Re: [vNUMA v2][PATCH 1/8] Config options

[Andre Przywara <andre.przywara@amd.com>]

Dulloor wrote:
> Implement the following config options :
> 
> strategy = "str", where str is confine/stripe/split/auto
> vnodes = <num-nodes>
> stripesz = <size-in-pages>
As Ian already said, I'd also prefer NUMA related names instead of
the generic "strategy". Also "vnodes" may be a bit misleading, what about
"guestnodes"?

> +typedef struct xc_domain_numa_config
> +{
> +    uint32_t strategy;      /* By default, DONTCARE (for now) */
> +    uint32_t nr_nodes;      /* For SPLIT/STRIPE */
> +    uint32_t stripe_size;   /* For STRIPE only */
Are 32 bit here sufficient? Although for the stripe size probably 4GB
are more than needed, I'd prefer to use 64bit (or long) for each
memory-related variable.
> +} xc_domain_numa_config_t;
> +

> +++ b/tools/libxl/xl_cmdimpl.c
> +static uint32_t numa_str_to_val(const char *str)
> +{
> +    if (!strcasecmp(str, "AUTO"))
> +        return XC_DOM_NUMA_AUTO;
> +    if (!strcasecmp(str, "CONFINE"))
> +        return XC_DOM_NUMA_CONFINE;
> +    if (!strcasecmp(str, "SPLIT"))
> +        return XC_DOM_NUMA_SPLIT;
> +    if (!strcasecmp(str, "STRIPE"))
> +        return XC_DOM_NUMA_STRIPE;
> +
> +    return XC_DOM_NUMA_NONE;
Shouldn't the function return something like "unknown" here?
This would allow to detect typos in the config file.

> @@ -650,6 +686,14 @@ static void parse_config_data(const char
>      if (!xlu_cfg_get_long (config, "videoram", &l))
>          b_info->video_memkb = l * 1024;
>  
> +    if (!xlu_cfg_get_string (config, "strategy", &buf)) {
> +        b_info->numa_config.strategy = numa_str_to_val(buf);
Here one chould check the returned value for "unknown" to detect
illegal strategy types.
> +        if (!xlu_cfg_get_long (config, "vnodes", &l))
> +            b_info->numa_config.nr_nodes = l;
> +        if (!xlu_cfg_get_long (config, "stripesz", &l))
> +            b_info->numa_config.stripe_size = l;
> +    }
> +
>      if (!xlu_cfg_get_string (config, "kernel", &buf))
>          b_info->kernel.path = strdup(buf);
>  

Regards,
Andre.

-- 
Andre Przywara
AMD-Operating System Research Center (OSRC), Dresden, Germany
Tel: +49 351 448-3567-12