From ed90a4466340e51699139ea83dbe0f4536360e6d Mon Sep 17 00:00:00 2001 From: Cody P Schafer Date: Tue, 30 Sep 2014 23:03:19 -0700 Subject: [PATCH] perf Documentation: sysfs events/ interfaces Add documentation for the , .scale, and .unit files in sysfs. .scale and .unit were undocumented. was previously documented only for specific powerpc pmu events. Signed-off-by: Cody P Schafer Signed-off-by: Sukadev Bhattiprolu Cc: Andi Kleen Cc: Anshuman Khandual Cc: Cody P Schafer Cc: Haren Myneni Cc: Haren Myneni Cc: Jiri Olsa Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1412143402-26061-4-git-send-email-sukadev@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- .../sysfs-bus-event_source-devices-events | 60 +++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events index 7b40a3cbc26a..a5226f094159 100644 --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events @@ -599,3 +599,63 @@ 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//format file. + +What: /sys/bus/event_source/devices//events/ +Date: 2014/02/24 +Contact: Linux kernel mailing list +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 . The name + of the file is the name of the event. + + File contents: + + [=][,[=]]... + + Where is one of the terms listed under + /sys/bus/event_source/devices//format/ and is + a number is base-16 format with a '0x' prefix (lowercase only). + If a is specified alone (without an assigned value), it + is implied that 0x1 is assigned to that . + + 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 ) in the perf_event structure passed + to the perf_open syscall. + +What: /sys/bus/event_source/devices//events/.unit +Date: 2014/02/24 +Contact: Linux kernel mailing list +Description: Perf event units + + A string specifying the English plural numerical unit that + (once multiplied by .scale) represents. + + Example: + + Joules + +What: /sys/bus/event_source/devices//events/.scale +Date: 2014/02/24 +Contact: Linux kernel mailing list +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 + .unit file. + + Example: + + 2.3283064365386962890625e-10 + + This is provided to avoid performing floating point arithmetic + in the kernel. -- 2.20.1