linux-stable/Documentation/ABI/testing/sysfs-bus-event_source-devi...

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What: /sys/devices/cpu/events/
/sys/devices/cpu/events/branch-misses
/sys/devices/cpu/events/cache-references
/sys/devices/cpu/events/cache-misses
/sys/devices/cpu/events/stalled-cycles-frontend
/sys/devices/cpu/events/branch-instructions
/sys/devices/cpu/events/stalled-cycles-backend
/sys/devices/cpu/events/instructions
/sys/devices/cpu/events/cpu-cycles
Date: 2013/01/08
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Generic performance monitoring events
A collection of performance monitoring events that may be
supported by many/most CPUs. These events can be monitored
using the 'perf(1)' tool.
The contents of each file would look like:
event=0xNNNN
where 'N' is a hex digit and the number '0xNNNN' shows the
"raw code" for the perf event identified by the file's
"basename".
What: /sys/bus/event_source/devices/<pmu>/events/<event>
Date: 2014/02/24
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Per-pmu performance monitoring events specific to the running system
Each file (except for some of those with a '.' in them, '.unit'
and '.scale') in the 'events' directory describes a single
performance monitoring event supported by the <pmu>. The name
of the file is the name of the event.
As performance monitoring event names are case
insensitive in the perf tool, the perf tool only looks
for lower or upper case event names in sysfs to avoid
scanning the directory. It is therefore required the
name of the event here is either lower or upper case.
File contents:
<term>[=<value>][,<term>[=<value>]]...
Where <term> is one of the terms listed under
/sys/bus/event_source/devices/<pmu>/format/ and <value> is
a number is base-16 format with a '0x' prefix (lowercase only).
If a <term> is specified alone (without an assigned value), it
is implied that 0x1 is assigned to that <term>.
Examples (each of these lines would be in a separate file):
event=0x2abc
event=0x423,inv,cmask=0x3
domain=0x1,offset=0x8,starting_index=0xffff
domain=0x1,offset=0x8,core=?
Each of the assignments indicates a value to be assigned to a
particular set of bits (as defined by the format file
corresponding to the <term>) in the perf_event structure passed
to the perf_open syscall.
In the case of the last example, a value replacing "?" would
need to be provided by the user selecting the particular event.
This is referred to as "event parameterization". Event
parameters have the format 'param=?'.
What: /sys/bus/event_source/devices/<pmu>/events/<event>.unit
Date: 2014/02/24
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Perf event units
A string specifying the English plural numerical unit that <event>
(once multiplied by <event>.scale) represents.
Example:
Joules
What: /sys/bus/event_source/devices/<pmu>/events/<event>.scale
Date: 2014/02/24
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Perf event scaling factors
A string representing a floating point value expressed in
scientific notation to be multiplied by the event count
received from the kernel to match the unit specified in the
<event>.unit file.
Example:
2.3283064365386962890625e-10
This is provided to avoid performing floating point arithmetic
in the kernel.