The original patch that introduced inline frame output in the various
browsers used this suffix already. The new centralized approach that
uses fake symbols for inlined frames was missing this approach so far.

Instead of changing the symbol name itself, we only print the suffix
where needed. This allows us to efficiently lookup the symbol for a
given name without first having to append the suffix before the lookup.
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Reviewed-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20171009203310.17362-8-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When a callchain entry has no srcline available, we ended up comparing
the instruction pointer. I consider this to be not too useful. Rather, I
think we should group the entries by function name, which this patch
adds. For people who want to split the data on the IP boundary, using
`-g address` is the correct choice.

Before:

~~~~~
   100.00%    38.86%  [.] main
            |
            |--61.14%--main inlining.cpp:14
            |          std::norm<double> complex:664
            |          std::_Norm_helper<true>::_S_do_it<double> complex:654
            |          std::abs<double> complex:597
            |          std::__complex_abs complex:589
            |          |
            |          |--56.03%--hypot
            |          |          |
            |          |          |--8.45%--__hypot_finite
            |          |          |
            |          |          |--7.62%--__hypot_finite
            |          |          |
            |          |          |--2.29%--__hypot_finite
            |          |          |
            |          |          |--2.24%--__hypot_finite
            |          |          |
            |          |          |--2.06%--__hypot_finite
            |          |          |
            |          |          |--1.81%--__hypot_finite
...
~~~~~

After:

~~~~~
   100.00%    38.86%  [.] main
            |
            |--61.14%--main inlining.cpp:14
            |          std::norm<double> complex:664
            |          std::_Norm_helper<true>::_S_do_it<double> complex:654
            |          std::abs<double> complex:597
            |          std::__complex_abs complex:589
            |          |
            |          |--60.29%--hypot
            |          |          |
            |          |           --56.03%--__hypot_finite
            |          |
            |           --0.85%--cabs
~~~~~
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Reviewed-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20171009203310.17362-7-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is mostly a preparation to enable the creation of full callchain
nodes for inline frames. Such frames will reference the IP of the
non-inlined frame, but hold the symbol and srcline for an inlined
location. As such, we won't be able to query the srcline on-demand based
on the IP alone. Instead, we will leverage the functionality provided by
this patch here, and store the srcline for the inlined nodes in the new
srcline member of callchain_cursor_node.

Note that this patch on its own leaks the srcline, as there is no
free_callchain_cursor_node or similar. A future patch will add caching
of the srcline and handle deletion properly.
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Reviewed-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20171009203310.17362-3-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Two functions from different binaries can have same start address. Thus,
comparing only start address in match_chain() leads to inconsistent
callchains. Fix this by adding a check for dsos as well.

Ex, https://www.spinics.net/lists/linux-perf-users/msg04067.htmlReported-by: NAlexander Pozdneev <pozdneyev@gmail.com>
Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: zhangmengting@huawei.com
Link: http://lkml.kernel.org/r/20171005091234.5874-1-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With --call-graph option, perf report can display call chains using
type, min percent threshold, optional print limit and order. And the
default call-graph parameter is 'graph,0.5,caller,function,percent'.

Before this patch, 'perf report --call-graph' shows incorrect debug
messages as below:

  # perf report --call-graph
  Invalid callchain mode: 0.5
  Invalid callchain order: 0.5
  Invalid callchain sort key: 0.5
  Invalid callchain config key: 0.5
  Invalid callchain mode: caller
  Invalid callchain mode: function
  Invalid callchain order: function
  Invalid callchain mode: percent
  Invalid callchain order: percent
  Invalid callchain sort key: percent

That is because in function __parse_callchain_report_opt(),each field of
the call-graph parameter is passed to parse_callchain_{mode,order,
sort_key,value} in turn until it meets the matching value.

For example, the order field "caller" is passed to
parse_callchain_mode() firstly and obviously it doesn't match any mode
field. Therefore parse_callchain_mode() will shows the debug message
"Invalid callchain mode: caller", which could confuse users.

The patch fixes this issue by moving the warning out of the function
parse_callchain_{mode,order,sort_key,value}.
Signed-off-by: NMengting Zhang <zhangmengting@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
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: Krister Johansen <kjlx@templeofstupid.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1506154694-39691-1-git-send-email-zhangmengting@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The branch history code has a loop detection function. With this, we can
get the number of iterations by calculating the removed loops.

