Besides memory allocation failure, tips.txt may fail to load because the
file is not found (a more likely cause).

Communicate that to the user in tips failure warning.
Signed-off-by: NDavid Carrillo-Cisneros <davidcc@google.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170412064919.92449-5-davidcc@google.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

(This is a patch has been sitting in the Intel CQM/CMT driver series for
 a while, despite not depend on it. Sending it now independently since
 the series is being discarded.)

When an event is in error state, read() returns 0 instead of sizeof()
buffer. In certain modes, such as interval printing, ignoring the 0
return value may cause bogus count deltas to be computed and thus
invalid results printed.

This patch fixes this problem by modifying read_counters() to mark the
event as not scaled (scaled = -1) to force the printout routine to show
<NOT COUNTED>.
Signed-off-by: NStephane Eranian <eranian@google.com>
Reviewed-by: NDavid Carrillo-Cisneros <davidcc@google.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170412182301.44406-1-davidcc@google.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When parsing disassemble lines for source line number, use a stripped
line instead of raw line.
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1491612748-1605-3-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When parsing disassemble lines, use ltrim() and rtrim() to strip them,
not using just while loop and isspace().
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1491612748-1605-2-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Pipe-mode has no perf.data header, hence no upfront knowledge of presend
and missing features, hence, do not print missing features in pipe-mode.
Signed-off-by: NDavid Carrillo-Cisneros <davidcc@google.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170410201432.24807-8-davidcc@google.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Session sets a number parameters that rely on evlist. These parameters
are not used in pipe-mode and should not be set, since evlist is
unavailable. Fix that.
Signed-off-by: NDavid Carrillo-Cisneros <davidcc@google.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170410201432.24807-6-davidcc@google.com
[ Check if file != NULL in perf_session__new(), like when used by builtin-top.c ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

__perf_session__process_pipe_events reuses the same memory buffer to
process all events in the pipe.

When reordering is needed (e.g. -b option), events are not immediately
flushed, but kept around until reordering is possible, causing
memory corruption.

The problem is usually observed by a "Unknown sample error" output. It
can easily be reproduced by:

  perf record -o - noploop | perf inject -b > output

Committer testing:

Before:

  $ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null
  stress: info: [8297] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd
  stress: info: [8297] successful run completed in 2s
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]
  Warning:
  Found 1 unknown events!

  Is this an older tool processing a perf.data file generated by a more recent tool?

  If that is not the case, consider reporting to linux-kernel@vger.kernel.org.

  $

After:

  $ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null
  stress: info: [9027] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd
  stress: info: [9027] successful run completed in 2s
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]
  no symbols found in /usr/bin/stress, maybe install a debug package?
  no symbols found in /usr/bin/stress, maybe install a debug package?
  $
Signed-off-by: NDavid Carrillo-Cisneros <davidcc@google.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170410201432.24807-3-davidcc@google.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Implement simple detection for all kind of jumps and branches.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Cc: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: stable@kernel.org # v4.10+
Link: http://lkml.kernel.org/r/1491465112-45819-3-git-send-email-borntraeger@de.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

since 4.10 perf annotate exits on s390 with an "unknown error -95".
Turns out that commit 786c1b51 ("perf annotate: Start supporting
cross arch annotation") added a hard requirement for architecture
support when objdump is used but only provided x86 and arm support.
Meanwhile power was added so lets add s390 as well.

While at it make sure to implement the branch and jump types.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Cc: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: stable@kernel.org # v4.10+
Fixes: 786c1b51 "perf annotate: Start supporting cross arch annotation"
Link: http://lkml.kernel.org/r/1491465112-45819-2-git-send-email-borntraeger@de.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We don't need to use strlen(), a var, or check for the end explicitely,
isspace('\0') is false:

  [acme@jouet c]$ cat ltrim.c
  #include <ctype.h>
  #include <stdio.h>

  static char *ltrim(char *s)
  {
	  while (isspace(*s))
		  ++s;
	  return s;
  }

  int main(void)
  {
	  printf("ltrim(\"\")='%s'\n", ltrim(""));
	  return 0;
  }
  [acme@jouet c]$ ./ltrim
  ltrim("")=''
  [acme@jouet c]$

Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/n/tip-w3nk0x3pai2vojk2ab6kdvaw@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

After reading command name from /proc/<pid>/status, use ltrim() and
rtrim() to strip command name, not using just while loop, isspace() and
etc.
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1491575061-704-6-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1491575061-704-5-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The kernel has a special check for a specific irq_vectors trace event.

