Re: [GIT PULL 0/7] perf/core improvements and fixes

[Ingo Molnar <mingo@kernel.org>]

* Arnaldo Carvalho de Melo <acme@kernel.org> wrote:

> Hi Ingo,
> 
> 	Please consider pulling,
> 
> - Arnaldo
> 
> 
> The following changes since commit b7883a1c4f75edb62fc49da6000c59fb881e3c7b:
> 
>   perf/x86: Handle multiple umask bits for BDW CYCLE_ACTIVITY.* (2015-11-23 09:58:27 +0100)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-core-for-mingo
> 
> for you to fetch changes up to 646a6e846c4dc3812c614fd061603b6db5b8d380:
> 
>   perf callchain: Add missing parent_val initialization (2015-11-23 18:31:25 -0300)
> 
> ----------------------------------------------------------------
> perf/core improvements and fixes:
> 
> User visible:
> 
> - Allow callchain order (caller, callee) to the libdw and libunwind based DWARF
>   unwinders (Jiri Olsa)
> 
> - Add missing parent_val initialization in the callchain code, fixing a
>   SEGFAULT when using callchains with 'perf top' (Jiri Olsa)
> 
> - Add initial 'perf config' command, for now just with a --list command to
>   show the contents of the configuration file in use and a basic man page
>   describing its format, commands for doing edits and detailed documentation
>   are being reviewed and proof-read. (Taeung Song)
> 
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> 
> ----------------------------------------------------------------
> Jiri Olsa (5):
>       perf callchain: Move initial entry call into get_entries function
>       perf callchain: Add order support for libunwind DWARF unwinder
>       perf test: Add callchain order setup for DWARF unwinder test
>       perf callchain: Add order support for libdw DWARF unwinder
>       perf callchain: Add missing parent_val initialization
> 
> Taeung Song (2):
>       perf tools: Add 'perf config' command
>       perf config: Add initial man page
> 
>  tools/perf/Build                         |   1 +
>  tools/perf/Documentation/perf-config.txt | 103 +++++++++++++++++++++++++++++++
>  tools/perf/builtin-config.c              |  66 ++++++++++++++++++++
>  tools/perf/builtin.h                     |   1 +
>  tools/perf/command-list.txt              |   1 +
>  tools/perf/perf.c                        |   1 +
>  tools/perf/tests/dwarf-unwind.c          |  22 ++++++-
>  tools/perf/util/callchain.h              |   1 +
>  tools/perf/util/unwind-libdw.c           |  53 +++++++++++-----
>  tools/perf/util/unwind-libdw.h           |   2 +
>  tools/perf/util/unwind-libunwind.c       |  60 +++++++++++-------
>  11 files changed, 272 insertions(+), 39 deletions(-)
>  create mode 100644 tools/perf/Documentation/perf-config.txt
>  create mode 100644 tools/perf/builtin-config.c

Hm, I noticed something weird - I think it started with this pull request - the 
feature detection build messages come mixed with the regular build:

triton:~/tip/tools/perf> make
  BUILD:   Doing 'make -j12' parallel build

Auto-detecting system features:
...                         dwarf: [ on  ]
...                         glibc: [ on  ]
...                          gtk2: [ on  ]
...                      libaudit: [ on  ]
...                        libbfd: [ on  ]
...                        libelf: [ on  ]
...                       libnuma: [ on  ]
...        numa_num_possible_cpus: [ on  ]
...                       libperl: [ on  ]
...                     libpython: [ on  ]
...                      libslang: [ on  ]
...                     libunwind: [ on  ]
...            libdw-dwarf-unwind: [ on  ]
...                          zlib: [ on  ]
...                          lzma: [ on  ]
...                     get_cpuid: [ on  ]
...                           bpf: [ on  ]

  GEN      common-cmds.h
  CC       perf-read-vdso32
  CC       perf-read-vdsox32
  CC       ui/gtk/browser.o
  CC       ui/gtk/hists.o
  CC       ui/gtk/setup.o
  CC       ui/gtk/util.o
  CC       ui/gtk/helpline.o
  CC       ui/gtk/progress.o
  CC       ui/gtk/annotate.o
  CC       util/abspath.o
  CC       fd/array.o

Auto-detecting system features:
  CC       event-parse.o
...                        libelf: [ on  ]
  PERF_VERSION = 4.4.rc2.g9327ca
...                           bpf: [ on  ]

  CC       util/alias.o
  CC       libbpf.o


while normally we'd first do feature detection, then only do the build (knowing 
which features to build).

Occasionally it also triggers a build failure:

  CC       plugin_kvm.o
  CC       arch/common.o
  CC       util/db-export.o
  LD       plugin_kmem-in.o
fixdep: error opening depfile: ./.plugin_kmem.o.d: No such file or directory
/home/mingo/tip/tools/build/Makefile.build:77: recipe for target 'plugin_kmem.o' 
failed
make[3]: *** [plugin_kmem.o] Error 2
Makefile:189: recipe for target 'plugin_kmem-in.o' failed
make[2]: *** [plugin_kmem-in.o] Error 2
Makefile.perf:424: recipe for target 'install-traceevent-plugins' failed
make[1]: *** [install-traceevent-plugins] Error 2
make[1]: *** Waiting for unfinished jobs....

that too seems to be a result of unwanted, over-eager parallelism.

Thanks,

	Ingo