While it would be nice for knowing the average cycles of iterations.
This patch adds up the cycles in branch entries of removed loops and
save the result to the next branch entry (e.g. branch entry A).

Finally it will display the iteration number and average cycles at the
"from" of branch entry A.

For example:
perf record -g -j any,save_type ./div
perf report --branch-history --no-children --stdio

--22.63%--main div.c:42 (RET CROSS_2M)
          compute_flag div.c:28 (cycles:2 iter:173115 avg_cycles:2)
          |
           --10.73%--compute_flag div.c:27 (RET CROSS_2M)
                     rand rand.c:28 (cycles:1)
                     rand rand.c:28 (RET CROSS_2M)
                     __random random.c:298 (cycles:1)
                     __random random.c:297 (COND_BWD CROSS_2M)
                     __random random.c:295 (cycles:1)
                     __random random.c:295 (COND_BWD CROSS_2M)
                     __random random.c:295 (cycles:1)
                     __random random.c:295 (RET CROSS_2M)
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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/1502111115-18305-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Current --branch-history LBR annotation displays confused data. For
example, each cycles report is duplicated on both "from" and "to"
entries.

For example:

  perf report --branch-history --no-children --stdio

  --2.32%--main div.c:39 (COND_BWD CROSS_2M predicted:49.7% cycles:1)
            main div.c:44 (predicted:49.7% cycles:1)
            main div.c:42 (RET CROSS_2M cycles:2)
            compute_flag div.c:28 (cycles:2)
            compute_flag div.c:27 (RET CROSS_2M cycles:1)
            rand rand.c:28 (cycles:1)
            rand rand.c:28 (RET CROSS_2M cycles:1)
            __random random.c:298 (cycles:1)
            __random random.c:297 (COND_BWD CROSS_2M cycles:1)
            __random random.c:295 (cycles:1)
            __random random.c:295 (COND_BWD CROSS_2M cycles:1)
            __random random.c:295 (cycles:1)
            __random random.c:295 (RET CROSS_2M cycles:9)

The cycles should be tagged only on the "from". It's for the code block
that ends with "from", not for "to".

Another issue is the "predicted:49.7%" is duplicated too (tag on both
"from" and "to").

This patch tags the branch type/flag on "to" and tag the cycles on
"from".

For example:

  --2.32%--main div.c:39 (COND_BWD CROSS_2M predicted:49.7%)
            main div.c:44 (cycles:1)
            main div.c:42 (RET CROSS_2M)
            compute_flag div.c:28 (cycles:2)
            compute_flag div.c:27 (RET CROSS_2M)
            rand rand.c:28 (cycles:1)
            rand rand.c:28 (RET CROSS_2M)
            __random random.c:298 (cycles:1)
            __random random.c:297 (COND_BWD CROSS_2M)
            __random random.c:295 (cycles:1)
            __random random.c:295 (COND_BWD CROSS_2M)
            __random random.c:295 (cycles:1)
            __random random.c:295 (RET CROSS_2M)
            |
             --2.23%--__random_r random_r.c:392 (cycles:9)

In this example, The "main div.c:39 (COND_BWD CROSS_2M predicted:49.7%)"
is "to" of branch and "main div.c:44 (cycles:1)" is "from" of branch.
It should be easier for understanding than before.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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/1500894547-18411-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

  perf record -b -g <command>
  perf report --branch-history

This merges the LBRs with the callgraphs.

However it would be nice if it also works without callgraphs (-g) set in
perf record, so that only the LBRs are displayed.  But currently perf
report errors in this case. For example,

  perf record -b <command>
  perf report --branch-history

  Error:
  Selected -g or --branch-history but no callchain data. Did
  you call 'perf record' without -g?

This patch displays the LBRs only even if callgraphs(-g) is not enabled
in perf record.

Change log:

v2: According to Milian Wolff's comment, change the obsolete error
message. Now the error message is:

                 ┌─Error:─────────────────────────────────────┐
                 │Selected -g or --branch-history.            │
                 │But no callchain or branch data.            │
                 │Did you call 'perf record' without -g or -b?│
                 │                                            │
                 │                                            │
                 │Press any key...                            │
                 └────────────────────────────────────────────┘

When passing the last parameter to hists__fprintf,
changes "|" to "||".

  hists__fprintf(hists, !quiet, 0, 0, rep->min_percent, stdout,
                 symbol_conf.use_callchain || symbol_conf.show_branchflag_count);
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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/1494240182-28899-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Replacing prefixcmp(), same purpose, inverted result, so standardize on
the kernel variant, to reduce silly differences among tools/ and the
kernel sources, making it easier for people to work in both codebases.

