[libvirt] [PATCHv3] Add util virCgroupGetBlkioIo*Serviced methods.

[Gao feng]

On 01/20/2014 08:15 PM, Thorsten Behrens wrote:
> This reads blkio stats from blkio.throttle.io_service_bytes and
> blkio.throttle.io_serviced.
> ---
> 
> Note on v3:
>  - rebased to current master, sadly the
>    virCgroupSetBlkioDeviceReadBps etc conflicted
> 
>  src/libvirt_private.syms |   2 +
>  src/util/vircgroup.c     | 242 +++++++++++++++++++++++++++++++++++++++++++++++
>  src/util/vircgroup.h     |  12 +++
>  3 files changed, 256 insertions(+)
> 
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index 3ede3d5..1e44ed8 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -1002,6 +1002,8 @@ virCgroupDenyDevice;
>  virCgroupDenyDeviceMajor;
>  virCgroupDenyDevicePath;
>  virCgroupFree;
> +virCgroupGetBlkioIoDeviceServiced;
> +virCgroupGetBlkioIoServiced;
>  virCgroupGetBlkioWeight;
>  virCgroupGetCpuacctPercpuUsage;
>  virCgroupGetCpuacctStat;
> diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
> index a6d60c5..2b70bcb 100644
> --- a/src/util/vircgroup.c
> +++ b/src/util/vircgroup.c
> @@ -1786,6 +1786,221 @@ virCgroupPathOfController(virCgroupPtr group,
>  
>  
>  /**
> + * virCgroupGetBlkioIoServiced:
> + *
> + * @group: The cgroup to get throughput for
> + * @bytes_read: Pointer to returned bytes read
> + * @bytes_write: Pointer to returned bytes written
> + * @requests_read: Pointer to returned read io ops
> + * @requests_write: Pointer to returned write io ops
> + *
> + * Returns: 0 on success, -1 on error
> + */
> +int
> +virCgroupGetBlkioIoServiced(virCgroupPtr group,
> +                            long long *bytes_read,
> +                            long long *bytes_write,
> +                            long long *requests_read,
> +                            long long *requests_write)
> +{
> +    long long stats_val;
> +    char *str1 = NULL, *str2 = NULL, *p1, *p2;
> +    size_t i;
> +    int ret = -1;
> +
> +    const char *value_names[] = {
> +        "Read ",
> +        "Write "
> +    };
> +    long long *bytes_ptrs[] = {
> +        bytes_read,
> +        bytes_write
> +    };
> +    long long *requests_ptrs[] = {
> +        requests_read,
> +        requests_write
> +    };
> +
> +    *bytes_read = 0;
> +    *bytes_write = 0;
> +    *requests_read = 0;
> +    *requests_write = 0;
> +
> +    if (virCgroupGetValueStr(group,
> +                             VIR_CGROUP_CONTROLLER_BLKIO,
> +                             "blkio.throttle.io_service_bytes", &str1) < 0)
> +        goto cleanup;
> +
> +    if (virCgroupGetValueStr(group,
> +                             VIR_CGROUP_CONTROLLER_BLKIO,
> +                             "blkio.throttle.io_serviced", &str2) < 0)
> +        goto cleanup;
> +
> +    /* sum up all entries of the same kind, from all devices */
> +    for (i = 0; i < ARRAY_CARDINALITY(value_names); i++) {
> +        p1 = str1;
> +        p2 = str2;
> +
> +        while ((p1 = strstr(p1, value_names[i]))) {
> +            p1 += strlen(value_names[i]);
> +            if (virStrToLong_ll(p1, &p1, 10, &stats_val) < 0) {
> +                virReportError(VIR_ERR_INTERNAL_ERROR,
> +                               _("Cannot parse byte %sstat '%s'"),
> +                               value_names[i],
> +                               p1);
> +                goto cleanup;
> +            }
> +
> +            if (stats_val < 0 ||
> +                (stats_val > 0 && *bytes_ptrs[i] > (LLONG_MAX - stats_val)))
> +            {
> +                virReportError(VIR_ERR_OVERFLOW,
> +                               _("Sum of byte %sstat overflows"),
> +                               value_names[i]);
> +                goto cleanup;
> +            }
> +            *bytes_ptrs[i] += stats_val;
> +        }
> +
> +        while ((p2 = strstr(p2, value_names[i]))) {
> +            p2 += strlen(value_names[i]);
> +            if (virStrToLong_ll(p2, &p2, 10, &stats_val) < 0) {
> +                virReportError(VIR_ERR_INTERNAL_ERROR,
> +                               _("Cannot parse %srequest stat '%s'"),
