Add documentation for the <event>, <event>.scale, and <event>.unit files in sysfs. <event>.scale and <event>.unit were undocumented. <event> was previously documented only for specific powerpc pmu events. I've added a restriction that event names cannot contain '.' characters so we can avoid breaking the API when we (inevitably) add more 'event.????' files. Signed-off-by: Cody P Schafer <cody@xxxxxxxxxxxxxxxxxx> --- .../testing/sysfs-bus-event_source-devices-events | 59 ++++++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events index 3c1cc24..5393e1ed6 100644 --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events @@ -82,3 +82,62 @@ Description: POWER-systems specific performance monitoring events Further, multiple terms like 'event=0xNNNN' can be specified and separated with comma. All available terms are defined in the /sys/bus/event_source/devices/<dev>/format file. + +What: /sys/bus/event_source/devices/<pmu>/events/<event> +Date: 2014/02/24 +Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx> +Description: Per-pmu performance monitoring events specific to the running system + + Each file (with a name not containing a '.') 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. + + 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 seperate file): + + event=0x2abc + event=0x423,inv,cmask=0x3 + domain=0x1,offset=0x8,starting_index=0xffff + + 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. + +What: /sys/bus/event_source/devices/<pmu>/events/<event>.unit +Date: 2014/02/24 +Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx> +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@xxxxxxxxxxxxxxx> +Description: Perf event scaling factors + + A string representing a floating point value expressed in + scientific notation to be multiplied by the event count + recieved 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. -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