And then doing:

	if (strstarts(option, "no-"))

Looks clearer than doing:

	if (!prefixcmp(option, "no-"))

To figure out if option starts witn "no-".

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-kaei42gi7lpa8subwtv7eug8@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Show branch type in callchain entry. The branch type is printed
with other LBR information (such as cycles/abort/...).

For example:

  perf record -g -j any,save_type
  perf report --branch-history --stdio --no-children

  38.50%  div.c:45                [.] main                    div
          |
          ---main div.c:42 (RET CROSS_2M cycles:2)
             compute_flag div.c:28 (cycles:2)
             compute_flag div.c:27 (RET CROSS_2M cycles:1)
             rand rand.c:28 (cycles:1)
             rand rand.c:28 (RET CROSS_2M cycles:1)
             __random random.c:298 (cycles:1)
             __random random.c:297 (COND_BWD CROSS_2M cycles:1)
             __random random.c:295 (cycles:1)
             __random random.c:295 (COND_BWD CROSS_2M cycles:1)
             __random random.c:295 (cycles:1)
             __random random.c:295 (RET CROSS_2M cycles:9)

Change log

v6: Remove the branch_type_str() since it's moved to branch.c.

v5: Rewrite the branch info print code in util/callchain.c.

v4: Comparing to previous version, the major changes are:
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1500379995-6449-8-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The branch info such as predicted/cycles/... are printed at the
callchain entries.

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

    --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)

But the current code is difficult to maintain and extend. This patch
refactors the code for easy maintenance.

Change log:

v6: 1. Put the multiline condition code into {} brackets in
       counts_str_build()

    2. Keep the original display order, that is:
       predicted, abort, cycles, iterations

v5: It's a new patch in v5 patch series.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1500379995-6449-5-git-send-email-yao.jin@linux.intel.com
[ Don't use 'index' as a name for a variable, it shadows a globa decl in older distros ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

I just hit a segfault when doing `perf report -g srcline`.
Valgrind pointed me at this code as the culprit:

  ==8359== Invalid read of size 8
  ==8359==    at 0x3096D9: map__rip_2objdump (map.c:430)
  ==8359==    by 0x2FC1A3: match_chain_srcline (callchain.c:645)
  ==8359==    by 0x2FC1A3: match_chain (callchain.c:700)
  ==8359==    by 0x2FC1A3: append_chain (callchain.c:895)
  ==8359==    by 0x2FC1A3: append_chain_children (callchain.c:846)
  ==8359==    by 0x2FF719: callchain_append (callchain.c:944)
  ==8359==    by 0x2FF719: hist_entry__append_callchain (callchain.c:1058)
  ==8359==    by 0x32FA06: iter_add_single_cumulative_entry (hist.c:908)
  ==8359==    by 0x33195C: hist_entry_iter__add (hist.c:1050)
  ==8359==    by 0x258F65: process_sample_event (builtin-report.c:204)
  ==8359==    by 0x30D60C: perf_session__deliver_event (session.c:1310)
  ==8359==    by 0x30D60C: ordered_events__deliver_event (session.c:119)
  ==8359==    by 0x310D12: __ordered_events__flush (ordered-events.c:210)
  ==8359==    by 0x310D12: ordered_events__flush.part.3 (ordered-events.c:277)
  ==8359==    by 0x30DD3C: perf_session__process_user_event (session.c:1349)
  ==8359==    by 0x30DD3C: perf_session__process_event (session.c:1475)
  ==8359==    by 0x30FC3C: __perf_session__process_events (session.c:1867)
  ==8359==    by 0x30FC3C: perf_session__process_events (session.c:1921)
  ==8359==    by 0x25A985: __cmd_report (builtin-report.c:575)
  ==8359==    by 0x25A985: cmd_report (builtin-report.c:1054)
  ==8359==    by 0x2B9A80: run_builtin (perf.c:296)
  ==8359==  Address 0x70 is not stack'd, malloc'd or (recently) free'd

This patch fixes the issue.
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
[ Remove dependency from another change ]
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-2-namhyung@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Where they belong, no point in leaving those in the generic "util"
files.

