linux-ext4 - Re: [PATCH, RFC 2/3] jbd2: Change j_state_lock to be a rwlock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100804000839.GI9453@thunk.org>
Date:	Tue, 3 Aug 2010 20:08:39 -0400
From:	Ted Ts'o <tytso@....edu>
To:	Ext4 Developers List <linux-ext4@...r.kernel.org>,
	ocfs2-devel@....oracle.com
Cc:	John Stultz <johnstul@...ibm.com>,
	Keith Maanthey <kmannth@...ibm.com>,
	Eric Whitney <eric.whitney@...com>
Subject: Re: [PATCH, RFC 2/3] jbd2: Change j_state_lock to be a rwlock_t

On Tue, Aug 03, 2010 at 12:01:54PM -0400, Theodore Ts'o wrote:
> Lockstat reports have shown that j_state_lock is a major source of
> lock contention, especially on systems with more than 4 CPU cores.  So
> change it to be a read/write spinlock.
> 
> Signed-off-by: "Theodore Ts'o" <tytso@....edu>

Oops, this patch can result in a BUG_ON in fs/jbd2/transaction.c.  I'm
currently testing a fix/replacement patch, but I figured I send a
quick warning to folks not to waste time trying this out just yet.  I
should hopefully have a new, better-tested patch in by tomorrow
morning.

						- Ted

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html