At 2018-05-30 11:19:27, "Eric Blake" <ebl...@redhat.com> wrote:
>On 05/29/2018 10:01 PM, Chen Hanxiao wrote:
>> From: Chen Hanxiao <chenhanx...@gmail.com>
>>
>> This patch adds support for getting the usage of mounted
>> filesystem.
>> It's very useful when we try to monitor guest's filesystem.
>> Use df of coreutils for reference.
>>
>> Cc: Michael Roth <mdr...@linux.vnet.ibm.com>
>> Signed-off-by: Chen Hanxiao <chenhanx...@gmail.com>
>> ---
>
>> @@ -1072,6 +1073,9 @@ static GuestFilesystemInfo *build_guest_fsinfo(struct
>> FsMount *mount,
>> Error **errp)
>> {
>> GuestFilesystemInfo *fs = g_malloc0(sizeof(*fs));
>> + struct statvfs buf;
>> + unsigned long u100, used, nonroot_total;
>> + int usage;
>> char *devpath = g_strdup_printf("/sys/dev/block/%u:%u",
>> mount->devmajor, mount->devminor);
>>
>> @@ -1079,7 +1083,20 @@ static GuestFilesystemInfo *build_guest_fsinfo(struct
>> FsMount *mount,
>> fs->type = g_strdup(mount->devtype);
>> build_guest_fsinfo_for_device(devpath, fs, errp);
>>
>> + if (statvfs(fs->mountpoint, &buf)) {
>> + error_setg_errno(errp, errno, "Failed to get statvfs");
>> + return NULL;
>> + }
>> +
>> + used = buf.f_blocks - buf.f_bfree;
>> + u100 = 100 * used;
>> + nonroot_total = used + buf.f_bavail;
>> + usage = u100 / nonroot_total + (u100 % nonroot_total != 0);
>
>Why integral instead of floating point?
I followed the style of df from coreutils.
As the percentage already multiplied by 100,
I think it has enough precision.
>
>> +++ b/qga/qapi-schema.json
>> @@ -846,13 +846,14 @@
>> # @name: disk name
>> # @mountpoint: mount point path
>> # @type: file system type string
>> +# @usage: file system usage
>
>Needs more details. As written, it is an integer between 0 and 100; but
>if you use floating point, a better description would be a fraction
>between 0 and 1.
Will be updated in the following patch.
Regards,
- Chen
>
>> # @disk: an array of disk hardware information that the volume lies on,
>> # which may be empty if the disk type is not supported
>> #
>> # Since: 2.2
>> ##
>> { 'struct': 'GuestFilesystemInfo',
>> - 'data': {'name': 'str', 'mountpoint': 'str', 'type': 'str',
>> + 'data': {'name': 'str', 'mountpoint': 'str', 'type': 'str', 'usage':
>> 'int',
>> 'disk': ['GuestDiskAddress']} }
>>
>> ##
>>
>
>--
>Eric Blake, Principal Software Engineer
>Red Hat, Inc. +1-919-301-3266
>Virtualization: qemu.org | libvirt.org
