1612114 – Anonymous BlockBackends are missing in query-blockstats

RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 1612114 - Anonymous BlockBackends are missing in query-blockstats

Summary: Anonymous BlockBackends are missing in query-blockstats

Keywords:
Status:	CLOSED ERRATA
Alias:	None
Product:	Red Hat Enterprise Linux 7
Classification:	Red Hat
Component:	qemu-kvm-rhev
Sub Component:
Version:	7.6
Hardware:	Unspecified
OS:	Unspecified
Priority:	medium
Severity:	medium
Target Milestone:	rc
Target Release:	---
Assignee:	Kevin Wolf
QA Contact:	CongLi
Docs Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+	depends on / blocked

Reported:	2018-08-03 13:43 UTC by Kevin Wolf
Modified:	2018-11-01 11:15 UTC (History)
CC List:	14 users (show)
Fixed In Version:	qemu-kvm-rhev-2.12.0-10.el7
Doc Type:	If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed:	2018-11-01 11:13:16 UTC
Target Upstream Version:
Embargoed:

Attachments	(Terms of Use)

Links
System	ID	Private	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHBA-2018:3443	0	None	None	None	2018-11-01 11:15:34 UTC

Description Kevin Wolf 2018-08-03 13:43:44 UTC

If a block device is configured with -blockdev and -device rather than -drive (and therefore the associated BlockBackend doesn't have a -drive ID, but is anonymous), query-blockstats fails to list it.

Additionally, there is no way to unambiguously relate the stats without a BlockBackend name (which would be included as 'device'). Therefore, a new field 'qdev' is needed that contains the ID of the qdev device that the BlockBackend belongs to.

This is fixed in upstream commits 5a9cb5a97f and 567dcb31f2.

Comment 3 Miroslav Rezanina 2018-08-10 10:53:47 UTC

Fix included in qemu-kvm-rhev-2.12.0-10.el7

Comment 5 CongLi 2018-08-16 11:22:49 UTC

Verified this bug on: qemu-kvm-rhev-2.12.0-10.el7.x86_64


1. blockstats with -drive if=virtio  --> device is virtio, there is filed 'qdev' of virtio device: "qdev": "/machine/peripheral-anon/device[0]/virtio-backend" via 'query-blockstats', which same as 'query-block'.

QEMU CML: -drive driver=null-co,if=virtio
{ "execute": "query-blockstats"}
{
    "return": [
        {
            "device": "virtio0",
            "stats": {
                "flush_total_time_ns": 0,
                "wr_highest_offset": 0,
                "wr_total_time_ns": 0,
                "failed_wr_operations": 0,
                "failed_rd_operations": 0,
                "wr_merged": 0,
                "wr_bytes": 0,
                "timed_stats": [
                ],
                "failed_flush_operations": 0,
                "account_invalid": true,
                "rd_total_time_ns": 44141,
                "flush_operations": 0,
                "wr_operations": 0,
                "rd_merged": 0,
                "rd_bytes": 512,
                "invalid_flush_operations": 0,
                "account_failed": true,
                "idle_time_ns": 38804814834,
                "rd_operations": 1,
                "invalid_wr_operations": 0,
                "invalid_rd_operations": 0
            },
            "node-name": "#block022",
            "qdev": "/machine/peripheral-anon/device[0]/virtio-backend"
        },
...}

2. blockstats with -drive if=none  --> device is none, the output is same as 'query-block'.
QEMU CML: -drive driver=null-co,if=none
{ "execute": "query-blockstats"}
{
    "return": [
        {
            "device": "none0",
            "stats": {
                "flush_total_time_ns": 0,
                "wr_highest_offset": 0,
                "wr_total_time_ns": 0,
                "failed_wr_operations": 0,
                "failed_rd_operations": 0,
                "wr_merged": 0,
                "wr_bytes": 0,
                "timed_stats": [
                ],
                "failed_flush_operations": 0,
                "account_invalid": true,
                "rd_total_time_ns": 0,
                "flush_operations": 0,
                "wr_operations": 0,
                "rd_merged": 0,
                "rd_bytes": 0,
                "invalid_flush_operations": 0,
                "account_failed": true,
                "rd_operations": 0,
                "invalid_wr_operations": 0,
                "invalid_rd_operations": 0
            },
            "node-name": "#block099"
        },
...}

3. blockstats with -blockdev  --> no device info, which same as 'query-block'.
QEMU CML: -blockdev driver=null-co,node-name=null
{ "execute": "query-blockstats"}
{...}

4. blockstats with -blockdev and -device  --> device is null, there is filed 'qdev' of virtio device: "qdev": ""qdev": "/machine/peripheral/virtio0/virtio-backend"" via 'query-blockstats', which same as 'query-block'.
QEMU CML: -blockdev driver=null-co,node-name=null -device virtio-blk,drive=null,id=virtio0
{ "execute": "query-blockstats"}
{
    "return": [
        ...
        {
            "device": "",
            "stats": {
                "flush_total_time_ns": 0,
                "wr_highest_offset": 0,
                "wr_total_time_ns": 0,
                "failed_wr_operations": 0,
                "failed_rd_operations": 0,
                "wr_merged": 0,
                "wr_bytes": 0,
                "timed_stats": [
                ],
                "failed_flush_operations": 0,
                "account_invalid": false,
                "rd_total_time_ns": 42959,
                "flush_operations": 0,
                "wr_operations": 0,
                "rd_merged": 0,
                "rd_bytes": 512,
                "invalid_flush_operations": 0,
                "account_failed": false,
                "idle_time_ns": 40574708168,
                "rd_operations": 1,
                "invalid_wr_operations": 0,
                "invalid_rd_operations": 0
            },
            "node-name": "null",
            "qdev": "/machine/peripheral/virtio0/virtio-backend"
        }
    ]
}

qemu-iotests of 227 pass.
227        
Passed all 1 tests

Comment 6 errata-xmlrpc 2018-11-01 11:13:16 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:3443

Note You need to log in before you can comment on or make changes to this bug.