Re: [PATCH v2 1/9] block/io: refactor bdrv_is_allocated_above to run only one coroutine

[Eric Blake]

On 4/27/20 9:38 AM, Vladimir Sementsov-Ogievskiy wrote:
> bdrv_is_allocated_above creates new coroutine on each iteration if
> called from non-coroutine context. To simplify expansion of in_flight
> inc/dec sections in further patch let's refactor it.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> ---
>   block/io.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++----
>   1 file changed, 71 insertions(+), 5 deletions(-)

Quite a lot of lines added, but it fits the the mechanical boilerplate 
we have elsewhere.

> diff --git a/block/io.c b/block/io.c
> index aba67f66b9..94ab8eaa0f 100644
> --- a/block/io.c
> +++ b/block/io.c

> +int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
> +                            bool include_base, int64_t offset, int64_t bytes,
> +                            int64_t *pnum)
> +{
> +    Coroutine *co;
> +    BdrvCoIsAllocatedAboveData data = {
> +        .top = top,
> +        .base = base,
> +        .include_base = include_base,
> +        .offset = offset,
> +        .bytes = bytes,
> +        .pnum = pnum,
> +        .done = false,
> +    };

Omitting the line '.done = false,' has the same effect, since once you 
use a designated initializer, all remaining unspecified fields are 
0-initialized.  But explicitly mentioning it doesn't hurt.

Reviewed-by: Eric Blake <address@hidden>

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Eric Blake, Principal Software Engineer
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