[libvirt] [PATCH 16/17] vircgroup: Introduce virCgroupGetMemoryStat

[Michal Privoznik]

On 08/09/2018 03:44 PM, Pavel Hrdina wrote:
> Signed-off-by: Pavel Hrdina <phrdina at redhat.com>
> ---
>  src/libvirt_private.syms |  1 +
>  src/util/vircgroup.c     | 88 ++++++++++++++++++++++++++++++++++++++++
>  src/util/vircgroup.h     |  7 ++++
>  3 files changed, 96 insertions(+)
> 
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index 59d9bc380e..ee0dca6129 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -1532,6 +1532,7 @@ virCgroupGetDomainTotalCpuStats;
>  virCgroupGetFreezerState;
>  virCgroupGetMemoryHardLimit;
>  virCgroupGetMemorySoftLimit;
> +virCgroupGetMemoryStat;
>  virCgroupGetMemoryUsage;
>  virCgroupGetMemSwapHardLimit;
>  virCgroupGetMemSwapUsage;
> diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
> index 37982a9607..b91acd13c7 100644
> --- a/src/util/vircgroup.c
> +++ b/src/util/vircgroup.c
> @@ -2427,6 +2427,94 @@ virCgroupSetMemory(virCgroupPtr group, unsigned long long kb)
>  }
>  
>  
> +/**
> + * virCgroupGetMemoryStat:
> + *
> + * @group: The cgroup to change memory for
> + * @cache: page cache memory in KiB
> + * @activeAnon: anonymous and swap cache memory in KiB
> + * @inactiveAnon: anonymous and swap cache memory in KiB
> + * @activeFile: file-backed memory in KiB
> + * @inactiveFile: file-backed memory in KiB
> + * @unevictable: memory that cannot be reclaimed KiB
> + *
> + * Returns: 0 on success, -1 on error
> + */
> +int
> +virCgroupGetMemoryStat(virCgroupPtr group,
> +                       unsigned long long *cache,
> +                       unsigned long long *activeAnon,
> +                       unsigned long long *inactiveAnon,
> +                       unsigned long long *activeFile,
> +                       unsigned long long *inactiveFile,
> +                       unsigned long long *unevictable)
> +{
> +    int ret = -1;
> +    char *stat = NULL;
> +    char *line = NULL;
> +    unsigned long long cacheVal = 0;
> +    unsigned long long activeAnonVal = 0;
> +    unsigned long long inactiveAnonVal = 0;
> +    unsigned long long activeFileVal = 0;
> +    unsigned long long inactiveFileVal = 0;
> +    unsigned long long unevictableVal = 0;
> +
> +    if (virCgroupGetValueStr(group,
> +                             VIR_CGROUP_CONTROLLER_MEMORY,
> +                             "memory.stat",
> +                             &stat) < 0) {
> +        return -1;
> +    }
> +
> +    line = stat;
> +
> +    while (line) {
> +        char *newLine = strchr(line, '\n');
> +        char *valueStr = strchr(line, ' ');
> +        unsigned long long value;
> +
> +        if (newLine)
> +            *newLine = '\0';
> +
> +        if (!valueStr) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                           _("Cannot parse 'memory.stat' cgroup file."));
> +            goto cleanup;
> +        }
> +        *valueStr = '\0';
> +
> +        if (virStrToLong_ull(valueStr + 1, NULL, 10, &value) < 0)
> +            goto cleanup;
> +
> +        if (STREQ(line, "cache"))
> +            cacheVal = value >> 10;


Can't we assign directly to *cache? Sure, you'd need to initialize it
before, just like you're initializing cacheVal.

Michal