Add a field to display the content the raw_data of a synthesized event.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-22-git-send-email-adrian.hunter@intel.com
[ Resolved conflict with 106dacd8 ("perf script: Support -F brstackoff,dso") ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add itrace option to output power events.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-25-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add itrace option to output ptwrite events.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-24-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add byte-swapping macros to kernel.h
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-23-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Instruction trace decoders such as Intel PT may have additional information
recorded in the trace. For example, Intel PT has power information and a
there is a new instruction 'ptwrite' that can write a value into a PTWRITE
trace packet.

Such information may be associated with an IP and so can be treated as a
sample (PERF_RECORD_SAMPLE). Custom data can be incorporated in the
sample as raw_data (PERF_SAMPLE_RAW).

However a means of identifying the raw data format is needed. That will
be done by synthesizing an attribute for it.

So add an attribute type for custom synthesized events.  Different
synthesized events will be identified by the attribute 'config'.

Committer notes:

Start those PERF_TYPE_ after the PMU range, i.e. after (INT_MAX + 1U),
i.e. after perf_pmu_register() -> idr_alloc(end=0).
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1498040239-32418-1-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add ptwrite to the op code map and the perf tools new instructions test.
To run the test:

  $ tools/perf/perf test "x86 ins"
  39: Test x86 instruction decoder - new instructions          : Ok

Or to see the details:

  $ tools/perf/perf test -v "x86 ins" 2>&1 | grep ptwrite

For information about ptwrite, refer the Intel SDM.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Link: http://lkml.kernel.org/r/1495180230-19367-1-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Trivial fix to typo in jvmti_close() warnx warning message.
Signed-off-by: NColin King <colin.king@canonical.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20170627124917.19151-1-colin.king@canonical.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Finally can nuke this function, no more users.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-eivvvzn8ie6w42gy3batxoy7@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Just warn the user and ignore those values.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-tbf60nj3ierm6hrkhpothymx@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To consolidate the error reporting facility.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b41iot1094katoffdf19w9zk@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now everything uses pr_warning(), so ditch it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-hv8r0mgdhk73wtfq3zrhavgx@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Convert sole user of warning() in this file to pr_warning(),
consolidating error reporting facilities.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-3y7yf6v673ujl2rcs34tzv8n@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

warning() is going away, consolidating error reporting.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-5r3636cwl4z1varo90mervai@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Complete the switch to using te pr_{warning,error,etc} error reporting
facilities.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-3l9gr6237b4aqyo0rsspixe2@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

And switch from warning() to pr_warning(), to elliminate another
duplication: too many error reporting facilities.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-pkzcjrhek3uuqc4i5i9ealwd@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The warning(str_error_r(errno)) pattern can be replaced with a function,
do it.

And while at it use pr_warning(), we have way too many error reporting
facilities, time to drop some, starting with the one we got from the git
sources.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-lbak5npj1ri1uuvf1en3c0p0@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This patch adds platform dependency into the test case 15
(perf_event_attr). It is based on a suggestion from Jiri Olsa.

Add a new optional attribute named 'arch' in the [config] section of the
test case file. It is a comma separated list of architecture names this
test can be executed on. For example:

  arch = x86_64,alpha,ppc

If this attribute is missing the test is executed on any platform.  This
does not break existing behavior.

The values listed for this attribute should be identical to uname -m
output.

If the list starts with an exclamation mark (!) the comparison is
inverted, for example for

  arch = !s390x,ppc

the test is not executed on s390x or ppc platforms.  The exclamation
mark must be at the beginnning of the list.

Here is an example debug output:

  [root@s35lp76]# fgrep arch tests/attr/test-stat-C2
  arch = x86_64,alpha,ppc
  [root@s35lp76]# PERF_TEST_ATTR=/tmp /usr/bin/python2 ./tests/attr.py \
    -d ./tests/attr/ -p ./perf -vvvvv -t test-stat-C1

provides the following output:

  running './tests/attr//test-stat-C1'
  test limitation 'x86_64,alpha,ppc' <--- new
    loading expected events
      Event event:base-stat
        fd = 1
        group_fd = -1
        .....

Here is the output when a test is skipped:

  [root@s35lp76]# fgrep arch tests/attr/test-stat-C1
  arch = !s390x
  [root@s35lp76]# PERF_TEST_ATTR=/tmp /usr/bin/python2 ./tests/attr.py \
    -d ./tests/attr/ -p ./perf -vvvvv -t test-stat-C1

provides the following output:

test limitation '!s390x' <--- new

skipped [s390x] './tests/attr//test-stat-C1' <--- new

The test is skipped with return code 0.
Suggested-and-Acked-by: NJiri Olsa <jolsa@redhat.com>
Reviewed-by: NArnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20170622073625.86762-1-tmricht@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-4.13-20170621' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

New features:

 - Add support to measure SMI cost in 'perf stat' (Kan Liang)

 - Add support for unwinding callchains in powerpc with libdw (Paolo Bonzini)

Fixes:

 - Fix message: cpu list option is -C not -c (Adrian Hunter)

 - Fix 'perf script' message: field list option is -F not -f (Adrian Hunter)

 - Intel PT fixes: (Adrian Hunter)

   o Fix missing stack clear
   o Ensure IP is zero when state is INTEL_PT_STATE_NO_IP
   o Fix last_ip usage
   o Ensure never to set 'last_ip' when packet 'count' is zero
   o Clear FUP flag on error
   o Fix transactions_sample_type

Infrastructure changes:

