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  1. 20 2月, 2016 5 次提交
  3. 08 1月, 2016 1 次提交
  5. 27 11月, 2015 1 次提交
  7. 20 11月, 2015 5 次提交
  9. 23 10月, 2015 2 次提交
  11. 09 8月, 2015 1 次提交
  13. 06 8月, 2015 1 次提交
  15. 19 2月, 2015 1 次提交
    • K
      perf tools: Enable LBR call stack support · aad2b21c
      由 Kan Liang 提交于 
      Currently, there are two call chain recording options, fp and dwarf.

Haswell has a new feature that utilizes the existing LBR facility to
record call chains. Kernel side LBR support code provides this as a
third option to record call chains. This patch enables the lbr call
stack support on the tooling side.

LBR call stack has some limitations:

 - It reuses current LBR facility, so LBR call stack and branch record
   can not be enabled at the same time.

 - It is only available for user-space callchains.

However, it also offers some advantages:

 - LBR call stack can work on user apps which don't have frame-pointers
   or dwarf debug info compiled. It is a good alternative when nothing
   else works.
Tested-by: NJiri Olsa <jolsa@kernel.org>
Signed-off-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Jacob Shin <jacob.w.shin@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1420482185-29830-2-git-send-email-kan.liang@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      aad2b21c
  17. 08 1月, 2015 1 次提交
  19. 09 12月, 2014 1 次提交
  21. 02 12月, 2014 1 次提交
    • A
      perf callchain: Support handling complete branch stacks as histograms · 8b7bad58
      由 Andi Kleen 提交于 
      Currently branch stacks can be only shown as edge histograms for
individual branches. I never found this display particularly useful.

This implements an alternative mode that creates histograms over
complete branch traces, instead of individual branches, similar to how
normal callgraphs are handled. This is done by putting it in front of
the normal callgraph and then using the normal callgraph histogram
infrastructure to unify them.

This way in complex functions we can understand the control flow that
lead to a particular sample, and may even see some control flow in the
caller for short functions.

Example (simplified, of course for such simple code this is usually not
needed), please run this after the whole patchkit is in, as at this
point in the patch order there is no --branch-history, that will be
added in a patch after this one:

tcall.c:

volatile a = 10000, b = 100000, c;

__attribute__((noinline)) f2()
{
	c = a / b;
}

__attribute__((noinline)) f1()
{
	f2();
	f2();
}
main()
{
	int i;
	for (i = 0; i < 1000000; i++)
		f1();
}

% perf record -b -g ./tsrc/tcall
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.044 MB perf.data (~1923 samples) ]
% perf report --no-children --branch-history
...
    54.91%  tcall.c:6  [.] f2                      tcall
            |
            |--65.53%-- f2 tcall.c:5
            |          |
            |          |--70.83%-- f1 tcall.c:11
            |          |          f1 tcall.c:10
            |          |          main tcall.c:18
            |          |          main tcall.c:18
            |          |          main tcall.c:17
            |          |          main tcall.c:17
            |          |          f1 tcall.c:13
            |          |          f1 tcall.c:13
            |          |          f2 tcall.c:7
            |          |          f2 tcall.c:5
            |          |          f1 tcall.c:12
            |          |          f1 tcall.c:12
            |          |          f2 tcall.c:7
            |          |          f2 tcall.c:5
            |          |          f1 tcall.c:11
            |          |
            |           --29.17%-- f1 tcall.c:12
            |                     f1 tcall.c:12
            |                     f2 tcall.c:7
            |                     f2 tcall.c:5
            |                     f1 tcall.c:11
            |                     f1 tcall.c:10
            |                     main tcall.c:18
            |                     main tcall.c:18
            |                     main tcall.c:17
            |                     main tcall.c:17
            |                     f1 tcall.c:13
            |                     f1 tcall.c:13
            |                     f2 tcall.c:7
            |                     f2 tcall.c:5
            |                     f1 tcall.c:12

The default output is unchanged.

This is only implemented in perf report, no change to record or anywhere
else.

This adds the basic code to report:

- add a new "branch" option to the -g option parser to enable this mode
- when the flag is set include the LBR into the callstack in machine.c.

The rest of the history code is unchanged and doesn't know the
difference between LBR entry and normal call entry.

