Re: [PATCH v2 for-4.6] libxl_set_memory_target: retain the same maxmem offset on top of the current target

[Don Slutz <dslutz@verizon.com>]

On 12/02/14 06:53, Stefano Stabellini wrote:
> In libxl_set_memory_target when setting the new maxmem, retain the same
> offset on top of the current target. The offset includes memory
> allocated by QEMU for rom files.
>
> Signed-off-by: Stefano Stabellini<stefano.stabellini@eu.citrix.com>
>
> ---
>
> Changes in v2:
> - call libxl_domain_info instead of libxl_dominfo_init;
> - call libxl_domain_info before retry_transaction.
>
> diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
> index de23fec..569a32a 100644
> --- a/tools/libxl/libxl.c
> +++ b/tools/libxl/libxl.c
> @@ -4694,6 +4694,9 @@ int libxl_set_memory_target(libxl_ctx *ctx, uint32_t domid,
>       char *uuid;
>       xs_transaction_t t;
>   
> +    if (libxl_domain_info(ctx, &ptr, domid) < 0)
> +        goto out_no_transaction;
> +
>   retry_transaction:
>       t = xs_transaction_start(ctx->xsh);
>   
> @@ -4767,10 +4770,9 @@ retry_transaction:
>                   "%s/memory/videoram", dompath));
>       videoram = videoram_s ? atoi(videoram_s) : 0;
>   
> -    if (enforce) {
> -        memorykb = new_target_memkb;
> -        rc = xc_domain_setmaxmem(ctx->xch, domid, memorykb +
> -                LIBXL_MAXMEM_CONSTANT);
> +    if (enforce && new_target_memkb > 0) {
> +        memorykb = ptr.max_memkb - current_target_memkb + new_target_memkb;
> +        rc = xc_domain_setmaxmem(ctx->xch, domid, memorykb);
>           if (rc != 0) {
>               LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR,
>                       "xc_domain_setmaxmem domid=%d memkb=%d failed "

You need to remove LIBXL_MAXMEM_CONSTANT here also.

    -Don Slutz


> @@ -4800,8 +4802,6 @@ retry_transaction:
>           goto out;
>       }
>   
> -    libxl_dominfo_init(&ptr);
> -    xcinfo2xlinfo(ctx, &info, &ptr);
>       uuid = libxl__uuid2string(gc, ptr.uuid);
>       libxl__xs_write(gc, t, libxl__sprintf(gc, "/vm/%s/memory", uuid),
>               "%"PRIu32, new_target_memkb / 1024);