| What: /sys/bus/event_source/devices/<dev>/format |
| Date: January 2012 |
| KernelVersion: 3.3 |
| Contact: Jiri Olsa <jolsa@redhat.com> |
| Description: |
| Attribute group to describe the magic bits that go into |
| perf_event_attr::config[012] for a particular pmu. |
| Each attribute of this group defines the 'hardware' bitmask |
| we want to export, so that userspace can deal with sane |
| name/value pairs. |
| |
| Userspace must be prepared for the possibility that attributes |
| define overlapping bit ranges. For example: |
| attr1 = 'config:0-23' |
| attr2 = 'config:0-7' |
| attr3 = 'config:12-35' |
| |
| Example: 'config1:1,6-10,44' |
| Defines contents of attribute that occupies bits 1,6-10,44 of |
| perf_event_attr::config1. |