> +                               value_names[i],
> +                               p2);
> +                goto cleanup;
> +            }
> +
> +            if (stats_val < 0 ||
> +                (stats_val > 0 && *requests_ptrs[i] > (LLONG_MAX - stats_val)))
> +            {
> +                virReportError(VIR_ERR_OVERFLOW,
> +                               _("Sum of %srequest stat overflows"),
> +                               value_names[i]);
> +                goto cleanup;
> +            }
> +            *requests_ptrs[i] += stats_val;
> +        }
> +    }
> +
> +    ret = 0;
> +
> +cleanup:
> +    VIR_FREE(str2);
> +    VIR_FREE(str1);
> +    return ret;
> +}
> +
> +
> +/**
> + * virCgroupGetBlkioIoDeviceServiced:
> + *
> + * @group: The cgroup to get throughput for
> + * @path: The device to get throughput for
> + * @bytes_read: Pointer to returned bytes read
> + * @bytes_write: Pointer to returned bytes written
> + * @requests_read: Pointer to returned read io ops
> + * @requests_write: Pointer to returned write io ops
> + *
> + * Returns: 0 on success, -1 on error
> + */
> +int
> +virCgroupGetBlkioIoDeviceServiced(virCgroupPtr group,
> +                                  const char *path,
> +                                  long long *bytes_read,
> +                                  long long *bytes_write,
> +                                  long long *requests_read,
> +                                  long long *requests_write)
> +{
> +    char *str1 = NULL, *str2 = NULL, *str3 = NULL, *p;
> +    struct stat sb;
> +    size_t i;
> +    int ret = -1;
> +
> +    const char *value_names[] = {
> +        "Read ",
> +        "Write "
> +    };
> +    long long *bytes_ptrs[] = {
> +        bytes_read,
> +        bytes_write
> +    };
> +    long long *requests_ptrs[] = {
> +        requests_read,
> +        requests_write
> +    };
> +
> +    if (stat(path, &sb) < 0) {
> +        virReportSystemError(errno,
> +                             _("Path '%s' is not accessible"),
> +                             path);
> +        return -1;
> +    }
> +
> +    if (!S_ISBLK(sb.st_mode)) {
> +        virReportSystemError(EINVAL,
> +                             _("Path '%s' must be a block device"),
> +                             path);
> +        return -1;
> +    }
> +
> +    if (virCgroupGetValueStr(group,
> +                             VIR_CGROUP_CONTROLLER_BLKIO,
> +                             "blkio.throttle.io_service_bytes", &str1) < 0)
> +        goto cleanup;
> +
> +    if (virCgroupGetValueStr(group,
> +                             VIR_CGROUP_CONTROLLER_BLKIO,
> +                             "blkio.throttle.io_serviced", &str2) < 0)
> +        goto cleanup;
> +
> +    if (virAsprintf(&str3, "%d:%d ", major(sb.st_rdev), minor(sb.st_rdev)) < 0)
> +        goto cleanup;
> +
> +    if (!(p = strstr(str1, str3))) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR,
> +                       _("Cannot find byte stats for block device '%s'"),
> +                       p);


path?

> +        goto cleanup;
> +    }
> +
> +    if (!(p = strstr(str2, str3))) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR,
> +                       _("Cannot find request stats for block device '%s'"),
> +                       p);

here too;

> +        goto cleanup;
> +    }
> +
> +    for (i = 0; i < ARRAY_CARDINALITY(value_names); i++) {
> +        if (!(p = strstr(p, value_names[i])) ||
> +            virStrToLong_ll(p + strlen(value_names[i]), &p, 10, bytes_ptrs[i]) < 0) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR,
> +                           _("Cannot parse stat '%s'"),
> +                           p + strlen(value_names[i]));

p may null here.

> +            goto cleanup;
> +        }
> +
> +        if (!(p = strstr(p, value_names[i])) ||
> +            virStrToLong_ll(p + strlen(value_names[i]), &p, 10, requests_ptrs[i]) < 0) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR,
> +                           _("Cannot parse stat '%s'"),
> +                           p + strlen(value_names[i]));

here too;

ACK with these changed.