Link: http://lkml.kernel.org/n/tip-ljx3iiip1hlfa7a7apjem7ph@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Needed to use the PRI[xu](32,64) formatting macros.

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-wkbho8kaw24q67dd11q0j39f@git.kernel.orgSigned-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>

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>

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 dso__load_kcore frees all of the existing maps, but one has already
been attached to a callchain cursor node, then we can get a SIGSEGV in
any function that happens to try to use this invalid cursor.  Use the
existing map refcount mechanism to forestall cleanup of a map until the
cursor iterates past the node.
Signed-off-by: NKrister Johansen <kjlx@templeofstupid.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@kernel.org
Fixes: 84c2cafa ("perf tools: Reference count struct map")
Link: http://lkml.kernel.org/r/20170106062331.GB2707@templeofstupid.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If dso__load_kcore frees all of the existing maps, but one has already
been attached to a callchain cursor node, then we can get a SIGSEGV in
any function that happens to try to use this invalid cursor.  Use the
existing map refcount mechanism to forestall cleanup of a map until the
cursor iterates past the node.
Signed-off-by: NKrister Johansen <kjlx@templeofstupid.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@kernel.org
Fixes: 84c2cafa ("perf tools: Reference count struct map")
Link: http://lkml.kernel.org/r/20170106062331.GB2707@templeofstupid.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Previously these were being ignored, sometimes silently.

Stop doing that, emitting debug messages and handling the errors.

Testing it:

  $ cat ~/.perfconfig
  cat: /home/acme/.perfconfig: No such file or directory
  $ perf stat -e cycles usleep 1

   Performance counter stats for 'usleep 1':

           938,996      cycles:u

       0.003813731 seconds time elapsed

  $ perf top --stdio
  Error:
  You may not have permission to collect system-wide stats.

  Consider tweaking /proc/sys/kernel/perf_event_paranoid,
  <SNIP>
  [ perf record: Captured and wrote 0.019 MB perf.data (7 samples) ]
  [acme@jouet linux]$ perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  # Overhead  Command  Shared Object      Symbol
  # ........  .......  .................  .........................
    71.77%  usleep   libc-2.24.so       [.] _dl_addr
    27.07%  usleep   ld-2.24.so         [.] _dl_next_ld_env_entry
     1.13%  usleep   [kernel.kallsyms]  [k] page_fault
  $
  $ touch ~/.perfconfig
  $ ls -la ~/.perfconfig
  -rw-rw-r--. 1 acme acme 0 Jan 27 12:14 /home/acme/.perfconfig
  $
  $ perf stat -e instructions usleep 1

   Performance counter stats for 'usleep 1':

           244,610      instructions:u

       0.000805383 seconds time elapsed

  $
  [root@jouet ~]# chown acme.acme ~/.perfconfig
  [root@jouet ~]# perf stat -e cycles usleep 1
    Warning: File /root/.perfconfig not owned by current user or root, ignoring it.

   Performance counter stats for 'usleep 1':

           937,615      cycles

       0.000836931 seconds time elapsed
  #

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-j2rq96so6xdqlr8p8rd6a3jx@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The callchain_cursor__copy() function is to save current callchain
captured by a cursor.  It'll be used to keep callchains when switching
to idle task for each cpu.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161206034010.6499-3-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Create some branch counters in per callchain list entry. Each counter
is for a branch flag. For example, predicted_count counts all the
*predicted* branches. The counters get updated by processing the
callchain cursor nodes.

It also provides functions to retrieve or print the values of counters
in callchain list.

Besides the counting for branch flags, it also counts and returns the
average number of iterations.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Acked-by: NAndi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1477876794-30749-4-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Since the branch ip has been added to call stack for easier browsing,
this patch adds more branch information. For example, add a flag to
indicate if this ip is a branch, and also add with the branch flag.

Then we can know if the cursor node represents a branch and know what
the branch flag it has.

The branch history code has a loop detection pass that removes loops. It
would be nice for knowing how many loops were removed then in next
steps, we can compute out the average number of iterations.