TRACE_EVENT_PERF_PERM(irq_work_exit,
	is_sampling_event(p_event) ? -EPERM : 0);

The perf-record fails for this irq_vectors event when it is present,
like when using a wildcard:

  root@skl:/tmp# perf record -a -e irq_vectors:* sleep 2
  Error:
  You may not have permission to collect system-wide stats.

  Consider tweaking /proc/sys/kernel/perf_event_paranoid,
  which controls use of the performance events system by
  unprivileged users (without CAP_SYS_ADMIN).

  The current value is 2:

    -1: Allow use of (almost) all events by all users
  >= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
  >= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
  >= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN

  To make this setting permanent, edit /etc/sysctl.conf too, e.g.:

        kernel.perf_event_paranoid = -1

This patch prints out the exact sub event that failed with EPERM for
wildcards to help in understanding what went wrong when this event is
present:

After the patch:

  root@skl:/tmp# perf record -a -e irq_vectors:* sleep 2
  Error:
  No permission to enable irq_vectors:irq_work_exit event.

  You may not have permission to collect system-wide stats.
  ......

Committer notes:

So we have a lot of irq_vectors events:

  [root@jouet ~]# perf list irq_vectors:*

  List of pre-defined events (to be used in -e):

    irq_vectors:call_function_entry                    [Tracepoint event]
    irq_vectors:call_function_exit                     [Tracepoint event]
    irq_vectors:call_function_single_entry             [Tracepoint event]
    irq_vectors:call_function_single_exit              [Tracepoint event]
    irq_vectors:deferred_error_apic_entry              [Tracepoint event]
    irq_vectors:deferred_error_apic_exit               [Tracepoint event]
    irq_vectors:error_apic_entry                       [Tracepoint event]
    irq_vectors:error_apic_exit                        [Tracepoint event]
    irq_vectors:irq_work_entry                         [Tracepoint event]
    irq_vectors:irq_work_exit                          [Tracepoint event]
    irq_vectors:local_timer_entry                      [Tracepoint event]
    irq_vectors:local_timer_exit                       [Tracepoint event]
    irq_vectors:reschedule_entry                       [Tracepoint event]
    irq_vectors:reschedule_exit                        [Tracepoint event]
    irq_vectors:spurious_apic_entry                    [Tracepoint event]
    irq_vectors:spurious_apic_exit                     [Tracepoint event]
    irq_vectors:thermal_apic_entry                     [Tracepoint event]
    irq_vectors:thermal_apic_exit                      [Tracepoint event]
    irq_vectors:threshold_apic_entry                   [Tracepoint event]
    irq_vectors:threshold_apic_exit                    [Tracepoint event]
    irq_vectors:x86_platform_ipi_entry                 [Tracepoint event]
    irq_vectors:x86_platform_ipi_exit                  [Tracepoint event]
  #

And some may be sampled:

  [root@jouet ~]# perf record -e irq_vectors:local* sleep 20s
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.020 MB perf.data (2 samples) ]
  [root@jouet ~]# perf report -D | egrep 'stats:|events:'
  Aggregated stats:
             TOTAL events:        155
              MMAP events:        144
              COMM events:          2
              EXIT events:          1
            SAMPLE events:          2
             MMAP2 events:          4
    FINISHED_ROUND events:          1
         TIME_CONV events:          1
  irq_vectors:local_timer_entry stats:
             TOTAL events:          1
            SAMPLE events:          1
  irq_vectors:local_timer_exit stats:
             TOTAL events:          1
            SAMPLE events:          1
  [root@jouet ~]#

But, as shown in the tracepoint definition at the start of this message,
some, like "irq_vectors:irq_work_exit", may not be sampled, just counted,
i.e. if we try to sample, as when using 'perf record', we get an error:

  [root@jouet ~]# perf record -e irq_vectors:irq_work_exit
  Error:
  You may not have permission to collect system-wide stats.

