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    Subject[PATCH -tip v4 0/7] perf: Introduce branch sub commands

    This patch series provides the commands 'perf branch record' and
    'perf branch trace' version 4. These commands record and analyze
    a BTS (Branch Trace Store) log. And, they provide the interface
    to use BTS log for application developers.

    BTS is a facility of Intel x86 processors, which records the address of
    'branch to/from' on every branch/jump instruction and interrupt.
    This facility is very useful for developers to test their software,
    for example, coverage test, execution path analysis, dynamic step count ...etc.
    These test tools have a big advantage, which user doesn't have to modify target
    executable binaries, because the BTS is a hardware feauture.

    But, there are few applications using BTS. Reasons I guess are ...
    - Few people know what BTS is.
    - Few people know how to use BTS on Linux box.
    - It's hard to analyze the BTS log because it includes just a series of

    So, I want to provide a user-friendly interface to BTS for application

    About new sub commands
    'perf branch record' provides an easy way to record BTS log.
    Usage is 'perf branch record <command>'. This command is just an alias to
    'perf record -e branches:u -c 1 -d <command>'. But, new one is more simple
    and more intuitive.

    'perf branch trace' can parse and analyze recorded BTS log and print various
    information of execution path. This command can show address, pid, command name,
    function+offset, file path of elf.
    You can choose the printed information with option.

    Example: 'perf branch trace'

    _start+0x3 => _dl_start+0x0
    _dl_start+0x71 => _dl_start+0x93
    _dl_start+0x97 => _dl_start+0x78
    _dl_start+0x97 => _dl_start+0x78
    _dl_start+0xa3 => _dl_start+0x3c0
    _dl_start+0x3c8 => _dl_start+0x3e8

    This is the default behavior of 'perf branch trace'. It prints function+offset.

    Example2: 'perf branch -cas trace'
    command address function+offset
    ls 0x0000003e9b000b23 _start+0x3 => 0x0000003e9b004540 _dl_start+0x0
    ls 0x0000003e9b0045b1 _dl_start+0x71 => 0x0000003e9b0045d3 _dl_start+0x93
    ls 0x0000003e9b0045d7 _dl_start+0x97 => 0x0000003e9b0045b8 _dl_start+0x78
    ls 0x0000003e9b0045d7 _dl_start+0x97 => 0x0000003e9b0045b8 _dl_start+0x78
    ls 0x0000003e9b0045e3 _dl_start+0xa3 => 0x0000003e9b004900 _dl_start+0x3c0
    ls 0x0000003e9b004908 _dl_start+0x3c8 => 0x0000003e9b004928 _dl_start+0x3e8

    In the future, I'd like to make this more informative. For example
    - Show source file path
    - Show line number
    - Show inlined function name
    - Draw call graph
    - Browse source code and coloring
    - Make BTS record fast
    and more!

    Changes in V4:
    - Add kenel filter
    - Print PID and command only once in a line
    - Add output TSV mode

    Changes in V3:
    - Update to the latest -tip tree
    - Rename to 'perf branch'
    - Process only BTS records
    - Fix bug of getting elf_filepath
    - Fix return value of __cmd_trace

    Changes in V2:
    - Update to the latest -tip tree
    - Add bts explanation to the subcommand list
    - Remove the patch already merged (add OPT_CALLBACK_DEFAULT_NOOPT)
    - Add comments
    - Add new function to the todo list



    Akihiro Nagai (7):
    perf branch trace: add kernel filter
    perf branch trace: add print all option
    perf branch trace: print function+offset
    perf branch trace: print file path of the executed elf
    perf branch trace: print pid and command
    perf branch: Introduce new sub command 'perf branch trace'
    perf: new subcommand perf branch record

    tools/perf/Documentation/perf-branch.txt | 62 +++++
    tools/perf/Makefile | 1
    tools/perf/builtin-branch.c | 361 ++++++++++++++++++++++++++++++
    tools/perf/builtin.h | 1
    tools/perf/command-list.txt | 1
    tools/perf/perf.c | 1
    6 files changed, 427 insertions(+), 0 deletions(-)
    create mode 100644 tools/perf/Documentation/perf-branch.txt
    create mode 100644 tools/perf/builtin-branch.c

    Akihiro Nagai (

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