From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Fri, 27 Feb 2015 21:24:53 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Message-ID: <20150227202453.GK434@hermes.click-hack.org>
References: <54F0CF9E.1040707@siemens.com>
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Subject: Re: [Xenomai] [RFC] Consolidated exception prologue/epiloge for x86
 and ARM
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Xenomai <xenomai@xenomai.org>

On Fri, Feb 27, 2015 at 09:12:14PM +0100, Jan Kiszka wrote:
> Hi,
> 
> just pushed a first implementation of the general model that I proposed
> for exception handling. You can find it at
> 
> http://git.xenomai.org/ipipe-jki.git/log/?h=queues/trap-rework

NACK. The ARM implementation is broken, re-enabling hardware irqs
before stalling root is wrong.

Besides, I find that


if (foo) {
   bar;
} else {
  qux;
}

When there is nothing after adds useless indentation.

if (foo) {
   bar;
   return;
}

qux;

is much clearer.

Both thins were handled correctly in the implementation I proposed.
Also, reading your implementation as patches makes things uselessly
hard to read.

Simply posting the prologue and epilogue code would have made things
simpler.


> 
> I can also relay the patches to the list if desired.
> 
> Besides the issue that Gilles remarked, I found no further problems
> while implementing and testing this approach on both x86-64 and ARMv7.
> 
> I also added support for hardware breakpoint handling on ARM at this
> chance but I didn't test that particular path yet.

As you had been warned, your tests were useless since I disagree
with your implementation.

-- 
					    Gilles.