From: Arjan van de Ven <arjanv@redhat.com>
To: Hubertus Franke <frankeh@watson.ibm.com>
Cc: arjanv@redhat.com, Rusty Russell <rusty@rustcorp.com.au>,
linux-kernel@vger.kernel.org
Subject: Re: furwocks: Fast Userspace Read/Write Locks
Date: Thu, 7 Mar 2002 10:42:41 -0500 [thread overview]
Message-ID: <20020307104241.D24040@devserv.devel.redhat.com> (raw)
In-Reply-To: <E16iwkE-000216-00@wagner.rustcorp.com.au> <3C8761FF.A10E50D9@redhat.com> <20020307153228.3A6773FE06@smtp.linux.ibm.com>
In-Reply-To: <20020307153228.3A6773FE06@smtp.linux.ibm.com>; from frankeh@watson.ibm.com on Thu, Mar 07, 2002 at 10:33:32AM -0500
On Thu, Mar 07, 2002 at 10:33:32AM -0500, Hubertus Franke wrote:
> On Thursday 07 March 2002 07:50 am, Arjan van de Ven wrote:
> > Rusty Russell wrote:
> > > This is a userspace implementation of rwlocks on top of futexes.
> >
> > question: if rwlocks aren't actually slower in the fast path than
> > futexes,
> > would it make sense to only do the rw variant and in some userspace
> > layer
> > map "traditional" semaphores to write locks ?
> > Saves half the implementation and testing....
> > -
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.tux.org/lkml/
>
> I m not in favor of that. The dominant lock will be mutexes.
if there's no extra cost I don't care which is dominant; having one well
tested path is worth it then. If there is extra cost then yes a split is
better.
next prev parent reply other threads:[~2002-03-07 15:43 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-03-07 12:11 furwocks: Fast Userspace Read/Write Locks Rusty Russell
2002-03-07 12:40 ` Peter Wächtler
2002-03-07 14:41 ` Hubertus Franke
2002-03-07 12:50 ` Arjan van de Ven
2002-03-07 15:33 ` Hubertus Franke
2002-03-07 15:42 ` Arjan van de Ven [this message]
2002-03-07 19:11 ` Hubertus Franke
2002-03-07 20:17 ` H. Peter Anvin
2002-03-08 6:27 ` Rusty Russell
2002-03-08 6:29 ` H. Peter Anvin
2002-03-08 7:09 ` Rusty Russell
2002-03-08 19:32 ` Jamie Lokier
2002-03-08 1:22 ` Rusty Russell
2002-03-08 3:26 ` H. Peter Anvin
2002-03-08 9:21 ` Peter Wächtler
2002-03-08 18:13 ` Hubertus Franke
2002-03-09 4:50 ` Rusty Russell
2002-03-11 18:47 ` Hubertus Franke
2002-03-07 15:28 ` Hubertus Franke
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