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Date: Fri, 26 Sep 2008 10:37:54 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Arnaldo Carvalho de Melo <acme@redhat.com>
cc: Steven Rostedt <rostedt@goodmis.org>,
       Masami Hiramatsu <mhiramat@redhat.com>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
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       hch@lst.de, Martin Bligh <mbligh@google.com>,
       Christoph Hellwig <hch@infradead.org>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [PATCH v5] Unified trace buffer
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On Fri, 26 Sep 2008, Arnaldo Carvalho de Melo wrote:
> 
> Why do you need __packed__ here? With or without it the layout is the
> same:

Indeed. And on some architectures 'packed' will actually mean that the 
compiler may think that it's unaligned, and then generate much worse code 
to access the fields. So if you align things anyway (and you do), then 
'packed' is the wrong thing to do.

		Linus