  Consider tweaking /proc/sys/kernel/perf_event_paranoid,
<SNIP>

The error message is misleading, this patch will help in pointing out
what is the event causing such an error, but the error message needs
improvement, i.e. we need to figure out a way to check if a tracepoint
is counting only, like this one, when all we can do is to count it with
'perf stat', at most printing the delta using interval printing, as in:

   [root@jouet ~]# perf stat -I 5000 -e irq_vectors:irq_work_*
  #           time             counts unit events
       5.000168871                  0      irq_vectors:irq_work_entry
       5.000168871                  0      irq_vectors:irq_work_exit
      10.000676730                  0      irq_vectors:irq_work_entry
      10.000676730                  0      irq_vectors:irq_work_exit
      15.001122415                  0      irq_vectors:irq_work_entry
      15.001122415                  0      irq_vectors:irq_work_exit
      20.001298051                  0      irq_vectors:irq_work_entry
      20.001298051                  0      irq_vectors:irq_work_exit
      25.001485020                  1      irq_vectors:irq_work_entry
      25.001485020                  1      irq_vectors:irq_work_exit
      30.001658706                  0      irq_vectors:irq_work_entry
      30.001658706                  0      irq_vectors:irq_work_exit
  ^C    32.045711878                  0      irq_vectors:irq_work_entry
      32.045711878                  0      irq_vectors:irq_work_exit

  [root@jouet ~]#

But at least, when we use a wildcard, this patch helps a bit.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1491566932-503-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Trying to keep everything reentrant.

Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-rdce0p2k9e1b4qnrb8ki9mtf@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

since 4.10 perf annotate exits on s390 with an "unknown error -95".
Turns out that commit 786c1b51 ("perf annotate: Start supporting
cross arch annotation") added a hard requirement for architecture
support when objdump is used but only provided x86 and arm support.
Meanwhile power was added so lets add s390 as well.

While at it make sure to implement the branch and jump types.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Cc: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: stable@kernel.org # v4.10+
Fixes: 786c1b51 "perf annotate: Start supporting cross arch annotation"
Link: http://lkml.kernel.org/r/1491465112-45819-2-git-send-email-borntraeger@de.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The option 'show-total-period' works fine without a option '-l'.  But if
running 'perf annotate --stdio -l --show-total-period', you can see a
problem showing only zero '0' for number of samples.

Before:
    $ perf annotate --stdio -l --show-total-period
...
       0 :        400816:       push   %rbp
       0 :        400817:       mov    %rsp,%rbp
       0 :        40081a:       mov    %edi,-0x24(%rbp)
       0 :        40081d:       mov    %rsi,-0x30(%rbp)
       0 :        400821:       mov    -0x24(%rbp),%eax
       0 :        400824:       mov    -0x30(%rbp),%rdx
       0 :        400828:       mov    (%rdx),%esi
       0 :        40082a:       mov    $0x0,%edx
...

The reason is it was missed to set number of samples of
source_line_samples, so set it ordinarily.

After:
    $ perf annotate --stdio -l --show-total-period
...
       3 :        400816:       push   %rbp
       4 :        400817:       mov    %rsp,%rbp
       0 :        40081a:       mov    %edi,-0x24(%rbp)
       0 :        40081d:       mov    %rsi,-0x30(%rbp)
       1 :        400821:       mov    -0x24(%rbp),%eax
       2 :        400824:       mov    -0x30(%rbp),%rdx
       0 :        400828:       mov    (%rdx),%esi
       1 :        40082a:       mov    $0x0,%edx
...
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin Liska <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 0c4a5bce ("perf annotate: Display total number of samples with --show-total-period")
Link: http://lkml.kernel.org/r/1490703125-13643-1-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Trying to remove die() calls from library functions, postponing exiting
to the tool main code.

