Re: [Qemu-devel] [Qemu-block] [PATCH] block: Swap request limit definitions

[Alberto Garcia]

On Mon 13 Feb 2017 06:13:38 PM CET, Max Reitz wrote:

>>> -#define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
>>> -                                     INT_MAX >> BDRV_SECTOR_BITS)
>>> -#define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << 
>>> BDRV_SECTOR_BITS)
>>> +#define BDRV_REQUEST_MAX_BYTES      MIN(SIZE_MAX, INT_MAX)
>>> +#define BDRV_REQUEST_MAX_SECTORS    (BDRV_REQUEST_MAX_BYTES >> 
>>> BDRV_SECTOR_BITS)
>> 
>> I'm just pointing it out because I don't know if this can cause
>> problems, but this patch would make BDRV_REQUEST_MAX_BYTES not a
>> multiple of the sector size (INT_MAX is actually a prime number).
>
> Very good point. I don't think this could be an issue, though. For one
> thing, the use of BDRV_REQUEST_MAX_BYTES is very limited.

Ok, but then I wonder what's the benefit of increasing
BDRV_REQUEST_MAX_BYTES.

Berto