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From: Scott Wood <scottwood@freescale.com>
To: Alex Zeffertt <ajz@cambridgebroadband.com>
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: local_irq_save not masking interrupts
Date: Tue, 26 Sep 2006 11:27:04 -0500	[thread overview]
Message-ID: <451954D8.3050909@freescale.com> (raw)
In-Reply-To: <45195296.8000405@cambridgebroadband.com>

Alex Zeffertt wrote:
> I agree this indicates an intent to make it atomic, but I don't see how
> this could cause interrupts to become re-enabled during the request_irq()
> call.  Also, since I am calling request_irq at insmod time, i.e. in process
> context, both GFP_ flags *should* work.

You're effectively not in process context when you disable IRQs (at 
least, if you want them to stay that way).  By specifying GFP_KERNEL, 
you're giving the allocator permission to go to sleep, enable IRQs, etc. 
  The IRQ enabling will happen any time cache_grow() is called with 
GFP_WAIT (which is part of GFP_KERNEL), assuming a growable slab.

-Scott

  reply	other threads:[~2006-09-26 16:27 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-09-26 10:00 local_irq_save not masking interrupts Alex Zeffertt
2006-09-26 10:19 ` Liu Dave-r63238
2006-09-26 10:28   ` Alex Zeffertt
2006-09-26 16:02     ` Scott Wood
2006-09-26 16:17       ` Alex Zeffertt
2006-09-26 16:27         ` Scott Wood [this message]
2006-09-26 16:42           ` Alex Zeffertt
2006-09-26 16:52             ` Scott Wood
2006-09-27 16:52 ` Esben Nielsen

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