Re: [PATCH 0/5] qom: Allow object to be aligned

[Stefan Weil]

Am 16.09.20 um 00:47 schrieb Richard Henderson:

> On 9/15/20 10:46 AM, Richard Henderson wrote:
>> We already have a function that can alloc with alignment,
>> but we need to pass this down from the structure.  We also
>> don't want to use this function unconditionally, because
>> the windows version does page allocation, which would be
>> overkill for the vast majority of the objects allocated.
> Stefan, why are we using VirtualAlloc in util/oslib-win32.c, 
> qemu_try_memalign,
> instead of _aligned_malloc?


I think we use it because Fabrice introduced VirtualAlloc in commit
6e4255f6a65091fbe7d17bfda546e2aa1b72f9a6 (with a comment "FIXME: this is
not exactly optimal solution [...]"). Maybe there was no _aligned_malloc
available 15 years ago. Commit 33f002714be2ed58ed05ae3870d5ea6915df4b47
then reused VirtualAlloc for qemu_try_memalign (without a FIXME comment).

Obviously nobody cared to find a better solution until now.

Stefan