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Date: Fri, 07 Feb 2014 15:38:29 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai] High CPU load using q_send under pSOS skin
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To: Marcel van Mierlo <marcel.vanmierlo@marel.com>
Cc: xenomai@xenomai.org

On 02/07/2014 03:32 PM, Marcel van Mierlo wrote:
> If I comment out q_send TRAP 8 dosent occur. If I pass NULL as data
> words to q_send, TRAP 8 stops... and %CPU remains low....hmmm do I need
> to ensure stack alignment somehow?

The stack alignment is ensured by the compiler. Starting with ARM EABI, 
the stack is aligned on 8 bytes, so, if you do not use special tricks 
(like casting a char * pointer to a u_long *pointer, or using 
__attribute__((packed))), everything should be aligned properly. Could 
you show us the declaration of the buffer passed to q_send ? In fact, 
posting a self-contained, minimal example allowing to reproduce the 
problem would help.

-- 
					    Gilles.