 - Intel PT cleanups/refactorings (Adrian Hunter)

   o Use FUP always when scanning for an IP
   o Add missing __fallthrough
   o Remove redundant initial_skip checks
   o Allow decoding with branch tracing disabled
   o Add default config for pass-through branch enable
   o Add documentation for new config terms
   o Add decoder support for ptwrite and power event packets
   o Add reserved byte to CBR packet payload
   o Add decoder support for CBR events

 - Move  find_process() to the only place that uses it, skimming some
   more fat from util.[ch] (Arnaldo Carvalho de Melo)

 - Do parameter validation earlier on fetch_kernel_version() (Arnaldo Carvalho de Melo)

 - Remove unused _ALL_SOURCE define (Arnaldo Carvalho de Melo)

 - Add sysfs__write_int function (Kan Liang)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Fix message because field list option is -F not -f.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-20-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fix message because cpu list option is -C not -c
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-19-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

'transactions_sample_type' is needed to correctly inject transactions
samples but it was not being set. Set it from the event sample type.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-18-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

'initial_skip' is checked inside the sample synthesis functions which means
it is actually being done twice for 'instructions' and 'transactions'
samples. Remove the redundant checks.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-17-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add decoder support for informing the tools of changes to the core-to-bus
ratio (CBR).
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-16-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Future proof CBR packet decoding by passing through also the undefined
'reserved' byte in the packet payload.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-15-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add decoder support for PTWRITE, MWAIT, PWRE, PWRX and EXSTOP packets. This
patch only affects the decoder, so the tools still do not select or consume
the new information. That is added in subsequent patches.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-14-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add documentation for new config terms.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-13-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Branch tracing is enabled by default, so a fake config bit called 'pt'
(pass-through) was added to allow the 'branch enable' bit to have affect.
Add default config 'pt,branch' which will allow users to disable branch
tracing using 'branch=0' instead of having to specify 'pt,branch=0'.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-12-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The kernel now supports the disabling of branch tracing, however the
decoder assumes branch tracing is always enabled. Pass through a parameter
to indicate whether branch tracing is enabled and use it to avoid cases
when the decoder is expecting branch packets. There are 2 such cases.
First, FUP packets which can bind to an IP even when there is no branch
tracing. Secondly, the decoder will try to use branch packets to find an IP
to start decoding or to recover from errors.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-11-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

perf tools uses __fallthrough. Add missing  __fallthrough to a switch
statement.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-10-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Sometimes a FUP packet is associated with a TSX transaction and a flag is
set to indicate that. Ensure that flag is cleared on any error condition
because at that point the decoder can no longer assume it is correct.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-9-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The decoder will try to use branch packets to find an IP to start decoding
or to recover from errors. Currently the FUP packet is used only in the
case of an overflow, however there is no reason for that to be a special
case. So just use FUP always when scanning for an IP.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-8-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Intel PT uses IP compression based on the last IP. For decoding purposes,
'last IP' is not updated when a branch target has been suppressed, which is
indicated by IPBytes == 0. IPBytes is stored in the packet 'count', so
ensure never to set 'last_ip' when packet 'count' is zero.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-7-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Intel PT uses IP compression based on the last IP. For decoding
purposes, 'last IP' is considered to be reset to zero whenever there is
a synchronization packet (PSB). The decoder wasn't doing that, and was
treating the zero value to mean that there was no last IP, whereas
compression can be done against the zero value. Fix by setting last_ip
to zero when a PSB is received and keep track of have_last_ip.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-6-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

A value of zero is used to indicate that there is no IP. Ensure the
value is zero when the state is INTEL_PT_STATE_NO_IP.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-5-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The return compression stack must be cleared whenever there is a PSB. Fix
one case where that was not happening.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-4-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The decoder uses its current timestamp in samples. Usually that is a
timestamp that has already passed, but in some cases it is a timestamp
for a branch that the decoder is walking towards, and consequently
hasn't reached. Improve that situation by using the pkt_state to
determine when to use the current or previous timestamp.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-3-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Move decoder error setting into one condition.

Cc'ed to stable because later fixes depend on it.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-2-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Porting PPC to libdw only needs an architecture-specific hook to move
the register state from perf to libdw.

The ARM and x86 architectures already use libdw, and it is useful to
have as much common code for the unwinder as possible.  Mark Wielaard
has contributed a frame-based unwinder to libdw, so that unwinding works
even for binaries that do not have CFI information.  In addition,
libunwind is always preferred to libdw by the build machinery so this
cannot introduce regressions on machines that have both libunwind and
libdw installed.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NMilian Wolff <milian.wolff@kdab.com>
Acked-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1496312681-20133-1-git-send-email-pbonzini@redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Implementing a new --smi-cost mode in perf stat to measure SMI cost.

During the measurement, the /sys/device/cpu/freeze_on_smi will be set.

The measurement can be done with one counter (unhalted core cycles), and
two free running MSR counters (IA32_APERF and SMI_COUNT).

In practice, the percentages of SMI core cycles should be more useful
than absolute value. So the output will be the percentage of SMI core
cycles and SMI#. metric_only will be set by default.

SMI cycles% = (aperf - unhalted core cycles) / aperf

Here is an example output.

 Performance counter stats for 'sudo echo ':

SMI cycles%          SMI#
    0.1%              1

       0.010858678 seconds time elapsed

Users who wants to get the actual value can apply additional
--no-metric-only.
Signed-off-by: NKan Liang <Kan.liang@intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1495825538-5230-3-git-send-email-kan.liang@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add sysfs__write_int() to ease up writing int to sysfs.  New interface
is:

  int sysfs__write_int(const char *entry, int value);

Also, introducing filename__write_int() which is useful for new helpers
to write sysctl values.
Signed-off-by: NKan Liang <Kan.liang@intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1495825538-5230-2-git-send-email-kan.liang@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>