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Date: Fri, 30 Aug 2013 13:43:11 -0700
Message-ID: <CA+55aFzhiLMdSCnePX0OgFUXo7KC+aomM8URppDuV+7xUaaSpw@mail.gmail.com>
Subject: Re: [PATCH v7 1/4] spinlock: A new lockref structure for lockless
 update of refcount
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Waiman Long <waiman.long@hp.com>
Cc: Ingo Molnar <mingo@kernel.org>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Jeff Layton <jlayton@redhat.com>, Miklos Szeredi <mszeredi@suse.cz>,
        Ingo Molnar <mingo@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>, Andi Kleen <andi@firstfloor.org>,
        "Chandramouleeswaran, Aswin" <aswin@hp.com>,
        "Norton, Scott J" <scott.norton@hp.com>
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On Fri, Aug 30, 2013 at 1:15 PM, Waiman Long <waiman.long@hp.com> wrote:
>
> The prepend_path() isn't all due to getcwd. The correct profile should be

Ugh. I really think that prepend_path() should just be rewritten to
run entirely under RCU.

Then we can remove *all* the stupid locking, and replace it with doing
a read-lock on the rename sequence count, and repeating if requited.

That shouldn't even be hard to do, it just requires mindless massaging
and being careful.

             Linus
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