From: Bill Davidsen <davidsen@tmr.com>
To: Ulrich Drepper <drepper@gmail.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
jakub@redhat.com
Subject: Re: [PATCH] 2.6.16 - futex: small optimization (?)
Date: Tue, 28 Mar 2006 17:46:04 -0500 [thread overview]
Message-ID: <4429BCAC.80208@tmr.com> (raw)
In-Reply-To: <a36005b50603280702n2979d8ddh97484615ea9d4f3a@mail.gmail.com>
Ulrich Drepper wrote:
> On 3/27/06, Pierre PEIFFER <pierre.peiffer@bull.net> wrote:
>> I found a (optimization ?) problem in the futexes, during a futex_wake,
>> if the waiter has a higher priority than the waker.
>
> There are no such situations anymore in an optimal userlevel
> implementation. The last problem (in pthread_cond_signal) was fixed
> by the addition of FUTEX_WAKE_OP. The userlevel code you're looking
> at is simply not optimized for the modern kernels.
What are you suggesting here, that the kernel can be inefficient as long
as the user has a way to program around it?
--
-bill davidsen (davidsen@tmr.com)
"The secret to procrastination is to put things off until the
last possible moment - but no longer" -me
next prev parent reply other threads:[~2006-03-28 23:09 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-03-28 7:37 [PATCH] 2.6.16 - futex: small optimization (?) Pierre PEIFFER
2006-03-28 10:05 ` Eric Dumazet
2006-03-28 15:02 ` Ulrich Drepper
2006-03-28 22:46 ` Bill Davidsen [this message]
2006-03-29 15:26 ` Ingo Molnar
2006-03-30 20:27 ` Bill Davidsen
2006-03-31 6:01 ` Ingo Molnar
2006-03-31 14:50 ` Bill Davidsen
2006-03-31 18:15 ` Ingo Molnar
2006-03-29 13:18 ` Pierre PEIFFER
2006-03-29 15:26 ` Eric Dumazet
2006-03-30 14:51 ` Pierre PEIFFER
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