For example:

Before remove_loops(),
entry0: from = 0x100, to = 0x200
entry1: from = 0x300, to = 0x250
entry2: from = 0x300, to = 0x250
entry3: from = 0x300, to = 0x250
entry4: from = 0x700, to = 0x800

After remove_loops()
entry0: from = 0x100, to = 0x200
entry1: from = 0x300, to = 0x250
entry2: from = 0x700, to = 0x800

The original entry2 and entry3 are removed. So the number of iterations
(from = 0x300, to = 0x250) is equal to removed number + 1 (2 + 1).

iterations = removed number + 1;
average iteractions = Sum(iteractions) / number of samples

This formula ignores other cases, for example, iterations cross multiple
buffers and one buffer contains 2+ loops. Because in practice, it's good
enough.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Acked-by: NAndi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/n/1477876794-30749-2-git-send-email-yao.jin@linux.intel.com
[ Renamed 'iter' to 'nr_loop_iter' for clarity ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Since 841e3558 ("perf callchain: Recording 'dwarf' callchains do not
need DWARF unwinding support"), --call-graph dwarf is allowed in 'perf
record' even without unwind support.  A couple of other places don't
reflect this yet though: the help text should list dwarf as a valid
record mode and the dump_size config should be respected too.
Signed-off-by: NRabin Vincent <rabinv@axis.com>
Cc: He Kuang <hekuang@huawei.com>
Fixes: 841e3558 ("perf callchain: Recording 'dwarf' callchains do not need DWARF unwinding support")
Link: http://lkml.kernel.org/r/1470837148-7642-1-git-send-email-rabin.vincent@axis.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_parent into struct perf_hpp_list.
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/1462276488-26683-3-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Trying to move in the direction of using callchain_param for all
callchain parameters, eventually ditching them from symbol_conf.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-kixllia6r26mz45ng056zq7z@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The recent perf_evsel__fprintf_callchain() move to evsel.c added several
new symbol requirements to the python binding, for instance:

  # perf test -v python
  16: Try 'import perf' in python, checking link problems      :
  --- start ---
  test child forked, pid 18030
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  ImportError: /tmp/build/perf/python/perf.so: undefined symbol:
  callchain_cursor
  test child finished with -1
  ---- end ----
  Try 'import perf' in python, checking link problems: FAILED!
  #

This would require linking against callchain.c to access to the global
callchain_cursor variables.

Since lots of functions already receive as a parameter a
callchain_cursor struct pointer, make that be the case for some more
function so that we can start phasing out usage of yet another global
variable.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@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-djko3097eyg2rn66v2qcqfvn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now it can check the error case, so check and pass it to the caller.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1455631723-17345-7-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now create_child() and add_child() return errors so check and pass it
to the caller.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1455631723-17345-6-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The append_chain() might return either result of match_chain() or other
(error) code.  But match_chain() can return any value in s64 type so
it's hard to check the error case.  Add new enum match_result and make
match_chain() return non-negative values only so that we can check the
error cases.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1455631723-17345-5-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Memory allocation in the fill_node() can fail so change its return type
to int and check it in add_child() too.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1455631723-17345-4-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The create_child() in add_child() can return NULL in case of memory
allocation failure.  So check the return value and bail out.  The proper
error handling will be added later.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1455631723-17345-3-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It missed to decay periods in callchains when decaying hist entries.
This resulted in more than 100 percent overhead in callchains in the
fractal style output.
Reported-by: NArnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1451963160-17196-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The callchain rbtree is rebuilt periodically, so it needs to
reinitialize the root everytime.  Otherwise it can be stuck in the
rbtree insertion with stale pointers.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1448521700-32062-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The flat callchain mode is to print all chains in a single, simple
hierarchy so make it easy to see.

Currently perf report --tui doesn't show flat callchains properly.  With
flat callchains, only leaf nodes are added to the final rbtree so it
should show entries in parent nodes.  To do that, add parent_val list to
struct callchain_node and show them along with the (normal) val list.

For example, consider following callchains with '-g graph'.