Link: http://lkml.kernel.org/n/tip-ackxq5nqe39gunln3tkczs42@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The callers of perf_read_values__enlarge_counters() already propagate
errors, so just print some debug diagnostics and handle allocation
failures gracefully, not trying to do silly things like 'a =
realloc(a)'.

Link: http://lkml.kernel.org/n/tip-nsmmh7uzpg35rzcl9nq7yztp@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently we fail in the following case:

  $ unset HOME
  $ ./perf record ls
  $ echo $?
  255

It's because the config code init fails due to a missing HOME variable
value. Fix this by skipping the user config init if there's no HOME
variable value.
Reported-by: NJan Stancek <jstancek@redhat.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170330144637.7468-1-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Trivial fix to spelling mistake in pr_debug message.
Signed-off-by: NColin King <colin.king@canonical.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20170330095440.19444-1-colin.king@canonical.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

For some platforms, for example Broadwell, it doesn't support cycles
for LBR. But the perf always prints cycles:0, it's not necessary.

The patch refactors the LBR info print code and drops the cycles:0.

For example: perf report --branch-history --no-children --stdio

On Broadwell:
--0.91%--__random_r random_r.c:394 (iterations:2)
          __random_r random_r.c:360 (predicted:0.0%)
          __random_r random_r.c:380 (predicted:0.0%)
          __random_r random_r.c:357

On Skylake:
--1.07%--main div.c:39 (predicted:52.4% cycles:1 iterations:17)
          main div.c:44 (predicted:52.4% cycles:1)
          main div.c:42 (cycles:2)
          compute_flag div.c:28 (cycles:2)
          compute_flag div.c:27 (cycles:1)
          rand rand.c:28 (cycles:1)
          rand rand.c:28 (cycles:1)
          __random random.c:298 (cycles:1)
          __random random.c:297 (cycles:1)
          __random random.c:295 (cycles:1)
          __random random.c:295 (cycles:1)
          __random random.c:295 (cycles:1)
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1489046786-10061-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

SDT marker argument is in N@OP format. N is the size of argument and OP
is the actual assembly operand. OP is arch dependent component and hence
it's parsing logic also should be placed under tools/perf/arch/.
Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170328094754.3156-3-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This came from 'git', but isn't documented anywhere in
tools/perf/Documentation/, looks like baggage we can do without, 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-e7uwkn60t4hmlnwj99ba4t2s@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Simplification: it is easier to open /proc/self/exe than /proc/$pid/exe.
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-7-tommi.t.rantala@nokia.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Ensure that the string that we read from the data file is null terminated.

Valgrind was complaining:

