From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kyle McMartin <kyle@mcmartin.ca>
Subject: Re: [patch] brd: support discard
Date: Thu, 27 May 2010 07:28:05 -0400
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References: <20100526133342.GA22536@laptop>
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Cc: Jens Axboe <jens.axboe@oracle.com>, linux-fsdevel@vger.kernel.org
To: Nick Piggin <npiggin@suse.de>
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On Wed, May 26, 2010 at 11:33:42PM +1000, Nick Piggin wrote:
> +static void discard_from_brd(struct brd_device *brd,
> +			sector_t sector, size_t n)
> +{
> +	while (n >= PAGE_SIZE) {
> +		/*
> +		 * Don't want to actually discard pages here because
> +		 * re-allocating the pages can result in writeback
> +		 * deadlocks under heavy load.
> +		 */
> +		if (0)
> +			brd_free_page(brd, sector);
> +		else
> +			brd_zero_page(brd, sector);

That if (0) looks a little suspicious... ;-)

regards, Kyle