On Fri, Jul 08, 2022 at 11:23:45AM +0000, Sebastian Ene wrote:
> This driver creates per-cpu hrtimers which are required to do the
> periodic 'pet' operation. On a conventional watchdog-core driver, the
> userspace is responsible for delivering the 'pet' events by writing to
> the particular /dev/watchdogN node. In this case we require a strong
> thread affinity to be able to account for lost time on a per vCPU.
>
> This part of the driver is the 'frontend' which is reponsible for
> delivering the periodic 'pet' events, configuring the virtual peripheral
> and listening for cpu hotplug events. The other part of the driver is
> an emulated MMIO device which is part of the KVM virtual machine
> monitor and this part accounts for lost time by looking at the
> /proc/{}/task/{}/stat entries.
>
> Reviewed-by: Will Deacon <will@xxxxxxxxxx>
> Signed-off-by: Sebastian Ene <sebastianene@xxxxxxxxxx>
> ---
> drivers/misc/Kconfig | 14 ++
> drivers/misc/Makefile | 1 +
> drivers/misc/vcpu_stall_detector.c | 223 +++++++++++++++++++++++++++++
> 3 files changed, 238 insertions(+)
> create mode 100644 drivers/misc/vcpu_stall_detector.c
>
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index 41d2bb0ae23a..d5b7610459f7 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -483,6 +483,20 @@ config OPEN_DICE
>
> If unsure, say N.
>
> +config VCPU_STALL_DETECTOR
> + tristate "Guest vCPU stall detector"
> + select LOCKUP_DETECTOR
This should be a "depends on", not a select, right? This got enabled on
my build when I didn't want it to, and trying to track down why it was
enabled would be a pain for people.
thanks,
greg k-h