  ==31357== Invalid read of size 1
  ==31357==    at 0x4EC8C1: __strtok_r_1c (string2.h:200)
  ==31357==    by 0x4EC8C1: parse_ftrace_printk (trace-event-parse.c:161)
  ==31357==    by 0x4F82A8: read_ftrace_printk (trace-event-read.c:204)
  ==31357==    by 0x4F82A8: trace_report (trace-event-read.c:468)
  ==31357==    by 0x4CD552: process_tracing_data (header.c:1576)
  ==31357==    by 0x4D3397: perf_file_section__process (header.c:2705)
  ==31357==    by 0x4D3397: perf_header__process_sections (header.c:2488)
  ==31357==    by 0x4D3397: perf_session__read_header (header.c:2925)
  ==31357==    by 0x4E71E2: perf_session__open (session.c:32)
  ==31357==    by 0x4E71E2: perf_session__new (session.c:139)
  ==31357==    by 0x429F5D: cmd_annotate (builtin-annotate.c:472)
  ==31357==    by 0x497150: run_builtin (perf.c:359)
  ==31357==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==31357==    by 0x428CE0: run_argv (perf.c:467)
  ==31357==    by 0x428CE0: main (perf.c:614)
  ==31357==  Address 0x8ac0efb is 0 bytes after a block of size 1,963 alloc'd
  ==31357==    at 0x4C2DB9D: malloc (vg_replace_malloc.c:299)
  ==31357==    by 0x4F827B: read_ftrace_printk (trace-event-read.c:195)
  ==31357==    by 0x4F827B: trace_report (trace-event-read.c:468)
  ==31357==    by 0x4CD552: process_tracing_data (header.c:1576)
  ==31357==    by 0x4D3397: perf_file_section__process (header.c:2705)
  ==31357==    by 0x4D3397: perf_header__process_sections (header.c:2488)
  ==31357==    by 0x4D3397: perf_session__read_header (header.c:2925)
  ==31357==    by 0x4E71E2: perf_session__open (session.c:32)
  ==31357==    by 0x4E71E2: perf_session__new (session.c:139)
  ==31357==    by 0x429F5D: cmd_annotate (builtin-annotate.c:472)
  ==31357==    by 0x497150: run_builtin (perf.c:359)
  ==31357==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==31357==    by 0x428CE0: run_argv (perf.c:467)
  ==31357==    by 0x428CE0: main (perf.c:614)
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-6-tommi.t.rantala@nokia.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Ensure that we have space for the null byte in buf.
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-5-tommi.t.rantala@nokia.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Valgrind was complaining:

  $ valgrind ./perf list >/dev/null
  ==11643== Memcheck, a memory error detector
  ==11643== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
  ==11643== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
  ==11643== Command: ./perf list
  ==11643==
  ==11643== Conditional jump or move depends on uninitialised value(s)
  ==11643==    at 0x4C30620: rindex (vg_replace_strmem.c:199)
  ==11643==    by 0x49DAA9: build_id_cache__origname (build-id.c:198)
  ==11643==    by 0x49E1C7: build_id_cache__valid_id (build-id.c:222)
  ==11643==    by 0x49E1C7: build_id_cache__list_all (build-id.c:507)
  ==11643==    by 0x4B9C8F: print_sdt_events (parse-events.c:2067)
  ==11643==    by 0x4BB0B3: print_events (parse-events.c:2313)
  ==11643==    by 0x439501: cmd_list (builtin-list.c:53)
  ==11643==    by 0x497150: run_builtin (perf.c:359)
  ==11643==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==11643==    by 0x428CE0: run_argv (perf.c:467)
  ==11643==    by 0x428CE0: main (perf.c:614)
  [...]

Additionally, a zero length result from readlink() is not very interesting.
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-3-tommi.t.rantala@nokia.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Valgrind was complaining:

