From: Bjorn Helgaas <bjorn.helgaas@hp.com>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@osdl.org>
Subject: [PATCH] active_load_balance() deadlock
Date: Tue, 1 Jun 2004 14:09:54 -0600 [thread overview]
Message-ID: <200406011409.54478.bjorn.helgaas@hp.com> (raw)
active_load_balance() looks susceptible to deadlock when busiest==rq.
Without the following patch, my 128-way box deadlocks consistently
during boot-time driver init.
===== kernel/sched.c 1.304 vs edited =====
--- 1.304/kernel/sched.c 2004-05-27 02:26:55 -06:00
+++ edited/kernel/sched.c 2004-05-31 12:03:32 -06:00
@@ -1847,6 +1847,8 @@
}
rq = cpu_rq(push_cpu);
+ if (busiest == rq)
+ goto next_group;
double_lock_balance(busiest, rq);
move_tasks(rq, push_cpu, busiest, 1, sd, IDLE);
spin_unlock(&rq->lock);
next reply other threads:[~2004-06-01 20:09 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-06-01 20:09 Bjorn Helgaas [this message]
2004-06-01 20:19 ` Linus Torvalds
2004-06-01 20:46 ` 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=200406011409.54478.bjorn.helgaas@hp.com \
--to=bjorn.helgaas@hp.com \
--cc=akpm@osdl.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®