Re: [PULL 04/47] util/oslib-win32: Use _aligned_malloc for qemu_try_memalign

[Volker Rümelin]

> We do not need or want to be allocating page sized quanta.
>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Reviewed-by: Stefan Weil <sw@weilnetz.de>
> Message-Id: <20201018164836.1149452-1-richard.henderson@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  util/oslib-win32.c | 11 ++++-------
>  1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/util/oslib-win32.c b/util/oslib-win32.c
> index 01787df74c..8adc651259 100644
> --- a/util/oslib-win32.c
> +++ b/util/oslib-win32.c
> @@ -39,6 +39,7 @@
>  #include "trace.h"
>  #include "qemu/sockets.h"
>  #include "qemu/cutils.h"
> +#include <malloc.h>
>  
>  /* this must come after including "trace.h" */
>  #include <shlobj.h>
> @@ -56,10 +57,8 @@ void *qemu_try_memalign(size_t alignment, size_t size)
>  {
>      void *ptr;
>  
> -    if (!size) {
> -        abort();
> -    }
> -    ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
> +    g_assert(size != 0);
> +    ptr = _aligned_malloc(alignment, size);

Hi Richard,

this doesn't work really well. The _aligned_malloc parameters are swapped. ptr 
= _aligned_malloc(size, alignment) is correct.

With best regards,
Volker

>      trace_qemu_memalign(alignment, size, ptr);
>      return ptr;
>  }
> @@ -93,9 +92,7 @@ void *qemu_anon_ram_alloc(size_t size, uint64_t *align, 
> bool shared)
>  void qemu_vfree(void *ptr)
>  {
>      trace_qemu_vfree(ptr);
> -    if (ptr) {
> -        VirtualFree(ptr, 0, MEM_RELEASE);
> -    }
> +    _aligned_free(ptr);
>  }
>  
>  void qemu_anon_ram_free(void *ptr, size_t size)