linux-toradex.git/tools/perf/util/callchain.c, branch v4.10

perf callchain: Reference count maps

2017-02-02T14:39:09+00:00

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: Krister Johansen 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: stable@kernel.org
Fixes: 84c2cafa2889 ("perf tools: Reference count struct map")
Link: http://lkml.kernel.org/r/20170106062331.GB2707@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Introduce callchain_cursor__copy()

2016-12-07T15:00:33+00:00

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: Namhyung Kim 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Minchan Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20161206034010.6499-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Calculate and return the branch flag counting

2016-11-14T16:25:58+00:00

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: Yao Jin 
Acked-by: Andi Kleen 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Linux-kernel@vger.kernel.org
Cc: Yao Jin 
Link: http://lkml.kernel.org/r/1477876794-30749-4-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Add branch flag to callchain cursor node

2016-11-14T16:15:56+00:00

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: Yao Jin 
Acked-by: Andi Kleen 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Linux-kernel@vger.kernel.org
Cc: Yao Jin 
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: Arnaldo Carvalho de Melo

perf callchain: Fixup help/config for no-unwinding

2016-11-08T01:13:47+00:00

Since 841e3558b2d ("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: Rabin Vincent 
Cc: He Kuang 
Fixes: 841e3558b2de ("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.com
Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Move sort__has_parent into struct perf_hpp_list

2016-05-06T00:03:59+00:00

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: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1462276488-26683-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Set callchain_param.enabled when parsing --call-graph

2016-04-18T14:53:07+00:00

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

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Milian Wolff 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-kixllia6r26mz45ng056zq7z@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Start moving away from global per thread cursors

2016-04-14T17:48:07+00:00

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 "", line 1, in 
  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 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-djko3097eyg2rn66v2qcqfvn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Check return value of append_chain_children()

2016-02-19T22:15:01+00:00

Now it can check the error case, so check and pass it to the caller.

Signed-off-by: Namhyung Kim 
Acked-by: Jiri Olsa 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1455631723-17345-7-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Check return value of split_add_child()

2016-02-19T22:14:36+00:00

Now create_child() and add_child() return errors so check and pass it
to the caller.

Signed-off-by: Namhyung Kim 
Acked-by: Jiri Olsa 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1455631723-17345-6-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo