On Tue, Apr 14, 2009 at 08:20:49PM +0200, Jens Axboe wrote:
>
> It's a bio_alloc() guarantee, it uses a mempool backing. And if you use
> a mempool backing, any allocation that can wait will always be
> satisfied.
>
Am I missing something? I don't see anything in
include/linux/mempool.h or mm/mempool.c, or in block/blk-core.c or
include/linux/bio.h which documents that GFP_WAIT implies that
bio_alloc() will always succeed.
My concern is that at some point in the future, someone either in the
block device layer or in mm/mempool.c will consider this an
implementation detail, and all of sudden calls to bio_alloc() with
GFP_WAIT will start failing and the resulting hilarty which ensues
won't be easily predicted by the developer making this change.
Regards,
- Ted
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