  $ perf report -g graph
  - 39.93%  swapper  [kernel.vmlinux]  [k] intel_idle
       intel_idle
       cpuidle_enter_state
       cpuidle_enter
       call_cpuidle
     - cpu_startup_entry
          28.63% start_secondary
        - 11.30% rest_init
             start_kernel
             x86_64_start_reservations
             x86_64_start_kernel

Before:
  $ perf report -g flat
  - 39.93%  swapper  [kernel.vmlinux]  [k] intel_idle
       28.63% start_secondary
     - 11.30% rest_init
          start_kernel
          x86_64_start_reservations
          x86_64_start_kernel

After:
  $ perf report -g flat
  - 39.93%  swapper  [kernel.vmlinux]  [k] intel_idle
     - 28.63% intel_idle
          cpuidle_enter_state
          cpuidle_enter
          call_cpuidle
          cpu_startup_entry
          start_secondary
     - 11.30% intel_idle
          cpuidle_enter_state
          cpuidle_enter
          call_cpuidle
          cpu_startup_entry
          start_kernel
          x86_64_start_reservations
          x86_64_start_kernel
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NBrendan Gregg <brendan.d.gregg@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1447047946-1691-8-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now -g/--call-graph option supports how to display callchain values.
Possible values are 'percent', 'period' and 'count'.  The percent is
same as before and it's the default behavior.  The period displays the
raw period value rather than the percentage.  The count displays the
number of occurrences.

  $ perf report --no-children --stdio -g percent
  ...
    39.93%  swapper  [kernel.vmlinux]  [k] intel_idel
            |
            ---intel_idle
               cpuidle_enter_state
               cpuidle_enter
               call_cpuidle
               cpu_startup_entry
               |
               |--28.63%-- start_secondary
               |
                --11.30%-- rest_init

  $ perf report --no-children --show-total-period --stdio -g period
  ...
    39.93%   13018705  swapper  [kernel.vmlinux]  [k] intel_idel
            |
            ---intel_idle
               cpuidle_enter_state
               cpuidle_enter
               call_cpuidle
               cpu_startup_entry
               |
               |--9334403-- start_secondary
               |
                --3684302-- rest_init

  $ perf report --no-children --show-nr-samples --stdio -g count
  ...
    39.93%     80  swapper  [kernel.vmlinux]  [k] intel_idel
            |
            ---intel_idle
               cpuidle_enter_state
               cpuidle_enter
               call_cpuidle
               cpu_startup_entry
               |
               |--57-- start_secondary
               |
                --23-- rest_init
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NBrendan Gregg <brendan.d.gregg@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1447047946-1691-6-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It's to track the count of occurrences of the callchains.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NBrendan Gregg <brendan.d.gregg@gmail.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1447047946-1691-5-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is a preparation to support for printing other type of callchain
value like count or period.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NBrendan Gregg <brendan.d.gregg@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1447047946-1691-4-git-send-email-namhyung@kernel.org
[ renamed new _sprintf_ operation to _scnprintf_ ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add new call chain option (-g) 'folded' to print callchains in a line.
The callchains are separated by semicolons, and preceded by (absolute)
percent values and a space.

For example, the following 20 lines can be printed in 3 lines with the
folded output mode:

  $ perf report -g flat --no-children | grep -v ^# | head -20
      60.48%  swapper  [kernel.vmlinux]  [k] intel_idle
              54.60%
                 intel_idle
                 cpuidle_enter_state
                 cpuidle_enter
                 call_cpuidle
                 cpu_startup_entry
                 start_secondary

              5.88%
                 intel_idle
                 cpuidle_enter_state
                 cpuidle_enter
                 call_cpuidle
                 cpu_startup_entry
                 rest_init
                 start_kernel
                 x86_64_start_reservations
                 x86_64_start_kernel

  $ perf report -g folded --no-children | grep -v ^# | head -3
      60.48%  swapper  [kernel.vmlinux]  [k] intel_idle
  54.60% intel_idle;cpuidle_enter_state;cpuidle_enter;call_cpuidle;cpu_startup_entry;start_secondary
  5.88% intel_idle;cpuidle_enter_state;cpuidle_enter;call_cpuidle;cpu_startup_entry;rest_init;start_kernel;x86_64_start_reservations;x86_64_start_kernel

This mode is supported only for --stdio now and intended to be used by
some scripts like in FlameGraphs[1].  Support for other UI might be
added later.

[1] http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.htmlRequested-and-Tested-by: NBrendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1447047946-1691-2-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The caller callchain order is useful with --children option since it can
show 'overview' style output, but other commands which don't use
--children feature like 'perf script' or even 'perf report/top' without
--children are better to keep callee order.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NBrendan Gregg <brendan.d.gregg@gmail.com>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1445499946-29817-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>