06f45fe96f
Add syfs nodes for each xenbus device showing event statistics (number of events and spurious events, number of associated event channels) and for setting a spurious event threshold in case a frontend is sending too many events without being rogue on purpose. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210219154030.10892-7-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
1.6 KiB
What: /sys/devices/*/xenbus/event_channels Date: February 2021 Contact: Xen Developers mailing list xen-devel@lists.xenproject.org Description: Number of Xen event channels associated with a kernel based paravirtualized device frontend or backend.
What: /sys/devices/*/xenbus/events Date: February 2021 Contact: Xen Developers mailing list xen-devel@lists.xenproject.org Description: Total number of Xen events received for a Xen pv device frontend or backend.
What: /sys/devices/*/xenbus/jiffies_eoi_delayed Date: February 2021 Contact: Xen Developers mailing list xen-devel@lists.xenproject.org Description: Summed up time in jiffies the EOI of an interrupt for a Xen pv device has been delayed in order to avoid stalls due to event storms. This value rising is a first sign for a rogue other end of the pv device.
What: /sys/devices/*/xenbus/spurious_events Date: February 2021 Contact: Xen Developers mailing list xen-devel@lists.xenproject.org Description: Number of events received for a Xen pv device which did not require any action. Too many spurious events in a row will trigger delayed EOI processing.
What: /sys/devices/*/xenbus/spurious_threshold Date: February 2021 Contact: Xen Developers mailing list xen-devel@lists.xenproject.org Description: Controls the tolerated number of subsequent spurious events before delayed EOI processing is triggered for a Xen pv device. Default is 1. This can be modified in case the other end of the pv device is issuing spurious events on a regular basis and is known not to be malicious on purpose. Raising the value for such cases can improve pv device performance.