Close T-GM and T-BC phc2sys clock synchronization race conditions#619
Close T-GM and T-BC phc2sys clock synchronization race conditions#619lack wants to merge 1 commit into
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Synchronizing the system clock too early can lead to large time offsets that settle slowly. By delaying phc2sys from running until the PHC is "reasonably synchronized" (ie within 1.0s offset of a trusted timesource), we ensure small offsets only which converge quickly. For OC and BC, this means delaying phc2sys until ptp4l offset is <1.0s (and in the case of mutli-profile BC, choosing the proper ptp4l to evaluate is key). In GM, we delay phc2sys until ts2phc offset is <1.0s. Cherry-picked from OCPBUGS-85586_phc2sys_ts2phc_race-4.22 (d2ff2d1) and adapted for the 4.21 codebase (no hardwareconfig, alias, or v2alpha1 APIs). Fixes: OCPBUGS-85586 Assisted-by: Claude Opus 4.6 and pi.dev Signed-off-by: Jim Ramsay <jramsay@redhat.com>
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Synchronizing the system clock too early can lead to large time offsets
that settle slowly. By delaying phc2sys from running until the PHC is
"reasonably synchronized" (ie within 1.0s offset of a trusted
timesource), we ensure small offsets only which converge quickly.
For OC and BC, this means delaying phc2sys until ptp4l offset is <1.0s
(and in the case of mutli-profile BC, choosing the proper ptp4l to
evaluate is key). In GM, we delay phc2sys until ts2phc offset is <1.0s.
Cherry-picked from OCPBUGS-85586_phc2sys_ts2phc_race-4.22 (d2ff2d1)
and adapted for the 4.21 codebase (no hardwareconfig, alias, or
v2alpha1 APIs).
Fixes: OCPBUGS-85586
Assisted-by: Claude Opus 4.6 and pi.dev
Signed-off-by: Jim Ramsay jramsay@redhat.com