[libvirt] [PATCH 11/21] conf: Format cache banks in capabilities with virPrettySize

[John Ferlan]

On 11/13/2017 03:50 AM, Martin Kletzander wrote:
> Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
> ---
>  src/conf/capabilities.c                            | 45 ++++++++++++++--------
>  tests/vircaps2xmldata/vircaps-x86_64-caches.xml    |  2 +-
>  .../vircaps2xmldata/vircaps-x86_64-resctrl-cdp.xml |  4 +-
>  .../vircaps2xmldata/vircaps-x86_64-resctrl-skx.xml |  4 +-
>  tests/vircaps2xmldata/vircaps-x86_64-resctrl.xml   |  4 +-
>  5 files changed, 36 insertions(+), 23 deletions(-)
> 

Reviewed-by: John Ferlan <jferlan at redhat.com>

John

couple of noisy review thoughts below...


> diff --git a/src/conf/capabilities.c b/src/conf/capabilities.c
> index 095ef51c424a..5bf8ac2019f9 100644
> --- a/src/conf/capabilities.c
> +++ b/src/conf/capabilities.c
> @@ -883,7 +883,8 @@ virCapabilitiesFormatCaches(virBufferPtr buf,
>      for (i = 0; i < ncaches; i++) {
>          virCapsHostCacheBankPtr bank = caches[i];
>          char *cpus_str = virBitmapFormat(bank->cpus);
> -        bool kilos = !(bank->size % 1024);
> +        const char *unit = NULL;
> +        unsigned long long short_size = virPrettySize(bank->size, &unit);
>  
>          if (!cpus_str)
>              return -1;
> @@ -897,32 +898,44 @@ virCapabilitiesFormatCaches(virBufferPtr buf,
>                            "size='%llu' unit='%s' cpus='%s'",
>                            bank->id, bank->level,
>                            virCacheTypeToString(bank->type),
> -                          bank->size >> (kilos * 10),
> -                          kilos ? "KiB" : "B",
> -                          cpus_str);
> +                          short_size, unit, cpus_str);
>          VIR_FREE(cpus_str);
>  
>          virBufferSetChildIndent(&controlBuf, buf);
>          for (j = 0; j < bank->ncontrols; j++) {

You could have "virResctrlInfoPtr controls = bank->controls[j];"

> -            bool min_kilos = !(bank->controls[j]->granularity % 1024);
> -
> -            /* Only use KiB if both values are divisible */
> -            if (bank->controls[j]->min)
> -                min_kilos = min_kilos && !(bank->controls[j]->min % 1024);
> +            const char *min_unit;
> +            unsigned long long gran_short_size = bank->controls[j]->granularity;
> +            unsigned long long min_short_size = bank->controls[j]->min;
> +
> +            gran_short_size = virPrettySize(gran_short_size, &unit);
> +            min_short_size = virPrettySize(min_short_size, &min_unit);
> +
> +            /* Only use the smaller unit if they are different */

Or "if (STRNEQ(unit, min_unit))" - to be more faithful to the comment! I
read this as - if min_short_size is there, then we check the unit by
knowing the math to get the value.

To some degree if the pretty format function allowed one to "choose" a
specific format size that'd perhaps work too, but that's perhaps more
work than it's worth.

> +            if (min_short_size) {
> +                unsigned long long gran_div;
> +                unsigned long long min_div;
> +
> +                gran_div = bank->controls[j]->granularity / gran_short_size;
> +                min_div = bank->controls[j]->min / min_short_size;
> +
> +                if (min_div > gran_div) {
> +                    min_short_size *= min_div / gran_div;
> +                } else if (min_div < gran_div) {
> +                    unit = min_unit;
> +                    gran_short_size *= gran_div / min_div;
> +                }
> +            }
>  
>              virBufferAsprintf(&controlBuf,
>                                "<control granularity='%llu'",
> -                              bank->controls[j]->granularity >> (min_kilos * 10));
> +                              gran_short_size);
>  
> -            if (bank->controls[j]->min) {
> -                virBufferAsprintf(&controlBuf,
> -                                  " min='%llu'",
> -                                  bank->controls[j]->min >> (min_kilos * 10));
> -            }
> +            if (min_short_size)
> +                virBufferAsprintf(&controlBuf, " min='%llu'", min_short_size);
>  
>              virBufferAsprintf(&controlBuf,
>                                " unit='%s' type='%s' maxAllocs='%u'/>\n",
> -                              min_kilos ? "KiB" : "B",
> +                              unit,
>                                virCacheTypeToString(bank->controls[j]->scope),
>                                bank->controls[j]->max_allocation);
>          }
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