LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Andrew Morton <akpm@osdl.org>
To: Ricky Beam <jfbeam@bluetronic.net>
Cc: linux-kernel@vger.kernel.org
Subject: Re: overlaping printk
Date: Thu, 20 May 2004 00:21:31 -0700 [thread overview]
Message-ID: <20040520002131.0afeceb9.akpm@osdl.org> (raw)
In-Reply-To: <Pine.GSO.4.33.0405191110380.14297-100000@sweetums.bluetronic.net>
Ricky Beam <jfbeam@bluetronic.net> wrote:
>
> Can anyone explain why the kernel does this on a serial console:
>
> C<PU0 >C2P:U M 3a:ch Mianech iCnhee cCk heExckc epEtxcieopnt: i0o0n0: 0000000000
> 0000000000000040
<looks>
<after three years, penny finally drops>
We bust the spinlock for *every* printk call. No wonder.
diff -puN kernel/printk.c~printk-mangling-fix kernel/printk.c
--- 25/kernel/printk.c~printk-mangling-fix 2004-05-20 00:20:06.388725128 -0700
+++ 25-akpm/kernel/printk.c 2004-05-20 00:20:27.228556992 -0700
@@ -492,8 +492,10 @@ asmlinkage int printk(const char *fmt, .
char *p;
static char printk_buf[1024];
static int log_level_unknown = 1;
+ static int once;
- if (oops_in_progress) {
+ if (oops_in_progress && !once) {
+ once = 1;
/* If a crash is occurring, make sure we can't deadlock */
spin_lock_init(&logbuf_lock);
/* And make sure that we print immediately */
_
next prev parent reply other threads:[~2004-05-21 23:47 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-05-19 15:19 Ricky Beam
2004-05-19 15:26 ` Tigran Aivazian
2004-05-19 15:31 ` Ricky Beam
2004-05-19 15:39 ` Randy.Dunlap
2004-05-20 7:21 ` Andrew Morton [this message]
2004-05-19 15:55 Tuukka Toivonen
2004-05-19 16:03 ` Ricky Beam
2004-05-20 14:03 ` Ingo Molnar
[not found] <1XBEP-Mc-49@gated-at.bofh.it>
[not found] ` <1XBXw-13D-3@gated-at.bofh.it>
[not found] ` <1XWpp-zy-9@gated-at.bofh.it>
2004-05-20 14:53 ` Andi Kleen
2004-05-20 15:19 ` Ingo Molnar
2004-05-20 15:53 ` Ingo Molnar
2004-05-20 16:19 ` Andy Isaacson
2004-05-20 18:57 ` Ingo Molnar
2004-05-20 23:11 ` Andrew Morton
2004-05-21 7:00 ` 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=20040520002131.0afeceb9.akpm@osdl.org \
--to=akpm@osdl.org \
--cc=jfbeam@bluetronic.net \
--cc=linux-kernel@vger.kernel.org \
--subject='Re: overlaping printk' \
/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
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).