  ==2633== Syscall param open(filename) points to unaddressable byte(s)
  ==2633==    at 0x5281CC0: __open_nocancel (syscall-template.S:84)
  ==2633==    by 0x537D38: open (fcntl2.h:53)
  ==2633==    by 0x537D38: get_sdt_note_list (symbol-elf.c:2017)
  ==2633==    by 0x5396FD: probe_cache__scan_sdt (probe-file.c:700)
  ==2633==    by 0x49EA2C: build_id_cache__add_sdt_cache (build-id.c:625)
  ==2633==    by 0x49EA2C: build_id_cache__add_s (build-id.c:697)
  ==2633==    by 0x49EE72: build_id_cache__add_b (build-id.c:717)
  ==2633==    by 0x49EE72: dso__cache_build_id (build-id.c:782)
  ==2633==    by 0x49F190: __dsos__cache_build_ids (build-id.c:793)
  ==2633==    by 0x49F190: machine__cache_build_ids (build-id.c:801)
  ==2633==    by 0x49F190: perf_session__cache_build_ids (build-id.c:815)
  ==2633==    by 0x4CD4F2: write_build_id (header.c:165)
  ==2633==    by 0x4D26F7: do_write_feat (header.c:2296)
  ==2633==    by 0x4D26F7: perf_header__adds_write (header.c:2335)
  ==2633==    by 0x4D26F7: perf_session__write_header (header.c:2414)
  ==2633==    by 0x43B324: __cmd_record (builtin-record.c:1154)
  ==2633==    by 0x43B324: cmd_record (builtin-record.c:1839)
  ==2633==    by 0x455A07: __cmd_record (builtin-kmem.c:1868)
  ==2633==    by 0x455A07: cmd_kmem (builtin-kmem.c:1944)
  ==2633==    by 0x497150: run_builtin (perf.c:359)
  ==2633==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==2633==    by 0x428CE0: run_argv (perf.c:467)
  ==2633==    by 0x428CE0: main (perf.c:614)
  ==2633==  Address 0x0 is not stack'd, malloc'd or (recently) free'd
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tommi Rantala <tommi.t.rantala@nokia.com>
Link: http://lkml.kernel.org/r/20170322130624.21881-2-tommi.t.rantala@nokia.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently perf-annotate with --print-line can print
-nan(0x8000000000000) because of division by zero when calculating
percent. The division by zero happens when a sum of samples is zero in
symbol__get_source_line(), so fix it.

For example:

After running 'perf record' like below,

    $ perf record -e "{cycles,page-faults,branch-misses}" ./a.out

Before:

    $ perf annotate --stdio -l

  Sorted summary for file /home/taeung/workspace/a.out
  ----------------------------------------------

   32.89    -nan    7.04 a.c:38
   25.14    -nan    0.00 a.c:34
   16.26    -nan   56.34 a.c:31
   15.88    -nan    1.41 a.c:37
    5.67    -nan    0.00 a.c:39
    1.13    -nan   35.21 a.c:26
    0.95    -nan    0.00 a.c:44
    0.57    -nan    0.00 a.c:32
   Percent                 |      Source code & Disassembly of a.out for cycles (529 samples)
  -----------------------------------------------------------------------------------------
                         :
  ...

   a.c:26    0.57    -nan    4.23 :         40081a:       mov    %edi,-0x24(%rbp)
   a.c:26    0.00    -nan    9.86 :         40081d:       mov    %rsi,-0x30(%rbp)

  ...

However, if a sum of samples is zero (e.g. 'page-faults'),
skip calculating percent.

After:

    $ perf annotate --stdio -l

  Sorted summary for file /home/taeung/workspace/a.out
  ----------------------------------------------

   32.89    0.00    7.04 a.c:38
   25.14    0.00    0.00 a.c:34
   16.26    0.00   56.34 a.c:31
   15.88    0.00    1.41 a.c:37
    5.67    0.00    0.00 a.c:39
    1.13    0.00   35.21 a.c:26
    0.95    0.00    0.00 a.c:44
    0.57    0.00    0.00 a.c:32
   Percent                 |      Source code & Disassembly of old for cycles (529 samples)
  -----------------------------------------------------------------------------------------
                         :
  ...

  a.c:26    0.57    0.00    4.23 :         40081a:       mov    %edi,-0x24(%rbp)
  a.c:26    0.00    0.00    9.86 :         40081d:       mov    %rsi,-0x30(%rbp)

  ...
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1490598638-13947-3-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It is wrong way to read link name from a build-id file.  Because a
build-id file is not anymore a symbolic link but build-id directory of
it is symbolic link, so fix it.

For example, if build-id file name gotten from
dso__build_id_filename() is as below,

  /root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1/elf

To correctly read link name of build-id, use the build-id dir path that
is a symbolic link, instead of the above build-id file name like below.

  /root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1490598638-13947-2-git-send-email-treeze.taeung@gmail.com
Fixes: 01412261 ("perf buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid")
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Often it is interesting to know how costly a given source line is in
total. Previously, one had to build these sums manually based on all
addresses that pointed to the same source line. This patch introduces
srcline as a sort key, which will do the aggregation for us.

