OS-7104: export hrtime params for pvclock impls

Details

Issue Type:Improvement
Priority:4 - Normal
Status:Resolved
Created at:2018-08-06T15:06:19.201Z
Updated at:2018-08-21T22:02:05.376Z

People

Created by:Former user
Reported by:Former user
Assigned to:Former user

Resolution

Fixed: A fix for this issue is checked into the tree and tested.
(Resolution Date: 2018-08-21T22:02:05.367Z)

Fix Versions

2018-08-30 Zolom Swamp (Release Date: 2018-08-30)

Description

The pvclock implementations described in OS-6949 and OS-7102 require knowledge of the TSC scale/shift parameters in order to present their expected interface to the guest. For the near-term, it probably makes sense to do so via a more expressive tsc_gethrtime_* variant, leaving us room in the future to refine that os-internal interface.

Comments

Comment by Former user
Created at 2018-08-08T17:47:41.714Z

I tested this with the pending changes for OS-7102 (its only consumer for the time being) on node with synced TSCs (westmere) and one with skewed TSCs (IvyB, where we reset TSCs during boot due to errata). On both nodes, a Linux guest running in KVM is able to establish a stable NTP fix using the kvm-clock data as its clocksource.


Comment by Jira Bot
Created at 2018-08-21T21:59:35.085Z

illumos-joyent commit 103b229de957139cb321fefcbee9fa8ae3b0fbba (branch master, by Patrick Mooney)

OS-7104 export hrtime params for pvclock impls
Reviewed by: John Levon <john.levon@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Mike Gerdts <mike.gerdts@joyent.com>
Approved by: Mike Gerdts <mike.gerdts@joyent.com>