- detect overlaps with the callchain
- remove small loop duplicates in the LBR

Current limitations:

- The LBR flags (mispredict etc.) are not shown in the history
and LBR entries have no special marker.
- It would be nice if annotate marked the LBR entries somehow
(e.g. with arrows)

v2: Various fixes.
v3: Merge further patches into this one. Fix white space.
v4: Improve manpage. Address review feedback.
v5: Rename functions. Better error message without -g. Fix crash without
    -b.
v6: Rebase
v7: Rebase. Use NO_ENTRY in memset.
v8: Port to latest tip. Move add_callchain_ip to separate
    patch. Skip initial entries in callchain. Minor cleanups.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1415844328-4884-3-git-send-email-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      8b7bad58
  23. 25 11月, 2014 2 次提交
  25. 19 11月, 2014 1 次提交
  27. 29 10月, 2014 1 次提交
  29. 26 9月, 2014 2 次提交
  31. 15 8月, 2014 1 次提交
    • N
      perf report: Relax -g option parsing not to limit the option order · e8232f1a
      由 Namhyung Kim 提交于 
      Current perf report -g/--call-graph option parser requires for option
argument having following order:

  type,min_percent[,print_limit],order,key

But sometimes it's annoying to type all even if one just wants to change
the "order" or "key" setting.

This patch fixes it to remove the ordering restriction so that one can
use just "-g caller", for instance.  The only remaining restriction is
that the "print_limit" always comes after the "min_percent".
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Link: http://lkml.kernel.org/r/1407996100-6359-2-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e8232f1a
  33. 17 7月, 2014 1 次提交
  35. 01 6月, 2014 2 次提交
  37. 22 4月, 2014 1 次提交
  39. 17 1月, 2014 2 次提交
  41. 16 1月, 2014 1 次提交
  43. 22 10月, 2013 1 次提交
    • N
      perf callchain: Convert children list to rbtree · e369517c
      由 Namhyung Kim 提交于 
      Current collapse stage has a scalability problem which can be reproduced
easily with a parallel kernel build.

This is because it needs to traverse every children of callchains
linearly during the collapse/merge stage.

Converting it to a rbtree reduced the overhead significantly.

On my 400MB perf.data file which recorded with make -j32 kernel build:

  $ time perf --no-pager report --stdio > /dev/null

before:
  real	6m22.073s
  user	6m18.683s
  sys	0m0.706s

after:
  real	0m20.780s
  user	0m19.962s
  sys	0m0.689s

During the perf report the overhead on append_chain_children went down
from 96.69% to 18.16%:

  -  18.16%  perf  perf                [.] append_chain_children
     - append_chain_children
        - 77.48% append_chain_children
           + 69.79% merge_chain_branch
           - 22.96% append_chain_children
              + 67.44% merge_chain_branch
              + 30.15% append_chain_children
              + 2.41% callchain_append
           + 7.25% callchain_append
        + 12.26% callchain_append
        + 10.22% merge_chain_branch
  +  11.58%  perf  perf                [.] dso__find_symbol
  +   8.02%  perf  perf                [.] sort__comm_cmp
  +   5.48%  perf  libc-2.17.so        [.] malloc_consolidate
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1381468543-25334-2-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e369517c
  45. 30 8月, 2013 1 次提交
  47. 22 7月, 2013 1 次提交
  49. 07 2月, 2013 1 次提交
  51. 11 9月, 2012 1 次提交
    • I
      perf tools: Use __maybe_used for unused variables · 1d037ca1
      由 Irina Tirdea 提交于 
      perf defines both __used and __unused variables to use for marking
unused variables. The variable __used is defined to
__attribute__((__unused__)), which contradicts the kernel definition to
__attribute__((__used__)) for new gcc versions. On Android, __used is
also defined in system headers and this leads to warnings like: warning:
'__used__' attribute ignored

__unused is not defined in the kernel and is not a standard definition.
If __unused is included everywhere instead of __used, this leads to
conflicts with glibc headers, since glibc has a variables with this name
in its headers.

The best approach is to use __maybe_unused, the definition used in the
kernel for __attribute__((unused)). In this way there is only one
definition in perf sources (instead of 2 definitions that point to the
same thing: __used and __unused) and it works on both Linux and Android.
This patch simply replaces all instances of __used and __unused with
__maybe_unused.
Signed-off-by: NIrina Tirdea <irina.tirdea@intel.com>
Acked-by: NPekka Enberg <penberg@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1347315303-29906-7-git-send-email-irina.tirdea@intel.com
[ committer note: fixed up conflict with a116e05d in builtin-sched.c ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      1d037ca1
  53. 31 5月, 2012 1 次提交