Paired with the recent addition of showing inline frames, this makes
perf report much more useful for many C++ work loads.

The following shows the new feature in action. First, let's show the
status quo output when we sort by address. The result contains many hist
entries that generate the same output:

  ~~~~~~~~~~~~~~~~
  $ perf report --stdio --inline -g address
  # Children      Self  Command       Shared Object        Symbol
  # ........  ........  ............  ...................  .........................................
  #
      99.89%    35.34%  cpp-inlining  cpp-inlining         [.] main
            |
            |--64.55%--main complex:655
            |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
            |          /usr/include/c++/6.3.1/complex:664 (inline)
            |          |
            |          |--60.31%--hypot +20
            |          |          |
            |          |          |--8.52%--__hypot_finite +273
            |          |          |
            |          |          |--7.32%--__hypot_finite +411
...
             --35.34%--_start +4194346
                       __libc_start_main +241
                       |
                       |--6.65%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
                       |
                       |--2.70%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
                       |
                       |--1.69%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
  ...
  ~~~~~~~~~~~~~~~~

With this patch and `-g srcline` we instead get the following output:

  ~~~~~~~~~~~~~~~~
  $ perf report --stdio --inline -g srcline
  # Children      Self  Command       Shared Object        Symbol
  # ........  ........  ............  ...................  .........................................
  #
      99.89%    35.34%  cpp-inlining  cpp-inlining         [.] main
            |
            |--64.55%--main complex:655
            |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
            |          /usr/include/c++/6.3.1/complex:664 (inline)
            |          |
            |          |--64.02%--hypot
            |          |          |
            |          |           --59.81%--__hypot_finite
            |          |
            |           --0.53%--cabs
            |
             --35.34%--_start
                       __libc_start_main
                       |
                       |--12.48%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
  ...
  ~~~~~~~~~~~~~~~~
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170318214928.9047-1-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If the address belongs to an inlined function, the source information
back to the first non-inlined function will be printed.

For example:

1. Show inlined function name
   perf report -g function --inline

-    0.69%     0.00%  inline   ld-2.23.so           [.] dl_main
   - dl_main
        0.56% _dl_relocate_object
         _dl_relocate_object (inline)
         elf_dynamic_do_Rela (inline)

2. Show the file/line information
   perf report -g address --inline

-    0.69%     0.00%  inline   ld-2.23.so           [.] _dl_start
     _dl_start rtld.c:307
      /build/glibc-GKVZIf/glibc-2.23/elf/rtld.c:413 (inline)
   + _dl_sysdep_start dl-sysdep.c:250
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-6-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It takes some time to look for inline stack for callgraph addresses.  So
it provides new option "--inline" to let user decide if enable this
feature.

  --inline:

  If a callgraph address belongs to an inlined function, the inline stack
  will be printed. Each entry is the inline function name or file/line.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Tested-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-4-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It would be useful for perf to support a mode to query the inline stack
for a given callgraph address. This would simplify finding the right
code in code that does a lot of inlining.

The srcline.c has contained the code which supports to translate the
address to filename:line_nr. This patch just extends the function to let
it support getting the inline stacks.

It introduces the inline_list which will store the inline function
result (filename:line_nr and funcname).

If BFD lib is not supported, the result is only filename:line_nr.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Tested-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-3-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Introduce dso__name() and filename_split() out of existing code because
these codes will be used in several places in next patch.

For filename_split(), it may also solve a potential memory leak in
existing code. In existing addr2line(),

        sep = strchr(filename, ':');
        if (sep) {
                *sep++ = '\0';
                *file = filename;
                *line_nr = strtoul(sep, NULL, 0);
                ret = 1;
        }

out:
        pclose(fp);
        return ret;

If sep is NULL, filename is not freed or returned via file.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Tested-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-2-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Address filtering with kernel symbols incorrectly resulted in the error
"Cannot determine size of symbol" because the no_size logic was the wrong
way around.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NAndi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org # v4.9+
Link: http://lkml.kernel.org/r/1490357752-27942-1-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Move the printing of perf expressions and internal events to a new
clearer --details flag, instead of lumping it together with other debug
options in --debug. This makes it clearer to use.

