Description of problem:
The ktimersoftirq is waking up every time the timer interrupt takes place - even when there is no timer to be handled. This behavior is causing a problem of latency for the kvm-rt workload.
The solution to this problem is the integration of the upstream's -rt specific patch .
At the moment of the kvm-rt BZ (BZ1550584) report, I tested  upstream, and it worked fine. However, it depended on the timer wheel rework . And so, I started backporting the timer wheel rework to the kernel-rt.
The timer wheel rework patch set is mostly done now, and it will be ready to be posted soon. However, bugs were found in , making it non-ready for the upstream -rt kernel, so we cannot integrate it in our kernel as well.
So we decided to split the BUG into two bugs:
The enhance BZ backporting the timer wheel rework (this one)
The BUG fix BZ, to integrate the final version of  #BZ1550584
Version-Release number of selected component (if applicable):
RHEL 7.5 kernel
It is still accurate, thanks for the changes, looks better now!
(In reply to Daniel Bristot de Oliveira from comment #11)
> Hi Jaroslav!
> It is still accurate, thanks for the changes, looks better now!
> -- Daniel
Thanks for your verification. By the way, I moved the "." back to the beginning. It is due to AsciiDoc markup, the title must start with a dot.
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.