From mboxrd@z Thu Jan  1 00:00:00 1970
References: <20150919112648.GB22852@hermes.click-hack.org>
From: Jan Kiszka <jan.kiszka@siemens.com>
Message-ID: <5601A396.7020605@siemens.com>
Date: Tue, 22 Sep 2015 20:53:10 +0200
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Subject: Re: [Xenomai] rtdm_lock_get
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>, Xenomai <xenomai@xenomai.org>

On 2015-09-19 13:26, Gilles Chanteperdrix wrote:
> Hi,
> 
> now that rtdm_lock_get() locks the scheduler, and if moved the
> scheduler lock before the spin_lock, would not it be possible to use
> rtdm_lock_get() with irqs on ?

Conceptually, yes. People will only have to be more carefully to use the
right mechanism depending on if there are IRQ-based users or not - just
like under Linux. We avoided this trap so far.

Maybe we should ask the user to mark IRQ-free spinlocks via a special
rtdm_lock_init_noirq. Then we could validate the caller's context in a
debug version.

Jan

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