Before

  perf list --debug
  ...
  unc_m_power_critical_throttle_cycles
         [Cycles all ranks are in critical thermal throttle. Unit: uncore_imc]
          uncore_imc_2/event=0x86/  MetricName: power_critical_throttle_cycles % MetricExpr: (unc_m_power_critical_throttle_cycles / unc_m_clockticks) * 100.

after

  perf list --details
  ...
  unc_m_power_critical_throttle_cycles
         [Cycles all ranks are in critical thermal throttle. Unit: uncore_imc]
          uncore_imc_2/event=0x86/  MetricName: power_critical_throttle_cycles % MetricExpr: (unc_m_power_critical_throttle_cycles / unc_m_clockticks) * 100.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/20170320201711.14142-14-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add support for a new JSON event attribute to name MetricExpr for better
output in perf stat.

If the event has no MetricName it uses the normal event name instead to
describe the metric.

Before

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
           time unc_p_freq_max_os_cycles
     1.000149775     15.7
     2.000344807     19.3
     3.000502544     16.7
     4.000640656      6.6
     5.000779955      9.9

After

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
           time freq_max_os_cycles %
     1.000149775     15.7
     2.000344807     19.3
     3.000502544     16.7
     4.000640656      6.6
     5.000779955      9.9
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-13-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Output the metric expr in perf list when --debug is specified, so that
the user can check the formula.

Before:

  % perf list
    ...
    unc_m_power_channel_ppd
         [Cycles where DRAM ranks are in power down (CKE) mode. Derived from unc_m_power_channel_ppd. Unit:
          uncore_imc]
          uncore_imc_2/event=0x85/

After:

  % perf list --debug
    ...
    unc_m_power_channel_ppd
         [Cycles where DRAM ranks are in power down (CKE) mode. Derived from unc_m_power_channel_ppd. Unit:
          uncore_imc]
          Perf: uncore_imc_2/event=0x85/ MetricExpr: (unc_m_power_channel_ppd / unc_m_clockticks) * 100.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-12-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add generic infrastructure to perf stat to output ratios for
"MetricExpr" entries in the event lists. Many events are more useful as
ratios than in raw form, typically some count in relation to total
ticks.

Transfer the MetricExpr information from the alias to the evsel.

We mark the events that need to be collected for MetricExpr, and also
link the events using them with a pointer. The code is careful to always
prefer the right event in the same group to minimize multiplexing
errors. At the moment only a single relation is supported.

Then add a rblist to the stat shadow code that remembers stats based on
the cpu and context.

Then finally update and retrieve and print these values similarly to the
existing hardcoded perf metrics. We use the simple expression parser
added earlier to evaluate the expression.

Normally we just output the result without further commentary, but for
--metric-only this would lead to empty columns. So for this case use the
original event as description.

There is no attempt to automatically add the MetricExpr event, if it is
missing, however we suggest it to the user, because the user tool
doesn't have enough information to reliably construct a group that is
guaranteed to schedule. So we leave that to the user.

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}'
       1.000147889        800,085,181      unc_p_clockticks
       1.000147889         93,126,241      unc_p_freq_max_os_cycles  #     11.6
       2.000448381        800,218,217      unc_p_clockticks
       2.000448381        142,516,095      unc_p_freq_max_os_cycles  #     17.8
       3.000639852        800,243,057      unc_p_clockticks
       3.000639852        162,292,689      unc_p_freq_max_os_cycles  #     20.3

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
  #    time         freq_max_os_cycles %
       1.000127077      0.9
       2.000301436      0.7
       3.000456379      0.0

v2: Change from DivideBy to MetricExpr
v3: Use expr__ prefix.  Support more than one other event.
v4: Update description
v5: Only print warning message once for multiple PMUs.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-11-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>