xref: /OK3568_Linux_fs/kernel/Documentation/ABI/testing/sysfs-bus-event_source-devices-format (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunWhat:		/sys/bus/event_source/devices/<dev>/format
2*4882a593SmuzhiyunDate:		January 2012
3*4882a593SmuzhiyunKernelVersion: 3.3
4*4882a593SmuzhiyunContact:	Jiri Olsa <jolsa@redhat.com>
5*4882a593SmuzhiyunDescription:
6*4882a593Smuzhiyun		Attribute group to describe the magic bits that go into
7*4882a593Smuzhiyun		perf_event_attr::config[012] for a particular pmu.
8*4882a593Smuzhiyun		Each attribute of this group defines the 'hardware' bitmask
9*4882a593Smuzhiyun		we want to export, so that userspace can deal with sane
10*4882a593Smuzhiyun		name/value pairs.
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun		Userspace must be prepared for the possibility that attributes
13*4882a593Smuzhiyun		define overlapping bit ranges. For example::
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun			attr1 = 'config:0-23'
16*4882a593Smuzhiyun			attr2 = 'config:0-7'
17*4882a593Smuzhiyun			attr3 = 'config:12-35'
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun		Example: 'config1:1,6-10,44'
20*4882a593Smuzhiyun		Defines contents of attribute that occupies bits 1,6-10,44 of
21*4882a593Smuzhiyun		perf_event_attr::config1.
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