From: "Eugeny S. Mints" <emints@ru.mvista.com>
To: Vadim Lebedev <vadim@mbdsys.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [ANNOUNCE] Linux 2.6 Real Time Kernel
Date: Mon, 11 Oct 2004 19:50:30 +0400 [thread overview]
Message-ID: <416AABC6.8040405@ru.mvista.com> (raw)
In-Reply-To: <200410111728.39200.vadim@mbdsys.com>
Vadim Lebedev wrote:
> Sven-Thorsten Dietrich <sdietrich@mvista.com> wrote in message
> news:<2Nir3-4iC-13@gated-at.bofh.it>...
>
>>Announcing the availability of prototype real-time (RT)
>>enhancements to the Linux 2.6 kernel.
>
>
> Reading the sources i believe that __p_mutex_up is not constant time
> operation because of __p_mutex_down....
>
> It is clear that
> __p_mutex_down is not constant time operation because of insertion
> into the priority-sorted sleepers list. However both __p_mutex_down
> and __p_mutex_up are synchronize on the same global spinlock
> (m_spin_lock) .... so if the __p_mutex_down is holding this spinlock
> while inserting NO other process(or) is able to perform any __p_mutex
> operation...
Current pmutex implementation was chosen only as prototype
implementation. kmutex abstraction layer allows to switch easily between
any (alternative) mutex implementations and to choose optimal one on a
benchmarking basis.
>
> Maybe the better idea would be to have a per-mutex spinlock? or even
> better, given that the task->rt_priority have a finite range maybe each
> mutex can have a table of sleeper lists indexed by rt_priority?
>
>
> Vadim
> -
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>
>
next prev parent reply other threads:[~2004-10-11 16:02 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-10-11 15:28 [ANNOUNCE] Linux 2.6 Real Time Kernel Vadim Lebedev
2004-10-11 15:50 ` Eugeny S. Mints [this message]
-- strict thread matches above, loose matches on Subject: below --
2004-10-09 22:54 Sven Dietrich
2004-10-09 11:38 John Hedditch
2004-10-09 5:59 Sven-Thorsten Dietrich
2004-10-09 6:40 ` Lee Revell
2004-10-09 7:33 ` Daniel Walker
2004-10-09 7:42 ` Lee Revell
2004-10-09 23:40 ` Matthias Urlichs
2004-10-09 8:52 ` Lee Revell
2004-10-09 23:20 ` Dave Hansen
2004-10-09 23:24 ` Lee Revell
2004-10-09 10:51 ` Måns Rullgård
2004-10-09 13:15 ` Måns Rullgård
2004-10-09 21:20 ` Lee Revell
2004-10-09 21:35 ` Måns Rullgård
2004-10-09 21:37 ` Lee Revell
2004-10-09 21:45 ` Måns Rullgård
2004-10-09 21:55 ` Lee Revell
2004-10-09 22:21 ` Måns Rullgård
2004-10-09 23:52 ` Lee Revell
2004-10-10 0:05 ` Måns Rullgård
2004-10-10 0:45 ` Lee Revell
2004-10-10 1:05 ` Måns Rullgård
2004-10-10 1:09 ` Lee Revell
2004-10-10 0:43 ` Micha Feigin
2004-10-10 1:08 ` Måns Rullgård
2004-10-09 17:41 ` Karim Yaghmour
2004-10-09 18:30 ` Lee Revell
2004-10-09 21:26 ` stefan.eletzhofer
2004-10-09 19:30 ` Lee Revell
2004-10-09 19:38 ` Måns Rullgård
2004-10-09 21:38 ` stefan.eletzhofer
2004-10-09 19:47 ` Lee Revell
2004-10-09 20:11 ` Karim Yaghmour
2004-10-09 20:14 ` Lee Revell
2004-10-09 20:53 ` Karim Yaghmour
2004-10-09 20:59 ` Lee Revell
2004-10-09 20:20 ` Robert Love
2004-10-09 20:25 ` Lee Revell
2004-10-10 1:15 ` Lee Revell
2004-10-10 8:46 ` Ingo Molnar
2004-10-10 19:41 ` Daniel Walker
2004-10-10 19:46 ` Ingo Molnar
2004-10-10 21:20 ` Andrew Morton
2004-10-10 21:59 ` Ingo Molnar
2004-10-11 17:53 ` Daniel Walker
2004-10-11 20:49 ` Ingo Molnar
2004-10-11 21:44 ` Sven Dietrich
2004-10-11 21:54 ` Ingo Molnar
2004-10-11 23:05 ` Sven Dietrich
2004-10-12 5:50 ` Ingo Molnar
2004-10-14 5:09 ` Dipankar Sarma
2004-10-14 7:18 ` Ingo Molnar
2004-10-15 14:59 ` Paul E. McKenney
2004-10-15 15:45 ` Ingo Molnar
2004-10-15 16:40 ` Paul E. McKenney
2004-10-15 16:45 ` Paul E. McKenney
2004-10-17 17:12 ` Ingo Molnar
2004-10-12 18:50 ` Daniel Walker
2004-10-10 12:21 ` John Richard Moser
2004-10-10 17:26 ` Lee Revell
2004-10-10 18:45 ` John Richard Moser
2004-10-10 20:20 ` Ingo Molnar
2004-10-10 20:44 ` John Richard Moser
2004-10-10 17:29 ` Daniel Walker
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