mainlining shenanigans
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Milian Wolff 1fb7d06a50 perf report: Use srcline from callchain for hist entries
This also removes the symbol name from the srcline column, more on this
below.

This ensures we use the correct srcline, which could originate from a
potentially inlined function. The hist entries used to query for the
srcline based purely on the IP, which leads to wrong results for inlined
entries.

Before:

~~~~~
  perf report --inline -s srcline -g none --stdio
  ...
  # Children      Self  Source:Line
  # ........  ........  ..................................................................................................................................
  #
      94.23%     0.00%  __libc_start_main+18446603487898210537
      94.23%     0.00%  _start+41
      44.58%     0.00%  main+100
      44.58%     0.00%  std::_Norm_helper<true>::_S_do_it<double>+100
      44.58%     0.00%  std::__complex_abs+100
      44.58%     0.00%  std::abs<double>+100
      44.58%     0.00%  std::norm<double>+100
      36.01%     0.00%  hypot+18446603487892193300
      25.81%     0.00%  main+41
      25.81%     0.00%  std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator()+41
      25.81%     0.00%  std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >+41
      25.75%    25.75%  random.h:143
      18.39%     0.00%  main+57
      18.39%     0.00%  std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator()+57
      18.39%     0.00%  std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >+57
      13.80%    13.80%  random.tcc:3330
       5.64%     0.00%  ??:0
       4.13%     4.13%  __hypot_finite+163
       4.13%     0.00%  __hypot_finite+18446603487892193443
...
~~~~~

After:

~~~~~
  perf report --inline -s srcline -g none --stdio
  ...
  # Children      Self  Source:Line
  # ........  ........  ...........................................
  #
      94.30%     1.19%  main.cpp:39
      94.23%     0.00%  __libc_start_main+18446603487898210537
      94.23%     0.00%  _start+41
      48.44%     1.70%  random.h:1823
      48.44%     0.00%  random.h:1814
      46.74%     2.53%  random.h:185
      44.68%     0.10%  complex:589
      44.68%     0.00%  complex:597
      44.68%     0.00%  complex:654
      44.68%     0.00%  complex:664
      40.61%    13.80%  random.tcc:3330
      36.01%     0.00%  hypot+18446603487892193300
      26.81%     0.00%  random.h:151
      26.81%     0.00%  random.h:332
      25.75%    25.75%  random.h:143
       5.64%     0.00%  ??:0
       4.13%     4.13%  __hypot_finite+163
       4.13%     0.00%  __hypot_finite+18446603487892193443
...
~~~~~

Note that this change removes the symbol from the source:line hist
column. If this information is desired, users should explicitly query
for it if needed. I.e. run this command instead:

~~~~~
  perf report --inline -s sym,srcline -g none --stdio
  ...
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'cycles:uppp'
  # Event count (approx.): 1381229476
  #
  # Children      Self  Symbol                                                                                                                               Source:Line
  # ........  ........  ...................................................................................................................................  ...........................................
  #
      94.30%     1.19%  [.] main                                                                                                                             main.cpp:39
      94.23%     0.00%  [.] __libc_start_main                                                                                                                __libc_start_main+18446603487898210537
      94.23%     0.00%  [.] _start                                                                                                                           _start+41
      48.44%     0.00%  [.] std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > (inlined)  random.h:1814
      48.44%     0.00%  [.] std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > (inlined)  random.h:1823
      46.74%     0.00%  [.] std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator() (inlined)  random.h:185
      44.68%     0.00%  [.] std::_Norm_helper<true>::_S_do_it<double> (inlined)                                                                              complex:654
      44.68%     0.00%  [.] std::__complex_abs (inlined)                                                                                                     complex:589
      44.68%     0.00%  [.] std::abs<double> (inlined)                                                                                                       complex:597
      44.68%     0.00%  [.] std::norm<double> (inlined)                                                                                                      complex:664
      39.80%    13.59%  [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >               random.tcc:3330
      36.01%     0.00%  [.] hypot                                                                                                                            hypot+18446603487892193300
      26.81%     0.00%  [.] std::__detail::__mod<unsigned long, 2147483647ul, 16807ul, 0ul> (inlined)                                                        random.h:151
      26.81%     0.00%  [.] std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>::operator() (inlined)                                 random.h:332
      25.75%     0.00%  [.] std::__detail::_Mod<unsigned long, 2147483647ul, 16807ul, 0ul, true, true>::__calc (inlined)                                     random.h:143
      25.19%    25.19%  [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >               random.h:143
       4.13%     4.13%  [.] __hypot_finite                                                                                                                   __hypot_finite+163
       4.13%     0.00%  [.] __hypot_finite                                                                                                                   __hypot_finite+18446603487892193443
...
~~~~~

