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Date: Wed, 10 Jun 2009 23:35:16 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
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To: Lai Jiangshan <laijs@cn.fujitsu.com>
cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
       Andrew Morton <akpm@linux-foundation.org>,
       Thomas Gleixner <tglx@linutronix.de>,
       Peter Zijlstra <peterz@infradead.org>,
       Frederic Weisbecker <fweisbec@gmail.com>, Theodore Tso <tytso@mit.edu>,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       Mathieu Desnoyers <compudj@krystal.dyndns.org>,
       "Martin J. Bligh" <mbligh@mbligh.org>,
       Christoph Hellwig <hch@infradead.org>, Li Zefan <lizf@cn.fujitsu.com>,
       Huang Ying <ying.huang@intel.com>, "H. Peter Anvin" <hpa@zytor.com>,
       Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>,
       Masami Hiramatsu <mhiramat@redhat.com>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [PATCH 1/3] ring-buffer: make the buffer a true circular link
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On Thu, 11 Jun 2009, Lai Jiangshan wrote:
> 
> I'm not sure whether these 4 lines:
> 	bpage = list_entry(pages.next, struct buffer_page, list);
> 	list_del_init(&bpage->list);
> 	cpu_buffer->pages = &bpage->list;
> 
> 	list_splice(&pages, cpu_buffer->pages);

> equal to these 2 lines:
>  	cpu_buffer->pages = pages.next;
>  	list_del(&pages);
> 
> If there are equivalent, I think the second one
> are simpler. It may be not a really necessarily cleanup.
> 
> What I asked is: if there are equivalent, could you use these two line:
>  	cpu_buffer->pages = pages.next;
>  	list_del(&pages);

OK, now I understand.

Hmm, that may be so. I'll have to look deeper at that.

Thanks,

-- Steve