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Date: Tue, 16 Nov 2010 16:01:06 +0800
From: "Figo.zhang" <zhangtianfei@leadcoretech.com>
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To: Hans Verkuil <hverkuil@xs4all.nl>
CC: Andrew Chew <AChew@nvidia.com>,
	"'linux-media@vger.kernel.org'" <linux-media@vger.kernel.org>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Subject: Re: Allocating videobuf_buffer, but lists not being initialized
References: <643E69AA4436674C8F39DCC2C05F763816BB828A36@HQMAIL03.nvidia.com> <643E69AA4436674C8F39DCC2C05F763816BB828A37@HQMAIL03.nvidia.com> <201011160837.32797.hverkuil@xs4all.nl>
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于 11/16/2010 03:37 PM, Hans Verkuil 写道:
> On Tuesday, November 16, 2010 02:10:39 Andrew Chew wrote:
>> I'm looking at drivers/media/video/videobuf-dma-contig.c's __videobuf_alloc() routine.  We call kzalloc() to allocate the videobuf_buffer.  However, I don't see where the two lists (vb->stream and vb->queue) that are a part of struct videobuf_buffer get initialized (with, say, INIT_LIST_HEAD).
>
> Yuck. The videobuf framework doesn't initialize vb-stream at all. It relies on
> list_add_tail to effectively initialize it for it. It works, but it is not
> exactly clean programming :-(
>
> The vb->queue list has to be initialized in the driver. Never understood the
> reason for that either.
>
> Marek, can you make sure that videobuf2 will initialize these lists correctly?
> That is, vb2 should do this initialization instead of the driver.

vb2 have init the list :
	INIT_LIST_HEAD(&q->queued_list);
	INIT_LIST_HEAD(&q->done_list);

btw, "queued_list" re-name "grabbing_list" is better?