From: Nick Piggin <nickpiggin@yahoo.com.au>
To: Tejun Heo <htejun@gmail.com>
Cc: ntl@pobox.com, viro@ftp.linux.org.uk, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC] big reader semaphore take#2
Date: Fri, 28 Oct 2005 21:06:56 +1000 [thread overview]
Message-ID: <43620650.4090903@yahoo.com.au> (raw)
In-Reply-To: <20051028104437.GA17461@htj.dyndns.org>
Tejun Heo wrote:
> Hello guys,
>
> This is the second take of brsem (big reader semaphore).
>
> Nick, unfortunately, simple array of rwsem's does not work as lock
> holders are not pinned down to cpus and may release locks on other
> cpus.
>
That's right. It would require down_read to return the index
or a pointer to the lock that it took, and to pass that into
up_read. So it wouldn't be a completely drop-in replacement
for a regular semaphore if that's what you had in mind?
Nick
--
SUSE Labs, Novell Inc.
Send instant messages to your online friends http://au.messenger.yahoo.com
next prev parent reply other threads:[~2005-10-28 11:07 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-10-28 10:44 [PATCH RFC] big reader semaphore take#2 Tejun Heo
2005-10-28 11:06 ` Nick Piggin [this message]
2005-11-04 15:09 ` Tejun Heo
2005-11-05 0:14 ` Nick Piggin
2005-11-05 1:18 ` Tejun Heo
2005-11-05 1:29 ` Nick Piggin
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