Compared to the old behavior, this reduces duplication in the output.
Before we used to print the symbol name in the srcline column even
when the sym column was explicitly requested. I.e. the output was:

~~~~~
  perf report --inline -s sym,srcline -g none --stdio
  ...
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'cycles:uppp'
  # Event count (approx.): 1381229476
  #
  # Children      Self  Symbol                                                                                                                               Source:Line
  # ........  ........  ...................................................................................................................................  ..................................................................................................................................
  #
      94.23%     0.00%  [.] __libc_start_main                                                                                                                __libc_start_main+18446603487898210537
      94.23%     0.00%  [.] _start                                                                                                                           _start+41
      44.58%     0.00%  [.] main                                                                                                                             main+100
      44.58%     0.00%  [.] std::_Norm_helper<true>::_S_do_it<double> (inlined)                                                                              std::_Norm_helper<true>::_S_do_it<double>+100
      44.58%     0.00%  [.] std::__complex_abs (inlined)                                                                                                     std::__complex_abs+100
      44.58%     0.00%  [.] std::abs<double> (inlined)                                                                                                       std::abs<double>+100
      44.58%     0.00%  [.] std::norm<double> (inlined)                                                                                                      std::norm<double>+100
      36.01%     0.00%  [.] hypot                                                                                                                            hypot+18446603487892193300
      25.81%     0.00%  [.] main                                                                                                                             main+41
      25.81%     0.00%  [.] std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator() (inlined)  std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator()+41
      25.81%     0.00%  [.] std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > (inlined)  std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >+41
      25.69%    25.69%  [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >               random.h:143
      18.39%     0.00%  [.] main                                                                                                                             main+57
      18.39%     0.00%  [.] std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator() (inlined)  std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator()+57
      18.39%     0.00%  [.] std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > (inlined)  std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >+57
      13.80%    13.80%  [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >               random.tcc:3330
       4.13%     4.13%  [.] __hypot_finite                                                                                                                   __hypot_finite+163
       4.13%     0.00%  [.] __hypot_finite                                                                                                                   __hypot_finite+18446603487892193443
...
~~~~~

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171019113836.5548-5-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-10-25 10:50:46 -03:00
arch Merge branch 'perf/urgent' into perf/core, to pick up fixes 2017-10-20 11:02:05 +02:00
block bio_copy_user_iov(): don't ignore ->iov_offset 2017-10-10 23:55:14 -04:00
certs modsign: add markers to endif-statements in certs/Makefile 2017-07-14 11:01:37 +10:00
crypto crypto: shash - Fix zero-length shash ahash digest crash 2017-10-11 00:34:07 +08:00
Documentation kprobes/docs: Remove jprobes related documents 2017-10-20 11:02:55 +02:00
drivers lkdtm, kprobes: Convert from jprobes to kprobes 2017-10-23 13:52:45 +02:00
firmware firmware: Restore support for built-in firmware 2017-09-16 10:58:48 -07:00
fs membarrier: Provide register expedited private command 2017-10-19 22:13:40 -04:00
include kprobes: Disable the jprobes APIs 2017-10-20 11:02:29 +02:00
init Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ipc fix a typo in put_compat_shm_info() 2017-09-25 20:41:46 -04:00
kernel kprobes: Disable the jprobes test code 2017-10-20 11:02:54 +02:00
lib Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-14 15:14:20 -04:00
mm mm, swap: use page-cluster as max window of VMA based swap readahead 2017-10-13 16:18:33 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-09 16:25:00 -07:00
samples kprobes: Remove the jprobes sample code 2017-10-20 11:02:55 +02:00
scripts scripts/kallsyms.c: ignore symbol type 'n' 2017-10-13 16:18:32 -07:00
security lsm: fix smack_inode_removexattr and xattr_getsecurity memleak 2017-10-04 18:03:15 +11:00
sound ALSA: hda - Fix incorrect TLV callback check introduced during set_fs() removal 2017-10-18 12:27:00 +02:00
tools perf report: Use srcline from callchain for hist entries 2017-10-25 10:50:46 -03:00
usr ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk. 2017-07-06 16:24:30 -07:00
virt Revert "KVM: Don't accept obviously wrong gsi values via KVM_IRQFD" 2017-09-19 08:37:17 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap Update James Hogan's email address 2017-10-04 17:11:53 -07:00
COPYING
CREDITS selinux/stable-4.14 PR 20170831 2017-09-12 13:21:00 -07:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS perf/urgent fixes: 2017-10-20 09:14:06 +02:00
Makefile Linux 4.14-rc5 2017-10-15 21:01:12 -04:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.