linux/tools
Adrian Hunter bc9b6bf07c perf tools: Add Intel PT support for PSB periods
The PSB packet is a synchronization packet that provides a starting
point for decoding or recovery from errors.

This patch adds support for a new Intel PT feature that allows the
frequency of PSB packets to be specified.

Support for this feature is indicated by
/sys/bus/event_source/devices/intel_pt/caps/psb_cyc which contains "1"
if the feature is supported and "0" otherwise.

The PSB period can be specified as a PMU config term e.g. perf record -e
intel_pt/psb_period=2/u sleep 1

The default value is 3 or the nearest lower value that is supported.  0
is always supported.

Valid values are given by:

/sys/bus/event_source/devices/intel_pt/caps/psb_periods

which contains a hexadecimal value, the bits of which represent valid
values e.g. bit 2 set means value 2 is valid.

The value is converted to the approximate number of trace bytes between
PSB packets as:

	2 ^ (value + 11)

e.g. value 3 means 16KiB bytes between PSBs

If an invalid value is entered, the error message will give a list of
valid values e.g.

	$ perf record -e intel_pt/psb_period=15/u uname
	Invalid psb_period for intel_pt. Valid values are: 0-5

tools/perf/Documentation/intel-pt.txt is updated in a later patch as
there are a number of new features being added.

For more information about PSB periods refer to the Intel 64 and IA-32
Architectures SDM Chapter 36 Intel Processor Trace from June 2015 or
later.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-18-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-24 17:45:08 -03:00
..
arch tools include: Add basic atomic.h implementation from the kernel sources 2015-05-08 16:11:05 -03:00
build perf tools: Add Intel PT instruction decoder 2015-08-17 11:11:36 -03:00
cgroup
firewire
hv Drivers: hv: fcopy: full handshake support 2015-05-24 12:17:42 -07:00
iio tools:iio:iio_utils: pass strings as const 2015-06-01 08:40:26 +01:00
include tools: Copy rbtree_augmented.h from the kernel 2015-07-05 22:59:05 -03:00
laptop/freefall Move freefall program from Documentation/ to tools/ 2015-06-08 16:42:07 -06:00
lguest
lib tools lib traceevent: Add checks for returned EVENT_ERROR type 2015-08-21 10:35:09 -03:00
net tools: bpf_jit_disasm: fix segfault on disabled debugging log output 2015-05-27 00:24:10 -04:00
nfsd
perf perf tools: Add Intel PT support for PSB periods 2015-08-24 17:45:08 -03:00
power Additional ACPICA material for v4.2-rc1 2015-07-02 17:11:28 -07:00
scripts
testing linux-kselftest-4.2-rc5 2015-07-28 10:09:53 -07:00
thermal/tmon tools/thermal: tmon: fixed the 'make install' command 2015-05-09 13:36:58 +08:00
time
usb
virtio
vm tools: Fix tools/vm build 2015-05-12 18:11:06 -03:00
Makefile Staging driver patches for 4.2-rc1 2015-06-26 15:46:08 -07:00