@vt.edu <Valdis.Kletnieks@vt.edu> wrote:
> On Tue, 28 Apr 2009 23:20:00 PDT, Andrew Morton said:
> > printk_once() is racy on smp and preempt btw ;)
>
> Looks like at worst, it's prone to the usual printk racing, plus a
> possible misfire causing it to print twice before shutting up? Or
> is there something I'm missing here?
Yeah, that's the worst-case scenario.
Still worth improving if we can do it without bloating the code or
data.
[ If not, we can just assume the kernel is perfect and ignore all
the printk_once() and WARN_ONCE() / WARN_ON_ONCE() callsites as
obviously dead code ;-) ]
Ingo
next prev parent reply other threads:[~2009-04-29 20:16 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-29 4:48 [PATCH 0/5] [GIT PULL] tracing/splice/ringbuffer: updates for tip Steven Rostedt
2009-04-29 4:48 ` [PATCH 1/5] tracing: convert ftrace_dump spinlocks to raw Steven Rostedt
2009-04-29 5:07 ` Andrew Morton
2009-04-29 5:55 ` Ingo Molnar
2009-04-29 4:48 ` [PATCH 2/5] tracing: fix ref count in splice pages Steven Rostedt
2009-04-29 4:48 ` [PATCH 3/5] tracing: only add splice page if entries exist Steven Rostedt
2009-04-29 4:48 ` [PATCH 4/5] tracing: have splice only copy full pages Steven Rostedt
2009-04-29 4:48 ` [PATCH 5/5] ring-buffer: fix printk output Steven Rostedt
2009-04-29 5:20 ` Andrew Morton
2009-04-29 5:43 ` Ingo Molnar
2009-04-29 5:55 ` Andrew Morton
2009-04-29 6:09 ` Ingo Molnar
2009-04-29 6:20 ` Andrew Morton
2009-04-29 7:22 ` Ingo Molnar
2009-04-29 7:41 ` Andrew Morton
2009-04-29 9:56 ` Ingo Molnar
2009-04-29 15:09 ` Andrew Morton
2009-04-29 19:45 ` Ingo Molnar
2009-04-29 19:52 ` Andrew Morton
2009-04-29 20:11 ` Ingo Molnar
2009-04-29 16:19 ` Valdis.Kletnieks
2009-04-29 20:15 ` Ingo Molnar [this message]
2009-04-29 6:03 ` [PATCH 0/5] [GIT PULL] tracing/splice/ringbuffer: updates for tip Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090429201555.GG17021@elte.hu \
--to=mingo@elte.hu \
--cc=Valdis.Kletnieks@vt.edu \
--cc=akpm@linux-foundation.org \
--cc=fweisbec@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=sfr@canb.auug.org.au \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.